Polestar and fast-charging battery company StoreDot have successfully demonstrated the implementation of StoreDot’s Extreme Fast Charging (XFC) technology in a car for the first time, charging a Polestar 5 prototype from 10% to 80% in just 10 minutes. The fully drivable verification prototype saw a consistent charge rate starting at 310 kW and rising to a peak of more than 370 kW at the end of charging.
This world-first demonstration of a 10-minute 10-80% charge using silicon-dominant cells in a drivable vehicle — rather than individual cells in a laboratory environment — is the continuation of Polestar’s commitment to developing the best driving through innovative technology partnerships. The specially commissioned 77-kWh battery pack has the potential to be increased to at least 100 kWh and could add 200 miles (320 km) of range to a mid-size electric car in 10 minutes.
This XFC test by Polestar and StoreDot battery engineers was designed to demonstrate proof-of-concept for XFC battery technology that could be applied to future Polestar vehicles.
“Time is one of life’s greatest luxuries, and as a manufacturer of luxury electric performance cars, we need to take the next step to address one of the biggest barriers to EV ownership: charging anxiety,” says Thomas Ingenlath, Polestar CEO. “With this new technology, on longer journeys when drivers do stop, they’ll be able to spend less time charging and be back on the road faster than before. In fact, that stop time will be more akin to what they experience with a petrol (gasoline-fueled) car today.”
StoreDot’s XFC technology uses silicon-dominant cells with an energy density on par with state-of-the-art NMC cells and does not require specialist cooling systems in the vehicle. The experimental XFC battery’s modules have a structural function that improves mechanical properties and cooling ability while maintaining or reducing weight levels, with high recyclability and serviceability also paramount in the design of the pack.
In commercial EV batteries, fast-charging rates can vary greatly depending on the battery’s state of charge (SOC), sometimes dropping significantly as SOC increases. During this test, Polestar saw charging speed rise from 310 kW at 10% SOC to over 370 kW at 80% SOC, proving the technology’s steady charging rate with no significant change in charging speed or efficiency whenever a driver decides to stop within this SOC range.
The test proves XFC technology works with the current DC charging infrastructure, which continues to feature more high-power DC chargers of 350 kW or higher.
A film showing the testing procedure can be found here.