【摘 要】
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In this present work,high stable C/S composites compatible with conventional carbonate-based electrolytes in Li-S batteries are fabricated by a novel sulfur vapor infusion into microporous carbon meth
【机 构】
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School of Materials Science and Engineering,University of Shanghai for Science and Technology,Shangh
论文部分内容阅读
In this present work,high stable C/S composites compatible with conventional carbonate-based electrolytes in Li-S batteries are fabricated by a novel sulfur vapor infusion into microporous carbon method following with solvent cleaning treatment.The C/S composite cathodes show high Coulombic efficiency,long cycling stability and good rate capability in the electrolyte of 1.0 M LiPF6+EC/DEC(1∶1 v/v),for instance,the reversible capacity of the treated C/S-50(50%S)cathode retains around 860 mAh/g even after 500 cycles and the Coulombic efficiency is close to 100%,which demonstrates the best electrochemical performance of carbon-sulfur composite cathodes using the carbonate-based electrolyte reported to date.It is believed that the chemical bond of C-S is responsible for the superior electrochemical properties in Li-S battery,that is,the strong interaction between S and carbon matrix significantly improves the conductivity of S,effectively buffers the structural strain/stress caused by the large volume change during lithiation/delithiation [1],completely eliminates the formation of high-order polysulfide intermediates,and substantially avoids the shuttle reaction and the side reaction between polysulfide anions and carbonate solvent,and thus enables the C/S cathode to use conventional carbonate-based electrolytes and achieve outstanding electrochemical properties in Li-S battery [2,3].The results may substantially contribute to the progress of the Li-S battery technology.
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