Eos Energy Enterprises (EOSE) 10-Q9 May 232023 Q1 Quarterly reportFinancial data

Company Profile

Cover

Cover - shares	3 Months Ended
Cover - shares	Mar. 31, 2023	May 04, 2023
Document Information [Line Items]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Mar. 31, 2023
Document Transition Report	false
Entity File Number	001-39291
Entity Registrant Name	EOS ENERGY ENTERPRISES, INC.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	84-4290188
Entity Address, Address Line One	3920 Park Avenue
Entity Address, City or Town	Edison
Entity Address, State or Province	NJ
Entity Address, Postal Zip Code	08820
City Area Code	732
Local Phone Number	225-8400
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding (in shares)		115,848,976
Entity Central Index Key	0001805077
Amendment Flag	false
Current Fiscal Year End Date	--12-31
Document Fiscal Period Focus	Q1
Document Fiscal Year Focus	2023
Common stock
Document Information [Line Items]
Title of 12(b) Security	Common stock, par value $0.0001 per share
Trading Symbol	EOSE
Security Exchange Name	NASDAQ
Public and private placement warrants
Document Information [Line Items]
Title of 12(b) Security	Warrants, each exercisable for one share of common stock
Trading Symbol	EOSEW
Security Exchange Name	NASDAQ

UNAUDITED CONDENSED CONSOLIDATE

UNAUDITED CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Current assets:
Cash and cash equivalents	$ 16,127	$ 17,076
Restricted cash	2,725	2,725
Accounts receivable, net	3,660	1,666
Inventory, net	14,075	23,260
Vendor deposits	5,668	4,789
Notes receivable, net	45	36
Contract assets, current	3,844	1,859
Prepaid expenses	1,884	2,289
Other current assets	1,999	1,447
Total current assets	50,027	55,147
Property, plant and equipment, net	24,617	27,169
Intangible assets, net	350	240
Goodwill	4,331	4,331
Notes receivable, long-term, net	817	827
Operating lease right-of-use asset, net	4,083	4,316
Long-term restricted cash	11,450	11,422
Other assets	4,050	3,336
Total assets	99,725	106,788
Current liabilities:
Accounts payable	32,531	34,669
Accrued expenses	20,351	15,359
Operating lease liability, current	1,149	1,106
Long-term debt, current	2,981	2,872
Convertible notes payable, current - related party	8,240	2,688
Contract liabilities, current	400	3,850
Other current liabilities	34	32
Total current liabilities	65,686	60,576
Long-term liabilities:
Operating lease liability	3,825	4,130
Long-term debt	87,450	87,321
Convertible notes payable - related party	111,114	82,950
Interest payable - related party	2,417	0
Contract liabilities, long-term	956	956
Warrants liability - related party	234	78
Other liabilities	3,640	3,488
Total long-term liabilities	209,636	178,923
Total liabilities	275,322	239,499
COMMITMENTS AND CONTINGENCIES (NOTE 15)
SHAREHOLDERS' DEFICIT
Common Stock, $0.0001 par value, 300,000,000 and 300,000,000 shares authorized, 95,222,670 and 82,653,781 shares outstanding on March 31, 2023 and December 31, 2022, respectively	10	9
Preferred stock, $0.0001 par value, 1,000,000 shares authorized, no shares outstanding on March 31, 2023 and December 31, 2022	0	0
Additional paid in capital	542,326	513,614
Accumulated deficit	(717,940)	(646,340)
Accumulated other comprehensive income	7	6
Total shareholders' deficit	(175,597)	(132,711)
Total liabilities and shareholders' deficit	$ 99,725	$ 106,788

UNAUDITED CONDENSED CONSOLIDA_2

UNAUDITED CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) - $ / shares	Mar. 31, 2023	Dec. 31, 2022
Statement of Financial Position [Abstract]
Common stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Common stock, shares authorized (in shares)	300,000,000	300,000,000
Common stock, shares issued (in shares)	95,222,670	82,653,781
Common stock, shares outstanding (in shares)	95,222,670	82,653,781
Preferred stock issued per unit (in dollars per share)	$ 0.0001	$ 0.0001
Preferred stock, shares authorized (in shares)	1,000,000	1,000,000
Preferred stock, shares issued (in shares)	0	0
Preferred stock, shares outstanding (in shares)	0	0

UNAUDITED CONDENSED CONSOLIDA_3

UNAUDITED CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Revenue
Total revenue	$ 8,835	$ 3,298
Costs and expenses
Cost of goods sold	26,940	35,577
Research and development expenses	5,445	4,963
Selling, general and administrative expenses	13,955	14,279
Loss from write-down of property, plant and equipment	760	8
Grant expense, net	0	173
Total costs and expenses	47,100	55,000
Operating loss	(38,265)	(51,702)
Other (expense) income
(Loss) gain on change in fair value of derivatives - related parties	(13,090)	8,262
Loss on debt extinguishment	(1,634)	0
Other (expense) income	(17)	119
Loss before income taxes	(71,590)	(45,833)
Income tax expense (benefit)	10	(42)
Net loss	(71,600)	(45,791)
Other comprehensive income
Foreign currency translation adjustment, net of tax	1	0
Comprehensive loss	$ (71,599)	$ (45,791)
Basic and diluted loss per share attributable to common shareholders
Basic (in dollars per share)	$ (0.82)	$ (0.85)
Diluted (in dollars per share)	$ (0.82)	$ (0.85)
Weighted average shares of common stock
Basic (in shares)	86,797,669	53,961,553
Diluted (in shares)	86,797,669	53,961,553
Nonrelated Party
Other (expense) income
Interest expense, net	$ (4,829)	$ (338)
Related Party
Other (expense) income
Interest expense, net	$ (13,755)	$ (2,174)

UNAUDITED CONDENSED CONSOLIDA_4

UNAUDITED CONDENSED CONSOLIDATED STATEMENTS OF SHAREHOLDERS' DEFICIT - USD ($) $ in Thousands	Total	Common stock	Additional Paid-in Capital	Accumulated Other Comprehensive Income	Accumulated Deficit
Beginning balances (in shares) at Dec. 31, 2021		53,786,632
Beginning balances at Dec. 31, 2021	$ 32,447	$ 5	$ 448,969	$ 0	$ (416,527)
Increase (decrease) in stockholders' equity [Roll Forward]
Stock-based compensation	3,943		3,943
Exercise of warrants (in shares)		600
Exercise of warrants	7		7
Release of restricted stock units (in shares)		305,651
Cancellation of shares used to settle payroll tax withholding (in shares)		(112,275)
Cancellation of shares used to settle payroll tax withholding	(826)		(826)
Foreign currency translation adjustment, net of tax	0
Net loss	(45,791)				(45,791)
Ending balances (in shares) at Mar. 31, 2022		53,980,608
Ending balances at Mar. 31, 2022	$ (10,220)	$ 5	452,093	0	(462,318)
Beginning balances (in shares) at Dec. 31, 2022	82,653,781	82,653,781
Beginning balances at Dec. 31, 2022	$ (132,711)	$ 9	513,614	6	(646,340)
Increase (decrease) in stockholders' equity [Roll Forward]
Stock-based compensation	3,363		3,363
Exercise of warrants (in shares)		0
Release of restricted stock units (in shares)		915,206
Cancellation of shares used to settle payroll tax withholding (in shares)		(246,717)
Cancellation of shares used to settle payroll tax withholding	(345)		(345)
Issuance of common stock under Yorkville Promissory Notes (in shares)		11,216,492
Issuance of common stock under Yorkville Promissory Notes	24,423	$ 1	24,422
Issuance of common stock under SEPA (in shares)		683,908
Issuance of common stock under SEPA	1,272	$ 0	1,272
Foreign currency translation adjustment, net of tax	1			1
Net loss	$ (71,600)				(71,600)
Ending balances (in shares) at Mar. 31, 2023	95,222,670	95,222,670
Ending balances at Mar. 31, 2023	$ (175,597)	$ 10	$ 542,326	$ 7	$ (717,940)

UNAUDITED CONDENSED CONSOLIDA_5

UNAUDITED CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Cash flows from operating activities
Net loss	$ (71,600)	$ (45,791)
Adjustment to reconcile net loss to net cash used in operating activities
Stock-based compensation	3,363	3,943
Depreciation and amortization	2,686	995
Loss on debt extinguishment	1,634	0
Loss from write-down of property, plant and equipment	760	8
Amortization of right-of-use assets	233	192
Non-cash interest expense	915	0
Non-cash interest expense - related parties	11,338	630
Loss (gain) on change in fair value of derivatives - related parties	13,090	(8,262)
Changes in operating assets and liabilities:
Prepaid expenses	406	102
Inventory	9,185	2,684
Accounts receivable	(1,984)	(768)
Vendor deposits	(917)	(2,258)
Contract assets	(1,914)	431
Accounts payable	(208)	(1,172)
Accrued expenses	4,991	5,126
Accounts payable and accrued expenses - related parties	0	(1,200)
Interest payable - related party	2,417	1,544
Operating lease liabilities	(262)	(179)
Contract liabilities	(3,450)	2,074
Note payable	0	167
Other	(1,161)	(998)
Net cash used in operating activities	(30,478)	(42,732)
Cash flows from investing activities
Purchases of property, plant and equipment	(2,897)	(5,132)
Net cash used in investing activities	(2,897)	(5,132)
Cash flows from financing activities
Principal payments on finance lease obligations	(7)	(4)
Proceeds from exercise of public warrants	0	7
Proceeds from issuance of convertible notes - related parties	33,350	0
Payment of debt issuance costs - related parties	(1,116)	0
Repayment of equipment financing facility	(677)	(389)
Repurchase of shares from employees for income tax withholding purposes	(345)	(826)
Net cash provided by (used in) financing activities	32,455	(1,212)
Effect of exchange rate changes on cash, cash equivalents and restricted cash	(1)	0
Net decrease in cash, cash equivalents and restricted cash	(921)	(49,076)
Cash, cash equivalents and restricted cash, beginning of the period	31,223	105,692
Cash, cash equivalents and restricted cash, end of the period	30,302	56,616
Non-cash investing and financing activities
Accrued and unpaid capital expenditures	603	878
Issuance of common stock upon settlement of Yorkville convertible notes	24,422	0
Right-of-use operating lease assets in exchange for lease liabilities	0	2,112
Accrued and unpaid capitalized internal-use software	130	0
Supplemental disclosures
Cash paid for interest	3,690	224
Private Placement
Cash flows from financing activities
Issuance of common stock under SEPA	$ 1,250	$ 0

Overview

Overview	3 Months Ended
Overview	Mar. 31, 2023
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Overview	Overview Nature of Operations Eos Energy Enterprises, Inc. (the “Company,” “we,” “us,” “our,” and “Eos”) designs, develops, manufactures, and markets innovative energy storage solutions for utility-scale, microgrid, and commercial & industrial (“C&I”) applications. Eos developed a broad range of intellectual property with multiple patents covering unique battery chemistry, mechanical product design, energy block configuration and a software operating system (Battery Management System). The Company has only one operating and reportable segment. Liquidity and Going Concern As a growth company in the early commercialization stage of its lifecycle, Eos is subject to inherent risks and uncertainties associated with the development of an enterprise. In this regard, substantially all of the Company’s efforts to date have been devoted to the development and manufacturing of battery energy storage systems and complimentary products and services, recruitment of management and technical staff, deployment of capital to expand the Company’s operations to meet customer demand and raising capital to fund the Company’s development. As a result of these efforts, the Company has incurred significant losses and negative cash flows from operations since its inception and expects to continue to incur such losses and negative cash flows for the foreseeable future until such time that the Company can reach a scale of profitability to sustain its operations. In order to execute its development strategy, the Company has historically relied on outside capital through the issuance of equity, debt, and borrowings under financing arrangements (collectively “outside capital”) to fund its cost structure and expects to continue to rely on outside capital for the foreseeable future. While the Company believes it will eventually reach a scale of profitability to sustain its operations, there can be no assurance the Company will be able to achieve such profitability or do so in a manner that does not require its continued reliance on outside capital. Moreover, while the Company has historically been successful in raising outside capital, there can be no assurance the Company will be able to continue to obtain outside capital in the future or do so on terms that are acceptable to the Company. As of the date the accompanying unaudited condensed consolidated financial statements were issued (the “issuance date”), management evaluated the significance of the following negative financial conditions in accordance with Accounting Standard Codification 205-40, Going Concern: • Since its inception, the Company has incurred significant losses and negative cash from operations in order to fund its development. During the three months ended March 31, 2023, the Company incurred a net loss of $71,600, incurred negative cash flows from operations of $30,478, and had an accumulated deficit of $717,940 as of March 31, 2023. • As of March 31, 2023, the Company had $16,127 of unrestricted cash and cash equivalents available to fund the Company’s operations, no additional borrowings available to fund its operations under pre-existing financing arrangements (see Note 12, Borrowings ) and negative working capital of $15,659, inclusive of $11,221 of outstanding debt that is currently scheduled to mature within the next twelve months beyond the issuance date. • While the Company has available capacity under certain pre-existing arrangements to issue shares of the Company’s common stock, including under the Standby Equity Purchase Agreement with YA II PN, Ltd. (“SEPA”), subject to the exchange cap, and at-the-market (“ATM”) offering program, (see Note 18, Shareholders’ Deficit ) to aid in funding the Company’s operations, the Company’s ability to secure such funding is dependent upon certain conditions, such as investors’ willingness to purchase the Company’s common stock and at a price that is acceptable to the Company. Accordingly, as of the issuance date there is no assurance the Company will be able to secure funding under these pre-existing arrangements or on terms that are acceptable to the Company. • Similarly, while the Company has historically been successful in raising additional outside capital to fund the Company’s operations, as of the issuance date no assurance can be provided the Company will be successful in obtaining additional outside capital or on terms that are acceptable to the Company. In this regard, the Company has substantially completed the due diligence phase of negotiating additional outside capital under the U.S. Department of Energy’s (“DOE”) Loan Guarantee Solicitation for Applications for Renewable Energy Projects and Efficient Energy Projects (the “DOE Loan Program”). There can be no assurance that the Company will be able to secure such a loan or on terms that are acceptable to the Company. • The Company is required to remain in compliance with a quarterly minimum financial liquidity covenant under its Senior Secured Term Loan Credit Agreement (“Senior Secured Term Loan”). While the Company was in compliance with this covenant as of March 31, 2023, and expects to remain in compliance as of June 30, 2023, absent the Company’s ability to secure additional outside capital, the Company may be unable to remain in compliance with this covenant beginning on September 30, 2023 and thereafter. In the event the Company is unable to remain in compliance with the minimum financial liquidity covenant and the other nonfinancial covenants required by the Senior Secured Term Loan, and the Company is further unable to cure such noncompliance or secure a waiver, Atlas Credit Partners (ACP) Post Oak Credit I LLC may, at its discretion, exercise any and all of its existing rights and remedies, which may include, among other things, entering into a forbearance agreement with the Company, and/or asserting its rights in the Company’s assets securing the loan. Moreover, the Company’s other lenders may exercise similar rights and remedies under the cross-default provisions of their respective borrowing arrangements with the Company. • Absent an ability to secure additional outside capital in the near term, the Company will be unable to meet its obligations as they become due over the next twelve months beyond the issuance date. • In the event the Company’s ongoing efforts to raise additional outside capital prove unsuccessful, management will be required to seek other strategic alternatives, which may include, among others, a significant curtailment in the Company’s operations, a sale of certain of the Company’s assets, a sale of the entire Company to strategic or financial investors, and/or allowing the Company to become insolvent. These uncertainties raise substantial doubt about the Company’s ability to continue as a going concern. The accompanying unaudited condensed consolidated financial statements have been prepared on the basis that the Company will continue to operate as a going concern, which contemplates that the Company will be able to realize assets and settle liabilities and commitments in the normal course of business for the foreseeable future. Accordingly, the accompanying unaudited condensed consolidated financial statements do not include any adjustments that may result from the outcome of these uncertainties.

