Proton-exchange membrane fuel cells (PEMFC) are regarded as a possible alternative power source for stationary and mobile applications. Due to the catalyst costs, many researchers have been studying the membrane and the electrode assembly (MEA) manufacturing processes that can reduce the content of Pt in the electrocatalyst layer while maintaining the performance. The MEA is the heart of the PEMFC and the catalyst plays an important role in the fuel cell operation.There are different methods to prepare MEA. In this work, the catalyst ink was straightly applied on the gas diffusion layer (GDL) by an aerograph. Then, this electrode was assembled to the membrane by hot press.From the point of view of operation, the main variables are: temperature, pressure and time of press. Operational range was established from previous experiments to find roughly the optimal conditions. Finally, these MEAs were tested in a 5 cm2 PEMFC. The operational temperature was 30°C. Due to higher temperatures it was difficult to keep the humidity of the membrane constant. The operational pressure and flow were constant throughout the experiments. Different techniques to characterize the MEAs, linear sweep voltammetry and cyclic voltammetry were applied. With these techniques the permeation of hydrogen and the electrochemically active surface area of electrode catalyst were determined.With the results obtained in the experiments, the optimal values of the fabrication parameters were established.
Observation of the Electrochemically active Surface Area in a Proton Exchange Membrane Fuel Cell
