Surface coating modification method for ternary positive electrode material of lithium ion battery

Abstract

The invention discloses a surface coating modification method for a ternary positive electrode material of a lithium ion battery, and belongs to the field of positive electrode materials of lithium ion batteries. The method comprises the following steps: sequentially loading an aluminum source and an oxygen source onto the surface of a ternary positive electrode plate of the lithium ion battery by using carrier gas by utilizing an atomic deposition system: adsorbing a layer of aluminum source on the surface of the ternary positive electrode plate of the lithium ion battery, and then carrying out combination reaction on the oxygen source and the adsorbed layer of aluminum source to generate an aluminum oxide layer; repeating the cycle number of the aluminum oxide layer, namely depositing an aluminum oxide film on the surface of the ternary positive electrode plate of the lithium ion battery, so as to realize coating modification on the surface of the ternary positive electrode material of the lithium ion battery. The surface coating modification method for the ternary positive electrode material of the lithium ion battery is short in preparation period, safe and simple in method, low in energy consumption, simple in required equipment and suitable for modification of various ternary positive electrode materials.

Description

technical field [0001] The invention belongs to the field of positive electrode materials of lithium ion batteries, and in particular relates to a surface coating modification method of ternary positive electrode materials of lithium ion batteries. Background technique [0002] With the massive consumption of fossil fuels, human beings are facing unprecedented energy crisis and environmental pollution. Lithium-ion batteries are widely used in all aspects of human life due to their high energy density, long cycle life, and environmental protection. However, the specific capacity of the cathode material of lithium-ion batteries is low, and the performance decays quickly, which seriously restricts the development of lithium-ion batteries. Ternary cathode materials, especially high-nickel ternary cathode materials, due to the synergistic effect of nickel, cobalt, and manganese, have higher capacity, better cycle performance, and moderate price than other cathode materials. Den...

AI Technical Summary

Problems solved by technology

However, the lithium-ion battery cathode material has low specific capacity and fast performance decay, which seriously restricts the development of lithium-ion batteries.

Ternary cathode materials, especially high-nickel ternary cathode materials, due to the synergistic effect of nickel, cobalt, and manganese, have higher capacity, better cycle performance, and moderate price than other cathode materials. Density is an important material, but there are still many problems in the ternary cathode material: for example, it is easy to have side reactions with the electrolyte, resulting in the reconstruction of the surface structure, the dissolution of the transition metal, and the generation of microcracks, and the microcracks will expose more More reaction sites, further leading to the generation of phase transition and the expansion of microcracks

[0003] In response to the above problems, scholars have explored various methods for modification. Among them, coating the surface of ternary cathode material particles is one of the most effective methods, but there are complex preparation methods, expensive raw materials, environmental pollution by by-products, and performance improvement. limited

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