Summary of Significant Accounti

Summary of Significant Accounting Policies	3 Months Ended
Summary of Significant Accounting Policies	Mar. 31, 2023
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	Summary of Significant Accounting Policies Basis of Presentation The accompanying unaudited condensed consolidated financial statements include the accounts of the Company and its 100% owned, direct and indirect subsidiaries and have been prepared in accordance with U.S. generally accepted accounting principles (“GAAP”). All intercompany transactions and balances have been eliminated in the preparation of the unaudited condensed consolidated financial statements. These statements reflect all adjustments, consisting of normal recurring adjustments, which, in the opinion of management, are necessary for fair presentation of the information contained therein. Certain information and footnote disclosures normally included in financial statements prepared in accordance with GAAP have been condensed or omitted pursuant to the rules and regulations of the U.S. Securities and Exchange Commission (“SEC”). The interim financial statements should be read in conjunction with the audited consolidated financial statements, including the notes thereto, included in our 2022 Annual Report on Form 10-K. These interim results are not necessarily indicative of results for the full year. Use of Estimates The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amount of revenues and expenses during the reporting period. Actual results could differ from those estimates. Reclassification of Prior Year Presentation Certain prior year amounts have been reclassified for consistency with the current year presentation. These reclassifications had no effect on the reported results of operations. Recent Accounting Pronouncements There were no new accounting standards or updates during the three months ended March 31, 2023 that would have a material impact on the Company’s unaudited condensed consolidated financial statements.

Revenue Recognition

Revenue Recognition	3 Months Ended
Revenue Recognition	Mar. 31, 2023
Revenue from Contract with Customer [Abstract]
Revenue Recognition	Revenue Recognition The Company primarily earns revenue from sales of its energy storage systems and services including installation, commissioning, and extended warranty services. Product revenues, which are generally recognized at a point in time, and service revenues, which are generally recognized over time, are as follows: For the Three Months Ended March 31, 2023 2022 Product revenue $ 8,675 $ 3,293 Service revenue 160 5 Total revenues $ 8,835 $ 3,298 For the three months ended March 31, 2023, the Company had one customer who accounted for approximately 97.0% of the total revenue. For the three months ended March 31, 2022, the Company had three customers who accounted for 43.6%, 31.5% and 15.1% of the total revenue, respectively. Contract assets and Contract liabilities The following table provides information about contract assets and contract liabilities from contracts with customers. Contract assets, current and contract liabilities, current and long-term are included separately on the unaudited condensed consolidated balance sheets and contract assets, long-term are included under other assets, net. March 31, December 31, Contract assets $ 3,914 $ 2,000 Contract liabilities $ 1,356 $ 4,806 The Company recognizes contract assets for certain contracts in which revenue recognition performance obligations have been satisfied but invoicing to the customer has not yet occurred. Contract liabilities primarily relate to consideration received from customers in advance of the Company’s satisfying performance obligations under contractual arrangements. Contract balances are reported in a net contract asset or liability position on a contract-by-contract basis at the end of each reporting period. Contract assets increased by $1,914 during the three months ended March 31, 2023 due to recognition of revenues for which invoicing has not yet occurred. Contract liabilities decreased by $3,450 during the three months ended March 31, 2023, due to the recognition of $3,450 of revenue during the three months ended March 31, 2023 that was included in the contract liability balance at the beginning of the period. Contract liabilities of $400 as of March 31, 2023 are expected to be recognized within the next twelve months and long-term contract liabilities of $956 are expected to be recognized as revenue over approximately the next one to two years. Contract assets of $3,844 as of March 31, 2023 are expected to be recognized within the next twelve months. Long-term contract assets of $70 are expected to be recognized as accounts receivable over approximately the next two years.

Cash, Cash Equivalents and Rest

Cash, Cash Equivalents and Restricted Cash	3 Months Ended
Cash, Cash Equivalents and Restricted Cash	Mar. 31, 2023
Cash and Cash Equivalents [Abstract]
Cash, Cash Equivalents and Restricted Cash	Cash, Cash Equivalents and Restricted Cash Restricted cash - current consists of escrow deposits related to U.S. Custom Bonds insurance and escrow deposits related to our credit card program agreements. Additionally, long-term restricted cash relates to interest that is required to be held in escrow per the Senior Secured Term Loan agreement in an amount equal to the aggregate amount of the four immediately following interest payments owed (see Note 12, Borrowings for further discussion). The following table reconciles reported amounts from the unaudited condensed consolidated balance sheets to cash, cash equivalents and restricted cash reported within the unaudited condensed consolidated statements of cash flows: March 31, March 31, Cash and cash equivalents $ 16,127 $ 55,361 Restricted cash (1) 2,725 — Long-term restricted cash 11,450 1,255 Total cash, cash equivalents, and restricted cash $ 30,302 $ 56,616

Inventory

Inventory	3 Months Ended
Inventory	Mar. 31, 2023
Inventory Disclosure [Abstract]
Inventory	Inventory The following table provides information about inventory balances: March 31, December 31, Raw materials $ 13,896 $ 22,899 Work-in-process 64 361 Finished goods 115 — Total inventory, net $ 14,075 $ 23,260

Property, Plant and Equipment,

Property, Plant and Equipment, Net	3 Months Ended
Property, Plant and Equipment, Net	Mar. 31, 2023
Property, Plant and Equipment [Abstract]
Property, Plant and Equipment, Net	Property, Plant and Equipment, Net The following table provides information about property, plant and equipment, net balances: Estimated Useful lives March 31, December 31, Equipment 5 to 10 years $ 23,622 $ 23,653 Finance lease 5 years 379 379 Furniture 5 to 10 years 1,892 1,868 Leasehold improvements Lesser of useful life/ 6,629 6,303 Tooling 2 to 3 years 6,654 6,926 Total 39,176 39,129 Less: Accumulated depreciation (14,559) (11,960) Total property, plant and equipment, net $ 24,617 $ 27,169

Intangible Assets

Intangible Assets	3 Months Ended
Intangible Assets	Mar. 31, 2023
Goodwill and Intangible Assets Disclosure [Abstract]
Intangible Assets	Intangible Assets Intangible assets include patents valued at $400, which represents the cost to acquire the patents. These patents are determined to have useful lives and are amortized into the results of operations over ten years. The Company recorded amortization expense of $10 for each period for the three months ended March 31, 2023 and 2022 related to patents. During the three months ended March 31, 2023, the Company capitalized $130 of costs for internal-use software. The software has a useful life and is amortized into the results of operations over 3 years. The company recorded amortization expense of $9 for the three months ended March 31, 2023 related to software.

Notes Receivable, Net and Varia

Notes Receivable, Net and Variable Interest Entities (“VIEs”) Consideration	3 Months Ended
	Mar. 31, 2023
Receivables [Abstract]
Notes Receivable, Net and Variable Interest Entities (“VIEs”) Consideration	Notes Receivable, Net and Variable Interest Entities (“VIEs”) Consideration Notes receivable primarily consist of amounts due to the Company related to the financing offered to certain customers. The Company reports notes receivable at the principal balance outstanding less an allowance for losses. The estimate of credit losses is based on historical trends, customers’ financial condition and current economic trends. The Company charges interest at a fixed rate and calculates interest income by applying the effective rate to the outstanding principal balance. The Company had notes receivable, net of $862 and $863 outstanding as of March 31, 2023 and December 31, 2022, respectively. As of March 31, 2023 and December 31, 2022, the Company recorded an allowance for expected credit loss from the notes receivable of $2 and $2, respectively.

Accrued Expenses

Accrued Expenses	3 Months Ended
Accrued Expenses	Mar. 31, 2023
Payables and Accruals [Abstract]
Accrued Expenses	Accrued Expenses Accrued expenses were as follows: March 31, December 31, Accrued payroll $ 4,636 $ 2,706 Warranty reserve (1) 3,972 3,836 Accrued legal and professional expenses 2,087 840 Provision for contract losses 1,936 2,561 Insurance premium payable, current 2,730 2,607 Other 4,990 2,809 Total accrued expenses $ 20,351 $ 15,359 (1) Refer to the table below for the warranty reserve activity for the three months ended March 31, 2023. The following table summarizes warranty reserve activity: Three Months Ended 2023 2022 Warranty reserve - beginning of period $ 3,836 $ 2,112 Additions for current period deliveries 357 673 Changes in the warranty reserve estimate — 955 Warranty costs incurred (221) (500) Warranty reserve - end of period $ 3,972 $ 3,240

Government Grants

Government Grants	3 Months Ended
Government Grants	Mar. 31, 2023
Government Assistance [Abstract]
Government Grants	Government Grants California Energy Commission From time-to-time, the Company has entered into grant agreements with the California Energy Commission (“CEC”) for conducting studies to demonstrate the benefits of certain energy-saving technologies to utility companies and consumers in the State of California. Under such agreements, the Company is entitled to receive reimbursement of costs incurred by the Company covered by the grants. For the three months ended March 31, 2023 and 2022, grant expense, net was $0 and $173, respectively. As of March 31, 2023 and December 31, 2022, the Company had grant receivables related to the CEC in the amounts of $245 and $263, which were included in other current assets Inflation Reduction Act of 2022 (“IRA”) On August 16, 2022, President Biden signed the Inflation Reduction Act of 2022 into law. The IRA has significant economic incentives for both energy storage customers and manufacturers for projects placed in service after December 31, 2022. Starting in 2023, there are Production Tax Credits under Internal Revenue Code 45X (“PTC”), that can be claimed on battery components manufactured in the U.S. and sold to U.S. or foreign customers. These tax credits available to manufacturers include a credit for ten percent of the cost incurred to make electrode active materials in addition to credits of $35 per kWh of capacity of battery cells and $10 per kWh of capacity of battery modules. These credits are cumulative, meaning that companies will be able to claim each of the available tax credits based on the battery components produced and sold through 2029, after which the PTC will begin to gradually phase down through 2032. Since the PTC is a refundable credit (i.e., a credit with a direct-pay option available), the PTC is outside the scope of ASC 740. Therefore, the Company accounts for the PTC under a government grant model. GAAP does not address the accounting for government grants received by a business entity that are outside the scope of ASC 740. The Company’s accounting policy is to analogize to IAS 20, Accounting for Government Grants and Disclosure of Government Assistance, under IFRS Accounting Standards. Under IAS 20, once it is reasonably assured that the entity will comply with the conditions of the grant, the grant money should be recognized on a systematic basis over the periods in which the entity recognizes the related expenses or losses for which the grant money is intended to compensate. The Company recognizes grants once it is probable that both of the following conditions will be met: (1) the Company is eligible to receive the grant, and (2) the Company is able to comply with the relevant conditions of the grant. other assets

Related Party Transactions

Related Party Transactions	3 Months Ended
Related Party Transactions	Mar. 31, 2023
Related Party Transactions [Abstract]
Related Party Transactions	Related Party Transactions 2021 Convertible Notes Payable In July 2021, the Company issued $100,000 aggregate principal amount of convertible notes to Spring Creek Capital, LLC, a wholly-owned, indirect subsidiary of Koch Industries, Inc. (the “2021 Convertible Notes”). In connection with these 2021 Convertible Notes, the Company paid $3,000 to B. Riley Securities, Inc., a related party, who acted as a placement agent. Refer to Note 12, Borrowing s , for additional information. AFG Convertible Notes In January 2023, the Company issued and sold $13,750 of 26.5% Convertible Senior PIK Notes due 2026 (“AFG Convertible Notes”) to Great American Insurance Company, Ardsley Partners Renewable Energy, LP, CCI SPV III, LP, Denman Street LLC, John B. Berding Irrevocable Children’s Trust, John B. Berding, and AE Convert, LLC, a Delaware limited liability company managed by Russell Stidolph, a related party as Mr. Stidolph is a director of the Company (together, the “Purchasers”). In connection with the issuance and sale of the AFG Convertible Notes, the Company entered into an investment agreement (the “Investment Agreement”) with the Purchasers. Refer to Note 12, Borrowing s , for additional information. Warrants liability The Company issued private warrants to an affiliated company owned by B. Riley Financial, Inc. which were outstanding as of March 31, 2023 and December 31, 2022. Refer to Note 13, Warrants Liability - Related Party, for additional information. On April 28, 2022, the Company entered into the SEPA. Pursuant to the SEPA, the Company has the right, but not the obligation, to sell to Yorkville shares of its common stock at the Company’s request. See Note 12, Borrowings and Note 18, Shareholders' Deficit

