November 16, 2025: Clarios said on November 12 it had acquired Maxwell Technologies from California-based UCAP Power for an undisclosed sum.

Maxwell, a manufacturer of supercapacitor cells and modules used in grid and onsite power applications, including datacenters, will operate as an independent, US-based business, within Clarios.

Clarios said the deal strengthens its position in high-performance, short-duration energy storage solutions. The lead and lithium battery giant said supercapacitors are perfect for storing excess energy and supporting systems during sudden spikes in peak demand.

Key benefits for Clarios include bolstering its supply chain of supercapacitors — which can deliver up to one million cycles, operate across extreme temperatures and require no maintenance or fire-risk mitigation — to support US and global original equipment customers, the firm said.

Maxwell has decades of innovation in supercapacitor systems, with more than 85 million supercapacitor cells shipped and applications spanning US energy generation, grid stabilization, automotive, transportation, and industrial automation, Clarios said.

CEO Mark Wallace said: “Maxwell’s supercapacitors are designed to provide customers with high-power energy storage solutions that emphasize reliability, safety, and long life.”

Wallace said the acquisition boosted opportunities for the battery maker to expand its presence in non-automotive sectors.

“Maxwell’s existing customer relationships in datacenters, grid, military and industrial applications will be maintained and actively developed under Clarios’ leadership.”

Maxwell was formerly owned by Tesla, which finalized its purchase of the firm in 2019. Tesla sold Maxwell to UCAP two years later.

This March, Clarios unveiled a 10-year, $6 billion plan to expand battery manufacturing and help boost US energy and critical minerals independence.

The company said its strategy, through to 2035, included increasing production of additional cutting-edge energy storage technologies.