Somerville, Massachusetts
Form Energy’s core battery technology is an iron-air system using iron, water, and air in a reversible rusting process: iron oxidizes to release electrons during discharge and converts back to iron on charge, releasing oxygen. Modules the size of a washer-dryer contain cell stacks in a water-based non-flammable electrolyte. The design delivers long-duration storage (up to 100 hours) at approximately one-tenth the cost of lithium-ion batteries, with 50–70% round-trip efficiency and sustainable scaling using abundant materials.
The flagship iron-air battery system stores electricity for up to 100 hours in modules roughly washer-dryer sized, featuring reversible rusting chemistry, water-based non-flammable electrolyte, and cell-stack module design optimized for grid-scale deployment with cost and sustainability advantages over lithium-ion alternatives.
In 2024, Form Energy raised $405 million in Series F funding and expanded its Weirton facility by 300,000 sq ft targeting 500 MW/50 GWh annual capacity by 2028. It partnered with GE Vernova for manufacturing and supply chain. Deployments include a 1.5 MW/150 MWh Great River Energy installation in Minnesota by 2025 and additional projects in New York, Georgia, and Virginia by 2026.
In 2024, Form Energy’s Series F round included investors such as T. Rowe Price, GE Vernova, TPG Rise Climate, Breakthrough Energy Ventures, Capricorn Technology Impact Funds, Coatue, Energy Impact Partners, The Engine Ventures, Temasek, GIC, and ArcelorMittal.