Borrowings

Borrowings	3 Months Ended
Borrowings	Mar. 31, 2023
Debt Disclosure [Abstract]
Borrowings	Borrowings The Company’s debt obligations at carrying value consist of the following related and third-party borrowings: March 31, 2023 December 31, 2022 Borrowing Outstanding Carrying Value* Borrowing Outstanding Carrying Value* Yorkville Convertible Promissory Note - due August 2023 $ 6,000 $ 8,240 $ 2,000 $ 2,688 2021 Convertible Notes Payable - due June 2026 109,167 85,039 109,167 82,950 AFG Convertible Note - due June 2026 13,750 26,075 — — Senior Secured Term Loan - due March 2026 100,000 82,531 $ 100,000 $ 81,616 Equipment financing facility - due April 2025 7,900 7,900 8,577 8,577 Total borrowings 236,817 209,785 219,744 175,831 Current portion 11,221 11,221 5,560 5,560 Total borrowings, non-current $ 225,596 $ 198,564 $ 214,184 $ 170,271 * Carrying value includes unamortized deferred financing costs, unamortized discounts, and fair value of embedded derivative liabilities. Yorkville Convertible Promissory Notes - Related Party On December 29, 2022, the Company issued and sold a convertible promissory note (the “December 2022 Promissory Note”) with an aggregate principal amount of $2,000 in a private placement to Yorkville under a second supplemental agreement to the SEPA (the “Second Supplemental Agreement”). In January 2023, Yorkville delivered Investor Notices requiring the Company to issue and sell an aggregate of 1,953,612 shares of common stock to Yorkville to offset all outstanding amounts owed to Yorkville under the December 2022 Promissory Note. This resulted in a loss on debt extinguishment of $338 which is reflected in the unaudited condensed consolidated statements of operations and comprehensive loss. On February 1, 2023, the Company issued a convertible promissory note (the “February 2023 Promissory Note”) with an aggregate principal amount of $5,000 in a private placement to Yorkville under the Second Supplemental Agreement. The February 2023 Promissory Note has a maturity date of June 29, 2023, was issued with an original issue discount of 2%, debt issuance costs of $43, and bears an annual interest rate of 5% which shall increase to an annual rate of 15% upon an Event of Default (as defined in the SEPA) for so long as it remains uncured. The February 2023 Promissory Note is convertible into shares of the Company’s common stock at a conversion price equal to the lower of $1.4883 or 96.5% of the lowest daily volume weighted average price of the Company’s common stock during the seven consecutive trading days immediately preceding the conversion date (the “Conversion Price”). The number of shares issuable upon conversion of the February 2023 Promissory Note is subject to the Exchange Cap limitation under the SEPA, unless shareholder approval is obtained. Because shareholder approval is not an input that is indexed to the Company’s shares, the conversion feature is not indexed to the Company’s own stock. Therefore, the conversion feature does not qualify for the scope exception to derivative accounting and bifurcation is required at issuance. The fair value of the embedded derivative in the February 2023 Promissory Note was estimated using the intrinsic and discounted cash flow model at inception and on subsequent valuation dates. These models incorporate inputs such as the stock price of the Company and its debt yield. The fair value of the embedded derivative upon issuance was $1,323. The fair value of the February 2023 Promissory Note at issuance was $5,887, which was greater than the proceeds received. As such, the Company recorded the excess of fair value of the February 2023 Promissory Note over the proceeds received as interest expense in the amount of $987, which is reflected in the unaudited condensed consolidated statements of operations and comprehensive loss. In February 2023, Yorkville delivered Investor Notices requiring the Company to issue and sell an aggregate of 3,879,706 shares of common stock to Yorkville, in order to offset all outstanding amounts owed to Yorkville under the February 2023 Promissory Note. This resulted in a loss on debt extinguishment of $479 which is reflected in the unaudited condensed consolidated statements of operations and comprehensive loss. On March 17, 2023, the Company issued a convertible promissory note (the “March 2023 Promissory Note” and, together with the December 2022 Promissory Note and the February 2023 Promissory Note, the “Yorkville Convertible Promissory Notes”) with an aggregate principal amount of $15,000 in a private placement to Yorkville under a third supplemental agreement to the SEPA (the “Third Supplemental Agreement”). The March 2023 Promissory Note has a maturity date of August 17, 2023, was issued with an original issue discount of 2%, debt issuance costs of $64, and bears an annual interest rate of 5% which shall increase to an annual rate of 15% upon an Event of Default (as defined in the SEPA) for so long as it remains uncured. The March 2023 Promissory Note is convertible into shares of the Company’s common stock at a conversion price equal to the lower of $1.9368 or 92.5% of the lowest daily volume weighted average price of the Company’s common stock during the seven consecutive trading days immediately preceding the conversion date (the “Conversion Price”). The number of shares issuable upon conversion of the March 2023 Promissory Note is subject to the Exchange Cap limitation under the SEPA, unless shareholder approval is obtained. Because shareholder approval is not an input that is indexed to the Company’s shares, the conversion feature is not indexed to the Company’s own stock. Therefore, the conversion feature does not qualify for the scope exception to derivative accounting and bifurcation is required at issuance. The fair value of the March 2023 Promissory Note at issuance was $20,665, which was greater than the proceeds received. As such, the Company recorded the excess of fair value of the March 2023 Promissory Note over the proceeds received as interest expense in the amount of $5,965, which is reflected in the unaudited condensed consolidated statements of operations and comprehensive loss. The fair value of the embedded derivative upon issuance was $7,026. The fair value of the embedded derivative in the March 2023 Promissory Note was estimated using the intrinsic and discounted cash flow model at inception and on subsequent valuation dates. These models incorporate inputs such as the stock price of the Company and its debt yield. The assumptions used to determine the fair value of the embedded derivatives at issuance and at March 31, 2023 are as follows: March 17, 2023 March 31, 2023 EOSE Common Stock Price $ 2.24 $ 2.57 Debt Yield 40.00 % 40.00 % In March 2023, Yorkville delivered Investor Notices requiring the Company to issue and sell an aggregate of 5,383,174 shares of common stock to Yorkville, in order to offset a portion of outstanding amounts owed to Yorkville under the March 2023 Promissory Note. This resulted in a loss on debt extinguishment of $817 which is reflected in the unaudited condensed consolidated statements of operations and comprehensive loss. The carrying value of the March 2023 Promissory Note is as follows: March 31, 2023 Principal $ 6,000 Unamortized debt discount (545) Unamortized debt issuance costs (64) Embedded derivative liability 2,849 Aggregate carrying value $ 8,240 In April 2023, Yorkville delivered Investor Notices requiring the Company to issue and sell shares of common stock to Yorkville, in order to offset the remaining outstanding amounts owed to Yorkville under the March 2023 Promissory Note. See Note 19, Subsequent Events for additional information. 2021 Convertible Notes Payable – Related Party On July 6, 2021, the Company entered into an investment agreement with Spring Creek Capital, LLC, a wholly-owned, indirect subsidiary of Koch Industries, Inc. The investment agreement provides for the issuance and sale to Koch Industries of the 2021 Convertible Notes in the aggregate principal amount of $100,000. The maturity date of the 2021 Convertible Notes is June 30, 2026, subject to earlier conversion, redemption, or repurchase. The Company estimated the fair value of the embedded conversion feature using a binomial lattice model at inception and on subsequent valuation dates. This model incorporates inputs such as the stock price of the Company, dividend yield, risk-free interest rate, the effective debt yield and expected volatility. The effective debt yield and volatility involve unobservable inputs classified as Level 3 of the fair value hierarchy (refer to Note 14, Fair Value Measurement ). The assumptions used to determine the fair value of the embedded conversion feature are as follows: March 31, 2023 December 31, 2022 Term 3.25 years 3.5 years Dividend yield — % — % Risk-free interest rate 3.7 % 4.1 % Volatility 70.0 % 80.0 % Effective debt yield 40.0 % 25.0 % As of March 31, 2023 and December 31, 2022, the fair value of the embedded conversion feature was $1,684 and $918, respectively. The (loss) gain from the change in fair value of the embedded derivative conversion feature for the three months ended March 31, 2023 and 2022 amounted to $(766) and $7,695, respectively. Interest expense recognized on the 2021 Convertible Notes is as follows: Three months Ended March 31, 2023 2022 Contractual interest expense $ 1,637 $ 1,544 Amortization of debt discount 1,207 543 Amortization of debt issuance costs 117 87 Total $ 2,961 $ 2,174 The balances for the 2021 Convertible Notes are as follows: March 31, 2023 December 31, 2022 Principal $ 109,167 $ 109,167 Unamortized debt discount (23,526) (24,733) Unamortized debt issuance costs (2,286) (2,402) Embedded conversion feature 1,684 918 Aggregate carrying value $ 85,039 $ 82,950 As of March 31, 2023 and December 31, 2022, interest payable attributable to the 2021 Convertible Notes was $1,637 and $—, respectively. As of March 31, 2023, the Company was obligated to repay all contractual interest attributable to the 2021 Convertible Notes in-kind in accordance with the terms under the Senior Secured Term Loan (see below). Therefore, such interest was recorded as a long-term liability on the unaudited condensed consolidated balance sheets. AFG Convertible Notes - Related Party On January 18, 2023, the Company entered into the Investment Agreement with the Purchasers relating to the issuance and sale to the Purchasers of $13,750 in aggregate principal amount of the Company’s AFG Convertible Notes. Contractual Interest Rates - The AFG Convertible Notes will bear interest at a rate of 26.5% per annum, which shall be entirely paid-in-kind. All interest payments shall be made through an increase in the principal amount of the outstanding AFG Convertible Notes or through the issuance of additional notes (such interest is referred to herein as “PIK Interest”). Interest on the AFG Convertible Notes is payable semi-annually in arrears on June 30 and December 30, commencing on June 30, 2023. It is expected that the Notes will mature on June 30, 2026, subject to earlier conversion, redemption or repurchase. Conversion Rights - The AFG Convertible Notes are convertible at the option of the holder (the “Conversion Option”) at any time until the business day prior to the maturity date, including in connection with a redemption by the Company. The AFG Convertible Notes will be convertible into shares of the Company’s common stock, par value $0.0001 per share, based on an initial conversion price of approximately $1.67 per share subject to customary anti-dilution and other adjustments. As of March 31, 2023, 8,233,533 shares of the Company’s common stock were issuable upon conversion of the AFG Convertible Notes including the principal and interest payment in-kind. The Company has the right to settle conversions in shares of common stock, cash, or any combination thereof. Optional Redemption - On or after June 30, 2024, provided that the Company has obtained stockholder approval, the AFG Convertible Notes will be redeemable by the Company in the event that the closing sale price of the Company’s common stock has been at least 130% of the conversion price then in effect for at least 20 trading days (whether or not consecutive) during any 30 consecutive trading day period ending on, and including, the trading day immediately preceding the date on which the Company provides the redemption notice at a redemption price equal to the then current principal amount of the AFG Convertible Notes (inclusive of all PIK Interest), plus the aggregate amount of all interest payments on the AFG Convertible Notes that the holders of the AFG Convertible Notes to be redeemed would have been entitled to receive had the AFG Convertible Notes remained outstanding to the maturity date. Contingent Redemption - With certain exceptions, upon the occurrence of certain events and fundamental changes described in the AFG Convertible Notes Agreement, the holders of the AFG Convertible Notes may require that the Company repurchase all or part of the principal amount of the AFG Convertible Notes at a purchase price of 100% of the principal amount of the AFG Convertible Notes, plus accrued and unpaid interest. Embedded Derivative - The Conversion Option includes an exercise contingency, which requires the Company to obtain shareholder approval for conversions subject to the Exchange Cap. If shareholder approval is not obtained, following commercially reasonable efforts, the Company will be required to settle the conversion in excess of the Exchange Cap in cash. Since settlement in cash may be required in absence of shareholder approval, the embedded conversion feature fails the equity classification guidance in ASC 815 and is thus precluded from being classified in equity. Therefore, the embedded conversion feature is required to be bifurcated from the AFG Convertible Notes and accounted for at fair value at each reporting date, with changes in fair value recognized on the unaudited condensed consolidated statements of operations and comprehensive loss. The fair value of the embedded derivative upon issuance was $6,451. The embedded derivative is presented on the unaudited condensed consolidated balance sheet as a component of Convertible notes payable - related party. The loss from the change in fair value of the embedded derivative for the three months ended March 31, 2023 amounted to $10,272. The Company estimated the fair value of the embedded derivative using a binomial lattice model at the inception and on subsequent valuation dates. This model incorporates inputs such as the stock price of the Company, dividend yield, risk-free interest rate, the effective debt yield and expected volatility. The effective debt yield and volatility involve unobservable inputs classified as Level 3 of the fair value hierarchy (see Note 14, Fair Value Measurement for further discussion). The assumptions used to determine the fair value of the embedded derivative as of March 31, 2023 and as of the date of issuance are as follows: March 31, 2023 January 18, 2023 Term 3.25 years 3.5 years Dividend yield — % — % Risk-free interest rate 3.7 % 3.6 % Volatility 70.0 % 70.0 % Effective debt yield 40.0 % 40.0 % The fair value of the AFG Convertible Notes at issuance was $16,623, which was greater than the proceeds received. The Company recorded the difference of $2,873 as interest expense on the unaudited condensed consolidated statement of operations and comprehensive loss. Interest expense recognized on the AFG Convertible Notes is as follows: Three Months Ended Contractual interest expense $ 779 Amortization of debt discount 148 Amortization of debt issuance costs 42 Total $ 969 The balance for the AFG Convertible Notes is as follows: March 31, 2023 Principal $ 13,750 Unamortized debt discount (3,430) Unamortized debt issuance costs (968) Embedded conversion feature 16,723 Aggregate carrying value $ 26,075 Senior Secured Term Loan On July 29, 2022, the Company entered into a $100,000 Senior Secured Term Loan Credit Agreement with Atlas Credit Partners (ACP) Post Oak Credit I LLC., as administrative agent for the lenders and collateral agent for the secured parties. As of March 31, 2023, the Company had total borrowings of $100,000 under the Senior Secured Term Loan. The Senior Secured Term Loan is scheduled to mature on the earlier of (i) July 29, 2026, and (ii) 91 days prior to the current maturity date of the 2021 Convertible Notes of June 30, 2026. The Company has the right at any time to prepay any Borrowing in whole or in part in an amount of not less than $500. The outstanding principal balance of the Senior Secured Term Loan bears interest, at the applicable margin plus, at the Company’s election, either (i) the benchmark secured overnight financing rate (“SOFR”), which is a per annum rate equal to (y) the Adjusted Term SOFR (as defined in the agreement) plus 0.2616%, or (ii) the alternate base rate (“ABR”), which is a per annum rate equal to the greatest of (x) the Prime Rate (as defined in the agreement), (y) the NYFRB Rate (as defined in the agreement) plus 0.5% and (z) the SOFR. The applicable margin under the Credit Agreement is 8.5% per annum with respect to SOFR loans, and 7.5% per annum with respect to ABR loans. Interest on the Senior Secured Term Loan accrues at a variable interest rate, and interest payments are due quarterly. The Company may elect to convert SOFR Loans to ABR (and ABR Loans to SOFR). As of March 31, 2023, the interest rate in effect for the Senior Secured Term Loan for the first quarter of 2023 interest payment was 13.66%. Any repayment of principal prior to the second anniversary of the issuance date is subject to a call premium. The call premium is equal to the present value of all interest payments due through June 30, 2024, calculated using a discount rate equal to the applicable treasury rate as of the repayment date plus 50 basis points. The Company deemed that the fair value of the embedded derivative features which qualify for bifurcation was de minimis. Concurrently, the Company entered into a Guarantee and Collateral Agreement which secures and guarantees the Senior Secured Term Loan with substantially all the assets of the Company and its subsidiaries, other than the Company’s equity interests in Hi-Power and assets of Hi-Power. Additionally, interest is required to be escrowed in an amount equal to the aggregate amount of the four immediately following interest payments owed on the Loans which was $11,450 at March 31, 2023. This escrowed and restricted cash is presented on a separate line item on the unaudited condensed consolidated balance sheets as long-term restricted cash. The agreements also contain customary affirmative and negative covenants. They limit the Company’s and its subsidiaries’ ability to incur indebtedness, make restricted payments, including cash dividends on its common stock, make certain investments, loans and advances, enter into mergers and acquisitions, sell, assign, transfer or otherwise dispose of its assets, enter into transactions with its affiliates and engage in sale and leaseback transactions, among other restrictions. Furthermore, the limitation on the Company’s ability to incur indebtedness also (i) limits the amount of Pre-Advance Loans that the Company may have outstanding at any time to $15,000 under the SEPA and (ii) requires the payment of principal and interest in kind on each of the Pre-Advance Loans (if any) and the 2021 Convertible Notes. While the Company was in compliance with this covenant as of March 31, 2023 and currently expects to remain in compliance as of June 30, 2023, absent the Company’s ability to secure additional outside capital, the Company may be unable to remain in compliance with this covenant beginning on September 30, 2023 and thereafter (see Note 1, Overview for further discussion). The following table summarizes interest expense recognized: Three Months Ended March 31, 2023 Contractual interest expense $ 3,373 Amortization of debt discount 93 Amortization of debt issuance costs 822 Total $ 4,288 The Senior Secured Term Loan balance is as follows: March 31, 2023 December 31, 2022 Principal $ 100,000 $ 100,000 Unamortized debt discount (1,773) (1,866) Unamortized debt issuance costs (15,696) (16,518) Aggregate carrying value $ 82,531 $ 81,616 Equipment Financing facility The Company entered into an agreement on September 30, 2021 with Trinity Capital Inc. (“Trinity”) for a $25,000 equipment financing facility, the proceeds of which will be used to acquire certain manufacturing equipment, subject to Trinity’s approval. Each draw is executed under a separate payment schedule (a “Schedule”) that constitutes a separate financial instrument. The financing fees included in each Schedule are established through monthly payment factors determined by Trinity. Such monthly payment factors are based on the Prime Rate reported in The Wall Street Journal in effect on the first day of the month in which a Schedule is executed. Date of Draw Gross Amount of Initial Draw Coupon Interest Rate Debt Issuance Costs September 2021 $ 7,000 14.3% $ 175 September 2022 4,216 16.2% 96 Total Equipment Financing loans $ 11,216 $ 271 On September 30, 2022, the equipment facility’s unused commitment of $13,784 expired. As of March 31, 2023 and December 31, 2022, total equipment financing debt outstanding was $7,900 and $8,577, respectively of which $2,981 and $2,872 are recorded as a current liability on the unaudited condensed consolidated balance sheets, respectively. For the three months ended March 31, 2023 and 2022, the Company recognized $317 and $219 as interest expense attributable to the equipment financing agreement, respectively.

