Graphite anode material with low-magnetic substance for lithium battery and preparation method of graphite anode material

Abstract

The graphite anode material with the low-magnetic substance for the lithium battery comprises 90-110 parts of a graphite main body material, 10-50 parts of a carbonization material, 5-10 parts of an adhesive, 1-15 parts of a surfactant and 1-500 parts of water, and the carbonization material is prepared from at least one of needle coke and pitch coke through high-temperature reaction and heat preservation magnetization. The invention also provides a preparation method. The preparation method comprises the following steps: (1) putting the carbonized material into a shearing mixer with the vibration frequency of 10-15Hz, and stirring; (2) adding an adhesive, and mixing at the vibration frequency of 15-25Hz; (3) mixing the materials at the vibration frequency of 10-15Hz; (4) adding a surfactant and water, performing high-frequency stirring until the viscosity reaches the standard, adding an adhesive, and performing low-frequency stirring and uniform mixing; and (5) coating a copper foil, feeding into a drying box, and drying to obtain the graphite negative plate for the lithium battery. The carbonization material makes up the defects of low tap density of a graphite main body material and instability of a negative electrode material caused by lamination of an intermediate phase structure, and reduces the accident occurrence probability in cooperation with a modified drying box.

Description

technical field [0001] The invention belongs to the technical field of graphite material preparation, and in particular relates to a low-magnetic graphite negative electrode material for lithium batteries and a preparation method thereof. Background technique [0002] A lithium-ion battery mainly includes a positive electrode, a negative electrode, an electrolyte that can conduct lithium ions, and a separator that separates the positive and negative electrodes. Among them, lithium-ion battery negative electrode materials are divided into the following categories: carbon material negative electrodes (including graphite carbon materials, non-graphite carbon materials, doped carbon materials, coated carbon materials), non-carbon negative electrodes (including alloy negative electrodes and transition metal oxide anode). In recent years, lithium-ion batteries have been widely used in various portable electronic devices, and gradually applied to emerging fields such as electric v...

AI Technical Summary

Problems solved by technology

However, for high-power graphite anode materials, due to the low tap density of the material itself, relatively large specific surface area, and more functional groups, when the direct wet mixing process is used, it will cause the components in the slurry to be difficult to obtain. Uniform mixing, even agglomeration and stratification. In addition, the long-term dispersion process can easily lead to side reactions between the functional groups on the graphite and other substances, and ultimately it is impossible to obtain a uniform and stable negative electrode slurry

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