Idemitsu Kosan will strengthen its materials business for all-solid-state batteries, which are considered important to next-generation electric vehicles (EVs), President Noriaki Sakai said in a recent interview.

The Japanese oil company is in talks with domestic and foreign automakers on a possible collaboration in all-solid-state batteries, said Sakai, who became Idemitsu president on April 1.

"We will work together if we agree on the direction to work," he said.

All-solid-state batteries have shorter charging times and enable vehicles to travel longer per charge, compared with conventional batteries.

Idemitsu plans to start supplying solid electrolytes, used to make such batteries, as early as 2027, utilizing sulfur generated during the process of making petroleum products.

"We hope to make a decision (regarding investments) on large-scale equipment to produce solid electrolytes by the end of this fiscal year," Sakai said.

The company has already been in talks with Toyota on making EVs powered by all-solid-state batteries.

Idemitsu is now considering collaborations with others as many Japanese and foreign automakers think about releasing their own such EVs, he said.

Sakai said Idemitsu will consider whether to reduce the number of its refineries in crafting the next medium-term business plan starting in fiscal 2026.

The speed of reducing oil dependence has slowed compared with only few years ago, yet the demand for petroleum products has been decreasing due to carbon reduction efforts, he said.

Sakai said at the present time he does not want to cut the number of Idemitsu's gasoline stations from 6,000 across the country.

The number of gas stations that sell oil products may gradually decrease, Sakai said. But they will remain as suppliers of hydrogen and electricity to vehicles that are "essential to regions (of the country)," he said.