is used to define the stoichiometric coefficients, νi, with
νi being positive (
νred) for products and negative (
νox) for the reactants in a reduction reaction. The number of participating electrons,
n, is always positive.
The molar species fluxes, Ni (SI unit: mol/(m
2·s)), perpendicular to an electrode-electrolyte interface are calculated by summing all the flux contributions from the electrode reactions of index
m, according to Faraday’s laws:
where iloc, m is the local current density (SI unit: A/m
2) of the electrochemical reaction,
nm the number of participating electrons and
F (SI unit: C/mol) is the
Faraday constant. Note that
iloc, m denotes the current density perpendicular to the electrode surface.
The molar species flux, Ni, is obtained from the normal component of the molar species flux vector over the electrode-electrolyte interface:
where n is the normal vector of the boundary pointing into the domain.
where av,m (SI unit: m
2/m
3) is the specific surface area.
