BMW i7 hits the road with all-solid-state battery from Solid Power

BMW and Solid Power begin real-world testing of solid-state batteries in the i7, aiming for higher energy density and safety in future EVs.

BMW is taking solid-state battery (ASSB) technology out of the lab and onto real-world roads. In the Munich area, testing has begun on a BMW i7 equipped with a prototype battery developed in collaboration with U.S.-based Solid Power. This marks the first demonstration of truly all-solid-state battery cells in a vehicle—a milestone that could reshape the future of electric mobility.

Unlike conventional lithium-ion batteries, ASSB cells use sulfide-based electrolytes and contain no liquid components. This dramatically lowers fire risks and improves thermal stability. In terms of performance, the cells already reach an energy density of 330 Wh/kg, with potential to scale to 390 Wh/kg. That level of density offers the promise of longer range without adding extra weight—a major hurdle for EV design.

The test battery inside the BMW i7 combines Gen5 modular architecture—built around prismatic cells—with new integration concepts specific to ASSB. Engineers are closely observing cell expansion behavior, pressure control, and temperature regulation. The findings from these trials will help define the next phase of battery development.

BMW and Solid Power have been partners since 2016. Their collaboration deepened in late 2022, when BMW acquired a research license and announced plans to run a prototype solid-state cell production line at its CMCC facility in Parsdorf, near Munich. This step is critical for scaling R&D and reducing reliance on external suppliers.

Martin Schuster, BMW’s Vice President for Battery Cell and Module Development, called the i7 ASSB project a "perfect example of BMW's technology-open mindset." He emphasized the importance of building in-house knowledge while working alongside innovative partners.

From Solid Power’s side, CEO John Van Scoter described the test vehicle as the first real-world application of fully solid-state battery cells. It’s a bold claim, underscoring the significance of the milestone.

Challenges remain—from production scaling to cost-efficiency—but the fact that the i7 ASSB is already on public roads suggests that the technology is maturing. If development stays on track, solid-state batteries may soon power BMW’s next-gen electric lineup, including the highly anticipated Neue Klasse platform set to debut in 2025.

Source: bmwgroup.com