Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
1272179 | International Journal of Hydrogen Energy | 2014 | 6 Pages |
•Neutron radiographs were used to study the water distribution in a 50 cm2 PEMFC.•The cross-flow flow field channels design was identified in the distributions.•The back-diffusion transport mechanism was clearly observed in the distributions.
Back-diffusion in PEM fuel cells is the water transport mechanism contributing to balance the water content profile in the membrane (in the through-plane direction), transporting water molecules from the cathode electrode towards the anode side of the membrane. In this technical note, neutron radiographs are presented for a 50 cm2 N-117 fuel cell with serpentine flow field, where the effect of the back diffusion transport mechanism is clearly identified, in the form of crossed patterns following the cross-flow layout of the flow field. The back diffusion water transport is evident despite the high thickness of the N-117 membrane.