| abstract |
The invention relates to a method for repairing waste and old lithium iron phosphate materials, comprising the following steps: 1) determining the content of Li, Fe and P elements in the waste and old lithium iron phosphate materials; 2) configuring a mixed solution containing lithium salts, iron salts and phosphoric acid, Add the waste lithium iron phosphate material to the mixed solution according to the final stoichiometric ratio Li:Fe:P=0.75～1.25:1:1, stir and mix, and use ammonia water to control the pH value of the mixed solution to 5.5～ 8.5 Obtain a mixture; 3) hydrothermally react the mixture at 100°C to 200°C to obtain a lithium iron phosphate precursor; 4) perform a carbon coating reaction on the lithium iron phosphate precursor at a temperature of 650°C to 800°C The repaired lithium iron phosphate battery material is obtained. The method realizes the direct repair of the cathode material of the waste lithium iron phosphate battery. |