Abstract: The present work aimed to restrain shuttle effect of lithium-sulfur (Li-S) batteries and improve the cycle perfor-mance, and made an attempt to utilize dithiothreitol (DTT) as scission reagent to prevent dissolution of lithium polysulfur (LiPS). The prefabricated MWCNTs paper was immersed in the DTT solution and dried to obtain a DTT interlayer, which was subsequently located between the cathode disk (with a sulfur areal loading of 2 mg/cm2) and the separator of a Li-S coin half-cell. The morphological and structural observation over the DTT interlayer by scanning electron microscopy (SEM) validated the uniform dispersion of DTT in the MWCNTs paper. The electrochemical test showed that the Li-S half-cell with the DTT interlayer possesses an initial discharge capacity of 1 288 mAh/g and a Coulombic efficiency approaching 100%, and moreover, maintains specific capacities of 650 mAh/g, 600 mAh/g and 410 mAh/g under the current rates of 0.5C, 2C and 4C respectively. Our experiment indicated DTT can effectively slice high-order LiPS and hinder its migration to the anode, and in consequence, significantly improve the cycle stability and Coulombic efficiency of Li-S battery.
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