Peak Energy Raises $108 Million to Scale US Sodium-Ion Battery Manufacturing

Peak Energy has closed an oversubscribed $108 million Series B funding round led by General Motors Ventures, the companies announced October 21, as the Burlingame, California-based startup moves to scale up US manufacturing of sodium-ion batteries for grid storage and expand into the data center market. Maverick Silicon, Infinite Capital, Eclipse, Xora Innovation and LG Technology Ventures also took part in the round.

A lithium-free bet on grid batteries

Peak Energy builds stationary storage systems around sodium-ion cells rather than the lithium-ion chemistry used in most of today’s grid batteries. Sodium is far more abundant than lithium or cobalt and is not subject to the same supply-chain bottlenecks, a distinction that has drawn growing interest from utilities and battery developers as global demand for storage accelerates. The company says its systems use a passive-cooling design that it claims can cut energy costs by up to 20% compared with conventional lithium-ion storage, though that figure is Peak’s own estimate rather than an independently verified benchmark.

Scaling a Sacramento plant and chasing data center demand

The new capital is earmarked for three things: ramping up US manufacturing, fulfilling more than $1 billion in existing customer orders, and pushing into the data center storage market, where AI-driven electricity demand has made backup and grid-balancing capacity increasingly valuable. Peak’s flagship factory in Sacramento, California, is a 4 gigawatt-hour facility scheduled to begin production in the first quarter of 2027. The company already has commercial agreements in place with Jupiter Power, RWE and Energy Vault.

GM’s second bet on sodium-ion

General Motors Ventures’ lead investment builds on a June 2026 partnership in which GM and Peak Energy agreed to jointly develop next-generation sodium-ion cells for stationary storage. For GM, the deal gives it a stake in a storage chemistry that sidesteps some of the critical-mineral exposure tied to electric-vehicle-grade lithium-ion batteries; for Peak, it brings an automotive-scale manufacturing partner as it tries to move from pilot lines to volume production.

How sodium-ion stacks up against lithium-ion

Sodium-ion cells generally store less energy by weight and volume than lithium-ion, a tradeoff that has kept the chemistry out of electric vehicles, where space and weight are at a premium. For stationary storage bolted to a wall or sitting in a shipping container, that difference matters far less, while sodium-ion’s reliance on abundant, non-strategic materials — iron, manganese and sodium itself rather than lithium, nickel or cobalt — can make it cheaper and less exposed to the kind of mineral-supply disruptions that have periodically unsettled battery markets. That tradeoff is why a cluster of startups, Peak Energy among them, has targeted grid and industrial storage first rather than trying to compete head-on with lithium-ion in cars.

Part of a broader sodium-ion push

Peak Energy’s raise lands as sodium-ion technology gains traction elsewhere in the storage market: German startup Revolta recently won an EU grant for a sodium-ion home battery that skips rooftop solar panels entirely, and Chinese grid operators in Zhejiang have opened a dedicated spot market for grid-side batteries as storage deployment accelerates. In the US, data from Lawrence Berkeley National Laboratory shows the share of new residential solar systems paired with a battery has already climbed to 37%, underscoring how quickly storage, in whichever chemistry, is becoming a standard part of the grid rather than a niche add-on.

Sources

• EconoTimes, “Peak Energy Raises $108 Million for U.S. Sodium-Ion Expansion,” October 21, 2026 — funding amount, use of proceeds and investor list.
• GM Authority, “GM Leads $108M Series B Funding Round for Peak Energy Battery Startup,” October 2026 — GM Ventures’ role and the June 2026 GM-Peak partnership.

Illustrative image. Photo: Kecko from Eastern Switzerland, CC BY 2.0, via Wikimedia Commons — source