Warrants Liability - Related Pa

Warrants Liability - Related Party	3 Months Ended
Warrants Liability - Related Party	Mar. 31, 2023
Other Liabilities Disclosure [Abstract]
Warrants Liability - Related Party	Warrants Liability - Related Party Private placement warrants issued to the Sponsor of BMRG in its initial public offering on May 22, 2020 became exercisable on May 22, 2021. These warrants are classified as Level 2 financial instruments in the fair value hierarchy (refer to Note 15, Fair Value Measurement ). They are valued on the basis of the quoted price of the Company’s public warrants, adjusted for insignificant difference between the public warrants and the private placement warrants. As of March 31, 2023 and December 31, 2022, 325,000 private placement warrants were outstanding with a fair value of $234 and $78, respectively. The change in fair value for the three months ended March 31, 2023 and 2022 amounted to $156 and $567, respectively. The change has been recognized in (loss) gain on change in fair value of derivatives - related parties in the Company’s unaudited condensed consolidated statements of operations and comprehensive loss.

Fair Value Measurement

Fair Value Measurement	3 Months Ended
Fair Value Measurement	Mar. 31, 2023
Fair Value Disclosures [Abstract]
Fair Value Measurement	Fair Value Measurement The Company’s financial instruments consist of cash and cash equivalents, restricted cash, private placement warrants, accounts receivable, notes receivable, contract assets, accounts payable, note payable, convertible notes payable — related party, contract liabilities and long-term debt. Accounting standards establish a hierarchy, which prioritizes the inputs to valuation techniques used to measure fair value into three levels. The fair value hierarchy gives the highest priority to quoted market prices (unadjusted) in active markets for identical assets or liabilities (Level 1) and the lowest priority to unobservable inputs (Level 3). Level 2 inputs are inputs other than quoted prices included within Level 1 that are observable for the asset or liability, either directly or indirectly. Accounting standards require financial assets and liabilities to be classified based on the lowest level of input that is significant to the fair value measurement. The Company’s assessment of the significance of a particular input to the fair value measurement requires judgment and the exercise of this judgment may affect the valuation of the fair value of assets and liabilities and their placement within the fair value hierarchy levels. The carrying value of cash and cash equivalents, restricted cash, accounts receivable, contract assets, contract liabilities and accounts payable are considered to be representative of their fair value due to the short maturity of these instruments. The table below summarizes the fair values of certain liabilities that are included within the Company’s accompanying unaudited condensed consolidated balance sheets, and their designations among the three fair value measurement categories: March 31, 2023 December 31, 2022 Level 1 Level 2 Level 3 Level 1 Level 2 Level 3 Liabilities Private placement warrants $ — $ 234 $ — $ — $ 78 $ — Embedded derivative liabilities $ — $ — $ 21,255 $ — $ — $ 1,945 The following table presents a roll-forward of the activity of the embedded derivative liabilities within the convertible notes discussed in Note 12, Borrowings . These liabilities were measured at fair value on a recurring basis using significant unobservable inputs (Level 3). Three Months Ended March 31, 2023 2022 Balance at beginning of the period $ 1,945 $ 12,359 Additions 14,799 — Extinguishment from Yorkville Promissory Notes Conversions (8,423) — Change in fair value included in earnings 12,934 (7,695) Balance at end of the period $ 21,255 $ 4,664 The estimated fair value of financial instruments not carried at fair value in the unaudited condensed consolidated balance sheets was as follows: Level in Fair Value Hierarchy March 31, 2023 December 31, 2022 Carrying Value Fair Value Carrying Value Fair Value Notes receivable 3 $ 862 $ 688 $ 863 $ 677 AFG Convertible Notes* 3 26,075 27,593 — — 2021 Convertible Notes* 3 85,039 46,634 82,950 62,421 Senior Secured Term Loan 3 82,531 67,410 81,616 77,576 Equipment financing facility 3 7,900 4,045 8,577 6,282 Yorkville Convertible Notes* 3 8,240 8,375 2,688 2,908 Total $ 210,647 $ 154,745 $ 176,694 $ 149,864 *Includes the embedded derivative liabilities.

Commitments and Contingencies

Commitments and Contingencies	3 Months Ended
Commitments and Contingencies	Mar. 31, 2023
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies Lease Commitments The Company has lease commitments under lease agreements. As of March 31, 2023, future lease payments amounted to $5,897. Minimum Volume Commitment In June 2022, the Company entered into a long-term supply agreement with a minimum volume commitment with a third party, which provides services to process certain raw materials. Any purchase order issued under this supply agreement will be non-cancellable. To the extent the Company fails to order the guaranteed minimum volume defined in the contract at the end of the term, the Company is required to pay the counterparty an amount equal to the shortfall, if any, multiplied by a fee. As of March 31, 2023, the Company had open purchase commitments of $200 under this agreement. The Company believes that the probability of failing to meet the minimum volume commitment is remote and no shortfall penalty has been accrued as of March 31, 2023. Legal Proceedings Department of Justice On July 7, 2022, the Company entered into a settlement agreement with the U.S. Department of Justice (the “DOJ”) and Vincent Icolari (“Relator”) to resolve the previously disclosed investigation by the DOJ for underpayment of certain custom duties in past years in connection with imports of batteries and battery components manufactured abroad. The investigation resulted from a qui tam lawsuit (the “Civil Action”) filed by the Relator in December 2019 alleging violations of the False Claims Act. Pursuant to the terms of the settlement agreement, the Company has agreed to pay a total of $1,017 to the United States Department of Justice and $70 to Relator’s counsel. Upon receipt of such payments, the DOJ and the Relator have agreed to release the Company from civil monetary and administrative claims under the False Claims Act and the Relator has agreed to release the Company from any claims related to the Civil Action. The Company has fully settled this liability. Delaware Section 205 Petition On November 12, 2020, B. Riley Principal Merger Corp. II (“BMRG”), the predecessor to the Company, held a special meeting of stockholders (the “BMRG Special Meeting”) to approve certain matters relating to the business combination between BMRG and Eos Energy Storage LLC. One of these matters was a proposal to amend and restate BMRG’s certificate of incorporation in order to, among other things, increase the number of authorized shares of common stock from 125,000,000 shares of common stock, consisting of 100,000,000 shares of Class A common stock and 25,000,000 shares of Class B common stock, to 200,000,000 shares of common stock, and to reclassify all Class A common stock and Class B common stock as a single class of common stock (the “Charter Amendment Proposal”). The Charter Amendment Proposal was approved by a majority of the outstanding shares of Class A common stock and Class B common stock of BMRG as of the record date for the BMRG Special Meeting, voting together as a single class, although voting records indicate that a majority of each of the shares of Class A common stock and Class B common stock also approved the Charter Amendment Proposal. After the BMRG Special Meeting, BMRG and Eos Energy Storage LLC closed the business combination and the Company’s certificate of incorporation, as amended to give effect to the Charter Amendment Proposal, became effective. A recent ruling by the Delaware Court of Chancery introduced uncertainty as to whether Section 242(b)(2) of the Delaware General Corporation Law (the “DGCL”) would have required the Charter Amendment Proposal to be approved by separate votes of the majority of BMRG’s then-outstanding shares of Class A common stock and Class B common stock. To resolve potential uncertainty with respect to the Company’s capital structure, the Company filed a petition in the Delaware Court of Chancery under Section 205 of the DGCL to seek validation of the Charter Amendment Proposal. Section 205 of the DGCL permits the Court of Chancery, in its discretion, to ratify and validate potentially defective corporate acts. On February 27, 2023, the Court of Chancery approved the Company’s request for relief and entered an order under Section 205 of the Delaware General Corporation Law (1) declaring the Company’s Third Amended and Restated Certificate of Incorporation (the “Charter”), including the filing and effectiveness thereof, as validated and effective retroactive to the date of its filing with the Office of the Secretary of State of the State of Delaware on November 16, 2020, and all amendments effected thereby and (2) ordering that the Company’s securities (and the issuance of the securities) described in the Petition and any other securities issued in reliance on the validity of the Charter are validated and declared effective, each as of the original issuance dates. Class Action Complaint On March 8, 2023, Plaintiff Richard Delman filed a class action complaint (the “Complaint”) in the Court of Chancery of the State of Delaware. The Complaint names certain of the Company’s former directors as defendants. Neither the Company nor Eos Energy Storage LLC was named as a defendant in the Complaint, but each was identified as a relevant non-party and the Company owes certain indemnification obligations relating to the lawsuit to the Company’s former directors.

