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Polysulfide dissolution and shuttling limit the capacity output and cycle life of lithium−sulfur batteries to a great extent. Separator modification using polar materials exploiting the ability to entrap polysulfides has been demonstrated as an effective approach to deal with the conundrum of polysulfide shuttling. Herein, a carbon nanotube/manganese sulfide nanocomposite is designed as a separator modifier in lithium−sulfur batteries for the first time. Furthermore, the carbon nanotube network provides a continuous network for rapid electronic conduction, imparts structural stability, and acts as a secondary barrier for polysulfides. Consequently, the cell displays an initial discharge capacity of 876 mAh g −1 at 0.5 C and sustains excellent stability with a retained capacity of 76% after 500 cycles. The self-discharge of the cell is also conspicuously reduced, maintaining a constant voltage for 100 h under open-circuit conditions. The electrochemical results represent an effective strategy to realize better performing Li−S batteries.

Lithium−sulfur batteries (LSBs) received worldwide attention because of its high theoretical capacity of sulfur, 1675 mA h g −1 . However, the low electrical conductivity of sulfur, dissolution of polysulfides (PS) in the electrolyte, and PS shuttle toward the Li anode restricted its reach to the market. In this paper, we present a porous carbon material with multifunctionalities derived from honeycomb (HC) used as a conductive host for sulfur for the first time. Honeycomb derived carbon−sulfur composite with 80% of sulfur [HCS (80%)] gives a high reversible capacity of 1101 mA h g −1 at the 0.1 C rate after 200 cycles with 82% capacity retention. The coating of HC onto the cathode film [HCS (80%)] yielded 92% capacity retention, where sulfur is sandwiched between the two conductive hosts. Therefore, the HCS (80%) composite electrode with coating of HC [HCS (80%)−HC] exhibits good improvement in both cycling performance and rate capability compared to bare cathode HCS, even though the sulfur content of the HCS composite is as high as 80%. Thus, HCS (80%)−HC would be a potent combination for highperformance LSBs.