Packed bed electrodes, made of stacked screens, have been used as cathodes for the removal of lead ions from flowing alkaline electrolytes. We consider the coulombic efficiency xi = i(Pb)(i(Pb) + i(H)), where i(Pb) and i(H) are, respectively, the lead deposition and hydrogen evolution currents, and the collection efficiency given by psi = iL(exp.)/nF nu c degrees, where i(L(exp.)) is the geometric limiting current for lead deposition, nu is the electrolyte flow rate, and c degrees is the feed concentration of lead ions. Two regions are defined in the current-potential relations, depending on whether hydrogen evolution does, or does not, contribute to the measured current, corresponding to xi less than, or equal to, 100%, respectively. The geometric limiting current, i(L(exp.)), increases with increase of nu, electrode thickness (L), or specific surface area (S), and with decrease of the viscosity of the electrolyte (mu) The collection efficiency (psi) increases as nu or mu decreases and L and/or S increases. Operating die cell at higher flow rates increases the overall coulombic efficiency, over a broader range of cell currents. It also increases the geometric limiting current although it decreases the collection efficiency.