Improvement of interface between electrolyte and electrodes in solid oxide electrolysis cell

Short notice given only substantially as follows: Durability of solid oxide electrolyte supported cells was investigated under stack relevant operating conditions at -300 mA/cm² and -500 mA/cm² for high temperature steam electrolysis. To improve electrochemical and mechanical stability, especially during longterm operation, an additional layer was introduced between electrolyte and multilayer oxygen electrode based on strontium doped lanthanum manganite with additional transition metal on B-site. Different materials for this interlayer have been tested. Electrochemical testing combined with detailed microstructural analysis were carried out. The changes in polarization resistance of single cells under different operating conditions as well as during durability tests were performed and discussed on basis of analysis of impedance spectra. Microstructure observations at the interfaces in both electrodes were carried out after long-term tests to understand the reasons for degradation. The technological aspects of cell production are discussed.