ESS Tech (GWH) 10-Q 2022 Q3 Quarterly report

EXHIBIT 32.2

CERTIFICATION PURSUANT TO

18 U.S.C. SECTION 1350

AS ADOPTED PURSUANT TO

SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002

Inconnection with the Quarterly Report of ESS Tech, Inc.(the“Company”)onForm10-Q forthe quarter ended September 30, 2022,asfiledwiththeSecuritiesandExchange Commissionon thedatehereof(the “Report”), I,Amir Moftakhar,ChiefFinancialOfficerof the Company, certify, pursuantto 18 U.S.C. Section1350, as adoptedpursuantto Section906 of theSarbanes-OxleyAct of 2002, that,to thebestof my knowledge:

1.the Report fully complies with the requirements of Section 13(a) or 15(d) of the Securities Exchange Act of 1934; and

2.theinformationcontainedintheReportfairlypresents,inallmaterialrespects,thefinancialconditionand resultsof operationsof the Company.

November 3, 2022	By:	/s/ Amir Moftakhar
		Name: Amir Moftakhar
		Title: Chief Financial Officer
		(Principal Financial Officer)