Toyota partner Idemitsu Kosan builds pilot plant for solid electrolytes

It has been known since 2023 that Toyota aims to begin commercialising solid-state batteries between 2027 and 2028, which the car manufacturer believes will enable ranges of initially 1,200 kilometres and up to 1,500 kilometres at peak performance. Toyota has recently intensified these efforts and is cooperating with Sumitomo Metal Mining to develop suitable cathode material.

However, Sumitomo is not the only partner: Japanese mineral oil and chemical company Idemitsu Kosan is now collaborating with Toyota on a large-scale pilot plant for the production of solid electrolytes for solid-state batteries. From 2027, the plant is expected to supply material for the industrialisation of solid-state batteries, which Toyota then intends to use in its electric vehicles.

Two small-scale demonstration plants from Idemitsu had previously proven successful. In addition, Idemitsu announced around a year ago that it would build a plant for the production of lithium sulphide as an intermediate raw material for solid-state battery electrolytes, which also contributes to the collaboration with Toyota. This plant is also scheduled for completion in 2027.

The new pilot plant is being built at Idemitsu’s site in Ichihara, Chiba Prefecture, and is expected to achieve a production capacity of several hundred tonnes of solid electrolyte per year. The project is part of the Japanese Green Innovation Fund and is supported by the government funding organisation NEDO. By expanding its production capacity, Idemitsu is pursuing its goal of establishing an integrated value chain from raw materials to battery materials.

In solid-state batteries, solid electrolytes replace the liquid electrolytes used in conventional lithium-ion cells with a solid material. This makes all-solid-state batteries more thermally stable and safer, and they also promise higher energy densities and shorter charging times. This also enables significantly longer ranges. However, there are still very few solid-state batteries on the market. One important solid-state battery developer is QuantumScape, in which VW acquired a stake back in 2012 and whose technology the German automobile manufacturer wants to license in the future so that its battery subsidiary PowerCo can then build the solid-state cells itself. Factorial, like QuantumScape also based in the USA, has in turn gained Mercedes-Benz and Stellantis as strategic investors.

electrek.co, idemitsu.com (PDF in Japanese)