Advancing Li-S full cells: integrating a freestanding interlayer and reduced TiO2/S cathode with a pre-lithiated graphite anode

Official URL: https://dx.doi.org/10.1088/2515-7655/ae7645

Progress in sulfur cathodes and separator interlayers has substantially curtailed polysulfide shuttling and sluggish kinetics in Li–S batteries. However, the instability of lithium metal anodes remains a major barrier to commercialization. Replacing lithium with mature lithiated graphite is attractive, but ether-based electrolytes used in Li–S cells induce Li+/solvent co-intercalation and rapid failure of graphite electrodes. Building optimized interlayers and sulfur cathodes, this study focuses on making graphite fully compatible with ether electrolytes (DOL/DME). By systematically adjusting the lithium-salt concentration and LiNO3 additive, we found a finely tuned compositional regime in which the graphite electrode is free from solvent co-intercalation without markedly impairing cathode kinetics. This enabled the integration of an H–TiO2/S cathode, a thin freestanding PVDF/MS interlayer, and a lithiated graphite anode into a full cell, which delivered 1066 mAh⋅gsulfur−1 at 0.1 C (N/P = 0.87). The resulting prototype demonstrates that Li–S chemistry can operate without a lithium-metal anode, offering a practical route toward safer and more commercially viable Li–S batteries.