Sodium-ion storage maker Peak Energy raises $108 million in GM-led round

Peak Energy said its oversubscribed Series B was led by GM Ventures, with participation from Maverick Silicon, Infinite Capital, Eclipse, Xora Innovation and LG Technology Ventures. The company did not disclose its valuation or the size of GM Ventures’ contribution.

Peak Energy said the funding will help it scale domestic manufacturing, fulfill more than $1 billion in existing customer orders and launch its passively cooled sodium-ion systems in the data center market. The round follows a $55 million Series A in 2024.

“The investment we announce today will supercharge Peak’s ability to scale and deliver as the world increasingly turns to passively cooled sodium-ion storage to solve our energy needs,” said Landon Mossburg, Peak’s co-founder and chief executive officer.

Order book

Peak Energy has not broken down the $1 billion figure. Its largest disclosed deal is a multi-year phased agreement with Jupiter Power for up to 4.75 GWh between 2027 and 2030, starting with about 720 MWh in 2027 and including an option for a further 4 GWh from 2028 to 2030.

In February, Energy Vault signed what it described as a definitive supply agreement for 1.5 GWh of Peak Energy systems, alongside a joint development agreement for storage serving AI data centers. Neither company has named an end customer or site. Peak Energy has also agreed to pilot a sodium-ion system with RWE’s US business in the Midcontinent Independent System Operator (MISO) market, though no capacity was disclosed.

When Peak announced its factory in July, it said it had more than 6 GWh of customer commitments.

Cell supply

Peak Energy said its 183,000-square-foot Sacramento plant is designed for up to 4 GWh of annual output, with production scheduled to begin in the first quarter of 2027. The company has put the capital investment at about $71 million.

The company currently sources cells from manufacturers in China, built to its specifications, and assembles them into containers at its facility in Burlingame, California. In June, it partnered with GM to co-develop next-generation sodium-ion cells with the carmaker’s Michigan battery labs.

“GM Ventures is investing to help Peak Energy continue to scale this innovative technology because we believe it has significant potential in the energy storage market as a safe, cost-effective solution using abundant, domestically sourced materials,” said Kevin McCabe, president of GM Ventures.

Peak Energy said its system, which eliminates active cooling, can cut the cost of energy by up to 20% compared with conventional storage and requires zero planned maintenance. The claims have not been independently verified.

The company unveiled its first grid-scale system in July 2025 at the Solar Technology Acceleration Center (SolarTAC) test facility in Colorado, and began operating the 3.5 MWh installation that September with nine utilities and independent power producers. It had earlier set up a sodium-ion cell engineering center in Colorado.