Lithium battery positive electrode material and conductive additive

Abstract

The invention provides a lithium battery positive electrode material containing a fluorine-containing alkyl compound additive and / or a weak acid additive. The fluorine-containing alkyl compound additive has a very high chemical stability and maintains a good surface activity in a solvent. A small amount of the fluorine-containing alkyl compound additive is added to a positive electrode material inorder to reduce the surface tension of a solvent-based system, so the wetting property, the dispersing property, the leveling property and other surface properties of the positive electrode materialare enhanced, the diffusion of lithium is facilitated, and the rate performance is improved. The addition of the weak acid additive can reduce the amount of residual alkalis on the surface of the positive electrode material. Additionally, the fluorine-containing alkyl compound additive has hydrophobic properties, so the waterproof property of the positive electrode material is improved, the requirements for the humidity of the storage and use environment of the positive electrode material are reduced, and the cost is saved.

Description

technical field [0001] The invention relates to the field of lithium batteries, in particular, the invention relates to a lithium battery cathode material and a conductive additive. Background technique [0002] Lithium batteries have the advantages of high energy density, high working voltage, and no memory effect in cycles. They are currently ideal chemical power sources and have been widely used in various portable electronic products and electric vehicles. Because the characteristics of lithium batteries are essentially determined by the performance of the electrode materials used in batteries, electrode materials, especially positive electrode materials, are the most important part in the development and research of lithium batteries. [0003] The materials used to make the positive electrode of lithium batteries are mainly LiCoO 2 , LiNiO 2 , LiMn 2 o 4 , nickel-cobalt-manganese ternary system and LiFePO 4 , where LiCoO 2 It has been commercialized and is current...

AI Technical Summary

Problems solved by technology

[0004] However, the currently commonly used positive electrode materials have high residual alkali on the surface and are sensitive to moisture, so the requirements for their storage environment are strict, especially for high-nickel materials.

At the same time, the dispersion of most cathode materials is not very good during slurry mixing, resulting in the inability to fully exert their electrochemical performance.

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