Lithium phosphate coated lithium ion battery high-nickel positive electrode material and preparation method thereof

Abstract

The invention belongs to the technical field of preparation of a lithium ion battery high-nickel positive electrode material, and particularly provides a lithium phosphate coated lithium ion battery high-nickel positive electrode material and a preparation method thereof. The material and the preparation method are used for overcoming the defects of poor processing performance, harsh requirements on use environment, poor cycling stability, low first-circle coulombic efficiency and sharp reduction of high-temperature performance in the prior art. Lithium dihydrogen phosphate is taken as a coating raw material, and a fast ion conductor lithium phosphate coating layer is generated through in-situ reaction of lithium dihydrogen phosphate and residual alkali (LiOH and Li2CO3) on the surface of a parent material, so that lithium salt residues on the surface of the parent material are greatly reduced, the processing performance is improved, the requirement on a use environment is reduced, the ionic conductivity of the positive electrode material is increased, the number of lithium ions of the positive electrode material is increased, and phase change and interface side reaction are effectively inhibited, therefore, the lithium phosphate coated lithium ion battery high-nickel positive electrode material has excellent cycling stability and specific discharge capacity, and especially can maintain relatively good electrochemical performance at high temperature.

Description

technical field [0001] The invention belongs to the technical field of preparation of high-nickel positive electrode materials for lithium-ion batteries, relates to coating modification of high-nickel (molar ratio Ni≥80%) positive-electrode materials for lithium-ion batteries, and specifically provides a high-nickel lithium-ion battery coated with lithium phosphate Cathode material and preparation method thereof. Background technique [0002] With the rapid development of modernization and industrialization, the demand for energy is increasing, and energy shortage and environmental problems are becoming more and more obvious. It is imminent to develop and utilize clean and environmentally friendly energy. It is very important to implement sustainable development strategies and develop new environmentally friendly green power sources. The most typical lithium-ion batteries have been widely developed and utilized because of their high energy density, long cycle life and enviro...

AI Technical Summary

Problems solved by technology

[0004] The purpose of the present invention is to provide a lithium phosphate-coated lithium-ion battery for the disadvantages of poor processing performance, harsh requirements on the use environment, poor cycle stability, low first-cycle Coulombic efficiency, and sharp drop in high-temperature performance of lithium-ion battery high-nickel cathode materials. Battery high-nickel cathode material and preparation method thereof

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