Stock-Based Compensation

Stock-Based Compensation	3 Months Ended
Stock-Based Compensation	Mar. 31, 2023
Share-Based Payment Arrangement [Abstract]
Stock-Based Compensation	Stock-Based Compensation Our stock-based compensation expense is associated with restricted stock units (“RSU”s) and stock options. Stock-based compensation expense is recognized on a straight-line basis over the requisite service period of the award, which is generally the award vesting term. Stock options generally have a term of five three Three months ended 2023 2022 Stock options $ 740 $ 911 Restricted stock units 2,623 3,032 Total $ 3,363 $ 3,943 The stock compensation expense has been recorded in cost of goods sold, research and development expenses, and selling, general and administrative expenses.

Income Taxes

Income Taxes	3 Months Ended
Income Taxes	Mar. 31, 2023
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes For the three months ended March 31, 2023 and 2022, income tax expense (benefit) was $10 and $(42), respectively, related to taxable earnings from the Company’s foreign operations. The income tax expense differs from the amount computed by applying the statutory U.S. federal income tax rate of 21% to the loss before income taxes. This is due to non-taxable income, foreign operations, and pre-tax losses for which no tax benefit can be recognized for U.S. income tax purposes. The Company estimates and applies the annual effective tax rate to its ordinary earnings each interim period. Any significant unusual or infrequent items, if any, are not included in the estimation of the annual effective tax rate. Rather, these items and their related income tax expense are separately stated in the interim period in which they occur. The quarterly estimate of the annual effective tax rate and related tax expense is subject to variation due to a multitude of factors. Factors may include, but are not limited to, the inability to accurately predict the Company’s pre-tax and taxable income and loss. At each balance sheet date, management assesses the likelihood that the Company will be able to realize its deferred tax assets. Management considered all available positive and negative evidence in assessing the need for a valuation allowance. The realization of deferred tax assets depends on the generation of sufficient taxable income of the appropriate character and in the appropriate taxing jurisdiction during the future periods in which the related temporary differences become deductible. Management has determined that it is unlikely that the Company will be able to utilize its U.S. deferred tax assets at March 31, 2023 and December 31, 2022 due to cumulative losses. Therefore, the Company has a valuation allowance against its net deferred tax assets. As of March 31, 2023 and December 31, 2022, the Company has unrecognized tax benefits associated with uncertain tax positions that, if recognized, would not affect the effective tax rate on income from continuing operations. The Company is not currently under examination by any taxing jurisdiction, and none of the uncertain tax positions are expected to reverse within the next 12 months. The Company files income tax returns in U.S. federal and various state jurisdictions, as well as Italy and India. The open tax years for federal returns are 2019 and forward, and open tax years for state returns are generally 2018 and forward. In addition, net operating losses generated in closed years and utilized in open years are subject to adjustment by the tax authorities. On August 16, 2022, President Biden signed the Inflation Reduction Act of 2022 into law. There are two major corporate tax provisions included in the Act. In general, the IRA creates a 15% corporate alternative minimum tax (“CAMT”) on any corporation that has (or has had) average annual “adjusted financial statement income” for a three-year period preceding the tax year that exceeds $1 billion. The CAMT is effective for tax years beginning after December 31, 2022. The IRA also imposes on publicly traded U.S. corporations a 1% excise tax on certain repurchases of their stock. The excise tax is effective for stock repurchases after December 31, 2022. The Company does not expect the aforementioned provisions in the IRA to have any material impact on the Company’s unaudited condensed consolidated financial statements. In addition to the CAMT discussed above, the IRA has production tax credits that are discussed in Note 10, Government Grants.

Shareholders_ Deficit

Shareholders’ Deficit	3 Months Ended
Shareholders’ Deficit	Mar. 31, 2023
Equity [Abstract]
Shareholders’ Deficit	Shareholders’ Deficit Preferred Shares The Company is authorized to issue 1,000,000 shares of preferred stock with such designations, voting and other rights and preferences as may be determined from time to time by the Company’s Board of Directors. At March 31, 2023 and December 31, 2022, there were no shares of preferred stock issued or outstanding. Common Stock On June 28, 2022, the Company’s shareholders approved an amendment to the Company’s Third Amended and Restated Certificate of Incorporation to increase the authorized shares of common stock with $0.0001 par value from 200,000,000 to 300,000,000. The holders of the Company’s common stock are entitled to one vote for each share. At March 31, 2023 and December 31, 2022, there were 95,222,670 and 82,653,781 shares of common stock issued and outstanding. Treasury Stock For the three months ended March 31, 2023 and 2022, the Company recorded treasury stock of $345 and $826 for shares withheld from employees to cover the payroll tax liability of RSUs vested, respectively. The treasury stock was immediately retired. Public Warrants The Company sold warrants to purchase 9,075,000 shares of the Company’s common stock in a public offering and a private placement on May 22, 2020. Each warrant entitles the holder to purchase a share of common stock at a price of $11.50 per share. For the three months ended March 31, 2022, 600 public warrants were exercised. There were no public warrants exercised for the three months ended March 31, 2023. As of March 31, 2023 and December 31, 2022, there were 7,001,654 public warrants outstanding. Standby Equity Purchase Agreement On April 28, 2022, the Company entered into the SEPA with Yorkville. Pursuant to the SEPA, as amended, the Company has the right, but not the obligation, to sell to Yorkville up to $75,000 of shares of its common stock at the Company’s request at any time during the commitment period, which commenced on April 28, 2022 and will end on the earlier of (i) May 1, 2024, or (ii) the date on which Yorkville shall have made payment of advances requested by the Company totaling up to the commitment amount of $75,000. Each sale the Company requests under the SEPA (an “Advance”) may be for a number of shares of common stock with an aggregate value of up to $20,000. The SEPA provides for shares to be sold to Yorkville at 97.0% of market price. Subject to the mutual consent of Yorkville and the Company, from time to time the Company may request, and Yorkville shall provide, pre-advance loans (each, a “Pre-Advance Loan”) each in the principal amount not to exceed $50,000, pursuant to a promissory note on terms and conditions to be agreed by both parties. In addition to the Yorkville Convertible Promissory Notes issued under the SEPA as discussed in Note 12, Borrowings, on March 14, 2023, the Company also issued 683,908 shares pursuant to the SEPA and raised $1,250 of cash from the offering. For the three months ended March 31, 2023, total funds raised under the SEPA, inclusive of proceeds received from the Yorkville Convertible Promissory Notes, were $20,850. Shares issued pursuant to the Yorkville Convertible Promissory Notes for the three months ended March 31, 2023 were 11,216,492. Additionally, shares issued under the SEPA for the three months ended March 31, 2023 were 683,908. At-the-Market Offering Program On August 5, 2022, the Company entered into the Sales Agreement with Cowen and Company LLC (“Cowen”), with respect to an ATM offering program under which the Company may offer and sell, from time to time at its sole discretion, shares of its common stock, par value $0.0001 per share, having an aggregate offering price of up to $100,000 (the “Placement Shares”) through Cowen as its sales agent and/or principal. The Company will pay Cowen a commission equal to 3.0% of the gross sales proceeds of any Placement Shares sold. The Company will also reimburse Cowen for certain expenses incurred in connection with the Sales Agreement. The Sales Agreement will terminate upon the earlier of (i) the sale of all Placement Shares subject to the Sales Agreement or (ii) termination of the Sales Agreement in accordance with the terms and conditions set forth therein. There were no shares issued under the ATM offering program for the three months ended March 31, 2023. Earnings (Loss) Per Share Basic earnings per share (“EPS”) is computed by dividing earnings available to common shareholders by the weighted average number of shares of common stock outstanding during the period. Other potentially dilutive common shares, and the related impact to earnings, are considered when calculating EPS on a diluted basis. As the Company incurred a net loss for the three months ended March 31, 2023 and 2022, the potential dilutive shares from stock options, restricted stock units, warrants, and convertible redeemable notes were excluded from the calculation of diluted net loss per share because their effect would have been anti-dilutive for the periods presented. Therefore, basic and diluted EPS are computed using the same number of weighted average shares for the three months ended March 31, 2023 and 2022. The following potentially dilutive shares were excluded from the calculation of diluted net loss per share because their effect would have been anti-dilutive for the periods presented: For the Three Months Ended March 31, 2023 2022 Stock options and restricted stock units 6,987,945 4,784,076 Public and private placement warrants 7,326,654 7,326,654 Convertible Notes (if converted) 16,950,606 5,144,074

Subsequent Events

Subsequent Events	3 Months Ended
Subsequent Events	Mar. 31, 2023
Subsequent Events [Abstract]
Subsequent Events	Subsequent Events Yorkville In April, Yorkville delivered Investor Notices requiring the Company to issue and sell an aggregate of 3,258,744 shares of common stock to Yorkville, in order to offset the remaining $6,000 owed to Yorkville under the March 2023 Promissory Note. On April 10, 2023, the Company issued and sold a convertible promissory note (the “April 2023 Promissory Note”) with an aggregate principal amount of $15,000 in a private placement to Yorkville under the SEPA. The April 2023 Promissory Note has a maturity date of August 31, 2023, was issued with an original issue discount of 2%, and bears an annual interest rate of 5% which shall increase to an annual rate of 15% upon an Event of Default (as defined in the SEPA) for so long as it remains uncured. The April 2023 Promissory Note is convertible into shares of the Company’s common stock at a conversion price equal to the lower of $2.8093 or 90% of the lowest daily volume weighted average price of the Company’s common stock during the seven consecutive trading days immediately preceding the conversion date. In April, 2023, Yorkville delivered Investor Notices requiring the Company to issue and sell an aggregate of 1,349,926 shares of common stock to Yorkville, in order to offset a portion of the outstanding amounts owed to Yorkville under the April 2023 Promissory Note. Equity and Warrant Issuance On April 12, 2023, the Company entered into a securities purchase agreement (the “Purchase Agreement”) for the issuance and sale of an aggregate of 16,000,000 shares of the Company’s common stock at a purchase price of $2.50 per share in a registered direct offering (the “Offering”). The Company has also agreed to issue in a concurrent private placement unregistered warrants to purchase up to an aggregate of 16,000,000 shares of common stock. The warrants have an exercise price of $3.14 per share, are not exercisable until six months from the date of issuance, and will expire 5.5 years from the date of issuance. The gross proceeds to the Company from the Offering were $40,000, before deducting advisory fees and other offering expenses payable by the Company.

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	3 Months Ended
Summary of Significant Accounting Policies (Policies)	Mar. 31, 2023
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation The accompanying unaudited condensed consolidated financial statements include the accounts of the Company and its 100% owned, direct and indirect subsidiaries and have been prepared in accordance with U.S. generally accepted accounting principles (“GAAP”). All intercompany transactions and balances have been eliminated in the preparation of the unaudited condensed consolidated financial statements. These statements reflect all adjustments, consisting of normal recurring adjustments, which, in the opinion of management, are necessary for fair presentation of the information contained therein. Certain information and footnote disclosures normally included in financial statements prepared in accordance with GAAP have been condensed or omitted pursuant to the rules and regulations of the U.S. Securities and Exchange Commission (“SEC”). The interim financial statements should be read in conjunction with the audited consolidated financial statements, including the notes thereto, included in our 2022 Annual Report on Form 10-K. These interim results are not necessarily indicative of results for the full year.
Use of Estimates	Use of Estimates The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amount of revenues and expenses during the reporting period. Actual results could differ from those estimates.
Reclassification of Prior Year Presentation	Reclassification of Prior Year PresentationCertain prior year amounts have been reclassified for consistency with the current year presentation. These reclassifications had no effect on the reported results of operations.
Recent Accounting Pronouncements	Recent Accounting Pronouncements There were no new accounting standards or updates during the three months ended March 31, 2023 that would have a material impact on the Company’s unaudited condensed consolidated financial statements.

