Hybrid Operation of Super-Capacitor and Battery Storage to Improve Electric Vehicles Performances

Abstract

This paper proposes a method for battery storage and supercapacitor (SC) hybrid operation toward improving EVs' performance. The adopted concept is established to regulate the level of charge for the SC to suit the immediate storage needs of the EV in such a way as to couple both storage devices. The results demonstrate that the current drawn from the battery has significantly reduced the discharging rate of the battery smoothed out compared to the EV without the SC. Also, the electric vehicle (EV) battery capacity is improved and the implementation of an SC eliminates the abrupt discharge of state of charge (SoC). The SC supports the EV by providing the necessary power when required. The simulation results demonstrate the contribution of SC to improving the battery performance and the reduction in discharging rate. The battery cannot be disconnected, while the SC could be, and power can be exchanged via supercapacitor. The SC is faster than the battery to maintain the optimum SoC level during the tested time (20 sec) at a level of approximately 50%. The obtained results indicate the charging of the SC during the acceleration only. By enhancing the EV stores and transferring its power flows using the proposed hybrid storage system, a more efficient EV can be developed to reduce the frequency of EV battery charging.