BMW has begun testing large-format, pure all-solid-state batteries (ASSB) from Solid Power in their BMW i7 test vehicle. Hailed for their ability to hold higher energy density in a more compact form, the test will be a stepping stone for BMW to integrate ASSB into a more competitive package, suitable for passenger cars of the future.
The German carmaker says that the concept battery in the i7 combines “proven Gen5 construction principles” (i.e. prismatic cells in modules) with new, innovative module concepts for integrating ASSB cells from Solid Power.
The sulfide-based electrolytes used in the Solid Power cells will be tested for their management of cell expansion during real-life use, which will further inform their strategy when it comes to controlling operating pressure and temperature conditions of the battery.
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The main benefit for using ASSB is that the batteries hold much higher energy density compared to conventional lithium-ion batteries. This increase in energy density allows for a smaller and lighter battery pack in contrast to the big and heavy batteries EVs are notorious for, which also translates to longer range.
Solid Power President and Chief Executive Officer, John Van Scoter, said, “Solid Power is 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 ASSB’s and continue to drive innovation of our sulfide electrolyte in support of that future for EVs.”
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BMW Group Vice President Battery Cell and Cell Module, Martin Schuster, added that the BMW i7 ASSB test represents the carmaker’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.”
Solid Power specialises in all-solid-state battery cell development and has been developing batteries for EVs and mobile power markets since 2011. BMW group and Solid Power, Inc. have been collaborating since 2016 and have started intensifying development for ASSB technology since 2022.
