When used as ceramic membranes for the electrically driven separation of oxygen from air, BIMEVOX materials allow the production of high oxygen fluxes at moderate temperature, 300–600°C. However, 18O/16O Isotope Exchange Depth Profile Technique revealed low kinetics of oxygen transfer at the surface of these ceramics when studied under equilibrium. These kinetics were considerably enhanced when a current was applied. The same membranes were characterized under working conditions using X-ray synchrotron and neutron radiations. Their dynamical transformation under bias was confirmed and explained by a slight reduction of the BIMEVOX electrolyte under working conditions.