Effect of Water Balance in Ionomer Solution for Novel Membrane Electrode Assembly of Polymer Electrolyte Membrane Fuel Cells

The performance of membrane electrode assemblies (MEA) is considerably affected by water balance or content in ionomer solution. The three-dimensional structure of the ionomer in electrode is very important for getting higher current density in MEA. In this study, some representative water-based and alcohol-based commercial ionomers were compared for getting higher MEA performance under different humidity level. The contact angle of the catalyst layer was measured to determine the variation in wetting properties with different ionomer solution. Various MEAs with different electrode combination were tested in single cell station. And some electrochemical techniques were applied to this MEA such as polarization curve, electrochemical impedance spectroscopy (EIS) and cyclic voltammetry. The results show that a MEA of water-based ionomer as anode and alcohol-based ionomer as cathode exhibits higher performance at most humidity levels.