Mercedes and Factorial working on solid state batteries with 80% better range

Mercedes-Benz and US battery start-up Factorial are working on a solid state battery that should ‘dramatically’ improve range and cut costs for electric vehicles.

The two firms said they planned to have the new technology – named Solstice – in production by the end of the decade and claimed it could offer an 80% range increase over that currently offered by lithium-ion.

Solid state batteries are seen as the next major breakthrough for EVs, offering far greater energy density, faster charging, better long-term durability and reduced risk of fire and thermal runaway. They could also bring cost savings in production which could make EVs more affordable.

Several other manufacturers, including Nissan and Toyota plan to introduce solid state batteries in the next three to four years but the technology is proving harder than expected to produce at the scale needed for mainstream distribution.

Germany’s Mercedes-Benz invested in Factorial in 2022, alongside Stellantis and Hyundai.

Factorial has already developed a quasi-solid-state battery which car makers are testing and could appear in road cars by 2026. The semi-solid-state batteries are seen as an important stepping stone because they can be made on similar production lines to existing lithium-ion batteries. Factorials CEO Siyu Huang told Reuters that this meant production could be scaled up more quickly.

Huang also said that solid state batteries could bring major cost savings for car makers as they do not require the heavy and expensive cooling systems of today’s cells. She said: “We’re not just focused on the cost of the cell, but the cost of the overall vehicle.”

Mercede-Benz chief technology officer Markus Schaefer said that the solid state batteries could provide energy density of 450 Watt-hours per kilogram – a 40% improvement over its existing high performance batteries.

He said that would allow the brand to either offer even longer-range vehicles or to significantly cut the battery pack size, saving money and weight. This could in turn allow it to use cheaper steel for body construction instead of more expensive but lighter aluminium.

“There are some challenges that you have to get under control, but … we have great engineering solutions to address them,” Schaefer said.