Preparation method of anode material of lithium ion power battery

Abstract

The invention relates to an anode material of a battery, mainly relates to a preparation method of an anode material of a lithium ion power battery and belongs to the field of lithium ion power battery manufacturing. The preparation method sequentially comprises the following steps: (1) mixing thermosetting resin and an organic solvent, then adding graphite raw material, subsequently adding a curing agent, then removing the organic solvent contained in the mixture, and curing; (2) dispersing the thermosetting resin-doped mixture in a dispersing agent for 1-2 hours in a way of mixing and ball milling, and then drying; (3) adding a compound modifier into the dried and cured mixture, and heating to obtain a mixture subjected to compound modification; and (4) vapor depositing a silicon-carbon organic matter precursor on the mixture subjected to compound modification at the temperature of 500-1500 DEG C under the pressure of 1-2MPa, thus obtaining a carbon anode material with the surface coated with carbon and silicon, namely the anode material of the lithium ion power battery, which has the advantage of the improved electrical performance.

Description

technical field [0001] The invention relates to a battery negative electrode material, mainly relates to a preparation method of a lithium ion power battery negative electrode material, and belongs to the field of lithium battery production. Background technique [0002] Lithium-ion batteries have the advantages of high working voltage, large specific energy, and good safety performance, and are widely used in mobile communications, notebook computers and other fields. Especially with the wide application of electric vehicles in the future, higher requirements are put forward for lithium-ion batteries. . Natural graphite materials as negative electrode materials have the advantages of abundant reserves, high specific capacity, low voltage platform, and very strong cost performance, but there are serious defects in direct use, such as low initial discharge efficiency, poor cycle performance, and electrolysis. The shortcomings of high liquid selectivity limit the application ...

AI Technical Summary

Problems solved by technology

The key to this method is to form a complete coating on the outside of the graphite, otherwise it will not be able to prevent the contact between the electrolyte and the graphite. Generally, a layer of resin carbon is coated on the surface of the natural microcrystalline graphite particles to form a core-shell structure. The inside is natural microcrystalline graphite, and the outside is a 1-2 μm phenolic resin pyrolytic carbon layer. Coating treatment can reduce the first irreversible capacity of natural microcrystalline graphite, but only coating the resin hard carbon precursor will make it incompatible with graphite materials. In addition, due to the low degree of graphitization of the hard carbon precursor, it will affect the first charge and discharge performance of the material and its specific surface area is large, which is not conducive to the manufacturing process of the battery. Therefore, the graphite material coated with hard carbon needs to be processed. Processing to make its cycle and rate performance more superior

The Chinese patent with the publication number CN101162775A (2008-04-16) adopts the method of mixing resin and pitch to coat the graphite material. This method also has some deficiencies in practical application, resulting in a low carbonization rate of the resin, which affects the final first-time efficiency of the material.

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