A novel CuS/graphene-coated separator for suppressing the shuttle effect of lithium/sulfur batteries

Herein, we demonstrate a facile synthesis process to fabricate and deposit flower-like CuS/graphene nano- composite on a multi-functional separator for efficient immobilization of polysulfides of lithium/sulfur (Li/S) batteries. Admirably, as-prepared CuS/graphene composite endows enriched oxygen-functional groups and excellent electrical conductivity for cathode area. The introduction of CuS/graphene-coated separator effectively reduced the dissolution of lithium polysulfides as well as enhanced the integrity of the sulfur cathode for Li/S batteries. The cell with these modified separator delivered an enviable discharge capacity of 1302 mAh g(-1) at 0.2 C, as well as an excellent reversible capacity of 760 mAh g(-1) after 100 cycles. Furthermore, an outstanding rate capability of 568 mAh g(-1 )at 3.0 C has been achieved in the cell with CuS/graphene-coated separator. The results reveal that CuS/graphene-coated separator shows an admirable potentiality to boost the performance of next-generation Li/S batteries.