3D Visualization of Liquid Water Penetration from MPL to Substrate Layer in PEFC Using in-Situ X-Ray Tomographic Microscopy

X-ray tomographic microscopy (XTM) is used to clarify liquid water behavior in polymer electrolyte fuel cell (PEFC). It was difficult to acquire 3D image of liquid water in gas diffusion layer (GDL) by using laboratory-based XTM because the intensity of laboratory-based X-ray is lower than that of synchrotron-based X-ray. By improving the cell, 3D visualization of liquid water in substrate layer and cracks of micro porous layer (MPL) is achieved. It is also shown that liquid water in substrate layer tends to remain in the bigger pore diameter.