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Lithium-Sulfur (Li-S) batteries have been achieved great attention in recent years owing to its high theoretical capacity (1675 mAh/g) and energy density (2600 Wh/kg). PEG embedded MnO2/Sulfur composite was prepared via solid state reaction method. The composite was characterized by Transmission electron microscopy, scanning electron microscopy and X-ray diffractometer. MnO2 effectively suppress the diffusion of polysulfides and add a mechanical strength to the electrode. PEG binds the MnO2 and S, resulting in the minimization of active material loss and improves the electrochemical performance in lithium sulfur batteries. The PEG/MnO2/Sulfur composite exhibits discharge capacity of 647 mAh/g even after 30 cycles with appreciable sustainability. Therefore, the resulting PEG/MnO2/Sulfur composite exhibited as a desirable cathode material for Li-S battery.

A sulfur-Polyacrylonitrile (PAN)-acetylene black (AB) composite was synthesized via thermal treatment processes. The as-prepared ternary composite was characterized by expending transmission electron microscopy (TEM), X-ray diffraction (XRD), Brunauer-Emmett-Teller (BET) and electrochemical investigations. The improved electrochemical performance can be attributed to the formation of PAN layer, which can keep a tight contact between carbon and sulfur which leads to improve the conductivity. Moreover, the PAN can also act as a flexible cushion to accommodate volume changes of sulfur cathode as well as a barrier to trap soluble polysulfide intermediates during the charge-discharge process. The PAN-S-AB composite exhibits discharge capacity of 620 mAh/g even after 50 cycles with appreciable sustainability. Therefore, the resulting PAN/S/AB composite exhibited as a desirable cathode material for Li-S battery with great performance.

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Summary Lithium‐sulfur (Li‐S) batteries are deliberated as capable candidate in next generation of rechargeable batteries. It offers a significant specific capacity of 1675 mAh/g and high‐energy density (2600 Wh/kg). In this work, sulfur/MnO2/graphene oxide (GO) composite has been prepared by incorporating sulfur in different ratios with MnO2 and GO (10:20 and 20:10; SMG1 and SMG2) by solid state reaction and used as cathode for Li‐S battery. The obtained composites have been characterized for physical and electrochemical performances. The XRD spectrum display the sulfur is in orthorhombic structure and the presence of carbon has been confirmed by Raman analysis. The SMG2 composite with 70 wt% of sulfur displays a considerably embellished cycling performance (1610 mAh/g at an initial cycle at 0.1 C). The capacity and stability of the material is achieved by suppressing the polysulfides effectively. Low capacity fade, accommodation of volume change arising during cycling processes makes this positive electrode material competent for Li‐S battery application.