Characterization of Solvent-Free Polymer Electrolytes Consisting of Ternary PEO–LiTFSI–PYR[sub 14] TFSI

The physical properties and electrochemical performance of solvent-free polymer electrolytes, consisting of poly(ethylene oxide) [P(EO)] with and -butyl--methylpyrrolidinium salts of bis(trifluoromethanesulfonyl)imide (TFSI), are reported. The addition of the room-temperature molten salt to the conventional polymer electrolyte results in a significant enhancement of the ionic conductivity (to at ). batteries making use of this new family of solid polymer electrolytes have shown a very promising low-temperature cycle life. It was found that a cell at can deliver during the first discharge, corresponding to 90% of the nominal specific capacity , and a promisingly low capacity fading of about 0.2%/cycle over 500 cycles.