Contact resistance between gas diffusion layer and catalyst layer of PEM fuel cell

2008 ◽  
Vol 10 (1) ◽  
pp. 47-51 ◽  
Author(s):  
Iwao Nitta ◽  
Olli Himanen ◽  
Mikko Mikkola
Keyword(s):  
Fuel Cell ◽  
Contact Resistance ◽  
Diffusion Layer ◽  
Catalyst Layer ◽  
Gas Diffusion Layer ◽  
Pem Fuel Cell ◽  
Gas Diffusion

scholarly journals Analytical Impedance of Oxygen Transport in the Channel and Gas Diffusion Layer of a PEM Fuel Cell

2021 ◽  
Author(s):  
Andrei Kulikovsky
Keyword(s):  
Fuel Cell ◽  
Diffusion Layer ◽  
Oxygen Transport ◽  
Analytical Formula ◽  
Catalyst Layer ◽  
Gas Diffusion Layer ◽  
Pem Fuel Cell ◽  
Gas Diffusion ◽  
Nyquist Plot ◽  
Current Conservation

Abstract An analytical model for impedance of oxygen transport in the gas--diffusion layer (GDL) and cathode channel of a PEM fuel cell was developed. The model is based on transient oxygen mass conservation equations coupled to the proton current conservation equation in the catalyst layer. An analytical formula for the ``GDL+channel'' impedance was derived assuming that the oxygen and proton transport in the cathode catalyst layer (CCL) are fast. In the Nyquist plot, the resulting impedance consisted of two arcs describing oxygen transport in the air channel (low--frequency arc) and in the GDL. The characteristic frequency of GDL arc depends on the CCL thickness: large CCL thickness strongly lowers this frequency. At small CCL thickness, the high--frequency feature on the arc shape forms. This effect is important for identification of peaks in distribution of relaxation times spectra of low--Pt PEMFCs.

Effect of Porosity Gradient in Gas Diffusion Layer on Cell Performance With Thin-Film Agglomerate Model in Cathode Catalyst Layer of a PEM Fuel Cell

2011 ◽  
Author(s):  
Chun-I Lee ◽  
Shiqah-Ping Jung ◽  
Kan-Lin Hsueh ◽  
Chi-Chang Chen ◽  
Wen-Chen Chang
Keyword(s):  
Thin Film ◽  
Fuel Cell ◽  
Diffusion Layer ◽  
Liquid Water ◽  
Water Saturation ◽  
Catalyst Layer ◽  
Gas Diffusion Layer ◽  
Pem Fuel Cell ◽  
Gas Diffusion ◽  
Water Flooding

A one-dimensional, steady-state, two-phase, isothermal numerical simulations were performed to investigate the effect on cell performance of a PEM fuel cell under non-uniform porosity of gas diffusion layer. In the simulation, the non-uniform porosity of gas diffusion layer was taken into account to analyze the transport phenomena of water flooding and mass transport in the gas diffusion layer. The porosity of the gas diffusion layer is treated as a linear function. Furthermore, the structure of the catalyst layer is considered to be a cylindrical thin-film agglomerate. Regarding the distribution analysis of liquid water saturation, oxygen concentration and water concentration depend on the porosity of gas diffusion layer. In the simulation, the εCG and εGC represent the porosity of the interfaces between the channel and gas diffusion layer and the gas diffusion layer and the catalyst layer, respectively. The simulation results indicate that when the (εCG, εGC) = (0.8, 0.4), higher liquid water saturation appears in the gas diffusion layer and the catalyst layer. On the contrary, when the (εCG, εGC) = (0.4, 0.4), lower liquid water saturation appears. Once the liquid water produced by the electrochemical reaction and condensate of vapor water may accumulate in the open pores of the gas diffusion layer and reduced the oxygen transport to the catalyst sites. This research attempts to use a thin-film agglomerate model, which analyze the significant transport phenomena of water flooding and mass transport under linear porosity gradient of gas diffusion layer in the cathode of a PEM fuel cell.

Lattice Boltzmann Modeling of Water Cumulation at the Gas Channel-Gas Diffusion Layer Interface in PEM Fuel Cells

2014 ◽  
Author(s):  
Dario Maggiolo ◽  
Andrea Marion ◽  
Massimo Guarnieri
Keyword(s):  
Fuel Cell ◽  
Diffusion Layer ◽  
Lattice Boltzmann ◽  
Gas Diffusion Layer ◽  
Pem Fuel Cell ◽  
Pem Fuel Cells ◽  
Gas Diffusion ◽  
Vapor Condensation ◽  
Relative Height ◽  
Gas Channel

Several experiments have proved that water in liquid phase can be present at the anode of a PEM fuel cell due to vapor condensation resulting in mass transport losses. Nevertheless, it is not yet well understood where exactly water tends to cumulate and how the design of the gas channel (GC) and gas diffusion layer (GDL) could be improved to limit water cumulation. In the present work a three-dimensional lattice Boltzmann based model is implemented in order to simulate the water cumulation at the GC-GDL interface at the anode of a PEM fuel cell. The numerical model incorporates the H2-H2O mixture equation of state and spontaneously simulates phase separation phenomena. Different simulations are carried out varying pressure gradient, pore size and relative height of the GDL. Results reveal that, once saturation conditions are reached, water tends to cumulate in two main regions: the upper and side walls of the GC and the GC-GDL interface, resulting in a limitation of the reactant diffusion from the GC to the GDL. Interestingly, the cumulation of liquid water at the interface is found to diminish as the relative height of the GDL increases.

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