IONIC-CONDUCTION AND THERMAL-PROPERTIES OF POLY(ETHYLENE OXIDE) TM(CF3SO3)(3) ELECTROLYTE FILMS

The electrical conductivity and thermal behaviour of solid polymer ele ctrolyte films containing thulium triflate and poly(ethylene oxide) ha ve been studied. Homogeneous electrolyte samples were prepared by usin g solvent casting and hot-pressing techniques to produce films with a composition defined by the general formula (EO)(n)Tm(CF3SO3)(3), where n lies between 3 and 150. This electrolyte system was found to show a surprisingly high total ionic conductivity in compositions with large salt concentrations. These materials, with n between 3 and 5, were ap parently amorphous but crystallized slowly after prolonged annealing a t room temperature. Thermal analysis showed the presence of a broad me lting peak which may correspond to the fusion, or dissolution, of a sa lt-polymer complex. (C) 1998 Published by Elsevier Science Ltd. All ri ghts reserved.