Robust Polymer Electrolyte Membranes with High Ambient-Temperature Lithium-Ion Conductivity via Polymerization-Induced Microphase Separation.

Mechanically robust polymer electrolyte membranes (PEMs) exhibiting high ionic conductivity at ambient temperature are a prerequisite for next-generation electrochemical devices. We utilized a polymerization-induced microphase separation (PIMS) strategy to prepare nanostructured materials comprising continuous conducting nanochannels intertwined with a mechanically and thermally robust cross-linked polymeric framework. Addition of succinonitrile (SN) rendered the poly(ethylene oxide)/lithium (Li) salt conducting domains completely amorphous, resulting in outstanding conductivities (∼0.35 mS/cm) at 30 °C. Concurrently, a densely cross-linked polystyrene framework provided mechanical robustness (modulus E' ≈ 0.3 GPa at 30 °C) to the hybrid material. This work highlights a facile, single-pot strategy involving a homogeneous liquid reaction precursor that yields a high-performance ion-conducting membrane attractive for lithium-battery applications.