Abstract: A high-nickel ternary core-shell precursor for a lithium battery, a positive electrode material and a preparation method therefor. The chemical structural formula of the precursor is zNi(C4H7N2O2)2—Nix-zM1yM21-x-y(OH)2, wherein M1 and M2 are two of cobalt, aluminum, and manganese. The preparation method comprises: pumping a prepared metal salt solution, a dimethylglyoxime-ammonia water composite solution, and an ammonia water solution into a reaction kettle, maintaining the pH of a reaction system, and controlling the reaction time to obtain a sphere-like precursor inner core with a structural formula of Ni(C4H7N2O2)2; pumping the metal salt solution and the ammonia water solution, stopping pumping the dimethylglyoxime-ammonia water composite solution, pumping a sodium hydroxide solution to obtain a sphere-like core-shell precursor, washing, drying, sieving and deironing the precursor, mixing with a lithium source, and calcining to prepare the positive electrode material.

Abstract: The present invention provides a method of preparing an MOF-coated monocrystal ternary positive electrode material. Firstly, a solution A of nickel, cobalt and manganese metal salts, an ammonia complexing agent solution and a caustic soda liquid are added to a reactor for reaction to obtain a precursor core; then, an organic carboxylate is dissolved in an amount of an organic solvent to obtain a solution B; the solution B and a manganese metal salt solution with a given concentration are added to the reactor and aged to obtain an MOF-coated core-shell structure precursor; the core-shell structure precursor is pre-sintered at a low temperature to obtain a nickel-cobalt-manganese oxide with monocrystal structure; the nickel-cobalt-manganese oxide with monocrystal structure is uniformly mixed with LiOH·H2O in a mortar and then calcined at a high temperature to obtain an MOF-coated monocrystal ternary positive electrode material.

Abstract: Provided are a battery-level Ni—Co—Mn mixed solution and a preparation method for a battery-level Mn solution, the steps thereof comprising: acid dissolution (S1), alkalization to remove impurities (S2), synchronous precipitation of calcium, magnesium, and lithium (S3), deep ageing to remove impurities (S4), synergistic extraction (S5), and refining extraction (S6). The steps of deep ageing to remove impurities (S4) and synergistic extraction (S5) comprise: performing deep ageing on a filtrate obtained from the step of synchronous precipitation of calcium, magnesium, and lithium (S3), and after performing filtration to remove impurities, obtaining an aged filtrate; using P204 to extract the aged filtrate and obtain a loaded organic phase, and subjecting the loaded organic phase to staged back-extraction to obtain the battery-level Ni—Co—Mn mixed solution and a Mn-containing solution.

Abstract: The present invention provides a method of preparing an MOF-coated monocrystal ternary positive electrode material. Firstly, a solution A of nickel, cobalt and manganese metal salts, an ammonia complexing agent solution and a caustic soda liquid are added to a reactor for reaction to obtain a precursor core; then, an organic carboxylate is dissolved in an amount of an organic solvent to obtain a solution B; the solution B and a manganese metal salt solution with a given concentration are added to the reactor and aged to obtain an MOF-coated core-shell structure precursor; the core-shell structure precursor is pre-sintered at a low temperature to obtain a nickel-cobalt-manganese oxide with monocrystal structure; the nickel-cobalt-manganese oxide with monocrystal structure is uniformly mixed with LiOH.H2O in a mortar and then calcined at a high temperature to obtain an MOF-coated monocrystal ternary positive electrode material.