The Porous Electrode node sets up charge balances for the electrode and the pore electrolyte in a porous electrode. Note that the node should be used for porous domains that conduct current in both an electrolyte and an electrode phase. For the case of domains that do not contain a pore electrolyte — for instance, the gas diffusion layer (GDL) in a PEMFC electrode — use an
Electrode node instead.
Use Porous Electrode Reaction subnodes to define the charge transfer reactions that occur on the interface between the electrolyte and electrode phases within the porous electrode. For the Secondary Current Distribution interface, the
Porous Matrix Double Layer Capacitance subnode is also available.
The conductivities are taken From material by default. From the respective material list you may any material in the model, if present. By default they are set to the
Domain material (which is the material applied to the active domain in the
Materials node).
You may use the Effective conductivity correction factors to account for the lowered effective conductivities of the electrode and electrolyte phases due to the lower volume fractions of each phase, and the tortuosity of the porous matrix.
The Electrode volume fraction is used to calculate the effective electrical conductivity of the porous matrix when the correction factor is set to
Bruggeman or
Tortuosity. Additionally, it
is used in calculating the active specific surface area of the porous matrix when
Particle-based area option is selected in the child nodes.
