Operationally Robust Li–S Batteries at High\nCurrent Density Enabled by Metallic, Dual Sulfurphilic Nickel Boride

Achieving\nhigh sulfur loading and robust cycling in lithium–sulfur\n(Li–S) batteries under a high current density is challenging.\nEmploying metallic catalysts to improve the charge transfer and the\npolysulfide lithium polysulfide (LiPSs) conversion within the sulfur\ncathode under a high current with a high sulfur loading represents\na promising approach. This study explores metallic nickel boride (NiB)\nas a catalyst to enhance charge transfer and LiPS conversion. Theoretical\nand experimental results reveal that NiB accelerates sulfur redox\nkinetics, significantly improving the battery performance. With a\nsulfur loading of 5 mg cm<sup>–2</sup> cycled at 0.5 C, the\nNiB-based battery achieved a discharge capacity of 1239 mAh g<sup>–1</sup>, retaining 83.2% after 150 cycles. Even at a current\ndensity of 14.89 mA cm<sup>–2</sup>, it maintained a capacity\nof 590 mAh g<sup>–1</sup> with a low decay rate of 0.07%. This\napproach highlights the potential of metal boride catalysts for practical\nLi–S battery applications.