Sustainable Regeneration of Spent LiFePO ₄ Cathode with Al‐Doping

With the popularity of electric vehicles, the number of used lithium iron phosphate (LiFePO 4 , LFP) batteries has increased significantly, and failure to properly dispose of these end‐of‐life power batteries will cause serious harm to the environment. In this study, an environmentally friendly and efficient solid‐phase method is proposed to regenerate spent LFP cathode materials. In this method, the crystal structure of LFP cathode materials is restored by supplementing lithium using a lithium source, Fe 3 + impurities in LFP are reduced using glucose, and the regenerated materials are carbon coated. In addition, Al 3 + is introduced to dope the regenerated LFP to further enhance its repair effect. The test results show that the Al 3 + ‐doped regenerated LFP material has a low electrochemical impedance, and its discharge‐specific capacity reaches 148.59 mAh g −1 at a 0.05 C multiplication rate, which is about 93.38% of the discharge‐specific capacity of the new LFP (N‐LFP). The capacity retention rate reaches 89.02% after 500 cycles at 1 C multiplication rate. These data indicate that the doped and regenerated LFP material exhibits an excellent capacity recovery rate and cycling stability. This study provides a new route for the recycling of waste LFP cathode materials.