Research on Variable Voltage-Constant Voltage Phased Pulse Charging Method for Lithium Batteries Based on Fuzzy Algorithm

The charging process of lithium battery will be affected by many factors, and the conventional charging method does not fully consider all the influencing factors in the charging process of lithium battery, so it is generally difficult to achieve the optimal charging effect. In this paper, based on the research of conventional fast charging method, it is improved and a variable voltage-constant voltage phased pulse charging method is proposed. Through the optimized fuzzy controller to control it, the voltage deviation and the change rate of voltage deviation are input, and the charging current is output, a two-input and one-output fuzzy controller is designed. The simulation results show that no matter what the initial SOC of the battery is, the charging time and energy consumption can be improved by using the proposed variable voltage-constant voltage phased pulse charging method for lithium batteries based on fuzzy algorithm. The proposed method of step-by-step pulse charging of lithium battery with variable voltage and constant voltage based on fuzzy algorithm can obviously shorten the charging time compared with variable frequency pulse charging, which shows that the optimization of step-by-step pulse charging of lithium battery with variable voltage and constant voltage based on fuzzy algorithm can improve the charging time and charging life at the same time.