Mechanical response of carbon paper Gas Diffusion Layer under patterned compression

Tristan Le Carre (1) , Jean-François Blachot (1) , Jean-Philippe Poirot-Crouvezier (1) , Jerome Laurencin (2)

1 DEHT - Département de l'électricité et de l'hydrogène pour les transports
2 DTCH - Département Thermique Conversion et Hydrogène

The Proton Exchange Membrane Fuel Cell (PEMFC) performances are strongly impacted by the compression of the Gas Diffusion Layer (GDL). Despite its fibrous microstructure, this material is usually considered as a continuous medium and characterized with uniform loading. However, the GDL is subjected to a heterogeneous compression onto rib/channel patterns in the fuel cell assembly. In the present study, an original behavior of the GDL response is experimentally revealed when the material is loaded with a rib/channel pattern, compared to uniform compression. The tests are simulated by finite element modeling using a classical strain-dependent elastic law, using parameters fitted from uniform compression experiments. It is shown that the numerical results do not reproduce the effect of pattern observed experimentally. Hypotheses to interpret these results involve mechanisms at the fiber microscale including fiber fracture, cross-link breakage and fiber rearrangement, which are exacerbated by larger material deformation caused by the heterogeneous loading.

Domaines: Mécanique [physics]

Tristan Le Carre, Jean-François Blachot, Jean-Philippe Poirot-Crouvezier, Jerome Laurencin. Mechanical response of carbon paper Gas Diffusion Layer under patterned compression. International Journal of Hydrogen Energy, 2023, pp.10.1016/j.ijhydene.2023.08.104. ⟨10.1016/j.ijhydene.2023.08.104⟩. ⟨cea-04208417⟩