Measurements are reported of the time dependence of the current during electrochemical oxidation and reduction at a fixed voltage of single crystals and ceramic samples of La2CuO4+d. Staging peaks in neutron measurements of the single crystals together with the electrochemical measurements and magnetization measurements confirm that stage n=6 corresponds to d=0.055 +/- 0.05, the high-d side of the oxygen-rich–oxygen-poor miscibility gap. Furthermore, stage n=4 occurs at a value of d consistent with d { n^(-1). For ceramic samples it is shown that two different superconducting compounds are formed depending on the oxidation voltage used.