This was the case for the interfacial capacitance reported by Baumann et al.14 (40 μF/cm2) measured for La0.6Sr0.4Co0.8Fe0.2O3−δ electrodes on YSZ electrolyte at 750 °C in air and also for a not yet interpreted capacitance (19000 μF/cm2) found in ref (13) for La0.6Sr0.4CoO3−δ on YSZ at 600 °C in 250 μbar p(O2).