GM pushes bidirectional charging and sodium-ion batteries for grid support

Electric vehicle sales might be better now than the end of last year when demand fell off a cliff following the surge of purchases ahead of the end of the federal financial incentives, but it’s clear they haven’t panned out as well as many in the automotive industry had hoped.

Still, at a GM event Ars attended in San Francisco this week, the company continues to stick to its guns with an EV lineup spanning its brands. The automaker shared that it has also been working toward the adoption of bidirectional charging to help balance the grid.

With the rise of AI, data centers are placing more and more pressure on the nation’s electric infrastructure. GM wants to relieve some of that pressure with news that its GM Energy products now support vehicle-to-grid (V2G) in addition to vehicle-to-home. The grid integration requires working with utilities and includes launch partners PG&E in California and DTE Energy in Michigan. For standalone energy storage solutions, the company also announced partnering with Peak Energy on the development of sodium-ion batteries built specifically for grid energy storage.

Power from the people

A desire to reduce friction, and do so quickly, created benefits for potential EV and V2G customers. GM learned during pilot programs that it needed to make everything easier to use. It now hopes that ease-of-use translates into GM Energy system sales.

“Our mission is to deliver a customer experience like none other to that customer,” GM Energy Vice President Wade Sheffer said during an interview. “So everything has to be focused there [on bi-directional charging], that’s it. That’s our intent, and the speed at which we do it is going to be important.”

The company says it currently has over 250,000 EVs on the road that support bi-directional charging. While not every EV owner would be able to have a home energy system—good luck talking your landlord into adding a bi-directional charger to your apartment building—those that can and will could have a significant effect on the grid. By 2030, PG&E and GM are targeting 52,000 vehicles in the utility’s operating area supporting the grid with V2G.

According to GM and PG&E, that’s enough to power every home in San Francisco for half a day.

“This is really where EVs start to matter, even for those that don’t own them,” Sheffer told the audience.

Interoperability remains a challenge. The ISO 15118-20 plug-and-charge standard was updated in 2025 to support native V2G. Of course, that standard requires not just every EV and charger to implement it, but also requires utilities to play ball. It’s a large group of public and private companies that all need to work together to make this a reality. Until that happens, V2G will still be a walled garden from automaker to automaker.

For one of the partners, the goal is clear. “I’m here to say, to set the record straight, our grid desperately needs EVs, particularly bi-directional EVs that we can optimize and contribute to the grid,” PG&E CEO Patti Poppe told the assembled press. PG&E has been working on V2G pilot programs for years. Northern California is one of the largest markets for EVs in the nation. It’s also home to some of the most expensive energy costs.

The potential for EV owners to save money every month on their bill while supporting the grid during peak charging could be an intriguing proposal.

As for the specter of AI data centers and increased energy costs being passed to customers, Poppe said, “So we’re seeing every gigawatt that we can add to the grid will lower everybody’s rates 1 percent.” Poppe noted that AI could help the company work more efficiently with its current infrastructure. “We’ve initiated a new playbook of doing simultaneous engineering using AI to optimize grid placement, grid utilization, and what the right resources need to be at the right places, so that we can have the lowest cost additions,” Poppe said.

It’s yet to be seen if Poppe’s vision works out for PG&E customers.

Salt of the earth

The V2G support and deployment to GM’s lineup is important, but for steady grid support, battery storage is the future.

Recognizing this, GM also announced sodium-ion batteries that are purpose-built specifically for Energy Storage Systems (ESS) to support the electrical grid. While EV traction batteries require robust charge and discharge cycles while engineered to be as lightweight as possible, ESS batteries require a long life and to be as inexpensive as possible.

“Our strategy is simple: develop the right battery for the right application,” Kurt Kelty, GM’s vice president of battery and sustainability, said at the press briefing in San Francisco.

The sodium pyrophosphate (NFPP) batteries being developed in conjunction with Peak Energy, according to Kelty, should be 20 percent less expensive to maintain than currently available ESS batteries. Peak Energy already has sodium-ion NFPP ESS deployed. What GM announced is what it considers the next generation of the battery, and it expects to begin production of its flavor of NFPP in 2028.

GM didn’t share the manufacturing cost or the energy density target of its own batteries. Part of the 20 percent decrease in the cost of running the GM-developed sodium-ion battery pack ESS is that the batteries work within a larger operating temperature zone than LFP and NMC, between -40 °C (-40 F) and 60 °C (140 °F). GM also said that it’s targeting 10,000 to 20,000 cycles, which is more than LFP batteries.

High on their own supply

GM also announced an update to its partnership with Redwood Materials to deploy roughly 100 repurposed GM battery packs at one of the Michigan GM facilities. The deployment will generate 1.5–7.2 MWh of energy available for the location.

The ESS deployed at the location is expected to save $3 million in utilities over the lifetime of the batteries.

The two companies are already working together on recovering recycled materials from manufacturing scrap (batteries produced that don’t meet deployment standards) and end-of-life GM EV packs, and they’re working to deploy energy storage solutions.

Redwood Materials is one of the first companies to focus on EV battery recycling and deployment as a business.

GM Energy expands the business of GM beyond transportation. Working to make all of its EVs home batteries that can power a house and help balance the grid, while still GM-centric, does give potential customers the chance to enjoy one of the more intriguing parts of electric vehicle ownership while also exploring new businesses in grid management.

When asked about the future, Sheffer had an interesting take on V2G: a world where someone could pull up to a Whole Foods and plug into a bidirectional charging station even though the battery didn’t need any energy. Instead, the car would act as a battery for the store. A vehicle-to-retail model. The customer could sell electricity to Whole Foods, and when they paid for their food, they received a discount based on the amount of electricity shared with the business.

For this future, industry and regulatory standards have to be deployed that are accepted by the automotive, utility, and retail worlds. Plus, there would need to be federal and state government support. It’s not likely to happen any time soon. Instead, for now, GM and its partners are offering solutions for the grid.

When EVs started gaining in adoption, it was feared they would bring down the grid. Instead, the rolling batteries could help keep the lights on while energy-hungry AI “email summaries” its way to sucking up all the electricity.