关键词: 锂硫二次电池, 介孔碳, S/C复合正极材料, 循环稳定性

Abstract: A sulfur/mesoporous carbon composite was prepared by thermally treating a mixture of sublimed sulfur and mesoporous carbon.The microstructure of the mesoporous carbon was characterized by BET analysis and X-ray diffraction(XRD).The electrochemical performance of the S/C composite as cathode materials was evaluated by the galvanostatic method.The results confirmed that the mesoporous carbon could not only greatly enhance the electrochemical activity of sulfur electrode,but also effectively confine the diffusion of dissolved polysulfides in organic electrolyte.As a result,the S/C composites showed high capacity,good cycle performance and excellent rate capability.The specific capacity of the S/C composite was more than 1200 mAh/g for the first discharge,and remained at 800 mAh/g after 100 cycles even at a high current density of 800 mA/g.

Key words: lithium-sulfur rechargeable battery, mesoporous carbon, S/C composite materials, cycling stability