| 摘要 |
The present invention relates to a multistage charging method and a multistage charging device for secondary batteries. The multistage charging method for the secondary batteries comprises: a high current discharge step (S100) of discharging a current with a current amount greater than a standard current amount of the secondary batteries until the voltage of secondary batteries to be charged reaches a predetermined discharge completion voltage; a boost charging step (S200) of charging the second batteries to a predetermined voltage with a current amount higher than a standard current amount of the secondary batteries once the high current discharge is completed; a pulse charging step (S300) of charging the secondary batteries until the secondary batteries are fully charged to a pulse current having a certain interval once the boost charging is completed and stopping the charging during a predetermined time period; and a constant voltage charging step (S400) of performing a constant voltage charging process until the voltage of the secondary batteries reaches a full-charge voltage once the pulse charging is completed or the charging current becomes smaller than a predetermined current. The present invention is designed to provide the multistage charging method and the multistage charging device for secondary batteries including a process of combining various charging methods and a discharging process to improve the output characteristic, in particular, a charged initial voltage maintenance rate by improving the charging method of secondary batteries. |
