Abstract:At present, most electric vehicle charging devices have limited output power and the charging methods used are relatively simple, which causes problems such as long charging time, high energy consumption and high temperature rise in the charging process of electric vehicles. In order to solve these problems, this paper designs a high-power charging equipment and proposes a multi-stage current charging method for electric vehicles based on the optimal charging curve, and this charging method is applied to the high-power charging equipment. Firstly, the electrical structure diagram of the high-power charging equipment is designed; secondly, the implementation process of the multi-stage current charging method is given according to the charging characteristics of the power battery; then, the experimental comparison and analysis with the traditional constant current charging method and constant current and constant voltage charging method are conducted on the high-power charging equipment. The results show that the multi-stage current charging method can shorten the charging time by more than 5% compared with the traditional 1C constant current charging and 1C constant current and constant voltage charging methods, reduce the charging temperature rise by more than 50% compared with the traditional 2C constant current charging method and 2C constant current and constant voltage charging, and make the battery capacity reach 80% in a relatively short time , which can meet the requirements of fast charging of electric vehicles. Therefore, the method proposed in this paper can balance the charging time and charging temperature rise of electric vehicle power battery, prolong the service life of electric vehicle power battery, and have better overall performance.