San Diego-based Wildcat Discovery Technologies says it has inked a multiyear joint development agreement with Asahi Kasei Corp. to develop advanced rechargeable battery technologies. Terms of the deal were not disclosed.

The agreement is significant because it calls for an in-depth, multiyear project, said Wildcat Discovery Technologies CEO Mark Gresser. Previously Wildcat’s collaborations were for a year or part of a year.

Wildcat seeks to rapidly develop and optimize new materials for battery applications. The Mira Mesa company, which has 32 employees, has technology to test new materials on a large scale. Two years ago it was able to test 500 materials per week; today it has the capacity to handle 5,000 per week, Gresser said.

Asahi Kasei is one of Japan’s leading chemical manufacturers and a leading developer and global supplier of separator membranes for lithium-ion batteries.

Wildcat’s investors include Virgin Green Fund, CMEA Ventures, 5AM Ventures and Lawrence Berkeley National Laboratory.