Lithium ion battery anode and preparation method thereof

Abstract

The invention belongs to the field of lithium ion batteries, and particularly discloses a lithium ion battery positive electrode and a preparation method thereof. The preparation method comprises thefollowing steps that S1, to-be-modified powder is put into a reaction cavity, the reaction cavity is made to be in a vacuum state, then the reaction cavity is rotated and heated, and the to-be-modified powder is made to be evenly distributed in the reaction cavity; S2, a precursor and purging gas are alternately introduced into the reaction cavity, and the precursor reacts with the to-be-modifiedpowder, so that a layer of oxide film is formed on the surface of the to-be-modified powder; S3, S2 is repeated for multiple times to form multiple layers of oxide films on the surface of the to-be-modified powder so as to finish powder modification; and S4, the modified powder is blended into slurry, a metal sheet is coated with the slurry, and vacuum drying is carried out to complete the preparation of the lithium ion battery positive electrode. By depositing the oxide film on the surface of the lithium ion battery positive electrode material powder, the stability of the lithium ion batterypositive electrode in the charging and discharging processes is improved, and the service life of the lithium ion battery is prolonged.

Description

technical field [0001] The invention belongs to the field of lithium ion batteries, and more specifically relates to a positive electrode of a lithium ion battery and a preparation method thereof. Background technique [0002] Lithium-ion batteries are widely used in military, new energy vehicles, small electrical appliances and other fields due to their advantages such as wide operating temperature range, small size, high energy density, and long life. However, with the gradual increase in the energy density of lithium-ion batteries, serious stability problems have been brought about. The main sources of stability problems include structural changes in the positive and negative electrode materials under long-term overcharge and overdischarge conditions, resulting in Lithium-ion batteries are thermally runaway, so it is of great significance to improve the stability of lithium-ion battery cathode materials through precise coating. [0003] Traditional methods to improve the...

AI Technical Summary

Problems solved by technology

However, with the gradual increase in the energy density of lithium-ion batteries, serious stability problems have been brought about. The main sources of stability problems include the structural changes of the positive and negative electrode materials under long-term overcharge and overdischarge conditions, resulting in Lithium-ion batteries are thermally runaway, so it is of great significance to improve the stability of lithium-ion battery cathode materials through precise coating

[0003] Traditional methods to improve the stability of lithium-ion batteries include surface coating, doping or composite materials, surface modification, and construction of special structures. However, most of them are based on the modification of battery materials, and the efficiency is low and the effect is unstable. The material has stable performance when it is prepared into an electrode by co-precipitation, sol-gel, solid-phase method, hydrothermal method and other processes

[0004] Currently, there will be Al 2 o 3 , ZnO, AZO and other metal compounds coated on the ternary material (a commonly used lithium-ion battery cathode material), but because the lithium battery cathode material is too heavy compared to other powders, it is impossible to make the powder material It is completely dispersed in the cavity, and more energy needs to be provided to overcome the specific surface energy of the powder and reduce the size of the agglomeration, so that all powder materials cannot be completely modified, and ultimately the performance of the lithium battery cannot meet the expected requirements.

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