Measurement of Ionic Conductivity of PEM Water Electrolyzer Electrodes

In this paper, the hydrogen pump technique is used to study the proton-transport resistance of polymer electrolyte membrane water electrolyzer electrodes. Three catalyst coated membranes made by sandwiching two membranes together were prepared, with two of them including an intermediate pseudo catalyst layer (PCL) with 35 and 55 %wt. ionomer loadings. The proton-transport resistance was calculated by subtracting the overall resistance of the cell without a PCL from that with a PCL. The effect of the ionomer loading on the PCL proton conductivity was studied. As expected, the proton conductivity increased with increasing ionomer loading. The results are in line with the expectation based on the literature data and show that the hydrogen pump technique can be used to obtain the proton-transport resistance of the electrodes.