ESS Tech, Inc.

ESS Tech, Inc. (NYSE: GWH) is a long-duration energy storage company that became publicly traded in October 2021 through a business combination with ACON S2 Acquisition Corp., a blank-check vehicle sponsored by ACON Investments, a Washington, D.C.-based private equity firm. The Oregon-based company develops iron flow battery systems designed for grid-scale and commercial energy storage applications within the clean energy sector. ESS Tech filed an 8-K with the Securities and Exchange Commission on July 11, 2025, reflecting its continuing reporting obligations as a listed public company. For comprehensive filing history, event timelines, and real-time tracking on GWH and the broader SPAC universe, sign up for full data access at SpacDesk.