Nanostructured Inorganic−Organic Composites as a Basis for Solid Polymer Electrolytes with Enhanced Properties

Abstract

A family of lithium electrolyte materials based on a polymer−inorganic hybrid is described. The base material is a blend of poly(ethylene oxide) and an organic−inorganic composite made from polyether-functionalized methoxysilanes and aluminum alkoxides. Lithium is incorporated through addition of a salt. The resulting materials are shown through a combination of methods, including transmission electron microscopy and solid-state NMR, to consist of an amorphous inorganic network, with nanoscopic voids, which stabilize the added polymer. The composite polymer electrolytes show good resistance to crystallization and good conductivity, as determined by differential scanning calorimetry and impedance measurements, respectively. The nanoscale structure of the underlying inorganic material is concluded to be responsible for the bulk properties of the system, especially those that differ from the properties of similar, pure salt-in-polymer electrolytes.