The effects of compression and gas diffusion layers on the performance of a PEM fuel cell

Modeling Water Management in Polymer-Electrolyte Fuel Cells

“…219,221 Experimentally, most GDLs exhibit an ideal compression value that balances the benefit from decreasing contact resistance with the penalty of impeding gas and liquid flow. 215,216,220,221 The level of trade-off observed has been seen to be dependent on current density; the greater the current density, the more severe the performance decrease with increasing pressure. 220 Another interesting consequence of GDL compression is the changing of ratios between through-plane and in-plane transport parameters and subsequent augmentation or diminishment of parameter anisotropies.…”

“…PEFC components are held together with a compressive load to ensure contact between the layers, but the additional force also affects porosity, pore-size distribution, conductivities, and contact resistances. 197,[215][216][217][218][219][220][221][222] Regions under the rib or land are expected to have decreased diffusivities and permeability in the in-plane direction and increased though-plane conductivity due to the vertical compaction of fibers. 219,221 Experimentally, most GDLs exhibit an ideal compression value that balances the benefit from decreasing contact resistance with the penalty of impeding gas and liquid flow.…”

3D analysis, modeling and simulation of transport processes in compressed fibrous microstructures, using the Lattice Boltzmann method

“…The reason is not only a local change of the topology but also a change of the inner surface S p in eq. (5).…”

“…This leads to different microstructures of the GDL in the regions under land and under channels. Lee et al [5] studied the effects of compression and GDLs on the performance of a PEFC. The non-isotropic nature of the mass transport characteristics and their strong dependency from the compression was already observed by Hussaini and Wang [6].…”

Thermal Conductivity and Contact Resistance of Compressed Gas Diffusion Layer of PEM Fuel Cell

“…When the fuel cell is assembled, a certain compression pressure must be exerted to achieve adequate contact between the components and to ensure proper gas sealing. This assembling pressure has a significant effect on fuel cell performance [20][21][22][23], mainly because of changes in the morphological and physical properties of gas diffusion layers (GDL) and catalyst layers (CL). The GDL and CL in general have highly porous structure because of the requirements set by their functions [24], and the pores of GDL are crushed to some extent when compression pressure is applied.…”