Woah, Merc’s prototype solid-state battery gives the EQS 621 miles of range

Mercedes has modified an EQS to test its prototype lithium-metal solid-state battery and the results are already looking really promising, taking range from 488 to a theoretical 621 miles.

The succinctly named Mercedes-Benz Centre for Competence for Battery Systems is working with battery cell manufacturer Factorial and the AMG High Performance Powertrain guys (yep, the same guys responsible for F1 tech). Their 'slightly modified' EQS Sedan is expected to get 25 per cent more range compared to a current battery of the same weight, and will be able to manage charging cycles better, too.

That's because on top of the 450Wh/kg target power density, volume-monitoring pneumatic actuators (or in regular person talk, air cushions) have been fitted to protect the battery.

While solid-state batteries are lighter and safer (tantamount to the Holy Grail of battery innovation), the rigidity of the solid electrolyte means a greater potential for it to break. Unlike liquid or gel found in today's batteries which have a bit of give when the electrolyte gets warmer and expands, the solid one, erm, doesn't. That's where the air cushions come in, managing the space during expansion and contraction.

Merc reckons it'll get additional weight savings and more energy efficiency as it works to cool the battery, and says there'll be further insight gleaned over the next few months as testing continues. More as we have it.