Preparation method of graphene material and application of graphene material in preparation of lithium ion battery

Abstract

The invention provides a preparation method of a graphene material and the application of the graphene material in preparation of a lithium ion battery. According to the preparation method, simple, convenient and easy-to-obtain graphite powder is used as a raw material, and the graphite powder is oxidized by adopting a plasma oxidation-chemical oxidation combined technology to prepare a graphene oxide precursor; then graphene oxide is prepared from the graphene oxide precursor through a plasma oxidation technology; and finally, the graphene material is prepared by adopting a plasma reduction technology. Compared with a single chemical oxidation process, the preparation method disclosed by the invention has the advantages that consumed time is shorter, large-scale production can be realized, functional groups can be added for modification in the preparation process, no explosion risk exists in the preparation process, and environmental pollution is very small; the edge of the prepared graphene is oxidized to generate carbonyl groups, hydroxyl groups and other hydrophilic groups, so the solubility of the graphene in an aqueous solution is increased; compared with the original graphite oxide material, the prepared graphene material has the advantages that interlayer spacing is obviously increased, and stripping effect is obvious; and when the graphene material is used for preparing a lithium ion battery negative electrode material, the specific capacity of the lithium ion battery negative electrode material in actual use is close to a theoretical value during initial chargingand discharging.

Description

technical field [0001] The invention relates to the field of graphene materials and the field of using graphene to prepare negative electrode materials for lithium ion batteries. Background technique [0002] At present, lithium-ion battery anode materials are a key factor restricting the development of lithium-ion batteries, among which graphite is currently the most commercialized anode material, which is environmentally friendly, low cost, high specific capacity, good cycle performance, long life, Low chemical potential and other characteristics. However, graphite still has some problems that need to be solved, such as: poor compatibility with electrolyte solution; poor high-rate charge and discharge performance; solvent molecules will enter the graphite layer during the charging process and cause the graphite layer to peel off. , resulting in reduced battery cycle performance, which limits the mature mass production of lithium-ion batteries based on the current technolo...

AI Technical Summary

Problems solved by technology

However, KClO 3 It is highly explosive when mixed with combustibles, and KClO 3 Toxic and flammable gas ClO will be produced in concentrated sulfuric acid solution with graphene oxide 2 , there is a great security risk; KMnO 4 Easily converted to Mn in acidic environment 2 o 7 , there is a danger of explosion when it is higher than 55 ° C, and KMnO 4 The use of manganese ions will produce a lot of manganese ions, which is a great threat to human health and plants in the ecosystem

Therefore, both methods have considerable risks.

Simultaneously, these two kinds of methods all need longer reaction time and reaction temperature, need to improve

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