The nature andconcentration of the incorporated salt have a major influence on the properties of solid polymer electrolytes. In particular the anion has a mojor influence on phase composition and conductivity. We propose to synthesize and evaluate a new family of highly alkylated and peralkylated derivatives of carborayl anion CB11H12 (1) that hold the promise of affording a superior solid polymenr electrlyte for lithium batteries. The first member of the family CB11Me12 (2) has been prepared in our laboratory and ist structure, thermal stability, solubility, solution conductivity, and chemical and electrochemical stability, processability and safety. We propose to optimize such properties of carboranyl anions as their oxidation potential, chemical and electrochemical stability, solubility in hydrocarbon polymers, and ionic conducivity when incorporated into various polymers. We further propose to prepare polymenrs with covalently incorporated anions by copolymerization or cross-linking, and toevaluate the conduting properties of thus produced polyelectrolytes using test cells and AC Impedance Spectroscopy
