Toyota's 40-Year Solid-State Battery Could Change Everything We Know About EVs

The automaker claims the next-gen EV batteries will outlast the vehicle itself and get reinstalled in new ones.

Lexus LS Coupe Concept

Photo by: Lexus

Suvrat Kothari

By: Suvrat Kothari

Nov 7, 2025 at 3:00pm ET

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Toyota's next-generation electric vehicle batteries could vastly improve the driving range and charging speeds compared to today's packs.
The company is reportedly working on cells that can last four decades and be reused multiple times during that period.
The aging will happen with minimal energy degradation, the company claims.

Writing about solid-state batteries feels like waiting for a train that’s always five minutes away, but it never actually arrives. Automakers have been developing these ‘holy grail’ batteries for years, but we’re yet to see a real-world mass-market application.

The bold claims, however, continue to land much faster than the tech itself. But what their makers intend to do with this technology can speak volumes as well. At the recently concluded Japan Mobility Show, Toyota said that its solid-state batteries are designed to last 40 years.

If that’s true, that would be about 2.7 times the average age of a passenger vehicle in the U.S. as of 2025, which now stands at 14.5 years according to the Bureau of Transportation Statistics.

Keiji Kaita, the president of Toyota’s Carbon Neutral Advanced Engineering Development Centre, explained these goals to the Australian news outlet Car Expert.

"The existing lithium battery we are making now, by the typical usage, our target is maybe 10 years, 90% capacity,” Kaita said. “This [SSB] is maybe 40 years, 90% capacity—this is the potential we are targeting.” If what Toyota says is true, it could radically change how batteries are made and used in vehicles.

Toyota Battery Technology Roadmap

Photo by: Toyota

Kaita told the outlet that while the cost of these batteries could be greater upfront, over time, they would make up that difference with longevity. “So initially, indeed, the price is much higher—but gradually that will get close to others—but we’d like to use the long-life, super long-life [lifespan] features,” he said.

Automakers and battery experts have long said that solid-state batteries can deliver longer range, reduce the pack weight significantly and improve the cells’ safety profile, meaning the fire risk could be lower. Theoretically, these batteries will also be faster-charging and more durable.

Battery makers also say these new packs will last far longer, with Toyota claiming its 40-year all-solid-state battery will retain 90% of its original capacity by the end of that timeframe. Currently, automakers typically offer eight-year warranties on their high-voltage packs. Tesla has previously said that on average, its lithium-ion batteries can last 200,000 miles with about 90% capacity retention.

Lexus LF-Z Electrified concept

However, battery companies all have different estimates on how long they can last, although there seems to be some sort of consensus that the solid-state batteries can handle a far higher number of charge-discharge cycles.

Colorado-based Solid Power, which is working with BMW to develop solid-state tech, says its experimental solid-state batteries can last more than 1,000 charging cycles. A Harvard University study said it had developed a battery that retained 80% of its original capacity after 6,000 cycles. Samsung SDI didn’t provide an estimate based on charge and discharge cycles, but said its solid-state batteries will be designed to last 20 years.

The potential benefits could be fewer replacements, lower costs over a vehicle’s life, and a significant reduction in environmental impact from battery production—fewer batteries mean less labor-intensive mining and also reduced wastage in the longer term.

Toyota Corolla Concept (2026)

Photo by: Toyota

To bring its solid-state dreams to life, the company has struck deals with electrolyte supplier Idemitsu Kosan and cathode-material supplier Sumitomo Metal Mining. The latter has said it will prioritize supplying Toyota first, followed by other customers.

We’ve also heard conflicting accounts of where Toyota will first deploy the solid-state batteries. Gill Pratt, Toyota’s chief scientist and head of the Toyota Research Institute, previously said that the first application could be on a Toyota hybrid. But at the 2025 Japan Mobility show, the company indicated a "high-power, compact and long range" application. So the production version of this Lexus Electrified Sport Concept, a potential successor to the LFA, could be a logical application.

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Or, who knows, both a hybrid and a sports car could get them around the same 2027-2028 timeframe. Either way, Toyota's been promising solid-state batteries for a long time now—but if it can finally deliver on these big claims, the EV market could be in for a major reset.

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