FABRICATING METHOD OF LIFEPO4 CATHODE ELECTROACTIVE MATERIAL FOR LITHIUM SECONDARY BATTERY BY RECYCLING, LIFEPO4 CATHODE ELECTROACTIVE MATERIAL FOR LITHIUM SECONDARY BATTERY, LIFEPO4 CATHODE AND LITHIUM SECONDARY BATTERY FABRICATED THEREBY

摘要

PURPOSE: A manufacturing method of a LiFePO4 positive electrode active material is provided to reduce costs and to prevent air pollution by using a positive active material that a positive electrode scrap is recycled or retreated. CONSTITUTION: A manufacturing method of a LiFePO4 positive electrode active material comprises a step of heat-treating LiFePO4 positive active material-containing positive electrode scraps (S1); a step of collecting LiFePO4 positive active material by separating a current collector from the positive electrode scraps (S2); a step of heat-treating the LiFePO4 positive active material (S3); a step of dissolving the LiFePO4 positive active material in an acid solution and precipitating FePO4 by injecting ammonia water into the solution (S4); a step of obtaining FePO4 solid contents by filtering the solution (S5); a step of obtaining crystalline FePO4 or Fe2P2O7 by heat-treating the FePO4; and a step of mixing a lithium compound and a carbon source into the FePO4 or Fe2P2O7, and heat-treating the mixture to manufacture the LiFePO4 positive active material (S7). [Reference numerals] (AA) LiFePO4 positive active material; (S1) Heat-treat LiFePO4 positive electrode scraps; (S2) Separate a current collector; (S3) Heat-treat LiFePO4 positive active material in the air; (S4) Dissolve in an acid solution and inject ammonia water into the solution - Precipitate FePO4; (S5) Filter the precipitate; (S6) Heat-treat FePO4 precipitate in the air or hydrogen - crystallize into FePO4 or Fe2P2O7; (S7) Mix and heat-treat a lithium compound to satisfy Li:Fe=1:1