Assessment of Electrochemical Methods for Methanol Crossover Measurement through PEM of Direct Methanol Fuel Cell

It is important to have accurate, reliable, and convenient techniques for determining the methanol crossover rate through the polymer electrolyte membranes of fuel cells. In this work, various electrochemical techniques, namely; cyclic voltammetry, chronoamperometry and potentiometry, have been used to measure the methanol crossover rates using Nafion 117 membrane. The purpose of using different techniques is to suggest the best, most accurate and reliable technique for the determination of the methanol crossover rates. The permeability values obtained for the Nafion 117 membrane at 22C using the above techniques are in the range of 1.11 x 10 to 1.27 x 10 cm/s. The obtained permeability values are comparable to one another and correspond well with the literature values at similar conditions. However, potentiometric technique was found to be easier and gave better reproducibility as well as more data points.