High-density graphene and preparation method thereof

Abstract

The invention discloses high-density graphene and a preparation method thereof, and relates to the field of preparation of energy material graphene. The preparation method comprises the following steps: preparing a graphene film from a graphene solution, reducing the graphene film, and finally crushing the reduced graphene film in a crusher to obtain the high-density graphene. The preparation method for the graphene film comprises a suction filtration method and a scrap-coating method, and the reduction method comprises thermal reduction and chemical reagent reduction. The dense graphene filmis crushed in the crusher, the high-density structural characteristic of graphene can be maintained, the integrity of the graphene film also can be broken, and the ion transmission path can be shortened, so that the prepared high-density graphene has high density, high volume capacity, excellent rate performance and long cycle life in the field of electrochemical energy storage. Compared with theprior art, the preparation method provided by the invention is simple and low in cost, and can be applied to large-scale industrialized production.

Description

technical field [0001] The invention relates to the field of preparation of energy material graphene, in particular to a high-density graphene and a preparation method thereof. Background technique [0002] As people's demand for portable and mobile electronic devices is increasing, the volumetric capacity of energy storage devices becomes particularly important. As one of the important components, the electrode material directly determines the electrochemical performance of the device. Electrode materials represented by graphene are research hotspots in the field of energy storage. Graphene has the advantages of stable structure, good electrical conductivity, and large specific surface area. However, it is difficult for these graphene materials to meet the requirements of high density and high quality specific capacity at the same time. Therefore, the excellent performance of many materials has not been well reflected in the device, which greatly reduces its practicality...

AI Technical Summary

Problems solved by technology

Although the above research can increase the specific surface area of ​​graphene materials to a certain extent, it also increases the pores between graphene materials and reduces the packing density of graphene materials.

[0005] In summary, although some research methods can effectively increase the density of graphene materials, it is difficult to overcome the problem of close packing between graphene sheets, which seriously hinders the transport of electrolyte ions, or some researched graphene sheets The pores between them are too large and the packing is not tight, resulting in low density and low volume capacity

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