A polypyrrole-coated acetylene black/sulfur composite cathode material for lithium–sulfur batteries

作     者：Wu Yang Wang Yang Jiani Feng Xiujuan Qin 

作者机构：Hebei Key Laboratory of Applied Chemistry College of Environmental and Chemical Engineering Yanshan University State key Laboratory of Metastable Materials Science and Technology Yanshan University 

出 版 物：《Journal of Energy Chemistry》 (能源化学（英文版）)

年 卷 期：2018年第27卷第3期

页      面：813-819页

核心收录：

学科分类：0808[工学-电气工程] 08[工学] 0805[工学-材料科学与工程（可授工学、理学学位）] 080502[工学-材料学] 

基　　金：the financial support from the National Natural Science Foundation of China (No. 51674221) 

主　　题：Lithium sulfur batteries Acetylene black Polypyrrole Core–shell 

摘      要：Lithium–sulfur batteries are promising next-generation energy storage devices beyond conventional lithium ion batteries. However, it suffers from rapid capacity fading and poor cyclic stability. Here we report a facile in situ sulfur deposition and chemical oxidative polymerization method for preparing acetylene black/sulfur@polypyrrole（AB/S@PPy） composite as a cathode material for lithium–sulfur batteries. It is demonstrated that PPy is covered uniformly onto the surface of the AB/S composite forming a core–shell structure. In the structure, AB in the matrix and PPy on the surface acts as a combined conductive framework to provide ions and electrons transport pathways, and to inhibit the dissolution or diffusion of polysulfide into the electrolyte. The as-designed AB/S@PPy composite exhibits excellent rate capability and cyclic stability. The initial discharge specific capacity is as high as 1179.4 m Ah/g, and remains at769.3 m Ah/g after 80 cycles at 0.2 C. Even at a high rate（0.5 C）, a maximum discharge capacity of 811.1 m Ah/g is still achieved for the AB/S@PPy composite after activation, and the capacity retention is over62.5% after 200 cycles.