Electrochemical characterisation of high temperature solid oxide electrolysis cell based on scandia stabilized zirconia with enhanced electrode performance

The present paper is focused on electrodes development for solid oxide electrolysis cell based on scandia doped zirconia (210 µm) electrolyte with improved performance compared to the common cells mainly based on perovskite as cathode and Ni/GDC or Ni/YSZ as anode. The influence of different operating conditions (temperature, current density, oxidant or fuel composition) on electrochemical performance is investigated. In electrolysis mode at typical operation temperature of 850°C and current density of -300mA/cm 2 the operating voltage of 1,01V is measured. The changes in polarization resistance and difference in operation between SOFC and SOEC mode is discussed based on analysis of impedance spectra of tested cells. The degradation behavior of SOEC cell is studied in detail under current density of -300mA/cm 2 and 800 °C during more than 1000h. Microstructure observations at the interfaces in both electrodes are carried out after long-term tests to understand the reasons for degradation. The technological aspects of cell production are discussed.