Cobalt-Embedded 3d Conductive Honeycomb Architecture to Enable High-Sulphur-Loading Li-S Batteries Under Lean Electrolyte Conditions

High sulphur loading and lean electrolyte conditions are important to achieve the high theoretical energy density of Li-S batteries. However, serious problems such as low sulphur utilization and fast capacity fade are typically experienced under low electrolyte/sulphur (E/S) ratios and high sulphur loading conditions. To address these issues, a cobalt-containing three-dimensional conductive honeycomb (Co@N-HPC) is proposed in this work as a material for sulphur cathodes. The good electrical conductivity and high density of catalytic sites of (Co@N-HPC) allow fast redox kinetics of lithium polysulfide (LiPS) in high-sulphur-loading electrodes. In addition, the hierarchical structure and good wettability by the electrolyte of Co@N-HPC facilitates electrolyte penetration and LiPS conversion, leading to a high utilization of sulphur under lean electrolyte conditions. Therefore, the as-developed cell exhibits a capacity retention of 76% over 500 cycles at 1 C. At a current density of 0.2 C, a volumetric capacity of 1,410 mAh cm −3 was attained with a sulphur loading of 5.1 mg cm −2 and an E/S ratio of 5 µL mg −1 . This work provides ideas for the development of lean electrolyte Li-S batteries with a high sulphur loading