Abstract:
A strategy was reported to obtain high capacity with long cycle life by introducing a molybdenum disulfide (MoS
2) coating on the separator. MoS
2 which was synthesized by a facile, one-pot hydrothermal method was coated on the separator by simple pumping filtration without any binder to inhibit the polysulfide shuttling effect. The morphology and physical property of MoS
2 and the separator coated with MoS
2 were characterized by SEM、XRD and BET. The electrochemical performances of lithium sulfur batteries(Li-S batteries) were studied by electrochemical workstation and battery test station. In spite of the use of a simple sulfur-carbon black mixture as cathode, the Li-S battery with a MoS
2-coated separator offered outstanding performances with an initial capacity of 1 010 mA·h/g and 432 mA·h/g after 150 cycles at 400 mA/g. In the same conditions, the Li-S battery with a Celgard separator offered performances with an initial capacity of 816 mA·h/g and 297 mA·h/g after 150 cycles at 400 mA/g. The improved results could be owned to the MoS
2 coating, which not only reduced the battery resistance but also blocked the diffusion of soluble polysulfides avoiding shuttle effect during cycling.