Modeling of Catalyst Degradation in PEM Fuel Cells Applied to 3D Simulation

The durability of fuel cell stacks is a crucial topic on their way to commercialization. The most sensitive component of the PEM fuel cell is the cathode catalyst layer, since the catalyst material (usually platinum) and its support (usually carbon) are highly sensitive to potential, temperature and humidity changes which occur permanently during the fuel cell operation. The following degradation mechanisms are associated with the catalyst particles and their support:
• Carbon support corrosion, carbon oxidation, platinum oxidation
• Platinum dissolution and redeposition
• Particle detachment and agglomeration
In this work, an electrochemical model for above mentioned degradation effects is presented. The model is implemented in a commercial CFD code. Simulation results on a three-serpentine channel PEM fuel cell with an active area of 25 centimeter square are compared to measurements under various temperatures and humidities. The experimental data are obtained with a segmented test cell from S++ (Germany) and a G60 PEM fuel cell test station from Greenlight (Canada) using respective degradation protocols and test conditions proposed by the US Department of Energy.