A soluble lead battery benefiting from the incorporation of an ion exchange membrane to separate the positive and negative electrolyte compartments has been described. A static cell, using an electrolyte volume of 7.5 ml, was configured with and without a membrane. The use of a membrane enables the selection of electrode specific additives. In this paper, a proof of concept cell is shown with the use of Bi3+, which when added to the positive electrolyte compartment leads to a twenty-fold increase in cycle life of the cell. The bismuth ions cause a shift in the reaction mechanism and kinetics of lead dioxide dissolution during the discharge reaction.