A Review of Solid-State Lithium-Sulfur Battery: Ion Transport and Polysulfide Chemistry

The lithium-sulfur (Li-S) battery has long been a research hotspot due to its high theoretical specific capacity, low cost, and nontoxicity. However, there are still some challenges impeding the Li-S battery from practical application, such as the shuttle effect of lithium-polysulfides (LiPSs), the growth of lithium dendritic, and the potential leakage risk of liquid electrolytes. Substitution of liquid electrolytes with solid-state electrolytes (SSEs) is an effective strategy to relieve or even solve these problems. This review focuses on the most crucial issues of the solid-state Li-S battery (SSLSB) and exhibits the recent progress in these fields. SSEs applicable in the Li-S battery including inorganic glassy ceramics and ceramics, organic polymers, and inorganic-organic hybrid electrolytes are reviewed. Then, the establishment of Li-ion pathways inside the cathode is discussed in detail. We also probe into the unique polysulfide chemistry of the Li-S battery and expound our opinions. Finally, conclusions and perspectives are outlined for the further development of SSLSBs.