Theoretical Analysis of Current Distribution in Porous Electrodes

Abstract

General equations describing the behavior of porous electrodes are developed. These equations are used to determine the initial and the steady‐state conditions in one‐dimensional porous electrodes of uniform geometry and polarization parameters. In particular, it is shown that the current and reaction distributions in the depth of the electrode are strongly influenced by the type of activation polarization and by mass transport of the reacting ionic species, in addition to the effective conductivities of the two phases. It is found that a linear approximation to a Tafel curve leads to an inadequate description of actual behavior when the reaction is distributed nonuniformly in the depth of the electrode.