Revenue Recognition (Tables)

Revenue Recognition (Tables)	3 Months Ended
Revenue Recognition (Tables)	Mar. 31, 2023
Revenue from Contract with Customer [Abstract]
Schedule of Revenue Recognition	Product revenues, which are generally recognized at a point in time, and service revenues, which are generally recognized over time, are as follows: For the Three Months Ended March 31, 2023 2022 Product revenue $ 8,675 $ 3,293 Service revenue 160 5 Total revenues $ 8,835 $ 3,298
Schedule of Information about Contract Liabilities from Contracts with Customers	The following table provides information about contract assets and contract liabilities from contracts with customers. Contract assets, current and contract liabilities, current and long-term are included separately on the unaudited condensed consolidated balance sheets and contract assets, long-term are included under other assets, net. March 31, December 31, Contract assets $ 3,914 $ 2,000 Contract liabilities $ 1,356 $ 4,806

Cash, Cash Equivalents and Re_2

Cash, Cash Equivalents and Restricted Cash (Tables)	3 Months Ended
Cash, Cash Equivalents and Restricted Cash (Tables)	Mar. 31, 2023
Cash and Cash Equivalents [Abstract]
Schedule of Cash, Cash Equivalents, and Restricted Cash	The following table reconciles reported amounts from the unaudited condensed consolidated balance sheets to cash, cash equivalents and restricted cash reported within the unaudited condensed consolidated statements of cash flows: March 31, March 31, Cash and cash equivalents $ 16,127 $ 55,361 Restricted cash (1) 2,725 — Long-term restricted cash 11,450 1,255 Total cash, cash equivalents, and restricted cash $ 30,302 $ 56,616
Schedule of Cash, Cash Equivalents, and Restricted Cash	The following table reconciles reported amounts from the unaudited condensed consolidated balance sheets to cash, cash equivalents and restricted cash reported within the unaudited condensed consolidated statements of cash flows: March 31, March 31, Cash and cash equivalents $ 16,127 $ 55,361 Restricted cash (1) 2,725 — Long-term restricted cash 11,450 1,255 Total cash, cash equivalents, and restricted cash $ 30,302 $ 56,616

Inventory (Tables)

Inventory (Tables)	3 Months Ended
Inventory (Tables)	Mar. 31, 2023
Inventory Disclosure [Abstract]
Schedule of Components of Inventories	The following table provides information about inventory balances: March 31, December 31, Raw materials $ 13,896 $ 22,899 Work-in-process 64 361 Finished goods 115 — Total inventory, net $ 14,075 $ 23,260

Property, Plant and Equipment_2

Property, Plant and Equipment, Net (Tables)	3 Months Ended
Property, Plant and Equipment, Net (Tables)	Mar. 31, 2023
Property, Plant and Equipment [Abstract]
Schedule of Components of Property, Plant and Equipment, Net	The following table provides information about property, plant and equipment, net balances: Estimated Useful lives March 31, December 31, Equipment 5 to 10 years $ 23,622 $ 23,653 Finance lease 5 years 379 379 Furniture 5 to 10 years 1,892 1,868 Leasehold improvements Lesser of useful life/ 6,629 6,303 Tooling 2 to 3 years 6,654 6,926 Total 39,176 39,129 Less: Accumulated depreciation (14,559) (11,960) Total property, plant and equipment, net $ 24,617 $ 27,169

Accrued Expenses (Tables)

Accrued Expenses (Tables)	3 Months Ended
Accrued Expenses (Tables)	Mar. 31, 2023
Payables and Accruals [Abstract]
Schedule of Accrued Expenses	Accrued expenses were as follows: March 31, December 31, Accrued payroll $ 4,636 $ 2,706 Warranty reserve (1) 3,972 3,836 Accrued legal and professional expenses 2,087 840 Provision for contract losses 1,936 2,561 Insurance premium payable, current 2,730 2,607 Other 4,990 2,809 Total accrued expenses $ 20,351 $ 15,359 (1) Refer to the table below for the warranty reserve activity for the three months ended March 31, 2023.
Schedule of Warranty Reserve Activity	The following table summarizes warranty reserve activity: Three Months Ended 2023 2022 Warranty reserve - beginning of period $ 3,836 $ 2,112 Additions for current period deliveries 357 673 Changes in the warranty reserve estimate — 955 Warranty costs incurred (221) (500) Warranty reserve - end of period $ 3,972 $ 3,240

Borrowings (Tables)

Borrowings (Tables)	3 Months Ended
Borrowings (Tables)	Mar. 31, 2023
Debt Disclosure [Abstract]
Schedule of Long Term Debt	The Company’s debt obligations at carrying value consist of the following related and third-party borrowings: March 31, 2023 December 31, 2022 Borrowing Outstanding Carrying Value* Borrowing Outstanding Carrying Value* Yorkville Convertible Promissory Note - due August 2023 $ 6,000 $ 8,240 $ 2,000 $ 2,688 2021 Convertible Notes Payable - due June 2026 109,167 85,039 109,167 82,950 AFG Convertible Note - due June 2026 13,750 26,075 — — Senior Secured Term Loan - due March 2026 100,000 82,531 $ 100,000 $ 81,616 Equipment financing facility - due April 2025 7,900 7,900 8,577 8,577 Total borrowings 236,817 209,785 219,744 175,831 Current portion 11,221 11,221 5,560 5,560 Total borrowings, non-current $ 225,596 $ 198,564 $ 214,184 $ 170,271 * Carrying value includes unamortized deferred financing costs, unamortized discounts, and fair value of embedded derivative liabilities. The Senior Secured Term Loan balance is as follows: March 31, 2023 December 31, 2022 Principal $ 100,000 $ 100,000 Unamortized debt discount (1,773) (1,866) Unamortized debt issuance costs (15,696) (16,518) Aggregate carrying value $ 82,531 $ 81,616 Date of Draw Gross Amount of Initial Draw Coupon Interest Rate Debt Issuance Costs September 2021 $ 7,000 14.3% $ 175 September 2022 4,216 16.2% 96 Total Equipment Financing loans $ 11,216 $ 271
Schedule of Fair Value of Embedded Derivatives	The assumptions used to determine the fair value of the embedded derivatives at issuance and at March 31, 2023 are as follows: March 17, 2023 March 31, 2023 EOSE Common Stock Price $ 2.24 $ 2.57 Debt Yield 40.00 % 40.00 %
Schedule of Balances Recognized upon Issuance of Convertible Notes	The carrying value of the March 2023 Promissory Note is as follows: March 31, 2023 Principal $ 6,000 Unamortized debt discount (545) Unamortized debt issuance costs (64) Embedded derivative liability 2,849 Aggregate carrying value $ 8,240 The balances for the 2021 Convertible Notes are as follows: March 31, 2023 December 31, 2022 Principal $ 109,167 $ 109,167 Unamortized debt discount (23,526) (24,733) Unamortized debt issuance costs (2,286) (2,402) Embedded conversion feature 1,684 918 Aggregate carrying value $ 85,039 $ 82,950 The balance for the AFG Convertible Notes is as follows: March 31, 2023 Principal $ 13,750 Unamortized debt discount (3,430) Unamortized debt issuance costs (968) Embedded conversion feature 16,723 Aggregate carrying value $ 26,075
Schedule of Assumptions Used to Determine Fair Value of Embedded Conversion Feature	The assumptions used to determine the fair value of the embedded conversion feature are as follows: March 31, 2023 December 31, 2022 Term 3.25 years 3.5 years Dividend yield — % — % Risk-free interest rate 3.7 % 4.1 % Volatility 70.0 % 80.0 % Effective debt yield 40.0 % 25.0 % March 31, 2023 January 18, 2023 Term 3.25 years 3.5 years Dividend yield — % — % Risk-free interest rate 3.7 % 3.6 % Volatility 70.0 % 70.0 % Effective debt yield 40.0 % 40.0 %
Schedule of Interest Expense	Interest expense recognized on the 2021 Convertible Notes is as follows: Three months Ended March 31, 2023 2022 Contractual interest expense $ 1,637 $ 1,544 Amortization of debt discount 1,207 543 Amortization of debt issuance costs 117 87 Total $ 2,961 $ 2,174 Interest expense recognized on the AFG Convertible Notes is as follows: Three Months Ended Contractual interest expense $ 779 Amortization of debt discount 148 Amortization of debt issuance costs 42 Total $ 969 The following table summarizes interest expense recognized: Three Months Ended March 31, 2023 Contractual interest expense $ 3,373 Amortization of debt discount 93 Amortization of debt issuance costs 822 Total $ 4,288

Fair Value Measurement (Tables)

Fair Value Measurement (Tables)	3 Months Ended
Fair Value Measurement (Tables)	Mar. 31, 2023
Fair Value Disclosures [Abstract]
Schedule of Fair Value of Liabilities	The table below summarizes the fair values of certain liabilities that are included within the Company’s accompanying unaudited condensed consolidated balance sheets, and their designations among the three fair value measurement categories: March 31, 2023 December 31, 2022 Level 1 Level 2 Level 3 Level 1 Level 2 Level 3 Liabilities Private placement warrants $ — $ 234 $ — $ — $ 78 $ — Embedded derivative liabilities $ — $ — $ 21,255 $ — $ — $ 1,945
Schedule of Liabilities Measured at Fair Value	The following table presents a roll-forward of the activity of the embedded derivative liabilities within the convertible notes discussed in Note 12, Borrowings . These liabilities were measured at fair value on a recurring basis using significant unobservable inputs (Level 3). Three Months Ended March 31, 2023 2022 Balance at beginning of the period $ 1,945 $ 12,359 Additions 14,799 — Extinguishment from Yorkville Promissory Notes Conversions (8,423) — Change in fair value included in earnings 12,934 (7,695) Balance at end of the period $ 21,255 $ 4,664
Fair Value, Liabilities Measured on Recurring Basis	The estimated fair value of financial instruments not carried at fair value in the unaudited condensed consolidated balance sheets was as follows: Level in Fair Value Hierarchy March 31, 2023 December 31, 2022 Carrying Value Fair Value Carrying Value Fair Value Notes receivable 3 $ 862 $ 688 $ 863 $ 677 AFG Convertible Notes* 3 26,075 27,593 — — 2021 Convertible Notes* 3 85,039 46,634 82,950 62,421 Senior Secured Term Loan 3 82,531 67,410 81,616 77,576 Equipment financing facility 3 7,900 4,045 8,577 6,282 Yorkville Convertible Notes* 3 8,240 8,375 2,688 2,908 Total $ 210,647 $ 154,745 $ 176,694 $ 149,864 *Includes the embedded derivative liabilities.

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	3 Months Ended
Stock-Based Compensation (Tables)	Mar. 31, 2023
Share-Based Payment Arrangement [Abstract]
Schedule of Stock-based Compensation Expense	Stock-based compensation expense included in the unaudited condensed consolidated statements of operations and comprehensive loss was as follows: Three months ended 2023 2022 Stock options $ 740 $ 911 Restricted stock units 2,623 3,032 Total $ 3,363 $ 3,943

Shareholders_ Deficit (Tables)

Shareholders’ Deficit (Tables)	3 Months Ended
Shareholders’ Deficit (Tables)	Mar. 31, 2023
Equity [Abstract]
Schedule of Antidilutive Shares Excluded from Calculation of Earnings Per Share	The following potentially dilutive shares were excluded from the calculation of diluted net loss per share because their effect would have been anti-dilutive for the periods presented: For the Three Months Ended March 31, 2023 2022 Stock options and restricted stock units 6,987,945 4,784,076 Public and private placement warrants 7,326,654 7,326,654 Convertible Notes (if converted) 16,950,606 5,144,074

Overview - Additional Informati

Overview - Additional Information (Details) $ in Thousands	3 Months Ended
Overview - Additional Information (Details) $ in Thousands	Mar. 31, 2023 USD ($) segment	Mar. 31, 2022 USD ($)	Dec. 31, 2022 USD ($)
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Number of operating segments \| segment	1
Number of reportable segments \| segment	1
Net loss	$ (71,600)	$ (45,791)
Net cash used in operating activities	(30,478)	(42,732)
Accumulated deficit	(717,940)		$ (646,340)
Cash and cash equivalents	16,127	$ 55,361	$ 17,076
Working capital	(15,659)
Short-Term Debt	$ 11,221

Revenue Recognition - Revenue R

Revenue Recognition - Revenue Recognition Table (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Disaggregation of Revenue [Line Items]
Total revenue	$ 8,835	$ 3,298
Product revenue
Disaggregation of Revenue [Line Items]
Total revenue	8,675	3,293
Service revenue
Disaggregation of Revenue [Line Items]
Total revenue	$ 160	$ 5

Revenue Recognition - Narrative

Revenue Recognition - Narratives (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2022
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Contract assets	$ 1,914	$ (431)
Increase (decrease) in contract liabilities	(3,450)	$ 2,074
Revenue recognized in contract liabilities	3,450
Contract liabilities, current	400		$ 3,850
Contract liabilities, long-term	956		956
Contract assets, current	3,844		$ 1,859
Contract assets, long-term	$ 70
Revenue Benchmark \| Customer 1 \| Customer Concentration Risk
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Concentration risk percentage	97%	43.60%
Revenue Benchmark \| Customer 2 \| Customer Concentration Risk
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Concentration risk percentage		31.50%
Revenue Benchmark \| Customer 3 \| Customer Concentration Risk
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Concentration risk percentage		15.10%

Revenue Recognition - Informati

Revenue Recognition - Information about Contract Liabilities from Contracts with Customers (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Revenue from Contract with Customer [Abstract]
Contract assets	$ 3,914	$ 2,000
Contract liabilities	$ 1,356	$ 4,806

Cash, Cash Equivalents and Re_3

Cash, Cash Equivalents and Restricted Cash - Narrative (Details)	Jul. 29, 2022 interest_payment
Senior Secured Term Loan \| Secured Debt
Restricted Cash and Cash Equivalents Items [Line Items]
Number of immediately following interest payments required to be escrowed	4

Cash, Cash Equivalents and Re_4

Cash, Cash Equivalents and Restricted Cash (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022	Mar. 31, 2022	Dec. 31, 2021
Cash and Cash Equivalents [Abstract]
Cash and cash equivalents	$ 16,127	$ 17,076	$ 55,361
Restricted cash	2,725	2,725	0
Long-term restricted cash	11,450	11,422	1,255
Total cash, cash equivalents, and restricted cash	$ 30,302	$ 31,223	$ 56,616	$ 105,692

Inventory (Details)

Inventory (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Inventory Disclosure [Abstract]
Raw materials	$ 13,896	$ 22,899
Work-in-process	64	361
Finished goods	115	0
Total inventory, net	$ 14,075	$ 23,260

Property, Plant and Equipment_3

Property, Plant and Equipment, Net - Components of Property and Equipment (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Dec. 31, 2022
Property, Plant and Equipment [Line Items]
Property, plant, and equipment and finance lease right-of-use asset	$ 39,176	$ 39,129
Less: Accumulated depreciation	(14,559)	(11,960)
Total property, plant and equipment, net	24,617	27,169
Equipment
Property, Plant and Equipment [Line Items]
Property, plant, and equipment and finance lease right-of-use asset	$ 23,622	23,653
Equipment \| Minimum
Property, Plant and Equipment [Line Items]
Estimated Useful lives	5 years
Equipment \| Maximum
Property, Plant and Equipment [Line Items]
Estimated Useful lives	10 years
Finance lease
Property, Plant and Equipment [Line Items]
Property, plant, and equipment and finance lease right-of-use asset	$ 379	379
Estimated Useful lives	5 years
Furniture
Property, Plant and Equipment [Line Items]
Property, plant, and equipment and finance lease right-of-use asset	$ 1,892	1,868
Furniture \| Minimum
Property, Plant and Equipment [Line Items]
Estimated Useful lives	5 years
Furniture \| Maximum
Property, Plant and Equipment [Line Items]
Estimated Useful lives	10 years
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property, plant, and equipment and finance lease right-of-use asset	$ 6,629	6,303
Tooling
Property, Plant and Equipment [Line Items]
Property, plant, and equipment and finance lease right-of-use asset	$ 6,654	$ 6,926
Tooling \| Minimum
Property, Plant and Equipment [Line Items]
Estimated Useful lives	2 years
Tooling \| Maximum
Property, Plant and Equipment [Line Items]
Estimated Useful lives	3 years

