September 10, 2025 - Mercedes-Benz Sets Record With Solid State Battery

This is the Telemetry Transportation Daily for September 10, 2025 and I'm Sam Abuelsamid, Vice President of Market Research for Telemetry.  

Solid-State batteries are one of those intriguing technologies that have been just over the horizon for many years now. But perhaps, they might really be coming into focus by the end of this decade. 

The promise of solid-state cells is that they will offer nearly double the energy density of current technologies, essentially eliminate thermal runaway and reduce cost. It's like the classic game of three choices cheap, fast and good where you could have any two. But solid state cells might just provide all three. The key to these cells is they eliminate the liquid or gel electrolyte material between the anode and cathode with a solid material that eliminates the possibility of the electrodes short circuiting. Unfortunately, while many developers have shown off small cell prototypes, everyone has struggled with scaling the manufacturing of these cells. 

Mercedes-Benz is one of several automakers working with Massachusetts based Factorial Energy. Mercedes has installed full-scale battery pack with Factorial's prototype cells into an EQS sedan. The pack was co-developed with Mercedes-AMG High Performance Powertrains, the automaker's Formula 1 engine unit. The cells use lithium metal anodes which eliminate the need for graphite, one of the costlier materials in a cell. Engineers drove the car from Stuttgart to Malmo Sweden, a distance of 749 miles on a single charge, surpassing a previous record set by the company's Vision EQXX concept. 

Because the lithium metal cells expand and contract, during charging and discharging, the pack is equipped with pneumatic actuators that maintain a constant contact pressure in the cells. Even with this extra hardware the pack has 25% more capacity than the standard production unit of the same size. 

While this was a useful real world validation of performance, Factorial and its partners still need to demonstrate that they can manufacture cells at industrial scale and lower cost than current technologies, thus we still won't be buying solid state battery EVs until at least late this decade.