in electrochemistry

Defined by the equation:
where the limiting current is assumed to be due to the diffusion species of concentration
and of diffusion coefficient.
is the charge number of the cell reaction written so that the stoichiometriccoefficient of this species is unity.
is usually taken as the geometric area of the electrode, and
is the Faraday constant.

Source:

PAC, 1974, *37*, 499*
(Electrochemical nomenclature)
* on page 513