Abstract: The spent LiFePO4 cathode materials were re-synthesized by adding different amount-of-substance fraction of Li2CO3 in solid phase method after high temperature purification treatment.The electrochemical test results showed that the re-synthesized cathode materials can effectively make up for the loss of reversible lithium by adding suitable amount of 10% （amount-of-substance fraction） of Li2CO3 and 25%（mass fraction） glucose and exhibited excellent electrochemical performance as cathode materials.Their specific discharge capacity can reach 159.6 mA·h/g at 0.1C，and 86.9 mA·h/g even at 20C.After 1 000 cycles at 10C，they still have a high capacity retention rate of 91%.This work showed that this method can effectively improve the electrochemical performance of spent cathode material and provided an effective route for large scale recovery and reuse of spent LiFePO4 cathode materials in lithium-ion batteries.

Key words: spent lithium ion battery, lithium iron phosphate, lithium refilling, regeneration, electrochemical property