Form Energy

Energy Storage · Climate Tech · Grid Infrastructure

Funding

Form Energy raises $750M Series G to scale iron-air grid batteries

Its surging order backlog exposes a mismatch: the grid pays for power in kilowatts, while Form's cost edge lives in kilowatt-hours.

• Form Energy closed a $750 million Series G led by T. Rowe Price, joined by Sequoia Capital, Janus Henderson, and Franklin Templeton, lifting total funding past $2 billion.
• Form Energy makes iron-air batteries that store electricity through a reaction between iron and oxygen, essentially controlled rusting, discharging for up to 100 hours versus lithium-ion's typical 2-8 hours.
• The new capital expands manufacturing capacity at Form's West Virginia plant and accelerates commercial deployment of its iron-air systems.
• Form's commercial backlog quadrupled this year, from roughly 20 gigawatt-hours to 80 gigawatt-hours, with projects for Xcel Energy, Google, Crusoe, and FuturEnergy Ireland.
• The technology targets system costs below $20 per kWh for 100-hour storage, a roughly 90% CapEx cut versus lithium-ion, despite a lower 40-50% round-trip efficiency compared to lithium's 85-92%.
• Founder Mateo Jaramillo calls the product an "e-peaker," likening it to gas turbines utilities fire up only a few days a year, though critics argue that framing invites comparison on the very power metric where iron-air currently trails.
• The real test isn't the chemistry but the metric: utilities buy power in kilowatts, and Form's 80 GWh backlog converts to only about 800 megawatts of dispatchable capacity, roughly one mid-size gas plant.