v3.25.4

Cover	Jan. 23, 2026
Entity Information [Line Items]
Document Type	8-K
Document Period End Date	Jan. 23, 2026
Entity Registrant Name	ESS TECH, INC.
Entity Incorporation, State or Country Code	DE
Entity File Number	001-39525
Entity Tax Identification Number	98-1550150
Entity Address, Address Line One	26440 SW Parkway Ave.
Entity Address, Address Line Two	Bldg. 83
Entity Address, City or Town	Wilsonville
Entity Address, State or Province	OR
Entity Address, Postal Zip Code	97070
City Area Code	855
Local Phone Number	423-9920
Written Communications	false
Soliciting Material	false
Pre-commencement Tender Offer	false
Pre-commencement Issuer Tender Offer	false
Entity Emerging Growth Company	false
Entity Central Index Key	0001819438
Amendment Flag	false
Common Stock 0.0001 Par Value Per Share
Entity Information [Line Items]
Title of 12(b) Security	Common Stock, $0.0001 par value per share
Trading Symbol	GWH
Security Exchange Name	NYSE
Warrants, each fifteen warrants exercisable for one share of common stock at an exercise price of $172.50
Entity Information [Line Items]
Title of 12(b) Security	Warrants, each fifteen warrants exercisable for one share of common stock at an exercise price of $172.50
Trading Symbol	GWH.W
Security Exchange Name	NYSE

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A unique 10-digit SEC-issued value to identify entities that have filed disclosures with the SEC. It is commonly abbreviated as CIK.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Commission file number. The field allows up to 17 characters. The prefix may contain 1-3 digits, the sequence number may contain 1-8 digits, the optional suffix may contain 1-4 characters, and the fields are separated with a hyphen.

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The exact name of the entity filing the report as specified in its charter, which is required by forms filed with the SEC.

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The Tax Identification Number (TIN), also known as an Employer Identification Number (EIN), is a unique 9-digit value assigned by the IRS.

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ESS Tech, Inc. 8-K