Mercedes Begins Testing Solid-State Battery Prototypes

Solid-state batteries are expected to be the future of EVs, but they have proven difficult to develop and manufacture on anything close to a commercial scale. Mercedes appears to be moving ahead of the curve, as its first solid-state EV prototype recently hit the streets for testing.

The prototype battery powers a Mercedes-Benz EQS sedan and was developed in partnership with Factorial Energy. The automaker expects the battery to reach 620 miles on a charge, a more than 25 percent boost over the WLTP estimates for the current EQS. That said, WLTP standards are more forgiving than the EPA’s, so the U.S. will likely see lower range numbers if and when the batteries arrive here.

Solid-state batteries promise a huge improvement over the lithium-ion and similar battery packs we have today. They trade the liquid electrolyte for a solid material that makes the batteries safer, more stable, and more energy efficient, allowing them to deliver longer range numbers with a smaller, lighter footprint.

The batteries Mercedes is testing use Formula 1 technology to cope with expansion and contraction that occurs with charging and discharging. It also appears that the automaker and its battery partner have made progress with some of the challenges involved in solid-state technology, including some of the chemistry issues that can cause shorts in the pack.

Despite this step forward, solid-state batteries are still several years off from a commercial rollout at the earliest. Designing and making the technologies work is one thing, but adapting them to safety and road standards is another beast altogether. At least we’re seeing progress.

[Image: Mercedes-Benz]

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