A method for pre-determining the optimal remanufacturing point of lithium ion batteries

A new way to determine the optimal remanufacturing point of lithium ion batteries for electric vehicle has been proposed in this paper. The proposed optimal remanufacturing point can avoid the sharp degradation stage of battery and ensure most of active materials covered in electrodes reused in remanufacturing process with modest cost and energy. In order to find out the optimal remanufacturing point in our experiment, the charge-discharge cycle of lithium ion batteries was carried out by using battery testing system and internal resistance meter, which can obtain enough data such as the degradation of capacity, the change of internal resistance, the charging and discharging rate and the cycle life of battery for analysis. Then the optimal battery's remanufacturing point about 500-550 cycle times has been found.