Progress and Prospects of Inorganic Solid-State Electrolyte-Based All-Solid-State Li–S Batteries

All-solid-state lithium–sulfur batteries (ASSLSBs), a promising alternative to liquid lithium–sulfur batteries, are expected to alleviate the shuttle effect, reduce material loss, and achieve a compact structure. However, ASSLSBs face challenges in ionic conductivity and stability of solid electrolytes, optimization of sulfur cathodes, and electrolyte/electrode interfaces. This review summarizes recent research progress and strategies addressing these issues, focusing on oxide and sulfide-based electrolytes. Furthermore, it emphasizes the crucial role of rational optimization of sulfur cathode materials in composition, structure, and microstructure for constructing efficient ion/electron transport networks, and explores methods to solve chemical/electrochemical and physical interface issues. Additionally, it addresses challenges associated with the lithium anode and its interface problems, covering strategies, such as lithium alloy formation, 3D electrode architecture, and interfacial buffer layer implementation. These approaches aim to enhance the stability and performance of the lithium anode in ASSLSBs. Finally, this review highlights the significance of in situ characterization techniques for revealing reaction mechanisms, providing insights into phase composition, elemental chemical states, and dynamic structural transformations within the batteries, crucial for developing high-performance ASSLSBs.