Germanium-graphene composite cathode material for lithium ion battery and preparation method thereof

Abstract

The invention discloses a germanium-graphene composite cathode material for a lithium ion battery and a preparation method of the germanium-graphene composite cathode material. The composite cathode material is prepared from germanium particles and grapheme through compounding, wherein the nano germanium particles are uniformly distributed in a grapheme sheet layer to form a grapheme network cladded three-dimensional net structure. The preparation method comprises the following steps: (1) stirring and dispersing; (2) carrying out microwave hydrothermal; and (3) washing, drying and collecting. According to the germanium-graphene composite cathode material for the lithium ion battery and the preparation method of the germanium-graphene composite cathode material, germanium and germanium dioxide are re-crystallized and grow on the graphene in situ, the bonding strength of the germanium and the grapheme is higher than that of germanium-graphene composite material obtained through mixing simply, the electrical conductivity of the grapheme network is fully exerted, and the volume effect of the germanium is effectively inhibited. The germanium-graphene composite cathode material for the lithium ion battery has the characteristics of high capacity, high magnification and excellent cycling stability, the preparation process adopts simple and effective microwave hydrothermal reaction, the process is simple, the energy consumption is low, the yield is high, no pollution is caused, the germanium-graphene composite cathode material can be promoted and applied conveniently and is suitable for large-scale production.

Description

technical field

[0001] The invention relates to the technology in the field of battery negative electrode materials, in particular to a lithium-ion battery germanium-graphene composite negative electrode material and a preparation method thereof. Background technique

[0002] At present, a large number of commercial lithium-ion batteries use graphite-based carbon materials as negative electrode materials. Due to the low mass specific capacity of graphite-based carbon materials (the theoretical value is 372mAh / g, the actual capacity is 330-360mAh / g) and relatively low Poor high-rate charge and discharge performance limits the improvement of lithium-ion battery capacity. In order to meet the future demand for high-capacity and long-life lithium-ion batteries for civil, industrial or national defense, researchers are constantly exploring other high-capacity carbon alternative materials, such as metals and alloy materials. Among them, the theoretical specific capacity of metal ...

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