Safety is a key concern for high-power energy storage systems such as will be required for electric vehicles. Present lithium ion batteries, which use a flammable organic liquid electrolyte, lack inherent safety. Our approach in solving this problem is to replace the liquid electrolytes with a liquid-free polymer electrolyte. Data of the composition of the positive electrode, charge-discharge and cycle-life capability are presented. The cell using metallic Lithium anode and crosslinked polymer electrolyte P(EO/MEEGE/AGE)-LiTFSI showed a discharge capacity of 134 mAh g(-1) of LiCoO2 at 60 degreesC and 140 mAh g(-1) at 140 degreesC.