In the automotive industry, the application of an intelligent start-stop control system (light hybrid system) provides a broad stage for supercapacitors, especially in plug-in hybrid vehicles.  Due to the frequent starting and stopping of electric vehicles, the discharge process of the battery has changed greatly.
During normal driving, the average power drawn by the electric vehicle from the battery is quite low, and the peak value during acceleration and climbing is quite high. Under the existing technical conditions of electric vehicle batteries, the battery must balance between specific energy and specific power and specific power and cycle life, and it is difficult to pursue high specific energy, high specific power and long time on an energy system. life. In order to solve the contradiction between the continuous driving range of electric vehicles and the acceleration of climbing performance, two sets of energy systems may be considered, in which the main energy source improves the optimal driving range, and the auxiliary energy provides a short time when accelerating and climbing.
Auxiliary power. The energy of the auxiliary energy system can be directly obtained from the independent energy, or the renewable kinetic energy can be recovered when the electric car brakes or downhill, and the super capacitor is used as the auxiliary energy. In the short term, the extremely low specific energy of supercapacitors makes it impossible to be used alone as an energy system for electric vehicles, but it has significant advantages as an auxiliary energy source.
The best combination used in electric vehicles is the battery-supercapacitor hybrid energy system, which requires separate specific energy and specific power for the battery. Supercapacitors have a load-balancing effect. The discharge current of the battery reduces the available energy and the service life of the battery. The supercapacitor can quickly and efficiently absorb the regenerative kinetic energy generated by electric vehicle braking compared with the battery. The supercapacitor's early and balanced and energy recovery effects greatly improve the driving range of the vehicle. However, the system must do comprehensive control and optimal matching of batteries, super capacitors, motors, and power inverters. The design and application of power converters and controllers should fully consider the matching between motors and super capacitors.