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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.

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Lithium−sulfur (Li−S) batteries have received paramount attention as a next-generation energy storage device due to their remarkably high specific capacity (1675 mAh g −1 ), energy density (2600 Wh kg −1 ), and cost-effectiveness compared to the forefront lithium-ion batteries. However, certain issues still hamper the smooth working of Li−S batteries, which need to be addressed to fill the gap between fundamental research and commercialization. Polymer binders, as an inevitable part of the cathode structure, play a vital role in upholding the structural robustness and firmness of the electrode. However, conventional binders like PVDF are not capable of effectively accommodating the large volume changes within the electrode, facilitating electronic/ionic conductivity, entrapping the soluble polysulfide intermediates, and enhancing polysulfide redox kinetics. Therefore, novel multifunctional binder designs are adopted in Li−S batteries to tackle the above-mentioned issues. This review summarizes the recent progress in this research area employing advanced multifunctional polymer binders in Li−S batteries. The action of the binder through various mechanisms is discussed in detail. The role of binder is given immense attention in the emerging field of various energy storage devices, including Li−S batteries, and, thus, here discussed as well.

Intercalation pseudocapacitance has been recognized as a new type of charge storage mechanism in crystalline metal oxides, wherein Li + intercalation is not limited to surface structures, instead extended to the bulk crystalline framework of the material. This may possibly narrow the performance gap between pseudocapacitors and batteries. Hitherto, very few crystalline materials have been found to exhibit such an intrinsic capacitive property. Here, we report for the first time that the inverse spinel LiCoVO 4 exhibits intercalation pseudocapacitive Li + storage property in aqueous electrolyte. Micro-and nanocrystalline LiCoVO 4 were synthesized via conventional solid-state reaction and hydrothermal reaction followed by calcination, respectively. In particular, nanocrystalline LiCoVO 4 demonstrated better Li + intercalation benefited from its small crystallite size with highly exposed Li + selective crystallographic pathways toward electrolyte. The LiCoVO 4 nanocrystals demonstrated excellent capacitive performance, including high specific capacitance (929.58 F g −1 at 1 A g −1 ) and cycling stability. Moreover, asymmetric hybrid cells were assembled using nanocrystalline LiCoVO 4 and MWCNT as the positive and negative electrode, respectively. The hybrid cells exhibited an unprecedented energy density (148.75 Wh kg −1 at a power density of 264.6 W kg −1 ) and superior cycling stability (94% capacitance retention after 5000 cycles).