High Resolution Neutron Radiography Imaging of Microporous Layers in PEFCs

Neutron radiography imaging polymer electrolyte fuel cells (PEFC) was performed with a high-resolution micro-channel plate (MCP) detector to investigate the liquid water distribution in micro-porous layers (MPL). In order to separate the role of MPL, a composite gas diffusion media (GDM) was constructed, in which portion of the cell has an MPL between the carbon paper substrate and the catalyst layer and the remainder does not. Neutron radiography images clearly showed the effect of the MPL, in which the overall saturation in the diffusion media was reduced with an MPL as predicted by earlier modeling studies. It is also seen that the MPL increases the water content in the anode;a result of the enhanced back-flux of water as predicted by earlier models