Method for preparing anode material of lithium ion battery by high-temperature reaction of expansible graphite and zinc powder

Abstract

The invention relates to a method for preparing an anode material of a lithium ion battery by high-temperature reaction of expansible graphite and zinc powder. The method comprises the following steps of using the expansible graphite and the zinc powder as raw materials; carrying out high-temperature reaction of the expansible graphite and the zinc powder in a temperature condition of the zinc powder serving as an air phase; and preparing to obtain a composite electrode material of the expanded graphite and zinc oxide, wherein a vacuum environment is controlled or an inert gas is introduced during the reaction process. The method disclosed by the invention is a one-step reaction method, the problems of complicated step and long time consumption existing in the prior art by using the expanded graphite and a zinc source for wet synthesis are solved, and the preparation process is simplified; not only the zinc oxide is deposited on the surface of the expanded graphite and among layers, but also the oxidation-reduction reactions are included; and a part of oxygen in the expanded graphite is reduced by zinc, the oxidation degree of the expanded graphite is further reduced, meanwhile, the generated zinc oxide is taken as the electrode material, and the specific capacity of the electrode material is also improved.

Description

technical field [0001] The invention relates to the field of preparation of lithium-ion battery negative electrode materials, in particular to a method for preparing lithium-ion battery negative electrode materials by high-temperature reaction of expandable graphite and zinc powder. Background technique [0002] Lithium-ion batteries have been more and more used in electric vehicles, mobile phones and other tools, and have become an important energy storage tool in people's lives. People's requirements for lithium-ion batteries are also getting higher and higher. The key to improving the performance of lithium-ion batteries lies in Improve and invent new electrode materials. [0003] Graphite is an abundant natural resource and is commonly used as an electrode material for lithium-ion batteries. Graphite is a layered structure, carbon atoms on the same layer are connected by covalent bonds, and layers are connected by π bonds. The bonding between layers is relatively weak....

AI Technical Summary

Problems solved by technology

[0004] Zinc oxide is a transition metal oxide with a theoretical specific capacity as high as 978mAh / g. It is a widely researched battery anode material. However, the poor conductivity of zinc oxide itself makes it difficult to give full play to its high specific capacity, so it is often associated with electrical conductivity. Preparation of electrode materials by compounding materials with good properties

[0005] The prior art discloses some methods (such as CN103215628A, CN102580715A, etc.) for wet synthesis of expanded graphite and zinc oxide composite materials utilizing expanded graphite and zinc source, but the prepared material has to go through multiple washing and drying processes, and the steps are more complicated; In addition, based on the consideration of electrode materials, there is also a method of using graphene instead of expanded graphite to synthesize the composite material of the two by wet method, but the preparation process of graphene is complicated, the price is high, and it is not suitable for large-scale applications; further, the prior art prepares expanded graphite. In the method of graphite and zinc oxide composite materials, the expanded graphite used still has the problems of low specific capacity of the electrode material and a slightly higher degree of oxidation.

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