Preparation method of lithium cobalt oxide-coated high-nickel ternary material

Abstract

The invention provides a preparation method of a lithium cobalt oxide-coated high-nickel ternary material. The method comprises the following steps of: S1: taking and uniformly mixing a precursor of ahigh-nickel ternary material with an alkaline solution, and putting the mixture in a vacuum drying oven for drying to obtain mixed powder; S2: putting the dried mixed powder into an ozone oxidation reaction device, introducing ozone gases into the ozone oxidation reaction device, and performing stirring and oxidation; S3: washing the precursor in the step S2 by using hot deionized water, and drying the precursor after washing; and S4: uniformly mixing the dried precursor in the step S3 and a lithium source, and putting the mixture into a high-temperature furnace, performing temperature rise in an oxygen atmosphere in a sintering temperature from the room temperature to a sintering temperature, performing heat preservation, and performing natural cooling after heat preservation to obtain alithium cobalt oxide-coated high-nickel ternary material. The method employs the ozone oxidation method to perform oxidation for the Co2+ at the surface of the precursor to allow the surface of the precursor to generate structural recombination to generate a layer of CoOOH, and the precursor with the CoOOH at the surface is mixed with the lithium source for high-temperature calcinations to obtaina CoOOH-coated high-nickel ternary material.

Description

technical field [0001] The invention belongs to the technical field of positive electrode material preparation, and in particular relates to a preparation method of a high-nickel ternary material coated with lithium cobaltate. Background technique [0002] As a new type of green power source, lithium-ion batteries have been widely used in electric vehicles, energy storage power stations and electric tools due to their high voltage, high specific energy, green safety and environmental protection. In recent years, the market has increasingly higher requirements for the capacity and energy density of lithium-ion batteries. The early lithium iron phosphate batteries have been unable to meet market requirements. Under this background, major battery manufacturers have turned their attention to 523, 622 and High-nickel ternary batteries represented by 811, etc. Therefore, high-nickel ternary materials have attracted more and more attention, and have become a research hotspot in the...

AI Technical Summary

Problems solved by technology

[0003] At present, the main synthesis method of ternary materials is the solid-phase method, that is, the ternary precursor Ni prepared by co-precipitation x co y m 1-x-y (OH) 2 Mechanically mixed with lithium source and then sintered at high temperature. In the later stage of synthesis, the ternary material is exposed to the air, which will absorb moisture and carbon dioxide in the air, resulting in the formation of residual alkali on the surface of the material, and, with the increase of nickel content, the ternary material The water absorption continues to increase, and the residual alkali content on the surface continues to increase, and more residual alkali is not conducive to the processing performance of ternary materials, but also deteriorates the cycle and storage performance of ternary materials

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