Elastomers consisting of a copolymer of epichlorohydrin and ethylene oxide
were studied as solid polymer electrolytes in polymer/KOH systems. This alk
aline solid polymer electrolyte exhibits a high ionic conductivity at room
temperature, typically 10(-3) S cm(-1), as measured by electrochemical impe
dance spectroscopy. Moreover, it exhibits a good anionic transference numbe
r, namely 0.93, as determined by a technique derived from the Hittorf metho
d. The potential stability window (0.9 V) has been determined by cyclic vol
tammetry. Initial tests concerning a nickel/metal hydride secondary battery
and a zinc/air primary cell, containing this solid polymer electrolyte, sh
ow good performance of these systems in such electrolyte, at different temp
eratures. (C) 2000 Elsevier Science Ltd. All rights reserved.