Separator Modification and Functionalization for Inhibiting the Shuttle Effect in Lithium-Sulfur Batteries

The shuttling effect of polysulfides through the separator is detrimental for the practical application of lithium-sulfur (Li-S) batteries. Tremendous efforts have been centered on inhibiting the shuttle effect by improving traditional separators or designing novel separators. Here, recent advances in addressing the shuttling effect through various strategies are overviewed and discussed. The methods of employing inorganic/carbonic ingredients to fabricate bilayer/trilayer separators with filtration and coating processing are evaluated. Functionalization of polyolefin-based separators to realize the electrostatic repulsion between oxygen/nitrogen groups and sulfur-containing species is also discussed. Then, composite separators incorporated with MOF(metal-organic framework)@GO(graphene oxide), GF(glass fiber)@Mxene, nanowires, etc. are analyzed. In the end, perspectives for realizing stable operation of Li-S batteries are presented for future research.