Deposit roughness can lead to increased product impu-rity levels and short-circuiting. Rough deposits can trap solutionand particles into the deposit, thereby increasing product impu-rity levels, which increases product rejection rates and productivity[28–30]. In addition, rough deposits are associated with unde-sirable localized growth. If local growth feature size exceeds theseparation between cathodes and anodes, short-circuiting occurs.Short-circuiting creates current inefficiency and wastes power.Thus, electrodeposit smoothing using additives and mass transportcontrol is important to sustainable electrometallurgy.