论文部分内容阅读
The'shuttle effect'of polysulfide causing rapid capacity fade and low coulombic efficiency of high energy storage lithium-sulfur (Li-S) batteries.Herein,a sandwich structure of bamboo charcoal/sulfur coating by aluminum fluoride (BC@S@AlF3) composites is designed and fabricated for the first time.The as-designed cathode exhibited excellent electrochemical properties and stable capacity retention.The initial capacity reaches 1119 mA h/g and the capacity after 100 cycles is 869 mA h/g at 0.5 C,which is much stable than that of composite materials without bamboo charcoal or AlF3 coating.Moreover,the BC@S@AlF3 cathode presents excellent long-term capacity stability with a capacity decay of 0.073％ per cycle during 500 charge/discharge cycles at 1 C,offering a potential for use in high energy Li-S batteries.The physical confinement,chemical anchoring,and catalysis conversion for active sulfur are achieved simultaneously with the AlF3 coating and bamboo charcoal core with porous structure.