Electrolytic capacitors are mainly related to the electronic system and power management of vehicles, which are used as energy storage devices to recover and store braking energy and release energy when necessary to provide additional power support. This is helpful to improve fuel efficiency and reduce emissions. In the battery management system, the voltage difference in the battery pack is balanced to ensure the stability and life of the battery pack. In the automobile starting system, when extra current is needed at the starting moment. They help to ensure that the engine gets enough power when it is started, and can also smooth the voltage and current of the motor drive system, provide transient high current support, and enhance the starting and acceleration performance. In addition, the supercapacitor is a special type of electrolytic capacitor with extremely high capacitance and fast charging and discharging ability. It can start the auxiliary power system, provide high power output for a short time, and relieve the battery load. It is also widely used in vehicle-mounted electronic equipment such as vehicle-mounted entertainment system and navigation system, mainly to smooth power supply voltage, filter noise and provide temporary power supply support.