By Hamza Faisal

General Motors is going all in on salt batteries. The carmaker's venture arm has led an oversubscribed $108 million Series B funding round for Peak Energy, a startup building sodium-ion energy storage systems it says can run cooler, cheaper, and safer than the lithium-ion systems that dominate the grid today.

The round was announced Tuesday, with participation from Maverick Silicon, Infinite Capital, Eclipse, Xora Innovation, and LG Technology Ventures. Peak Energy says the new capital will let it scale domestic manufacturing, fulfill more than $1 billion in existing customer orders, and launch its product into the data center market — where access to power has become the main constraint on growth.

Peak's pitch is simple: its platform uses passive cooling instead of energy-hungry active cooling systems, which it says cuts the cost of energy by up to 20% compared with conventional storage while eliminating the battery fire risks that come with lithium-ion chemistry.

A carmaker betting on the grid

GM's involvement runs deeper than a check. In June, the automaker announced a partnership with Peak Energy to jointly develop next-generation sodium-ion battery cells for the storage market, pairing GM's U.S.-based battery cell industrialization expertise with Peak's passively cooled platform.

That was followed in July by the unveiling of Peak's 4 GWh factory in Sacramento, California, which is expected to start production in the first quarter of 2027. Bloomberg reports that GM led the round specifically to help ramp up manufacturing at that California plant.

"Peak's mission from day one has been to lower the cost of energy through safer, simpler, cleaner, and more reliable technology," said Landon Mossburg, co-founder and CEO of Peak Energy. "The investment we announce today will supercharge Peak's ability to scale and deliver."

Sodium-ion's moment

Sodium-ion has moved fast from lab curiosity to serious grid contender. Peak says that in just three years it has taken the chemistry from a promising concept to a global category now widely recognized as the leading alternative to lithium-ion for grid-scale applications.

The timing is not accidental. Industry forecasts put sodium-ion demand at 257 gigawatt-hours by 2035, up from just over 1 gigawatt-hour in 2025 — a growth curve driven by utilities, independent power producers, and now data centers, all hunting for storage that does not depend on lithium supply chains.

Peak's chemistry tolerates higher operating temperatures than lithium-ion cells, which is exactly why the company is pitching the systems as an attractive solution for grids and independent power producers dealing with harsher environments.

Power-hungry AI is the real customer

The most telling detail in the announcement may be where Peak is aiming next: data centers. As AI build-outs strain power infrastructure worldwide, the startup says it is launching its product to the data center market, where access to power has become the primary constraint on growth.

It is a crowded race — Peak is one of several startups pushing grid-scale storage as AI data centers guzzle ever more electricity — but a $108 million vote of confidence from GM, plus more than $1 billion in customer commitments on the books, suggests the salt-battery moment has arrived.

By Hamza Faisal