Polymer gel electrolytes based on oligomeric polyether/cross-linked PMMA blends prepared via in situ polymerization

Very-low-vapor-pressure oligomeric polyether electrolytes blended with and dimensionally stabilized by cross-linked poly(methyl methacrylate) (PMMA) are prepared via in situ polymerization. The synthesized polymer gel electrolytes (PGEs) are freestanding films with excellent dimensional stability, mechanical integrity and strength. They exhibit high ionic conductivity at room temperature reaching 4.3 × 10−4 S/cm for the highest conducting sample and exceptional thermal stability. The oligomeric polyether and PMMA appear to have molecular level interaction in the blends and the PGEs remain a single phase from at least −50 to 200 °C, potentially enabling their application in advanced batteries in wide temperature ranges. The novel in situ polymerization process allows precise control of the composition of the PGEs and can enable in situ fabrication of advanced cells.