Mercedes-Benz is testing a solid-state battery in the EQS

For some time now we have been told that solid-state battery technology is set to mark a before and after in the electric mobility sector. A future that is getting ever closer, as evidenced by the growing number of manufacturers starting to work with this type of battery.

Mercedes-Benz is one of those manufacturers already considering the use of this type of battery in its electric models. According to a recent report, the German manufacturer has begun performance tests of a solid-state battery in a modified EQS unit. The brand’s engineers are apparently working in collaboration with Factorial Energy, a US company specialising precisely in this battery technology.

Over the coming weeks, the Stuttgart-based company plans to gather data on the efficiency, durability and performance of this battery. According to reports, with a solid-state battery like this one, the EQS could reach up to one thousand kilometres on a single charge, a substantial increase in range over the 450+ version currently on sale for this luxury saloon, which can cover 822 km under the WLTP homologation cycle.

Integrating this solid-state battery into the EQS has not, however, been a simple task. According to reports, the German manufacturer has been forced to make some adjustments to the housing intended to accommodate the battery pack. Everything points to Mercedes-Benz currently testing cells supplied by Factorial with an energy density of 391 Wh/kg.

This is only the beginning

The two companies plan to collaborate, however, on a much more ambitious project in the future. Factorial Energy will supply Mercedes-Benz, on a date yet to be determined, with new cells called Solstice, with an even higher energy density that will reach 450 Wh/kg. Using these cells in an EQS would mean a range increase of close to 80 per cent over what it offers today, meaning almost 1,500 km covered on a single charge. Something that already seems almost excessive.

This research and development effort by Mercedes-Benz reflects the company’s commitment to leading the transition towards more efficient electric vehicles with greater range, at a time when car manufacturers are seeking solutions to overcome the limitations of current battery technology.

Solid-state batteries promise significant advantages over today’s lithium-ion batteries, offering more range with a similar size and weight. But that is not all, as they will allow much shorter charging times, will be safer by not using flammable liquid electrolytes, and their service life will also be longer.