Particle Diffusivity Functions

ionworkspipeline.direct_entries.arrhenius_particle_diffusivity(electrode: str, direction: str = '', phase: str = '')

Returns a DirectEntry object with a reference diffusivity multiplied by arrhenius temperature dependence for the negative or positive electrode. The reference diffusivity can be a constant, or a function of the stoichiometry.

The diffusivity is of the form:

\[D = D_{ref}(sto) \exp(E / R (1 / T_{ref} - 1 / T))\]

where \(D_{ref}\) is the reference diffusivity, \(E\) is the activation energy, \(R\) is the gas constant, \(T_{ref}\) is the reference temperature, and \(T\) is the temperature.

This leaves the following parameters to be defined (e.g. by fitting to data):

  • Negative/Positive particle reference diffusivity [m2.s-1] ($D_{ref}$)

  • Negative/Positive particle diffusivity activation energy [J.mol-1] ($E$)

Parameters

electrodestr

The electrode to return the diffusivity for. Must be “negative” or “positive”.

directionstr, optional

The direction of the exchange-current density. Can be “lithiation” or “delithiation” or an empty string.

phasestr, optional

Specifies the phase (“primary” or “secondary”) for composite electrode models. Default is an empty string.