Effect of Spatially-Varying GDL Properties and Land Compression on Water Distribution in PEM Fuel Cells

A multi-dimensional two-phase model of polymer electrolyte fuel cells is developed and employed to investigate through-plane water profiles with spatially-varying properties of gas diffusion layers (GDL) being accounted for. Both one-dimensional (1-D) and 2-D model predictions of liquid water profiles are presented. We find that the GDL properties can significantly affect the liquid through-plane profiles and local features, for example, liquid water may be trapped due to the spatial variation in GDL properties. Furthermore, land compression can cause GDL property variation in the in-plane direction, altering liquid water distribution. Model predictions are compared with experimental data from both neutron radiography and X-ray imaging. Reasonably good agreements are obtained.