Insight Into All‐Solid‐State Lithium‐Sulfur Batteries: Challenges and Interface Engineering at the Electrode‐Sulfide Solid Electrolyte Interface

ABSTRACT Challenges such as persistent shuttle effects, fast capacity fading, and safety concerns in conventional liquid lithium‐sulfur (Li─S) batteries have significantly hindered their commercialization. Replacing liquid electrolytes with inorganic solid electrolytes has emerged as a promising strategy to overcome these limitations, owing to their intrinsic safety and shuttle‐effect‐free characteristic. Despite great advancements in all‐solid‐state lithium‐sulfur batteries (ASSLSBs), numerous challenges persist, including low active material utilization, large volume change during cycling, electrolyte‐electrode interfacial reactions, and the high proportion of inactive components. This review provides a comprehensive overview of recent advancements in ASSLSBs, with a particular focus on sulfur cathode design strategies aimed at enhancing ionic and electronic conducting percolations and mitigating the interfacial stresses caused by sulfur's volume changes during cycling. Furthermore, the interfacial challenges at the composite cathode‐electrolyte and electrolyte‐anode interfaces are critically analyzed, and pathways for engineering interfaces to maximize performance and extend battery lifetime are discussed. Finally, the preparation of thin electrolyte membrane, which is closely tied to the overall energy density of ASSLSBs, is thoroughly examined. By addressing these key aspects, this review aims to provide valuable insights into the critical factors affecting the performance of sulfide‐based ASSLSBs and guide future research efforts toward their commercialization.