Modeling of the dynamics of metal deposition inside a flow-through porous electrode with low initial conductivity

With the help of the previously developed dynamic model of the equipotential porous electrode (PE) supplemented with the unit to calculate the local conductivity of the solid phase, the effect of solution flow direction and rate on the process of metal electrodeposition on the porous matrix with low initial conductivity is investigated. It is established that in comparison with the equipotential PE the noticeable differences in the final mass of the deposit and uniformity of its distribution are observed only in the case of rather low conductivity of the metal deposit (⩽100 Ω−1 cm−1), the direction and scale of these differences being dependent on the rate and type of solution feed into the PE. For high flow rates, the effect is positive and weakly dependent on the direction of solution feed. To the contrary, in the region of medium and low solution flow rates, the effect is negative for the back solution feed and essentially positive for the front one. In order to explain the observed regularities, we consider the features of changes in the distribution of polarization, metal ion concentration and local conductivity of the solid phase during the metal deposition process.