Mitsui Kinzoku and Factorial Join Forces to Industrialize Solid-State Batteries

Mitsui Kinzoku has announced a strategic partnership with US-based Factorial Energy to scale up the manufacturing of all-solid-state batteries. The collaboration aims to combine Factorial’s proprietary solid-state cell technology with Mitsui Kinzoku’s deep expertise in advanced materials and precision components, a move that could accelerate the long-awaited commercialization of solid-state batteries for electric vehicles.

Solid-state batteries are widely regarded as a potential game-changer for the EV industry because they replace the flammable liquid electrolyte found in conventional lithium-ion cells with a solid material. This switch promises higher energy density, faster charging times, and improved safety. However, producing them at scale and at competitive cost has proven difficult, which is why partnerships between innovative battery developers and established manufacturing specialists are becoming increasingly common.

Under the agreement, Mitsui Kinzoku will contribute its know-how in materials processing and component manufacturing—areas where the Japanese company has decades of experience serving the electronics and automotive sectors. Factorial, meanwhile, brings its solid-state platform, which has already attracted attention from major automakers through separate development deals. By working together, the two firms hope to overcome the engineering hurdles that have kept solid-state batteries largely confined to laboratories and pilot lines.

The news comes amid a global race to improve battery performance and reduce reliance on critical raw materials. Automakers and suppliers are investing heavily in next-generation battery technologies, and solid-state cells are often cited as the next major milestone after today’s lithium-ion improvements. While the timeline for mass production remains uncertain, collaborations like this one signal that the industry is moving from pure research toward practical manufacturing solutions.

For Mitsui Kinzoku, the partnership represents a chance to expand its role in the electric vehicle supply chain beyond traditional components. For Factorial, it provides access to manufacturing scale-up capabilities that are essential for bringing its technology to market. Neither company has disclosed financial terms or a specific production timeline, but the alliance underscores the growing momentum behind solid-state battery development.