Toyota has been working on a solid-state pilot program with Japanese refining oil giant Idemitsu Kosan since 2023 — but we’re way past that now. The companies have decided to move ahead with a new factory to produce solid electrolyte for all-solid-state EV batteries.

Toyota and Idemitsu Kosan first began collaborating on the development of mass production technology for solid electrolytes back in October of 2023, focusing on sulfide solid electrolytes, which have long been considered a promising material to choice to achieve scale production of solid-state EV batteries. Sulfide solid electrolytes are characterized by softness and adhesiveness to other materials, two features that make them particularly suitable for mass production.

As for why an oil company is getting involved in EVs, that’s because companies like Idemitsu Kosan sit on massive sulfur streams produced during fuel desulfurization, and converting that low-value sulfur into a high-margin material like lithium sulfide could be a once-in-a-generation win for the oil refining business the likes of which hasn’t been seen since Henry Ford decided the Model T would run on gasoline (once a simple byproduct itself, gasoline became the cornerstone of the 20th century’s global transportation system).

For their part, Idemitsu Kosan executives absolutely get it:

They are byproducts of improving petroleum products. Idemitsu discovered the usefulness of sulfur components in the mid-1990s, and through our research and technological capabilities cultivated over many years, we have succeeded in creating a solid electrolyte. This solid electrolyte is about to open up a new future for mobility.

SHUNICHI KITO
CEO, Idemitsu Kosan Co., Ltd.

The original product roadmap published by the two companies in late 2023 aimed for the successful commercialization of their all-solid-state batteries for a battery-electric Toyota that could offer 1,000 km (~620 miles) of range and 10-80% charging in about 10 minutes in 2027-28, and this most recent announcement seems to indicate they are on schedule.

In addition to Idemitsu Kosan, Toyota is also partnering with Sumitomo Metal Mining, a Japanese mining group, to secure high-performance cathode materials for the new solid-state battery plant, which is expected to be capable of producing “several hundred metric tons” of solid electrolyte material once it’s fully online.

Electrek’s Take

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Toyota solid-state battery plant; via Carscoops.

Take it from your uncle Jojo: Toyota doesn’t lose the long games. When it decides its solid-state batteries are ready, expect the company that spent decades pumping the brakes on BEVs to suddenly floor it — in the market, and in Washington alike, fighting for tough battery legislation on the grounds of consumer protections, fire safety, and recyclability.

Like the scorpion and the mixed metaphor, this is Toyota doing what it does: putting all its pieces in position, sacrificing pawns here and there, until it sets you up for the final checkmate.

SOURCES: Idemitsu Kosan and Toyota; via CarScoops, Reuters.

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