Method for preparing lithium-rich composite positive electrode material, positive electrode and battery

Abstract

The invention discloses a method for preparing a lithium-rich composite positive electrode material, a positive electrode and a battery. Specifically, the present invention proposes a method for preparing a lithium-rich composite positive electrode material, comprising: adding the cladding layer material into water and stirring to form a first mixture; adding a lithium-rich material to the first mixture, stirring and reacting, forming a second mixture; filtering, drying, and first calcining the second mixture to obtain a lithium-rich material whose surface is covered with the cladding layer material, to obtain a lithium-rich composite positive electrode material, wherein the cladding layer material is dissolved in water , and the coating material contains lithium ions and fluorine ions. Therefore, using this method, the surface of the lithium-rich material can be easily coated with a coating layer material containing lithium ions and fluorine ions, and when the obtained lithium-rich composite positive electrode material is used as an electrode, the negative impact of the positive electrode and the electrolyte can be reduced. reaction, the electrode structure is stable, and has a high discharge specific capacity, as well as good rate performance and cycle performance.

Description

technical field [0001] The invention relates to the technical field of batteries, in particular to a method for preparing a lithium-rich composite positive electrode material, a positive electrode, and a battery. Background technique [0002] At present, lithium-ion batteries are widely used in cameras, mobile phones, notebook computers, electric vehicles and other equipment due to their advantages such as stable voltage, high capacity, high energy density, long cycle life, and environmental friendliness. The cathode material of lithium-ion batteries is the key factor determining its performance. Among them, lithium-rich materials are a new high-capacity cathode material in recent years. They have a solid solution structure and have a high charge-discharge specific capacity. There is a large irreversible capacity loss during the charge and discharge process, and there is voltage decay during the cycle, and the rate performance and cycle performance are poor. These problems h...

AI Technical Summary

Problems solved by technology

The cathode material of lithium-ion batteries is the key factor determining its performance. Among them, lithium-rich materials are a new high-capacity cathode material in recent years. They have a solid solution structure and have a high charge-discharge specific capacity. There is a large irreversible capacity loss during the charge and discharge process, and there is voltage decay during the cycle, and the rate performance and cycle performance are poor. These problems hinder the large-scale application of lithium-rich materials.

[0003] Therefore, the current method of preparing lithium-rich composite cathode materials, cathodes, and batteries still need to be improved.

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