METHOD FOR SELECTIVE OXIDATION-REDUCTION REGENERATION FROM WASTE LITHIUM IRON PHOSPHATE, REGENERATED LITHIUM IRON PHOSPHATE, AND LITHIUM ION BATTERY

摘要

The present disclosure discloses a method for recycling waste lithium iron phosphate by selective oxidation-reduction, recycled lithium iron phosphate, and a lithium ion battery. The method includes: primarily sintering waste lithium iron phosphate under a condition where a mild oxidizing gas is introduced; separating a lithium iron phosphate powder material; supplementing lithium and supplementing carbon to the lithium iron phosphate powder material and regulating the composition of the lithium iron phosphate powder material using a lithium source and a carbon source by means of secondary sintering to obtain recycled lithium iron phosphate, wherein the mild oxidizing gas is water vapor, CO₂ gas, or a mixed gas thereof. Lithium iron phosphate with excellent performance can be prepared by the method of the present disclosure and exhibits electrochemical performance characterized by perfect cycle performance at room temperature and at high temperature, and high compacted density. Moreover, this material also has the advantage of low cost.