剑麻生物质多孔碳/硫复合电极材料的制备及性能

Preparation and Properties of Porous Carbon from Sisal Hemp/Sulfur Composite Electrode Materials

为解决锂硫(Li-S)电池在实际应用中S和Li_(2)S_(2)/Li_(2)S不导电、体积膨胀和多硫化物的“穿梭效应”等问题,本次试验采用化学活化法制备剑麻基生物碳(AC),熔融扩散法制备碳/硫复合正极材料(ACS),因多壁碳纳米管(MWCNTs)具有独特的三维结构,可以抑制多硫化物的穿梭效应,将其作为隔膜涂层(YTC)。试验结果表明,在0.10 C倍率下,YTC电池的初始放电容量为974.3 mAh·g^(-1),循环200圈后容量保持在622 mAh·g^(-1)。进一步说明在隔膜上涂覆MWCNTs与正极材料结合,可提高材料导电性和抑制多硫化物的穿梭效应,表现出良好的循环性能和库伦效率。

Sisal-based biological carbon(AC)was prepared with chemical activation method and carbon/sulfur composite cathode material(ACS)was prepared with melting diffusion method to solve the problems of non-conductivity and volume expansion of S and Li_(2)S_(2)/Li_(2)S,and"shuttle effect"of polysulfide in the practical application of lithium sulfur(Li-S)batteries.Featured a unique three-dimensional structure,multi-walled carbon nanotubes(MWCNTs)were taken as diaphragm coating(YTC)to restrain the shuttle effect of polysulfide.The results showed that the initial discharge capacity of YTC battery was 974.3 mAh·g^(-1) at 0.10 C rate,and remained 622 mAh·g^(-1) after 200 cycles,indicating that coating MWCNTs on diaphragm combined with positive electrode material could improve the conductivity of the material and inhibit the shuttle effect of polysulfide,showing good cycling performance and coulomb efficiency.