This is the source of electricity in the car and the conversion process between battery and generator power. In this process, the main power supply is the generator, and the battery only provides electric energy when the engine is turned off and the initial start. In the normal operation of the engine, if the generator power is not enough to meet the electric demand of the car, the battery will also assist the generator power supply. For example, some small displacement engines, at low speed operation, if the headlights and other high-power electrical appliances are opened at the same time, the generator load is too large, the operation resistance is too large, it will react on the engine, the engine will shake seriously. At this point, the battery will participate in the power supply, to avoid the overload of the generator and engine stalling. In addition, if the car often travels a short distance at a low speed, the electric energy of the battery is not enough to supplement, it will also lose power, at this time, it is necessary to use external power to supplement the battery charge.
