Form Energy secures $750M to scale up 100-hour grid batteries

Form Energy has taken a major step toward reshaping how the world stores renewable energy. The company announced a $750 million funding round that will go toward scaling up manufacturing of its long-duration iron-air batteries, which are designed to discharge power for up to 100 hours. This latest round comes as the company has already secured two high-profile customers: Google and Crusoe, a data center firm focused on clean energy.

The new capital brings Form Energy's total funding to over $1.2 billion, according to the company. The funds will be used to expand production capacity at its factory in Weirton, West Virginia, and to accelerate the deployment of its battery systems across multiple projects. The company's technology is based on a reversible rusting process: iron oxidizes when discharging, and the rust is converted back to iron when charging. This chemistry allows for a much lower cost per kilowatt-hour compared to lithium-ion, making it an attractive option for grid-scale storage.

## Why 100-hour batteries matter

The significance of 100-hour storage cannot be overstated. Most lithium-ion batteries provide four to six hours of backup, which is sufficient for daily peaks. However, when a region experiences several days of low wind or overcast skies, longer-duration storage becomes essential to keep the grid stable and avoid fossil-fuel peaker plants. Form Energy's batteries are designed to fill that gap, offering a cost-effective way to store energy for days at a time.

Google and Crusoe are both early adopters of this technology. Google has agreed to purchase power from a 100-hour storage project in California, while Crusoe will use Form Energy's batteries to power its data centers with round-the-clock clean energy. These partnerships signal growing confidence in long-duration storage as a viable commercial solution.

Form Energy's expansion is also a boost for U.S. manufacturing. The company has committed to creating hundreds of jobs at its West Virginia plant, which is one of the largest investments in advanced battery manufacturing in the country. As more utilities and corporations seek to decarbonize, the demand for reliable, long-duration storage is expected to surge.

With this new funding, Form Energy is positioned to become a key player in the energy transition. The company plans to begin delivering its batteries to customers in the coming years, and its success could inspire other startups to pursue similar long-duration storage technologies. For now, the focus remains on scaling production and proving that iron-air batteries can deliver on their promise of cheap, reliable, and clean energy storage.