Impact of membrane-electrode assembly fabrication technique on PEM fuel cell performance

PEM fuel cell performance is limited by three main sources of polarization losses: activation, ohmic and mass transport. Relative magnitudes of these differ depending upon the type of catalyst, membrane and substrate used in the fuel cell. More importantly there can also be a large variation in these losses between cells having the same components, due to the different fabrication techniques used in making the Membrane-Electrode Assembly (MEA). Even for a particular technique like screen-printing, the processing conditions alter the performance due to the different polarization losses (1). These differences become more significant at higher operating cell temperature and lower relative humidity operation. Catalyst coated membranes (CCMs) were made for a PEM fuel cell using screen-printing or the decal transfer method. Fuel cell performance was compared between cells made under different processing conditions. Effects of catalyst drying temperature, amount of propylene glycol in the catalyst ink and membrane used were studied on fuel cell performance.