BMW tests solid-state battery technology in a unit of its i7 saloon

BMW has taken a significant step forward in its commitment to electric mobility, by incorporating solid-state battery cells developed by its partner Solid Power, into a test vehicle. With this initiative, the Bavarian manufacturer aims to evaluate how these cells perform in real-world day-to-day conditions, with the goal of beginning to use this technology in its series-production models in the near future.

The collaboration between BMW and Solid Power began in 2016, but it was not until 2022 that both companies formalised a technology transfer agreement, which has now finally come to fruition. Solid Power’s cells, based on a sulphide electrolyte, have been integrated into a battery pack for the BMW i7. From this point on, the company’s engineers will be able to begin collecting data on their performance.

The design of the test battery that BMW is using is based on the construction principles of the Bavarian manufacturer’s fifth generation of batteries, with prismatic cells organised into modules. Although these are not the round cells of the future sixth generation that will be integrated into the Neue Klasse, they nonetheless represent a significant advance in the move towards solid-state battery technology. The BMW i7, presented in April 2022 as the electric flagship of the brand, undoubtedly seems to be the ideal platform for these tests.

The future of electric mobility lies with solid-state batteries

One of the main attractions of solid-state batteries is their higher energy density compared with current technologies, which should translate into increased range. However, both BMW and Solid Power say that considerably more development work will still be needed before this technology can be implemented in large-scale production.

“The BMW i7 with solid-state batteries under test reflects our open approach to innovation. Alongside partners such as Solid Power, we are expanding our knowledge of advanced battery technologies.”

Founded in 2011, Solid Power has established itself as a leader in the development of solid-state batteries. At the end of 2023, it delivered the first sample cells to BMW, thus starting the evaluation process. In addition, BMW is installing a prototype production line at its Cell Manufacturing Competence Centre in Parsdorf, near Munich, under a research and development licence granted by Solid Power.