RECYCLED CATHODE ACTIVE MATERIAL, METHOD FOR RECYCLING CATHODE ACTIVE MATERIAL, AND SECONDARY BATTERY COMPRISING SAME

The present invention relates to a recycled positive electrode active material, a method of recycling a positive electrode active material, and a secondary battery including the recycled positive electrode active material. More particularly, the present invention relates to a recycled positive electrode active material including one or more selected from the group consisting of a lithium nickel oxide (LNO)-based positive electrode active material, a nickel-cobalt-manganese (NCM)-based positive electrode active material, a nickel-cobalt-aluminum (NCA)-based positive electrode active material, and a nickel-cobalt-manganese-aluminum (NCMA)-based positive electrode active material, including 60 mol% or more of Ni, and containing crystalline LiF, a method of recycling a positive electrode active material, and a secondary battery including the recycled positive electrode active material.According to the present invention, the present invention has an effect of providing a positive electrode active material prepared by firing a waste positive electrode containing a high-nickel (Ni) positive electrode material at a predetermined temperature, adding a lithium precursor immediately after the firing without a washing process, and performing annealing so that predetermined crystalline LiF is contained on the surface of a recycled positive electrode active material and the amount of residual lithium is controlled; and having excellent initial discharge capacity, rate performance, capacity characteristics, and resistance characteristics. In addition, the present invention has an effect of providing a method of recycling a positive electrode active material, characterized in that eco-friendliness is secured by not using acids in recovery and recycling processes; process cost is reduced because neutralization and wastewater treatment are not required accordingly; no metal element is discarded by recycling a positive electrode active material in an intact state without disassembling the positive electrode active material; the risk of toxic gas generation or explosion is excluded by not using an organic solvent; and economic feasibility and productivity are greatly improved by omitting a washing process.