METHOD FOR REPAIRING SURFACE STRUCTURE OF HIGH-NICKEL POSITIVE ELECTRODE MATERIAL, HIGH-NICKEL POSITIVE ELECTRODE MATERIAL OBTAINED THEREFROM, AND LITHIUM ION BATTERY

摘要

Provided by the present application are a method for repairing the surface structure of a high-nickel positive electrode material, a high-nickel positive electrode material obtained therefrom, and a lithium ion battery. The method comprises: mixing a high-nickel positive electrode material, a first lithium source and a metal oxide, and then sintering to obtain a sintered product; and mixing the sintered product with an acid solution for reaction, and then evaporating and sintering to obtain a high-nickel positive electrode material that has a repaired surface structure. In the method of the present application, first the first lithium source and the metal oxide undergo compound reactions with nickel oxide and residual lithium on the surface of the material respectively, part of the impurity phase on the surface of the material is removed, and a protective layer is formed on the surface of the material. Then, a weak acid is used to further remove the impurities on the surface of the material, and a lithium ion conductor coating layer is formed on the surface of the material. Not only are the discharge capacity and first effect of the battery improved, but the cycle performance and safety performance are also improved.