Form Energy raises $750M to build more up to 100-hour batteries

Battery startup Form Energy said Wednesday that it has raised $750 million to expand its manufacturing capacity in West Virginia, the latest sign that the AI data center building boom is fueling investment in energy storage. The U.S. installed 9.7 gigawatt-hours of energy storage in the first three months of this year, up 32% from 2025. Most of those batteries can discharge for a few hours at most, but Form Energy’s iron-air batteries can deliver power for up to 100 hours. Long-duration storage like this is especially valuable because it can help bridge the power supply gap in renewable generation, which is expected to account for more than 90% of new U.S. generating capacity this year.

Form’s battery chemistry stores large amounts of electricity more cheaply by relying on iron instead of pricier minerals like lithium, cobalt, and nickel: inside a Form battery, iron is oxidized and reduced as it discharges and charges, turning iron into rust on discharge and reversing the process — turning rust back into iron — on charge. The approach has helped Form land major customers: Google is building a new data center in Minnesota that will be partially powered by a 30-gigawatt-hour Form battery that cost the tech company about $1 billion, Crusoe said in March it would buy 12 gigawatt-hours of batteries from Form, and utility Xcel Energy and FuturEnergy Ireland are also customers.

Some 80% of Form’s materials come from the U.S., with the balance from Europe and Asia — notably not China, which dominates both the battery supply chain and battery manufacturing globally, prompting both the Biden and Trump administrations to seek to reduce U.S. reliance on China for batteries. That domestic-focused supply chain has helped Form land customers as U.S. electricity demand rises for the first time in decades, driven largely by data centers, which are expected to quadruple their U.S. electricity use by 2035 and consume about 20% of all electricity generated in the country.

The startup currently has a backlog of commercial projects worth about 80 gigawatt-hours of energy storage, The Wall Street Journal reported, up fourfold from earlier this year. The Series G round was led by T. Rowe Price, with participation from Sequoia Capital, Coatue, GE Vernova, Breakthrough Energy Ventures, and other investors.

Why it matters

Form’s raise shows investors treating grid-scale, multi-day storage as core AI infrastructure alongside chips and data centers, and its China-free supply chain gives it a policy tailwind that lithium-based rivals largely lack.