Two-stage constant current charging methodThe first stage is the high-current constant-current charging. The charging current acceptable by the battery in the early stage of charging is large, so the high-current constant-current charging is adopted to make the battery obtain most of the power. With the charging process, the acceptable charging current of the battery decreases continuously. When the terminal voltage of the battery reaches the set value, the battery enters the charging stage of small current and constant current. The charging effect of two-stage constant current charging method is better than that of constant voltage or constant current charging method, but it is only a rough simulation of mas curve, but it is not up to the requirements of high performance and quick charging of battery.