Li–S batteries are becoming attractive due to their tremendous merits. In Li–S batteries, the sulfur (S₈) undergoes a two-electron redox reaction with Li, which can provide a high theoretical capacity of 1675 mA h g⁻¹ and can achieve high energy densities (2600 Wh kg⁻¹) that are three-fold higher than those of transition metal oxide cathodes.^1,2 Although Li–S battery technology has made great progress due to such intensive research efforts,^3-5 effective approach for high performance Li–S battery to deliver a high capacity and good capacity retention with high sulfur loading has not been suggested yet.

Herein, a novel lithium–sulfur cell design is proposed, which consists of sulfur and magnesium–aluminum-layered double hydroxides (MgAl-LDH)–carbon nanotubes (CNTs) composite cathode with a modified polymer separator produced by dual side coating approaches (one side: graphene and the other side: aluminum oxides). The composite cathode functions as a combined electrocatalyst and polysulfide scavenger, greatly improving the reaction kinetics and stabilizing the Coulombic efficiency upon cycling. The modified separator enhances further Li⁺-ion or electron transport and prevents undesirable contact between the cathode and dendritic lithium on the anode. The proposed lithium–sulfur cell fabricated with the as-prepared composite cathode and modified separator exhibits a high initial discharge capacity of 1375 mA h g⁻¹ at 0.1 C rate, excellent cycling stability during 200 cycles at 1 C rate, and superior rate capability up to 5 C rate, even with high sulfur loading of 4.0 mg cm⁻². In addition, the findings that found in postmortem characterization of cathode, separator, and Li metal anode from cycled cell help in identifying the reason for its subsequent degradation upon cycling in Li–S cells.