Ceramic-in-Polymer Composite Solid Electrolyte Enabled by Metal–Sulfur Interactions with Enhanced Li-Ion Conductivity

, exceeding the vendor-reported conductivity of pure LLZO. In addition, the sulfur-modified LLZO-in-PEGDA composites exhibited improved toughness and stretchability, suggesting the potential dual role as a protective layer for electrode materials. The metal/sulfur-interaction-enabled dual modification offers a promising strategy that can be broadly applied to the rational design of ceramic/polymer composite materials.