In an effort to develop polymer electrolytes suitable for high temperature electrochemical operation, a polymer electrolyte based on the lithium salt doped copolymer of 1, 2, 4, 5-benzenetetracarboxylic dianhydride (PMDA), 4-aminophenyl ether (ODA), 2, 5-diaminobenzene sulfonic acid (DABSA) has been prepared. As LiCF3SO3 showed the best conductivity results within the lithium compounds, it was selected as our primary dopant. Infrared spectroscopy and electrical conductivity measurements have been performed to study film form of the copolymers. The ionic transport was found to exhibit an Arrhenius behavior over the temperature range of 160-300 degrees C, and the ionic conduction in these systems was found to be mainly due to the presence of lithium ions, which can be introduced into both oxygen and SO3- sites via doping but only into SO3- sites through ion-exchange.