Mercedes-Benz is developing very juicy solid-state batteries with 80 per cent more EV range

For over a year, Mercedes-Benz has been collaborating with a company called Factorial Energy and together, they’ve refined the Solstice. And the Solstice will help Mercedes-Benz in its aims to have solid-state batteries in its cars by 2030.

Solstice. Not the bi-annual festival of the earth's movement or a tragic old Pontiac, but the name of this solid-state battery that features 450 watt-hours-per-kilogram (Wh/kg) power density. Judging by the picture of the cell above, each looks about the size of a foil pack of football cards. Surely not?

For context, your current fully electric or hybrid car battery chemistry has a density of, at best, 255Wh/kg. At worst? As little as 90Wh/kg. Unsurprisingly then, Mercedes and Factorial reckon the Solstice will enable EVs to go 80 per cent further.

The 100+Ah nickel-metal solid-state batteries use Factorial’s proprietary platform, 'Factorial Electrolyte System Technology', or FEST. That features a lithium-metal anode, a sulfide-based electrolyte and a dry cathode.

The chemistry minimises fire risk, because there’s no flammable, volatile liquid electrolyte, and that also offers greater temperature stability. Not only are there fewer cooling requirements for the battery pack, but we’re told manufacturing the technology fits into existing production facilities, too.

Markus Schäfer, CTO of Mercedes Benz, said: “Solstice offers further improvements in energy density and safety features that will help us develop electric vehicles that set new standards in range, cost, and performance.”

It's worth noting that Factorial has the financial backing of Hyundai and Stellantis as well.