The batteries are from Mercedes-AMG's Formula 1 cars, these being the MGU-K and the MGU-H. The MGU-K is installed on the main driveshaft; its purpose is to help spin the rear wheels and recover kinetic energy while braking.
The batteries are from Mercedes-AMG's Formula 1 cars, these being the Motor Generator Unit-Kinetic (MGU-K) and the Motor Generator Unit-Heat (MGU-H). Its purpose is to help spin the rear wheels and recover the same kinetic energy while braking.