ESS Tech, Inc. (NYSE:GWH) (the "Company"), a leading provider of safer, non-lithium energy storage solutions, today announced that it has entered into definitive agreements in a registered direct offering with institutional investors for the purchase and sale of 6.4 million shares of common stock at a price of $0.50 per share of common stock. In addition, in a concurrent private placement, the Company will issue to investors warrants to purchase up to 12,800,000 shares of common stock. The warrants have an exercise price of $0.50 per share and will become exercisable immediately following the date of stockholder approval and expire on the fifth anniversary of the issuance date of the warrant. The registered direct offering of common stock and the concurrent private placement of warrants are collectively referred to as the offering herein.

The offering consists of the sale of 6.4 million shares of common stock. The public offering price per share and accompanying warrant is $0.50.

Aggregate gross proceeds to the Company are expected to be approximately $3.2 million, before deducting placement agent fees and other offering expenses payable by the Company. The transaction is expected to close on or about August 21, 2026, subject to the satisfaction of customary closing conditions. The Company expects to use the net proceeds from the offering, together with its existing cash, for general corporate purposes and working capital.

Roth Capital Partners is acting as exclusive placement agent for the offering. Wilson Sonsini Goodrich & Rosati, P.C. is acting as counsel to the Company. Pryor Cashman LLP is acting as counsel to Roth Capital Partners, LLC.