As the discharge is shallower, the number of cycles will increase greatly. Therefore, according to this theory, frequent charging is beneficial to cycle life. However, as far as a large number of chargers are used in the market, due to price factors and technical level, the charger has a high failure rate, poor reliability, and accuracy. Low-level defects. Therefore, sometimes charging frequently will affect the service life of the battery. When the battery is discharged and recharged, although the number of recharges is reduced, there will always be differences between the single cells during discharging, which may cause some single cells to be over-discharged. The over-discharge battery charge acceptability will be greatly reduced, causing undercharge faults. In addition, Since the charger is recharged after the power is discharged, the charger has a heavy load for a long time and is easy to damage the charger. Therefore, based on the above, we believe that it is more reasonable to charge the battery once when it discharges 50-70% of the power, which is beneficial to the use of the battery.