Property, Plant and Equipment_4

Property, Plant and Equipment, Net - Narratives (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Property, Plant and Equipment [Abstract]
Depreciation expense related to property and equipment	$ 2,667	$ 985

Intangible Assets - Narratives

Intangible Assets - Narratives (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Finite-Lived Intangible Assets [Line Items]
Capitalized cost	$ 130
Amortization of capitalized computer software cost	9
Patents
Finite-Lived Intangible Assets [Line Items]
Gross patents value	$ 400
Patents useful lives	10 years
Patents amortization expenses	$ 10	$ 10
Software
Finite-Lived Intangible Assets [Line Items]
Patents useful lives	3 years

Notes Receivable, Net and Var_2

Notes Receivable, Net and Variable Interest Entities (“VIEs”) Consideration (Details) - Variable Interest Entity, not primary beneficiary - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Variable Interest Entity [Line Items]
Loan commitment on the consolidated balance sheet	$ 862	$ 863
Financing receivable, allowance for credit loss	$ 2	$ 2

Accrued Expenses - Schedule of

Accrued Expenses - Schedule of Accrued Expenses (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Payables and Accruals [Abstract]
Accrued payroll	$ 4,636	$ 2,706
Warranty reserve	3,972	3,836
Accrued legal and professional expenses	2,087	840
Provision for contract losses	1,936	2,561
Insurance premium payable, current	2,730	2,607
Other	4,990	2,809
Total accrued expenses	$ 20,351	$ 15,359

Accrued Expenses - Warranty Res

Accrued Expenses - Warranty Reserve Activity (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Movement in Standard Product Warranty Accrual [Roll Forward]
Warranty reserve - beginning of period	$ 3,836	$ 2,112
Additions for current period deliveries	357	673
Changes in the warranty reserve estimate	0	955
Warranty costs incurred	(221)	(500)
Warranty reserve - end of period	$ 3,972	$ 3,240

Government Grants (Details)

Government Grants (Details) - USD ($) $ in Thousands	3 Months Ended
Government Grants (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2022
Government Assistance [Line Items]
Grant expense, net	$ 0	$ 173
California Energy Commission
Government Assistance [Line Items]
Noncurrent grants receivables	$ 245		$ 263
Government Assistance, Current, Statement of Financial Position [Extensible Enumeration]	Other current assets
Production Tax Credits
Government Assistance [Line Items]
Current grants receivable	$ 798
Government Assistance, Noncurrent, Statement of Financial Position [Extensible Enumeration]	Other assets
Government assistance amount	$ 798

Related Party Transactions (Det

Related Party Transactions (Details) - USD ($)	1 Months Ended	3 Months Ended
Related Party Transactions (Details) - USD ($)	Jul. 31, 2021	Mar. 31, 2023	Mar. 31, 2022	Jan. 18, 2023	Jul. 06, 2021
Related Party Transaction [Line Items]
Payment made for debt issuance cost		$ 1,116,000	$ 0
2021 Convertible Notes \| Affiliated Entity
Related Party Transaction [Line Items]
Notes payable	$ 100,000,000
Payment made for debt issuance cost	$ 3,000,000
2021 Convertible Notes \| Convertible Notes
Related Party Transaction [Line Items]
Principal					$ 100,000,000
AFG Convertible Notes \| Convertible Notes \| Affiliated Entity
Related Party Transaction [Line Items]
Principal				$ 13,750,000
Paid-In-Kind Interest Rate				26.50%

Borrowings - Schedule of Debt (

Borrowings - Schedule of Debt (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022	Jul. 29, 2022
Borrowing Outstanding
Total borrowings	$ 236,817	$ 219,744
Current portion	11,221	5,560
Total borrowings, non-current	225,596	214,184
Carrying Value*
Total borrowings	209,785	175,831
Long-term debt, current	11,221	5,560
Long-term debt	198,564	170,271
Yorkville Convertible Promissory Note - due September 2022 \| Convertible Notes
Borrowing Outstanding
Convertible notes payable	6,000	2,000
Carrying Value*
Convertible notes payable	8,240	2,688
2021 Convertible Notes Payable - due June 2026
Carrying Value*
Convertible notes payable	85,039	82,950
2021 Convertible Notes Payable - due June 2026 \| Convertible Notes
Borrowing Outstanding
Convertible notes payable	109,167	109,167
Total borrowings	109,167	109,167
Carrying Value*
Convertible notes payable	85,039	82,950
Total borrowings	85,039	82,950
AFG Convertible Note - due June 2026
Borrowing Outstanding
Convertible notes payable		0
Carrying Value*
Convertible notes payable	26,075	0
AFG Convertible Note - due June 2026 \| Convertible Notes
Borrowing Outstanding
Convertible notes payable	13,750
Senior Secured Term Loan - due March 2026
Carrying Value*
Total borrowings	82,531	81,616
Senior Secured Term Loan - due March 2026 \| Secured Debt
Borrowing Outstanding
Total borrowings	100,000	100,000	$ 100
Carrying Value*
Total borrowings	82,531	81,616
Equipment financing facility - due April 2025
Carrying Value*
Total borrowings	7,900	8,577
Equipment financing facility - due April 2025 \| Line of Credit
Borrowing Outstanding
Total borrowings	7,900	8,577
Carrying Value*
Total borrowings	$ 7,900	$ 8,577

Borrowings - Narrative (Details

Borrowings - Narrative (Details)					1 Months Ended			3 Months Ended
Borrowings - Narrative (Details)	Mar. 17, 2023 USD ($) $ / shares	Feb. 01, 2023 USD ($) trading_day $ / shares	Jan. 18, 2023 USD ($) trading_day $ / shares	Jul. 29, 2022 USD ($) interest_payment	Mar. 31, 2023 USD ($) $ / shares shares	Feb. 28, 2023 USD ($) shares	Jan. 31, 2023 USD ($) shares	Mar. 31, 2023 USD ($) shares $ / shares	Mar. 31, 2022 USD ($)	Dec. 31, 2022 USD ($) $ / shares	Dec. 29, 2022 USD ($)	Sep. 30, 2022 USD ($)	Aug. 05, 2022 $ / shares	Jun. 28, 2022 $ / shares	Jun. 27, 2022 $ / shares	Sep. 30, 2021 USD ($)	Jul. 06, 2021 USD ($)
Debt Instrument [Line Items]
Loss on debt extinguishment								$ 1,634,000	$ 0
Carrying Value					$ 209,785,000			209,785,000		$ 175,831,000
Interest payable - related party					$ 2,417,000			$ 2,417,000		$ 0
Common stock, par value (in dollars per share) \| $ / shares			$ 0.0001		$ 0.0001			$ 0.0001		$ 0.0001			$ 0.0001	$ 0.0001	$ 0.0001
Outstanding balance					$ 236,817,000			$ 236,817,000		$ 219,744,000
Long-term debt, current					$ 2,981,000			$ 2,981,000		2,872,000
Yorkville Convertible Notes \| Convertible Notes
Debt Instrument [Line Items]
Principal											$ 2,000,000
Converted instrument, shares issued (in shares) \| shares							1,953,612
Loss on debt extinguishment							$ 338,000
Coupon Interest Rate	40%				40%			40%
Yorkville Convertible Promissory Note February 2023
Debt Instrument [Line Items]
Carrying Value		$ 5,887,000
Yorkville Convertible Promissory Note February 2023 \| Convertible Notes
Debt Instrument [Line Items]
Principal		$ 5,000,000
Converted instrument, shares issued (in shares) \| shares						3,879,706
Loss on debt extinguishment					$ 817,000	$ 479,000
Discount rate percentage		2%
Debt Issuance Costs		$ 43,000
Stated interest rate		5%
Increase in annual rate upon an event of default		15%
Conversion price per unit (in dollars per share) \| $ / shares		$ 1.4883
Lowest daily volume weighted average price		96.50%
Number of trading days \| trading_day		7
Embedded conversion feature		$ 1,323,000
Non-cash interest expense		$ 987,000
March 2023 Promissory Note
Debt Instrument [Line Items]
Carrying Value	$ 20,665,000
March 2023 Promissory Note \| Convertible Notes
Debt Instrument [Line Items]
Principal	$ 15,000,000
Converted instrument, shares issued (in shares) \| shares					5,383,174
Discount rate percentage	2%
Debt Issuance Costs	$ 64,000
Stated interest rate	5%
Increase in annual rate upon an event of default	15%
Conversion price per unit (in dollars per share) \| $ / shares	$ 1.9368
Lowest daily volume weighted average price	92.50%
Embedded conversion feature	$ 7,026,000				$ 2,849,000			$ 2,849,000
Carrying Value					8,240,000			8,240,000
Non-cash interest expense	$ 5,965,000
Outstanding balance					6,000,000			6,000,000
2021 Convertible Notes
Debt Instrument [Line Items]
Interest payable - related party					1,637,000			1,637,000		0
2021 Convertible Notes \| Convertible Notes
Debt Instrument [Line Items]
Principal																	$ 100,000,000
Embedded conversion feature					1,684,000			1,684,000		918,000
Carrying Value					85,039,000			85,039,000		82,950,000
Gain (loss) on beneficial conversion feature								(766,000)	7,695,000
Non-cash interest expense - related parties								2,961,000	2,174,000
Outstanding balance					$ 109,167,000			$ 109,167,000		$ 109,167,000
Coupon Interest Rate					40%			40%		25%
AFG Convertible Notes
Debt Instrument [Line Items]
Carrying Value			$ 16,623,000
Non-cash interest expense - related parties			$ 2,873,000
AFG Convertible Notes \| Convertible Notes
Debt Instrument [Line Items]
Conversion price per unit (in dollars per share) \| $ / shares			$ 1.67
Embedded conversion feature			$ 6,451,000		$ 16,723,000			$ 16,723,000
Carrying Value					26,075,000			$ 26,075,000
Gain (loss) on beneficial conversion feature			$ (10,272,000)
Number of shares issuable if converted (in shares) \| shares								8,233,533
Percentage of stock price			130%
Threshold trading days \| trading_day			20
Consecutive trading days \| trading_day			30
Redemption percentage			100%
Non-cash interest expense - related parties								$ 969,000
Outstanding balance					$ 13,750,000			$ 13,750,000
Coupon Interest Rate			40%		40%			40%
Senior Secured Term Loan
Debt Instrument [Line Items]
Carrying Value					$ 82,531,000			$ 82,531,000		$ 81,616,000
Senior Secured Term Loan \| SOFR \| Minimum
Debt Instrument [Line Items]
Variable rate spread				0.2616%
Senior Secured Term Loan \| NYFRB \| Minimum
Debt Instrument [Line Items]
Variable rate spread				0.50%
Senior Secured Term Loan \| Secured Debt
Debt Instrument [Line Items]
Principal				$ 100,000,000
Carrying Value					82,531,000			82,531,000		81,616,000
Non-cash interest expense - related parties								4,288,000
Outstanding balance				$ 100,000	100,000,000			100,000,000		100,000,000
Number of days prior to current maturity date				91 days
Minimum prepayment amount				$ 500,000,000
Repayment applicable treasury rate				0.50%
Number of immediately following interest payments required to be escrowed \| interest_payment				4
Interest escrowed for loan					$ 11,450,000			$ 11,450,000
Maximum borrowing capacity under agreement				$ 15,000,000
Senior Secured Term Loan \| SOFR Loans
Debt Instrument [Line Items]
Variable rate spread				8.50%
Coupon Interest Rate					13.66%			13.66%
Senior Secured Term Loan \| ABR Loans
Debt Instrument [Line Items]
Stated interest rate				7.50%
Equipment financing facility
Debt Instrument [Line Items]
Carrying Value					$ 7,900,000			$ 7,900,000		8,577,000
Non-cash interest expense - related parties								317,000	$ 219,000
Remaining borrowing capacity					13,784,000			13,784,000
Long-term line of credit					7,900,000			7,900,000		8,577,000
Long-term debt, current					2,981,000			2,981,000		2,872,000
Equipment financing facility \| Line of Credit
Debt Instrument [Line Items]
Debt Issuance Costs					271,000			271,000				$ 96,000				$ 175,000
Carrying Value					7,900,000			7,900,000		8,577,000
Outstanding balance					7,900,000			7,900,000		$ 8,577,000
Coupon Interest Rate												16.20%				14.30%
Maximum borrowing capacity					$ 25,000,000			$ 25,000,000

Borrowings - Assumptions used t

Borrowings - Assumptions used to determine the Fair Value of the Embedded Derivatives at Issuance (Details) - Yorkville Convertible Notes - Convertible Notes - $ / shares	Mar. 31, 2023	Mar. 17, 2023
Debt Instrument [Line Items]
EOSE Common Stock Price (in usd per share)	$ 2.57	$ 2.24
Debt Yield	40%	40%

