context: Utilization of ceramic SE based separators is also an interesting strategy that can potentially solve problems associated with the S cathode and Li anode. Thanks to their high shear modulus, both the polysulfide shuttle and the Li dendrite growth can be mechanically suppressed. Among various inorganic ceramic SEs, Li–garnet (LLZO) is of particular interest since it offers a relatively high (electro)-chemical stability with Li metal, a much wider potential window compared to other SEs, and a high shear modulus (61 GPa for LLZO; 4.2 GPa for Li). However, the surface impurities/roughness and brittle nature of LLZO SE restrict its intimate contact with Li and other solid-state cathode materials. With S as the cathode material, the electrode/electrolyte integration will be even more challenging considering the enormous volumetric expansion during the conversion reaction with Li. In this regard, surface modification strategies including the use of thin nanometric layer coatings, and 3D interfacial architectures, or the implementation of polymer, gel and liquid interlayers have been used to keep the electrode|SE contacts intact and stabilize the interfacial ionic transport. Using Li ion conducting gel/liquid interlayers instead of using solid interlayers may prove to be an even better strategy due to their inherent tendency to penetrate through the porous structures and hence to access a greater surface area of the composite cathode.
answer: S 