America's first commercial factory dedicated to sodium-ion grid storage batteries is going up in Sacramento. Sodium-ion is a battery chemistry that uses sodium to carry an electrical charge instead of lithium, a design difference that matters because sodium is more widely available than lithium and, by Peak Energy's account, cheaper to work with at scale. Peak Energy, based in Burlingame, California, announced the city selection on July 8, 2026, attaching up to $71 million in investment and 239 local jobs to the project.
What this factory will make
Grid-scale storage is a battery system large enough to serve an entire electrical grid rather than a single building. When generation outpaces demand, these batteries absorb the surplus. When demand climbs past what generators can supply at a given moment, the batteries discharge back into the grid. The Sacramento plant is designed to produce up to 4 gigawatt-hours of that capacity per year. A gigawatt-hour is a unit of stored energy, the scale used when sizing projects built to affect regional power supply.
What Peak Energy has put on record
The $71 million investment figure is a ceiling, not a guarantee. Peak Energy described it as "up to" that amount. The 239 jobs figure is what the company projects for local employment. The announcement does not specify a construction start date or when production is expected to begin. Those are the numbers the company has offered publicly; the rest is projection.
The sodium-ion argument
Peak Energy's commercial case rests on sodium-ion chemistry's cost profile relative to lithium-ion. The company describes itself as a U.S. leader in low-cost, giga-scale grid storage. Sodium is more abundant than lithium, which is sourced from a narrow set of global supply chains. A domestic factory producing this chemistry gives U.S. grid operators a home-market alternative to that supply chain. The annual output target is 4 GWh.