Catalyzing a Cleaner Future. Every Day. First Quarter 2026 Financial Results Conference Call Investor Presentation NYSE: GWH May 7, 2026 Disclaimers No part of this presentation may be reproduced, photocopied, redistributed or passed on, directly or indirectly, to any other person, or published, in whole or in part, for any purpose without the consent of ESS Tech, Inc. ("ESS"). This presentation contains certain "forward-looking statements" within the meaning of the United States Private Securities Litigati ...