A kind of preparation method of lithium-sulfur battery cathode material

Abstract

The invention relates to an electrode composed of active materials, in particular to a lithium-sulfur battery anode material preparation method. Graphene is structurally modified for preparing graphene hollow spheres by a template method and spray drying technology combined pore forming technology, and then ball milling and hot-melt sulfur doping processes are adopted for preparing a graphene hollow sphere-sulfur combined three-dimensional lithium-sulfur battery anode material. Defects of low effective sulfur loading quantity, evident polysulfide 'aero effect', evident lithium-sulfur battery volume expansion effect and battery electrochemical performance instability of lithium-sulfur battery anode materials prepared in the prior art are overcome.

Description

technical field The technical solution of the invention relates to an electrode composed of active materials, in particular to a preparation method of a cathode material for a lithium-sulfur battery. Background technique Lithium-ion battery is a new type of battery with environmental protection and high specific energy. Although the development of lithium-ion batteries is very mature, and its specific energy is very close to the theoretical specific energy of its corresponding materials (graphite anode is 300mAh / g), it still cannot satisfy people's growing demand for new batteries with environmentally friendly and high specific energy. The development of next-generation lithium secondary battery cathode materials with high energy density, environmental protection and low cost has become an urgent problem to be solved. As the most promising lithium secondary battery, the theoretical specific energy of the new lithium-sulfur battery is 2600Wh / kg, which is 5 times the theoreti...

AI Technical Summary

Problems solved by technology

Although the above-mentioned existing technologies of graphene-sulfur composite cathode materials have improved the performance of lithium-sulfur batteries to a certain extent, they still have common defects: the effective loading of sulfur in the cathode material is low, and the "shuttle effect" of polysulfides Obviously, the volume expansion effect of lithium-sulfur batteries is significant, the electrochemical performance of the batteries is unstable, the material yield is low, and the feasibility of industrial production is poor

Although this prior art has improved the structural properties of graphene to a certain extent, there are still obvious defects: the materials involved in its preparation process are toxic and expensive, and cannot meet the requirements of environmental protection and industrial production. The graphene prepared by calcination has obvious edge defects, which cannot be applied to the preparation of cathode materials for lithium-sulfur batteries

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