Months after slashing its lofty electric vehicle goals, General Motors is intensifying its focus on energy technology to keep up with data center needs for electricity. Now, it’s announced plans to develop a cheaper, more durable battery for large-scale energy storage.

The Detroit-based automaker is working with startup Peak Energy to develop a sodium-ion battery, aiming to commercialize it by 2028. Its goal is to leapfrog the dominant battery cell tech used for energy storage packs right now — LFP (lithium-iron phosphate), which is dominated by China. Sodium batteries are cheaper to use than LFP because they don’t need an additional cooling system. They also have a 20-year usable life and are made from materials that can be sourced from within the U.S., the company said at a briefing in San Francisco on Tuesday.

“Sodium-ion actually is the better chemistry for that application. And when I say sodium-ion is better, I mean GM’s version of sodium-ion,” Kurt Kelty, GM’s battery chief and a long-time Tesla battery executive, told Forbes . He said GM is seeing great results from its prototypes, even at scorching temperatures of 55 Celsius (131 Fahrenheit).

“The competitors just can’t handle that heat, whereas our cells will. What that gets you is the ability to deploy an energy storage system without active cooling,” he said. So even though sodium cells will cost more than LFP, they’re much cheaper to use: at least 20% cheaper when installed.

GM has been scrambling to monetize battery R&D that previously focused on electric vehicles after the Trump administration killed consumer EV rebates and manufacturing programs last year. Those initiatives, pushed by President Joe Biden, were intended to reduce automotive carbon emissions and help U.S. carmakers better compete with China, the world’s EV and battery leader. Rival Ford is working with China’s CATL, the world’s largest battery maker, to produce LFP packs for the grid at U.S. plants, and GM also makes LFP batteries with South Korea’s LG Energy Solution. But when it comes to energy storage, GM sees greater longer-term potential for sodium, once it’s fully developed.

Large-scale production of sodium cells won’t happen for at least two years, the company said. Over time, sodium-ion batteries may also end up in EVs, though for now the focus is on grid packs, Kelty said. The company is also planning to produce a new lithium manganese-rich battery for large pickups and SUVs that’s due in 2028.

Even though the company downshifted its focus away from EVs, GM said it already has the largest number of EVs on the road, some 250,000, that are capable of bi-directional charging. That means they can send power back to the grid when needed. These vehicles can be used as a backup power source for homes during blackouts, but there’s also increasing interest in utilities being able to pull electricity from EV batteries when grid demands spike. GM already has a program with California’s PG&E to test that out.

“Our grid desperately needs EVs, particularly bi-directional EVs, that we can optimize and contribute to the grid,” Patti Poppe, CEO of utility PG&E, said at the GM event. “It’s the first flexible demand there’s ever been. EVs can charge at the optimal time and then provide supply back to the grid.”

The San Francisco-based utility offers a $4,500 rebate to GM’s EV owners who install smart charging equipment. This can pull power from the vehicles during high-demand periods.

Sterling Anderson, GM’s chief product officer, said that the ability to trade power back and forth between electric vehicles and utilities could expand across the U.S. and potentially offer new ways to make EVs more affordable to own.

“What if the utility effectively owns or leases back the battery?” he said. “So you buy an EV, but you pay less for the EV because you didn’t actually just buy the battery. And the utility is effectively recouping its investments in the bidirectional charging that it's getting from your car.”

That’s not happening yet. But it’s a creative way to“meaningfully drive adoption of EVs,” he said.