According to the charging trigger information or the power supply trigger information, the charging and discharging state is matched from a state database, so that the charging and discharging state information is matched, the state database is a preset database, and is identified by comparing the state information.

Step 103, if a plurality of lithium batteries 300 corresponding to the highest electric quantity are provided, then sort charging or discharging time points of the lithium batteries 300, and preferentially charging and discharging the lithium battery 300 with the longest time point from the current time point.

Once a plurality of lithium batteries 300 corresponding to the highest electric quantity are provided, the time points of charging or discharging of the selected plurality of lithium batteries 300 are sorted, and the lithium battery 300 having the longest time point from the current time point, i.e., the lithium battery 300 having the longest time point is charged and discharged preferentially, so that the temperature rise is reduced.