Electrodeposition of metal inside the porous electrode under periodic reversal of solution flow

With the help of previously developed dynamic model of porous electrode (PE) with high initial conductivity, we investigate the effect of flow rate (0.05-10 cm/s) and direction of solution flow (rear and front feed, as well as flow reversal) on the dynamics of metal electrodeposition inside the porous matrix. It is established that with an increase in flow rate the final mass of metal m_k inside the PE increases by a factor of 2-3; this dependence is nonmonotonous and has a maximum in the region of medium flow rates, which is most clearly exhibited for the rear feed (additional increase in % by a factor of 1.5-2). The m_k values are in good correlation with the measure of metal distribution uniformity: the more uniform is distribution of the deposit inside the PE, the larger is m_k, for other conditions being the same. Within the area of high and very low flow rate, m_k is independent of the flow direction. In the former case, the profiles of metal distribution almost coincide, while in the latter one they are mirror-opposite. The highest effect of flow direction is observed for medium flow rates. Because of this, under these conditions it is reasonable to apply flow reversal in order to improve the uniformity of metal distribution and its final mass (an increase in m_k by 20-30%). For high flow rate, reversal does not give effect, while for low rates maximal relative effect is observed (a 2-fold increase); however, absolute m_k values are not large.