Abstract: Multi-walled carbon nanotubes(MWCNTs) film was used as the interlayer between the positive electrode and the separator to check the dissolution and dispersion of polydulfides,which reduced the loss of active material and improved the capacity and cycle performance of lithium-sulfur(Li-S) batteries. The morphology and structure are characterized by transmission electron microscopy (TEM) and scanning electron microscopy(SEM). The electrochemical test showed that the initial discharge capacity of the Li-S batteries with the MWCNTs interlayer reached 1352mA·h/g and the Coulomb efficiency was close to 100%. The discharge capacity remained 1028mA·h/g after 20 cycles. The batteries maintained specific capacities of 902mA·h/g,782mA·h/g and 509mA·h/g at the current rate of 1C,2C and 5C respectively.

Key words: lithium-sulphur batteries, multi-walled carbon nanotubes, interlayer, shuttle effect

摘要： 以多壁碳纳米管（MWCNTs）薄膜作为锂硫电池正极片与隔膜之间的夹层，可抑制多硫化物的溶解和扩散，阻止穿梭效应，减小活性物质的损失，提高锂硫电池的容量和循环性能。本文利用透射电子显微镜（TEM）和扫描电镜（SEM）等进行结构和性能的表征。电化学测试结果表明，含MWCNTs夹层的锂硫电池在0.2C倍率首次放电比容量达到1352mA·h/g，首次库仑效率接近100%，循环20次后比容量还保持在1028mA·h/g。在1C、2C和5C倍率下充放电，电池比容量分别达到902mA·h/g、782mA·h/g和509mA·h/g。

关键词: 锂硫电池, 多壁碳纳米管, 夹层, 穿梭效应