Current Density Distribution in a Proton Exchange Membrane Fuel Cell
The model shows the current density distribution in the cathode of a PEMFC using a serpentine gas channel configuration.The block-shaped subdomain represents the porous cathode, where transport is modeled by diffusion only, using Maxwell-Stefan diffusivities. The electrode reaction, which couples the concentration of oxygen and the electrical potential, is treated as a boundary at the position of the active layer at the bottom surface of the domain.
This study exemplifies the use of modeling in the design of experiments and fuel cell prototypes. The model is based on simple charge and mass balances in the gas diffusion electrodes and the electrolyte in the fuel cell.
Despite its simplicity, the model is able to account for the transport resistance as well as the activation overvoltage. This implies that it can be used to optimize the electrode structure in order to minimize concentration and activation polarization.
The curved channel is meshed using brick elements while the porous structure is modelled using prisms. The model also uses identity boundary conditions to connect the different types of mesh.
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Boundary plot showing the weight fraction of water. |
Engineering Fields
- Momentum Transfer & CFD
- Mass Transfer
- Electrochemical Engineering
Application Areas
- Electrochemistry
- Chemical Reaction Engineering