In this work, the effect of purge gas supplied to the cell anode on the degradation of solid oxide electrolysis cells was studied. Three cells have been operated at 700 °C, -0.5 A/cm2 with 10% H2 + 90% H2O supplied to the fuel electrode compartment (cathode). The oxygen electrode was supplied either with air, CO2 or no gas. Detailed electrochemical characterization measurements such as current-voltage curves and electrochemical impedance spectra were obtained to monitor the cell degradation with time. The results show similar voltage after 1000 hr for the cells operated with air (1336 mV) and no purge gas (1370 mV), but a significantly higher voltage (1605 mV) for the CO2 purge. This cannot be explained by Nernst effects. Analysis of the cell impedance reveals that the oxygen electrode impedance is increased in CO2. The electrode performance partly recovers when terminating the CO2 purge.
|Number of pages||9|
|Publication status||Published - 2021|
|Event||17th International Symposium on Solid Oxide Fuel Cells - Stockholm, Sweden|
Duration: 18 Jul 2021 → 23 Jul 2021
Conference number: 17
|Conference||17th International Symposium on Solid Oxide Fuel Cells|
|Period||18/07/2021 → 23/07/2021|