Form Energy Reveals Chemistry of its Long Duration Iron-air Battery

US technology firm Form Energy has announced the battery chemistry of its first commercial product and a $200 million Series D financing round led by ArcelorMittal’s XCarb™ innovation fund. The four-year-old startup claims that through the use of iron, one of the most common elements on Earth, it has built an inexpensive battery that can discharge power for days on end.

The company is currently working on developing a new class of cost-effective, multi-day energy storage systems to fight climate change.

Solar and wind resources are the lowest marginal cost sources of electricity in most of the world. The electric grid now faces a challenge: how to manage the multi-day variability of renewable energy, even in periods of multi-day weather events, without sacrificing energy reliability or affordability.

Form Energy’s first commercial product is a rechargeable iron-air battery capable of delivering electricity for 100 hours at system costs competitive with conventional power plants and at less than 1/10th the cost of lithium-ion. Made from iron, one of the safest, cheapest, and most abundant minerals on Earth, this front-of-the-meter battery can be used continuously over a multi-day period and will enable a reliable, secure, and fully renewable electric grid year-round, said the company in a press statement.

How Does it Work? 

Form Energy battery is composed of cells filled with thousands of small iron pellets that rust when exposed to air. When oxygen is removed, the rust reverts to iron. By controlling the process, the battery is charged and discharged. The firm’s plan is to mount small cells into larger modules, then assemble modules into batteries that can be scaled to power electric grids. The firm’s first battery, a 300Mwh, full-scale pilot project, using 500 modules, is under construction at the Great River Energy power plant in Minnesota in 2023. Form Energy intends to source the iron domestically and manufacture the battery systems close to the final site. The Minnesota project is right near the American Iron Range.

Mateo Jaramillo, CEO and Co-founder of Form Energy, said, “We conducted a broad review of available technologies and have reinvented the iron-air battery to optimize it for multi-day energy storage for the electric grid. With this technology, we are tackling the biggest barrier to deep decarbonization: making renewable energy available when and where it’s needed, even during multiple days of extreme weather or grid outages.”

The Arcelor Mittal Connection

Form Energy and ArcelorMittal are working jointly on the development of iron materials which ArcelorMittal would non-exclusively supply for Form’s battery systems. Greg Ludkovsky, Global Head of Research and Development at ArcelorMittal, said, “Form Energy is at the leading edge of developments in the long-duration, grid-scale battery storage space. The multi-day energy storage technology they have developed holds exciting potential to overcome the issue of intermittent supply of renewable energy. They are exactly the kind of ambitious and innovative company we are seeking to invest in through our XCarb™ innovation fund.”

Jaramillo added, “This is an extremely exciting time at Form Energy and we are pleased to welcome ArcelorMittal as a business partner and investor. ArcelorMittal is a world-leading steel and mining company and this investment demonstrates their commitment to innovation and deep decarbonization. We appreciate their confidence in our team and in our technology as we work to reshape the global electric system to enable a clean energy future.”