BYD unveiled a new fast charging system which may charge cars in less than a third of the time Tesla’s current chargers allow, while Zeekr said it will offer its self-driving system for free in China.

The system can cool and heat without using volatile refrigerants or burning fossil fuels by exploiting the “elastocaloric effect” in nickel-titanium (Ni-Ti) shape memory alloys. Dubbed elastocalorics, ...