Borrowings - Net Carrying Value

Borrowings - Net Carrying Value (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Mar. 17, 2023	Jan. 18, 2023	Dec. 31, 2022	Jul. 29, 2022
Debt Instrument [Line Items]
Principal	$ 236,817			$ 219,744
Total borrowings	209,785			175,831
March 2023 Promissory Note
Debt Instrument [Line Items]
Total borrowings		$ 20,665
March 2023 Promissory Note \| Convertible Notes
Debt Instrument [Line Items]
Principal	6,000
Unamortized debt discount	(545)
Unamortized debt issuance costs	(64)
Embedded conversion feature	2,849	$ 7,026
Total borrowings	8,240
2021 Convertible Notes \| Convertible Notes
Debt Instrument [Line Items]
Principal	109,167			109,167
Unamortized debt discount	(23,526)			(24,733)
Unamortized debt issuance costs	(2,286)			(2,402)
Embedded conversion feature	1,684			918
Total borrowings	85,039			82,950
AFG Convertible Notes
Debt Instrument [Line Items]
Total borrowings			$ 16,623
AFG Convertible Notes \| Convertible Notes
Debt Instrument [Line Items]
Principal	13,750
Unamortized debt discount	(3,430)
Unamortized debt issuance costs	(968)
Embedded conversion feature	16,723		$ 6,451
Total borrowings	26,075
Senior Secured Term Loan
Debt Instrument [Line Items]
Total borrowings	82,531			81,616
Senior Secured Term Loan \| Secured Debt
Debt Instrument [Line Items]
Principal	100,000			100,000	$ 100
Unamortized debt discount	(1,773)			(1,866)
Unamortized debt issuance costs	(15,696)			(16,518)
Total borrowings	$ 82,531			$ 81,616

Borrowings - Debt Assumptions (

Borrowings - Debt Assumptions (Details) - Convertible Notes		3 Months Ended	12 Months Ended
Borrowings - Debt Assumptions (Details) - Convertible Notes	Jan. 18, 2023	Mar. 31, 2023	Dec. 31, 2022
2021 Convertible Notes
Debt Instrument [Line Items]
Term		3 years 3 months	3 years 6 months
Effective debt yield		40%	25%
2021 Convertible Notes \| Dividend yield
Debt Instrument [Line Items]
Debt Instrument, measurement input		0	0
2021 Convertible Notes \| Risk-free interest rate
Debt Instrument [Line Items]
Debt Instrument, measurement input		0.037	0.041
2021 Convertible Notes \| Volatility
Debt Instrument [Line Items]
Debt Instrument, measurement input		0.700	0.800
AFG Convertible Notes
Debt Instrument [Line Items]
Term	3 years 6 months	3 years 3 months
Effective debt yield	40%	40%
AFG Convertible Notes \| Dividend yield
Debt Instrument [Line Items]
Debt Instrument, measurement input	0	0
AFG Convertible Notes \| Risk-free interest rate
Debt Instrument [Line Items]
Debt Instrument, measurement input	0.036	0.037
AFG Convertible Notes \| Volatility
Debt Instrument [Line Items]
Debt Instrument, measurement input	0.700	0.700

Borrowings - Interest Expense (

Borrowings - Interest Expense (Details) - USD ($) $ in Thousands		3 Months Ended
	Jan. 18, 2023	Mar. 31, 2023	Mar. 31, 2022
2021 Convertible Notes \| Convertible Notes
Debt Instrument [Line Items]
Contractual interest expense		$ 1,637	$ 1,544
Amortization of debt discount		1,207	543
Amortization of debt issuance costs		117	87
Total		2,961	$ 2,174
AFG Convertible Note - Related Party
Debt Instrument [Line Items]
Total	$ 2,873
AFG Convertible Note - Related Party \| Convertible Notes
Debt Instrument [Line Items]
Contractual interest expense		779
Amortization of debt discount		148
Amortization of debt issuance costs		42
Total		969
Senior Secured Term Loan \| Secured Debt
Debt Instrument [Line Items]
Contractual interest expense		3,373
Amortization of debt discount		93
Amortization of debt issuance costs		822
Total		$ 4,288

Borrowings - Equipment Financin

Borrowings - Equipment Financing Facility (Details) - Line of Credit - Equipment financing facility - USD ($) $ in Thousands	1 Months Ended		19 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Mar. 31, 2023
Debt Instrument [Line Items]
Gross Amount of Initial Draw	$ 4,216	$ 7,000	$ 11,216
Coupon Interest Rate	16.20%	14.30%
Debt Issuance Costs	$ 96	$ 175	$ 271

Warrants Liability - Related _2

Warrants Liability - Related Party (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2022
Class of Warrant or Right [Line Items]
Warrants outstanding (in shares)	7,001,654		7,001,654
Warrants liability - related party	$ 234		$ 78
Change in fair value	$ 156	$ 567
Private Placement
Class of Warrant or Right [Line Items]
Warrants outstanding (in shares)	325,000		325,000

Fair Value Measurement - Fair V

Fair Value Measurement - Fair Value of Liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Private placement warrants	$ 234	$ 78
Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Private placement warrants	0	0
Level 1 \| Embedded derivative liabilities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Embedded derivative liabilities	0	0
Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Private placement warrants	234	78
Level 2 \| Embedded derivative liabilities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Embedded derivative liabilities	0	0
Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Private placement warrants	0	0
Level 3 \| Embedded derivative liabilities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Embedded derivative liabilities	$ 21,255	$ 1,945

Fair Value Measurement - Liabil

Fair Value Measurement - Liabilities Measured at Fair Value (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2022	Dec. 31, 2021
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance at beginning of the period	$ 21,255	$ 4,664	$ 1,945	$ 12,359
Additions	14,799	0
Extinguishment from Yorkville Promissory Notes Conversions	(8,423)	0
Change in fair value included in earnings	12,934	(7,695)
Balance at end of the period	$ 21,255	$ 4,664

Fair Value Measurement - Carryi

Fair Value Measurement - Carrying Value and Fair Value (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Jan. 18, 2023	Dec. 31, 2022
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Carrying Value	$ 209,785		$ 175,831
Carrying Value	210,647		176,694
Notes receivable
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Carrying Value	862		863
AFG Convertible Notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Carrying Value		$ 16,623
Carrying Value	26,075		0
2021 Convertible Notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Carrying Value	85,039		82,950
Senior Secured Term Loan
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Carrying Value	82,531		81,616
Equipment financing facility
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Carrying Value	7,900		8,577
Yorkville Convertible Notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Carrying Value	8,240		2,688
Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	154,745		149,864
Level 3 \| Notes receivable
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	688		677
Level 3 \| AFG Convertible Notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	27,593		0
Level 3 \| 2021 Convertible Notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	46,634		62,421
Level 3 \| Senior Secured Term Loan
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	67,410		77,576
Level 3 \| Equipment financing facility
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	4,045		6,282
Level 3 \| Yorkville Convertible Notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	$ 8,375		$ 2,908

Commitments and Contingencies (

Commitments and Contingencies (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Nov. 12, 2020	Nov. 11, 2020
Other Commitments [Line Items]
Future lease payments	$ 5,897
Authorized capital stock (in shares)			125,000,000
Common stock
Other Commitments [Line Items]
Authorized capital stock (in shares)		200,000,000
Common Class A
Other Commitments [Line Items]
Authorized capital stock (in shares)			100,000,000
Common Class B
Other Commitments [Line Items]
Authorized capital stock (in shares)			25,000,000
U.S. Department of Justice
Other Commitments [Line Items]
Settlement, amount awarded to other party	1,017
Relator
Other Commitments [Line Items]
Settlement, amount awarded to other party	70
Minimum Volume Commitment
Other Commitments [Line Items]
Non-cancellable purchase commitment	$ 200

Stock-Based Compensation - Narr

Stock-Based Compensation - Narratives (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2023 USD ($)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized stock compensation expense	$ 11,320
Unrecognized stock compensation expense attributable to stock option	$ 834
Stock options \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options term	5 years
Vesting term	3 months
Stock options \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options term	10 years
Vesting term	5 years
Stock options \| Weighted Average
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting term	3 months 18 days
Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized stock compensation expense attributable to RSUs	$ 10,486
Restricted stock units \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting term	3 years
Restricted stock units \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting term	4 years
Restricted stock units \| Weighted Average
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting term	1 year 4 months 24 days

Stock-Based Compensation - Comp

Stock-Based Compensation - Compensation Expense (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock compensation expense	$ 3,363	$ 3,943
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock compensation expense	740	911
Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock compensation expense	$ 2,623	$ 3,032

Income Taxes - Narratives (Deta

Income Taxes - Narratives (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Income Tax Disclosure [Abstract]
Income tax expense (benefit)	$ 10	$ (42)

Shareholders_ Deficit - Additio

Shareholders’ Deficit - Additional Information (Details)				3 Months Ended
Shareholders’ Deficit - Additional Information (Details)	Mar. 14, 2023 USD ($) shares	Aug. 05, 2022 USD ($) $ / shares	Apr. 28, 2022 USD ($)	Mar. 31, 2023 USD ($) vote $ / shares shares	Mar. 31, 2022 USD ($) shares	Jan. 18, 2023 $ / shares	Dec. 31, 2022 $ / shares shares	Dec. 29, 2022 USD ($)	Jun. 28, 2022 $ / shares shares	Jun. 27, 2022 $ / shares shares	Dec. 31, 2021 shares	May 22, 2020 $ / shares shares
Class of Stock [Line Items]
Preferred stock, shares authorized (in shares)				1,000,000			1,000,000
Preferred stock, shares issued (in shares)				0			0
Preferred stock, shares outstanding (in shares)				0			0
Common stock, par value (in dollars per share) \| $ / shares		$ 0.0001		$ 0.0001		$ 0.0001	$ 0.0001		$ 0.0001	$ 0.0001
Common stock, shares authorized (in shares)				300,000,000			300,000,000		300,000,000	200,000,000
Number of votes for each share \| vote				1
Common stock, shares issued (in shares)				95,222,670			82,653,781
Common stock, shares outstanding (in shares)				95,222,670			82,653,781
Shares withheld from employee to cover payroll tax liability \| $				$ 345,000	$ 826,000
Common stock to be purchased through warrants (in shares)												9,075,000
Price of common stock to be purchased through warrants (in dollars per share) \| $ / shares												$ 11.50
Warrants outstanding (in shares)				7,001,654			7,001,654
Common stock
Class of Stock [Line Items]
Common stock, shares outstanding (in shares)				95,222,670	53,980,608		82,653,781				53,786,632
Exercise of warrants (in shares)				0	600
Yorkville Convertible Notes \| Convertible Notes
Class of Stock [Line Items]
Sale of stock, number of shares issued in transaction (in shares)				11,216,492
Private Placement
Class of Stock [Line Items]
Authorized value of stock to be sold \| $								$ 75,000,000
Each sale aggregate value \| $			$ 20,000,000
Share price as percentage of market price			97%
Maximum borrowing capacity under agreement \| $			$ 50,000,000
Sale of stock, number of shares issued in transaction (in shares)	683,908			683,908
Cash received on issuance of shares \| $	$ 1,250,000			$ 20,850,000
ATM
Class of Stock [Line Items]
Authorized value of stock to be sold \| $		$ 100,000,000
Commission on gross sale proceeds		3%

Shareholders_ Deficit - Anti-di

Shareholders’ Deficit - Anti-dilutive Securities (Details) - shares	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Stock options and restricted stock units
Class of Stock [Line Items]
Anti-dilutive securities excluded from calculation of diluted net loss per share (in shares)	6,987,945	4,784,076
Public and private placement warrants
Class of Stock [Line Items]
Anti-dilutive securities excluded from calculation of diluted net loss per share (in shares)	7,326,654	7,326,654
Convertible Notes (if converted)
Class of Stock [Line Items]
Anti-dilutive securities excluded from calculation of diluted net loss per share (in shares)	16,950,606	5,144,074

Subsequent Events (Details)

Subsequent Events (Details)				1 Months Ended
Subsequent Events (Details)	Apr. 12, 2023 USD ($) $ / shares shares	Apr. 10, 2023 USD ($) trading_day $ / shares	Mar. 17, 2023 USD ($) $ / shares	Apr. 30, 2023 USD ($) shares	Mar. 31, 2023 shares	May 22, 2020 $ / shares shares
Subsequent Event [Line Items]
Common stock to be purchased through warrants (in shares)						9,075,000
Exercise price of warrants (in dollars per share) \| $ / shares						$ 11.50
March 2023 Promissory Note \| Convertible Notes
Subsequent Event [Line Items]
Converted instrument, shares issued (in shares)					5,383,174
Principal \| $			$ 15,000,000
Discount rate percentage			2%
Stated interest rate			5%
Increase in annual rate upon an event of default			15%
Conversion price per unit (in dollars per share) \| $ / shares			$ 1.9368
Lowest daily volume weighted average price			92.50%
Subsequent event
Subsequent Event [Line Items]
Proceeds from issuance of common stock and warrants \| $	$ 40,000,000
Advisory fees \| $	$ 2,000,000
Subsequent event \| April 2023 Promissory Note \| Convertible Notes
Subsequent Event [Line Items]
Principal \| $		$ 15,000,000
Discount rate percentage		2%
Stated interest rate		5%
Increase in annual rate upon an event of default		15%
Conversion price per unit (in dollars per share) \| $ / shares		$ 2.8093
Lowest daily volume weighted average price		90%
Number of trading days \| trading_day		7
Common stock \| Subsequent event \| Private Warrants
Subsequent Event [Line Items]
Common stock to be purchased through warrants (in shares)	16,000,000
Exercise price of warrants (in dollars per share) \| $ / shares	$ 3.14
Warrant not exercisable term from the date of issuance	6 months
Term of warrants	5 years 6 months
Common stock \| Subsequent event \| March 2023 Promissory Note \| Convertible Notes
Subsequent Event [Line Items]
Converted instrument, shares issued (in shares)				3,258,744
Amount of debt offset \| $				$ 6,000,000
Common stock \| Subsequent event \| April 2023 Promissory Note
Subsequent Event [Line Items]
Converted instrument, shares issued (in shares)				1,349,926
Common stock \| Subsequent event \| Purchase Agreement
Subsequent Event [Line Items]
Sale of stock, number of shares issued in transaction (in shares)	16,000,000
Sale of stock, price per share (in dollars per share) \| $ / shares	$ 2.50