Optimized Charging Method for Fast Charging of EV Batteries

Nowadays, energy storage plays a crucial role in electric vehicles. The existing constant current constant voltage charging methods can accelerate damage inside the battery by causing a loss of lithium ions, if a high current (more than 1C) is injected. Hence, a new optimized charging algorithm is proposed in this paper. In this charging method, four charging algorithms are combined, which are pulse current charging (0% to 20% SOC), pulse and burp current charging (20% to 80% SOC), and constant current constant voltage charging (above 80% SOC). This proposed hybrid charging algorithm reduces the charging time to less than an hour. One of the important features of this charging algorithm is that it charges the battery in pulse charging and pulse and burp charging modes at low frequency (2.5 Hz). Additionally, the negative current pulse in pulse and burp charging mode helps to mitigate the issue of lithium plating on the surface of the negative electrode during the charging process. Hence, the proposed method optimizes the performance of the battery to improve the battery life. The proposed algorithm is implemented in a bidirectional DC-DC power converter to verify the operation. The simulation and experimental results of the proposed charging method are included in this paper which shows, improvement of the battery life. The experimental results are also included in this paper.