Graphene secret to Mercedes F1 power
Under braking, the MGU-K (electric motor) operates as a generator, recovering some of the kinetic energy dissipated during braking. It converts this into electricity that can be stored in the battery and deployed throughout the lap (limited to 120 kW or 160bhp by the rules). Under acceleration, the MGU-K is powered from the Energy Store (battery) and/or from the MGU-H and acts as a second motor to help propel the car.
If our sources are correct, this explains Mercedes huge power advantage. Not only peak power, but the fact that it can charge and recharge its battery/ultracapacitor over and over during a single lap while the hapless Lithium Ion batteries are lucky to complete one full cycle of charge and discharge. This means coming out of every corner, with its ultracapacitor fully recharged under braking for the previous corner, the Mercedes always has the full extra 120 kW or 160bhp available to assist the internal combustion engine.
It would not surprise us one bit if the battery given to the Mercedes engine customer teams are Lithium Ion batteries while Mercedes uses graphene in its battery.
The video below explains how all the components of a F1 power unit work in harmony.