Dual Passivation of Cathode and Anode through Electrode–Electrolyte Interface Engineering Enables Long-Lifespan Li Metal–SPAN Batteries
Yubin He, Peichao Zou, Seong‐Min Bak, Chunyang Wang, Rui Zhang, Libing Yao, Yonghua Du, Enyuan Hu, Ruoqian Lin, Huolin L. Xin
Abstract
The reliability and durability of lithium metal (Li0)–sulfur batteries are largely limited by the undesired Li0 plating-stripping irreversibility and the detrimental polysulfide dissolution, yet approaches that can simultaneously address the above anodic and cathodic problems are scarce. Herein, we report the stable operation of a Li0-SPAN (sulfurized polyacrylonitrile) battery via an anode–cathode dual-passivation approach. By combination of a fluorinated localized high concentration electrolyte (LHCE) and a Li3N-forming additive (TMS-N3), robust and highly conductive electrode passivation layers are formed in situ on the surface of both the Li0 anode and the SPAN cathode. The resulting highly reversible, dendrite-free, and high-density Li0 plating morphology enables a high Coulombic efficiency of 99.4%. Advanced tender energy X-ray spectroscopy also reveals the eliminated Li2S formation and minimized polysulfide dissolution in SPAN cathodes, leading to a high capacity of 580 mAh/gSPAN and stable cycling with negligible capacity decay (0.7%) for 800 cycles. This electrode–electrolyte interphase engineering strategy has tackled the major limitations of Li–S batteries in both ether- and carbonate-based electrolyte systems and under a wide temperature range from −10 to +50 °C, thus providing insightful guidelines for the rational design of highly durable and high-energy-density Li0-S batteries.