Polyepichlorhydrin membranes for alkaline fuel cells: Sorption and conduction properties

Polymer electrolytes, using a poly(epichlorhydrin-allyl glycidyl ether) copolymer as matrix, are shown to perform well in alkaline fuel cell electrolyte. An anion-conducting network is obtained by the incorporation of cyclic diamines, 1,4-diazabicyclo[2.2.2] octane (DABCO) and 1-azabicyclo [2.2.2] octane (quinuclidine). The physicochemical and electrochemical characteristics are evaluated. The best conductivity of 1.3. 10(-2) S/cm is obtained at 60 degrees C and a relative humidity of RH = 98%. Ionic conductivity is particularly sensitive to relative humidity. To gain insight into the OH- conduction mechanism and the role of water, sorption measurements versus water activity, differential scanning calorimetry, and NMR measurements are carried out.