ESS Inc

United States

Energy Storage

Oregon-based maker of iron flow batteries (Energy Warehouse, Energy Center) for long-duration storage using earth-abundant iron, salt and water electrolyte. In financial distress: flagged going-concern doubts and nearly closed its Wilsonville plant in mid-2025 before emergency financing (including a $40M Yorkville facility) and the acquisition of VoltStorage's iron-salt IP kept it operating.