Mercedes-Benz Testing Solid-State Battery to Get EQS a 621-Mile Range

The Mercedes-Benz EQS is the all-electric version of the S-Class, the marque’s flagship product which also tends to get all the best that the automaker has to offer first. Soon, that might include a solid-state battery that gives the car a whopping 621 miles of range.

The lithium-metal solid-state battery is currently being tested by Mercedes, first last year in a lab in Stuttgart where Mercedes is based, and then, this month, on the road. Mercedes thinks the new battery…