Ion Pair Integrated Organic-Inorganic Hybrid Electrolyte Network for Solid-State Lithium Ion Batteries

A class of organic-inorganic hybrid electrolyte with ion pair integrated network (X-POSS-IL-LiTFSI) has been prepared by crosslinking of oligomeric octasilsesquioxanes grafted with imidazolium-based ionic liquids for solid state lithium ion battery applications. X-POSS-IL-LiTFSI is thermally stable and highly amorphous, and shows high ionic conductivities and excellent electrochemical stability. With further immobilization of a small fraction of ionic liquid, the ionic conductivity of X-POSS-IL-LiTFSI has been significantly improved, e. g. 1.4×10⁻⁴ S/cm at ambinet temperature, to the level required by the practical battery applications, while maintaining the demensional integity. The coin cells of lithium batteries with the plasticized X-POSS-IL-LiTFSI electrolytes exhibit high specific capacities at both ambient and elevated temperatures.