Impact of C-S-TiO₂ Composite Material Coated by Graphene on the Conductive Properties of Sulfur Cathode Material

摘要

The way to solve the sulfur conductive problem is the key to improve the performance of lithiumsulfur battery. Nano oxides can not only improve sulfur electrode porosity, but also adsorb moresulphur, in addition play a catalytic role to oxidation reduction reaction of cells, the graphene has aunique two-dimensional structure and excellent physical and chemical properties, very suitable forcoating composite containing sulfur materials. This paper was studied on electrical properties of sulfurcathode materials on lithium sulfur batteries, and the influence on sulfur electrochemical performanceof C/S composite material, C-S-TiO2 composite material, C-S-TiO2 composite material coated bygrapheme. Three composite materials were characterized by used XRD, SEM. The results showed thatthe specific capacity of C-S-TiO2 composite material coated by grapheme reach to 1366 mAh/g, C/Scomposite material was 400 mAh/g, while the C-S-TiO2 composite material, the specific capacity up to966mAh/g.After 20 cycles of charge and discharge, C-S-TiO2 composite material coated by grapheneretention rate was 78.9%, while C/S composite material was lower to 62.6%.