On the Effect of Clamping Pressure and Methods on the Current Distribution of a Proton Exchange Membrane Water Electrolyzer

Abstract

The heterogeneity of the local current distribution (LCD) of proton exchange membrane water electrolysis cell (PEMWE) has a significant effect on its degradation. More heterogeneous LCD leads to faster degradation rate and vice versa. LCD is affected by the amount of clamping pressure and methods. In this work, LCD is measured at the cathode side of 50 cm2 PEMWE cell at different clamping pressures and methods; bolting the cell with 8 bolts around the active area and compressing the overall area of the end plate using pneumatic set-up. S++® Current Scan Lin is used for LCD measurements, where the segmented plate is placed between the current distributor and flow field plate. Initial results show that, increasing the torque in the bolted cell results in heterogeneous LCD and vice versa for the pneumatically compressed cell. Also it is concluded that, higher PEMWE cell performance does not necessary mean homogeneous LCD.