Carbon-based composite material as well as preparation method and application thereof

Abstract

The invention provides a carbon-based composite material and a preparation method and application thereof, and belongs to the technical field of electrode materials. A flocculent carbon source precursor is prepared on the basis of graphene oxide colloid and a halogen-containing high-molecular carbon source suspension through vacuum freeze drying, then the flocculent carbon source precursor is subjected to reduction heat treatment, and the carbon-based composite material is obtained. The method is easy to operate, low in production cost and beneficial to commercial production, and the prepared carbon-based composite material can be directly used as an electrode material. By regulating and controlling the mass ratio of the halogen-containing polymer carbon source to the graphene oxide, the carbon-based composite material has a special microstructure of two-dimensional film coated carbon microspheres, and has higher reversible capacity and good rate capability when being used as an electrode material.

Description

technical field [0001] The invention relates to the technical field of electrode materials, in particular to a carbon-based composite material and a preparation method and application thereof. Background technique [0002] Carbon-based anode materials have the advantages of high energy density (such as graphite specific capacity of 372mAh / g), environmental friendliness, low price, and simple preparation. They are currently the mainstream anode materials for lithium-ion batteries used in mobile phones, notebook computers and electric vehicles , Since Japan's Sony Corporation developed the first commercial carbon anode battery in 1991, the types of commercial anode materials have not changed significantly. However, carbon-based anodes cannot guarantee battery capacity fading and safety issues caused by high-power output conditions, even the most common graphite anodes, considering their low self-reaction potential (about 0.1V vs. Li / Li + ), close to the reaction potential of ...

AI Technical Summary

Problems solved by technology

In the prior art, the sol is usually prepared by dispersing the high molecular polymer in an organic solvent, and then directly mixed with the particles to be coated and then heat-treated. 3 Hybridization forms cross-linking, which is not conducive to the parallel or regular growth of carbon materials along the direction of the basal plane. The obtained carbon materials are in a continuous and irregular state, forming a carbon block as a whole, and the uniformity of coating thickness is extremely poor.

When a hard template (such as MgO, ZnO, CaO, etc.) is introduced, the carbon atoms in the polymer carbon source can be induced to pass through sp 2 Hybridization forms regular-shaped composite nanostructures to obtain porous carbon materials. Usually, the pore structure of carbon materials can be adjusted by adjusting the particle size of the hard template. However, the porous carbon materials prepared by the above method have a small packing density and volume capacity remains to be Improvement, and this method requires a large amount of acid or alkali to wash the sample to obtain pure carbon products, the operation is complicated, the cost is high, and it is not conducive to commercial production

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