Cyclic voltammetry, in conjunction with the chromatographic analysis of the anode product, has been used to elucidate the reactions occurring during the electrolysis of lithium carbonate-lithium chloride melts. At a carbonate ion concentration of 0.033 mole fraction the peak anodic current densities were 3100 A m(-2) on vitreous carbon and 6900 A m(-2) on graphite with the product being carbon dioxide. The cathodic reduction of carbonate at low concentrations was found to occur at -1.0 V to -1.2 V vs a Ag/Ag(I) reference electrode which is 1.2 V less negative than the potential at which lithium ions were reduced. Voltammetric studies of the reduction of the carbonate ion indicated that the reaction mechanism involved an irreversible charge transfer.