Japan's No.2 oil refiner, Idemitsu Kosan <5019.T> plans to build a large-scale plant for lithium sulphide, a key material for all-solid-state batteries, at its Chiba refinery, near Tokyo, the company said on Thursday. Automakers and battery suppliers worldwide are racing to develop solid-state batteries, touted as crucial for longer-lasting, safer, and more affordable EVs amid slowing EV growth. The project builds on Idemitsu's partnership with Toyota Motor to commercialise next generation batte