How does the Audi e-Tron charge on the go?

I have heard that the Audi e-Tron has regenerative braking, but I am confused about how it charges when driving. Can anyone explain the charging process when driving on the road?

The Audi e-Tron has a sophisticated regenerative braking system that can recover up to 30% of the car's kinetic energy while driving. This energy is then stored in the battery for later use. It's a great feature that helps to extend the car's range and reduce the need for frequent charging.