Regulation of carbon distribution to construct high-sulfur-content cathode in lithium-sulfur batteries  

作　　者：Meng Zhao Yan-Qi Peng Bo-Quan Li Xue-Qiang Zhang Jia-Qi Huang 

机构地区：[1]School of Materials Science and Engineering,Beijing Institute of Technology,Beijing 100081,China [2]Advanced Research Institute of Multidisciplinary Science,Beijing Institute of Technology,Beijing 100081,China [3]Beijing Key Laboratory of Green Chemical Reaction Engineering and Technology,Department of Chemical Engineering,Tsinghua University,Beijing 100084,China

出　　处：《Journal of Energy Chemistry》2021年第5期203-208,共6页能源化学（英文版）

基　　金：supported by Scientific and Technological Key Project of Shanxi Province(20191102003);National Key Research and Development Program(2016YFA0202500);the National Natural Science Foundation of China(21776019);Beijing Natural Science Foundation(L182021)。

摘　　要：Lithium-sulfur(Li-S)battery is regarded as one of the most promising next-generation energy storage systems due to the ultra-high theoretical energy density of 2600 Wh kg^(-1).To address the insulation nature of sulfur,nanocarbon composition is essential to afford acceptable cycling capacity but inevitably sacrifices the actual energy density under working conditions.Therefore,rational structural design of the carbon/sulfur composite cathode is of great significance to realize satisfactory electrochemical performances with limited carbon content.Herein,the cathode carbon distribution is rationally regulated to construct high-sulfur-content and high-performance Li-S batteries.Concretely,a double-layer carbon(DLC)cathode is prepared by fabricating a surface carbon layer on the carbon/sulfur composite.The surface carbon layer not only provides more electrochemically active surfaces,but also blocks the polysulfide shuttle.Consequently,the DLC configuration with an increased sulfur content by nearly 10 wt%renders an initial areal capacity of 3.40 mAh cm^(-2) and capacity retention of 83.8%during 50 cycles,which is about two times than that of the low-sulfur-content cathode.The strategy of carbon distribution regulation affords an effective pathway to construct advanced high-sulfur-content cathodes for practical high-energy-density Li-S batteries.

关 键 词：Lithium-sulfur batteries High sulfur content High areal loading Double-layer carbon High energy density 

分 类 号：TM912[电气工程—电力电子与电力传动] TQ127.11[化学工程—无机化工]