Peak Energy Raises $108 Million as GM Ventures Leads Sodium-Ion Round

• Peak Energy closed an oversubscribed $108 million Series B led by GM Ventures to scale U.S. sodium-ion battery manufacturing.
• The company says it holds more than $1 billion in customer orders; U.S. operators added 8.3 GW of batteries in the first half of 2026.
• Its 4-GWh Sacramento factory is due to start production in the first quarter of 2027, with about 720 MWh owed to Jupiter Power that year.

Peak Energy, a U.S. developer of sodium-ion battery systems for the power grid, has closed a $108 million Series B round led by General Motors Ventures. The Burlingame, California-based company said on Oct. 21 that the round was oversubscribed.

Maverick Silicon, Infinite Capital, Eclipse, Xora Innovation and LG Technology Ventures also invested. Peak said the money will expand its U.S. battery manufacturing, help fill more than $1 billion in existing customer orders and take its system to data centers.

Peak is building that capacity in Sacramento. In July it picked the city for a 183,000-square-foot plant able to make up to 4 GWh of battery systems a year. The site carries up to $71 million in capital investment and should add 239 jobs, the company said.

U.S. operators added 8.3 GW of battery storage in the first half of 2026, taking the fleet to nearly 52 GW, U.S. Energy Information Administration data show.

The deal in numbers

• $108 million in Series B equity, led by GM Ventures with five other investors.
• $163 million raised across Peak's Series A and Series B, including $55 million in July 2024 (list.solar calculation).
• About $17.8 million of capital spending per GWh of annual capacity, based on the up-to-$71 million budget (list.solar calculation).
• 18% of the plant's yearly capacity would cover the 720 MWh due to Jupiter Power in 2027 (list.solar calculation).
• Up to 20% lower cost of energy than conventional storage systems, according to Peak.
• 26 GW of new U.S. battery storage that operators plan to bring online in 2027, according to the EIA.

GM is more than an investor. In June the carmaker and Peak agreed to develop sodium-ion cells built for grid storage. GM will design the cell in its Michigan battery labs and keep exclusive manufacturing rights, while Peak will use it in its own systems.

Peak's systems are cooled passively. Most battery storage sold today uses lithium iron phosphate (LFP) cells and needs active cooling, the company says.

Kevin McCabe, president of GM Ventures, said the technology "has significant potential in the energy storage market as a safe, cost-effective solution using abundant, domestically sourced materials."

The Sacramento line is due to start production in the first quarter of 2027. Peak's contract with Jupiter Power calls for about 720 MWh that year, with an option for a further 4 GWh from 2028 to 2030.