Modeling Deformation of an Electrode Surface
The deposition rate and electrode growth velocity is defined by the Current Distribution interface by the use of an Electrode Surface (applicable to exterior boundaries of an Electrolyte domain) or an Internal Electrode Surface (applicable to interior boundaries between an Electrolyte and an Electrode domain).
Use the Dissolving-Depositing species section in the Electrode Surface node to specify what species are participating in the electrode reactions, and use the Electrode Reaction subnodes to specify the reaction kinetics and stoichiometry.
An arbitrary number of dissolving-depositing species can be added on an electrode surface. The surface concentration variables of the deposited species can be used to calculate the thickness of the deposited layer, and the depositing rate is used to set the boundary velocity for the deforming geometry.
Dissolution/deposition is always assumed to occur in the normal direction to an electrode boundary, with the velocity being directed into the electrolyte domain:
(4-1)
where
v
dep, tot
is the total growth velocity, defined as the sum of the velocity contributions for all species and electrode reactions according to:
(4-2)
Where
M
i
(SI unit: kg/mol) is the molar mass and
ρ
i
(SI unit: kg/m
3
) the density of the species.
The boundary condition is implemented similarly to the Normal Mesh Velocity boundary node in the Deformed Geometry interface.