Analysis of ESC Performance for Long-Term Operation with Different Fuel Utilization in SOFC/SOEC and in Reversible Cycling Mode

The stability of cell resistance during operation at high current density is one of the enablers for success of high temperature electrolysis technology. Both the electrochemical performance and lifetime can be considerably enhanced by improving the electrodes interfaces as well as electrodes microstructures. The present paper focusses on the detailed analysis and discussion of degradation phenomena of developed ESC cells during galvanostatic steady-state SOFC and reversible SOFC/SOEC cycling operation. The changes in polarisation resistance of high power density electrolyte supported cells investigated over a wide range of operating conditions (SOFC/SOEC) such as operating temperature (750-850°C) and current density are presented und discussed on basis of analysis of impedance spectra. The results indicate that durability and electrochemical performance of developed cells are greatly enhanced by the optimization of electrode microstructure and contacting layers.