Lithium sulphur battery anode material and preparation method thereof

Abstract

The invention relates to a lithium sulphur battery anode material and a preparation method thereof. The lithium sulphur battery anode material is a reduction oxidized graphene aerogel nested sulphur nano particle composite material with a three-dimensional net-shaped structure. The preparation method of the lithium sulphur battery anode material comprises the steps that, gel is formed by online reducing a oxidized graphene gel and sulphur gel mixture, the gel is frozen and dried, and the reduction oxidized graphene aerogel nested sulphur nano particle composite material with the three-dimensional net-shaped structure is obtained. The preparation method specifically comprises the steps that oxidized graphene serves as an initial raw material, mixed gel of oxidized graphene and sulphur is prepared, reduction oxidized graphene gel is prepared by adopting an online reduction method at the room temperature to wrap the sulphur nano particle composite material, the internally wrapped solventis removed through freeze drying, and the reduction oxidized graphene aerogel nested sulphur nano particle composite material is obtained. The lithium suplhur battery anode material can effectively prevent dissolution and inhibition shuttle effects of polysulfide, and can enhance the charging and discharging stability of the lithium sulphur battery.

Description

technical field [0001] The invention belongs to the technical field of new energy, and relates to a lithium-sulfur battery positive electrode material, in particular to a reduced graphene oxide airgel-embedded lithium-sulfur battery positive electrode material and a preparation method thereof. Background technique [0002] With the rapid development of new energy technologies, especially with the potential market demand in the field of intelligent communication and electric vehicles, it is imminent to develop electrochemical energy storage systems with low cost, high energy density, long life and environmental friendliness. With the existing lithium-ion battery technology, it is difficult for the current commercialized lithium-ion battery to break through 300 Wh / kg, which cannot meet the needs of the new energy industry for high-performance batteries. [0003] In the new electrochemical energy storage system, the theoretical specific energy of the lithium-sulfur battery with...

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Problems solved by technology

[0004] The existing technologies for preparing lithium-sulfur cathode materials mostly use conductive materials such as carbon, conductive polymers, and conductive oxides (TiO 2 etc.) etc. to prepare sulfur / conductor composites by means of doping, compounding or coating. This method of preparing sulfur composites usually has the following disadvantages: (1) Most of these methods first prepare hollow, porous Conductive material, and then sulfur is embedded in the conductive material through physical sublimation, so that sulfur cannot be completely confined in a fixed space, and some residual sulfur still stays outside the conductive material, and this part of sulfur is formed during charging and discharging The polysulfides in the electrolyte will still be dissolved in the electrolyte, resulting in a shuttle effect, reducing the coulombic efficiency and cycle efficiency of the lithium-sulfur battery; (2) The size of the hollow or hole in the initially prepared hollow or porous material directly affects the electron and ion flow rate. (3) The process of preparing composite electrode materials is relatively cumbersome, the cost is relatively high, and it is not easy to produce on a large scale

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