Recent Progress in All-Solid-State Lithium−Sulfur Batteries Using High Li-Ion Conductive Solid Electrolytes

Rechargeable lithium−sulfur (Li−S) batteries are one of the most promising next-generation energy storage systems due to their extremely high energy densities and low cost compared with state-of-the-art lithium-ion batteries. However, the main obstacles of conventional Li−S batteries arise from the dissolution of lithium polysulfides in organic liquid electrolytes and corresponding safety issues. To address these issues, an effective approach is to replace conventional liquid electrolytes with solid-state electrolytes. In this review, recent progress in the development of solid electrolytes, including solid polymer electrolytes and inorganic glass/ceramic solid electrolytes, along with corresponding all-solid-state Li−S batteries (ASSLSBs) and related interfacial issues at the electrode/electrolyte interface, will be systematically summarized. In addition, the importance of various solid-state lithium ion conductors in ASSLSBs will be discussed followed by detailed presentations on the development of various forms of sulfur-based positive electrode materials (e.g., elemental sulfur, lithium sulfide, metal sulfides, lithium thiophosphates, and lithium polysulfidophosphates) along with key interfacial challenges at the electrode/solid electrolyte interface (cathode/SE and anode/SE). Finally, this review will provide a brief outlook on the future research of ASSLSBs.