The electrolyte supported cells with low area specific resistance (ASR<0.34 Ohm cm²) have been tested for long-term, thermal and redox stability in ceramic housing. It has been shown that the cells with optimized anode microstructure have degradation <0,1 % / 1000h and no measurable resistance change in the range of mistake of used method after ten thermal and redox cycles. The small fluctuation of contact resistance between anode and current collector has been observed especially during cycling experiments. The redox cycles lead to the largest fluctuation of ASR values during cycling due to direct influence on the bonds between anode and current collector.

Recently Kerafol's alliance with H.C. Starck and the commercial availability of the jointly developed high - output cells with scandium doped zirconia electrolytes was announced. Together the companies are able to provide cells possessing extraordinary performance and long term stability. The combined production facilities meet the increased demand of SOFC stack and system manufacturers. Currently the installation of test benches for MEA characterization is being prepared for quality assurance as well as for development. In addition to cell performance enhancements the emerging topic of electrolysis with solid oxide electrolysis cells (SOEC) will be examined. Because of the fluctuating availability of renewable energy the electrolysis mode of SOFCs to save energy in form of hydrogen during an overproduction and the reverse power generation during periods without wind or sun is of high interest. The first step in a new project examines the feasibility of a SOEC. The next steps include the development of reliable cells with regard to robustness and long term stability. In this paper the status quo of electrolyte supported cells as well as the development project dealing with SOEC at Kerafol is summarized. Additionally the optimization of tape cast, custom-fit glass sealants obtainable from Kerafol for both SOFC and SOEC applications is described. The efforts are focused upon quality improvement, cost reduction and industrial scale manufacturing of sealants.