Solid Polymer Electrolytes Derived from Oligomeric Poly(ethylene oxide) Chain-Grafted Crosslinked Polystyrene Microspheres

A new class of lithium-ion conducting Solid Polymer Electrolytes (SPEs) has been derived from oligomeric Polyethylene Oxide (PEO)-grafted Cross-linked Polystyrene (XPS) microspheres containing one or two lithium sulfonamide moieties. The SPE containing Li:O mole ratio of 1:8 displayed excellent ionic conductivity (in excess of 10-4S/cm at 25ºC) and good electrochemical stability (4.3 volts versus Li/Li+). Thermal properties of these SPEs have also been investigated with Differential Scanning Calorimetry (DSC) and Thermogravimetric Analysis (TGA). These new SPEs possess amorphous character with a glass Transition Temperature (Tg) around 135ºC, and no significant thermal decomposition until 420ºC. Synthesis and characterization including surface morphologies of these SPEs are described.