Enhanced performance of lithium polymer batteries using a V2O5-PEG composite cathode

A new concept is proposed to realize solid-state high-performance lithium p olymer batteries in which two different polymers are used as ionically cond uctive matrices in the cathode and in the separator. A solid, low molecular weight poly(ethylene glycol) was used in the cathode while a blend with a higher molecular weight poly(ethylene oxide) (PEO) was used in the separato r. The enhanced transport properties in the cathodic compartment allow us t o discharge the battery (190 mAh g(-1)) at a moderate temperature (65 degre es C) in a reasonable time (about 3.3 h). Batteries cycled at 100 degrees C showed enhanced performance with respect to PEG-based batteries. At a powe r density of about 416 Ur kg(-1), energy density as high as 460 W kg(-1), b ased on the weight of the active material, was achieved in about 1 h of dis charge. The work was developed within the ALPE (Advanced Lithium Polymer El ectric Vehicle Battery) project, an Italian integrated project devoted to t he realization of lithium polymer batteries for electric vehicle applicatio ns, in collaboration with the Osaka National Research Institute. (C) 2000 E lsevier Science SIA. All rights reserved.