碳膜夹层锂硫电池的电化学性能

选取Super-P（SP）、KB或MWCNTs导电碳膜夹层，并置于硫电极与隔膜间组装成扣式锂硫电池.相关评估结果表明，碳膜夹层可显著提高锂硫电池循环性能，硫电极（载硫量为80%，by mass，下同）循环40周后比容量均在800 mAh·g^-1以上. 上述三种碳膜的物理性质有较大差异，导致相应电池具有不同电性能. KB碳膜夹层电池呈现较强的电化学极化效应；SP碳膜夹层电池循环初期可释放出最高的比容量，而循环稳定性较差；MWCNTs碳膜可视为较适宜的导电碳夹层材料.

Effects of Carbon Interlayer on Electrochemical Performance of Lithium-Sulfur Cell

Three kinds of conductive carbon films were prepared with Super-P (SP), KB and MWCNTs, and then the as-prepared carbon films were applied as an interlayer between a sulfur electrode and a separator for constructing a coin-type lithium-sulfur (Li-S) cell, respectively. The assessment results show that all the cells delivered the reversible capacities higher than 800 mAh·g^-1 after 40 cycles when the sulfur loading was up to 80% (by mass) in the sulfur electrode. Due to significant differences of physical properties among the carbon materials，the cell with a KB interlayer exhibited higher electrochemical polarization; the cycling performance of the cell with a SP interlayer was poorer than that of the other cells, although the discharge capacity was the highest in the initial cycles; MWCNTs film was the best choice as an interlayer in the Li-S cells.