Effect of Interfacial Polymer Layer on Ion Transport in Hybrid Ceramic-Polymer Solid Electrolytes

Hybrid ceramic-polymer membranes have emerging as new solid-state electrolytes (SSE) to promise high ion conductivity, strong mechanical strength, and easy processing, however the inherent incompatibility between inorganic ceramic and organic polymer remains a great challenge for their applications. In this work, we investigated the interaction of polyethylene oxide (PEO) based copolymer interfacial layer with both inorganic garnet-type LLZO ceramic and PEO electrolytes. With the interfacial copolymer layer, we observed much improved interfacial contact between LLZO and PEO membranes with considerably lowered bulk resistivity. We further examined the effect of copolymer content and interfacial layer thickness on the ion conductivity and electrochemical window of inorganic-organic composite SSEs.