| abstract |
A method for preparing lithium iron phosphate cathode materials by recycling waste lithium iron phosphate batteries. 1) Soak the waste lithium iron phosphate battery in salt water, disassemble it after fully discharging, and obtain the positive and negative pole pieces; 2) After the pole pieces are crushed, frozen, soaked in boiling water, and vibrated and sieved, the active materials and Copper foil, aluminum foil; 3) Vacuum roasting of the sorted active material; 4) Acidic leaching of the active material after vacuum roasting to obtain a solution containing Li, Fe, P and insoluble slag; Copper and aluminum phosphate precipitation to remove aluminum, remove the remaining copper impurities and aluminum impurities; 6) Add lithium source and phosphorus source to the leaching solution and perform hydrothermal reaction to obtain regenerated lithium iron phosphate material; 7) Mix in After the carbon source, high-temperature calcination treatment is carried out to obtain a carbon-coated lithium iron phosphate positive electrode material. The invention has a short process flow, excellent electrochemical performance of the regenerated lithium iron phosphate cathode material, and effectively utilizes valuable elements in waste lithium iron phosphate batteries. |