Large-format, pure all-solid-state battery (ASSB) cells from Solid Power jointly developed with BMW have been integrated into an i7 test vehicle, which is currently undergoing trials in the Munich area. The concept battery integrated in the sedan combines Gen5 construction principles (prismatic cells in modules) with new module concepts for integrating ASSB cells.
ASSB technology promises higher energy density in a more compact storage system compared to current lithium-ion batteries.
The test program will focus on key technical challenges, including how to manage cell expansion, regulate operating pressure and optimize temperature conditions within the new battery system. As part of its ongoing test program, BMW is fully integrating Solid Power’s sulfide-based all-solid-state battery cells into a complete battery pack. Over the coming months, this integration is expected to yield valuable insights that will help advance the development of next-generation battery technology.
Further development is required to implement ASSB technology in a competitive overall storage system.
Martin Schuster, VP of battery cell and cell module at BMW Group, said, “Our BMW i7 ASSB test vehicle is a perfect example of the BMW Group’s technology-open mindset. We are continuously advancing the development of new battery cell technologies and are constantly expanding our know-how with valuable partners such as Solid Power.”

BMW plans to set-up a solid-state cell prototype line at its Cell Manufacturing Competence Center in Parsdorf, using a research and development license and drawing on Solid Power’s experience.
“We are extremely proud that our partnership with BMW has resulted in the first demonstration of truly all-solid-state battery cells in a vehicle. We believe in the promise of ASSBs and continue to drive innovation of our sulfide electrolyte in support of that future for EVs,” said John Van Scoter, president and CEO of Solid Power.
BMW and Solid Power have worked together for many years, and since 2022, have expanded their collaboration, working closely to accelerate the development of ASSB technology.
In other news,
BMW has revealed its rolling testbed vehicle for drivetrain and dynamics management technology developed for the Neue Klasse – the next generation of BMW vehicles. Click here to read the full story
In the March 2025 edition of ATTI, BMW’s outgoing development director, Frank Weber discusses the program behind the Neue Klasse in more detail.