Four minutes and 37 seconds. That’s how much time it took for Nyobolt’s working EV prototype to top up its batteries from 10% to 80% charge using a 350-kilowatt DC fast charger.

Polestar quantifies it as a 10-to-80-percent charge in 10 minutes on the prototype battery pictured above. The XFC cells are designed to work with 350-kW fast-charging for full optimization.

The prototype Polestar 5 uses an “Extreme Fast Charging” 77kWh EV pack, created in conjunction with company StoreDot, that can add 200 miles of range in 10 minutes. A Tesla would take about 15 ...