Electrochemical energy conversion and storage using efficient solid oxide cells would enable the transition to a fossil-free society. However, a reduction in costs and an increase in durability of the technology is first required. In this project we will research and employ novel operational reduction/oxidation (redox) procedures for periodic reactivation of the cell performance. Highly promising preliminary data show that such treatment can significantly improve the electrode durability. Suitable electrodes will be developed and advanced operando surface-sensitive spectroscopy will be used to grasp the science of the phenomenon. The understanding of the redox reactivation will lead to an optimized employment and in turn to drastically improved durability of cells. This will make the technology cheaper than the alternatives, and enable efficient and cheap energy storage and conversion in Denmark as well as abroad.