BMW tests advanced solid-state batteries in extreme conditions while rivals like Toyota and Mercedes-Benz announce aggressive timelines, reshaping the EV battery race.
BMW is conducting rigorous extreme-climate testing of all-solid-state battery (ASSB) prototypes developed with U.S. partner Solid Power, achieving 30% higher energy density than current lithium-ion cells. As the German automaker targets 2028-2030 for mass production, competitors are advancing faster timelines – Toyota plans 745-mile ASSB EVs by 2027 while CATL’s semi-solid-state batteries enter production this year.
BMW’s Extreme Testing Reveals Performance Gaps
According to data obtained by Auto Motor und Sport (July 1, 2024), BMW’s modified i7 prototypes equipped with Solid Power’s 20 Ah all-solid-state cells demonstrated 30% faster charge decay in temperatures below -20°C compared to Nio’s semi-solid-state packs. This comes as Solid Power began pilot production of automotive-grade ASSBs in June, with BMW confirming the cells meet 90% of performance targets.
“The cold weather performance gap shows why we’re testing across Death Valley and the Arctic Circle,” said BMW battery chief Peter Lamp during a July 3 tech briefing. “Our partnership with Solid Power allows iterative improvements – we’ve already doubled cycle life since 2023 prototypes.”
The 2025-2028 Battery Wars Heat Up
While BMW maintains its conservative 2028-2030 timeline, competitors are making bold moves:
- Toyota committed $13.6 billion through 2030 to launch ASSB EVs with 745-mile range by 2027-2028
- Mercedes-Benz partnered with Taiwan’s ProLogium on 15-minute fast-charging ASSBs for 2025 prototypes
- CATL began production of semi-solid-state batteries claiming 1,000 km range at half the cost of BMW’s current i7 packs
“The industry is splitting between evolutionary and revolutionary paths,” noted BloombergNEF analyst James Frith. “BMW’s dual strategy – pushing ASSBs while expanding LFP production – hedges bets but risks falling behind in the premium segment.”
Material Science Breakthroughs Needed
The race hinges on solving fundamental challenges. Solid Power’s sulfide-based electrolyte requires precise pressure control, while ProLogium’s oxide-based approach faces thickness limitations. BMW’s tests revealed its cobalt-free cathode formulation loses 8% more capacity after 500 cycles than conventional batteries in tropical conditions.
As automakers navigate these tradeoffs, the coming 18 months will prove decisive. With Toyota’s 2027 target now serving as the industry benchmark, BMW may need to accelerate its roadmap to maintain leadership in the luxury EV space.
Historically, battery technology transitions have followed unpredictable timelines. Lithium-ion batteries, first commercialized by Sony in 1991, took nearly two decades to dominate consumer electronics before transforming automotive. Similarly, Toyota first demonstrated solid-state battery prototypes in 2010 but only now commits to production dates. This pattern suggests that while announcements generate headlines, real-world deployment depends on solving hundreds of manufacturing challenges unseen in lab environments.
The current ASSB race mirrors the 2010s lithium-ion density wars, where Tesla’s 2012 Model S 85kWh pack (265 Wh/kg) seemed revolutionary until CATL achieved 300+ Wh/kg by 2020. Today’s 500 Wh/kg semi-solid-state batteries may represent a similar stepping stone, buying time for true solid-state solutions to mature. As BMW’s extreme testing shows, the path to 600-mile EVs remains fraught with thermal and electrochemical hurdles that no single breakthrough can overcome.
