Various physical methods (SEM-EDX, TEM, EXAFS, FIB-TOF-SIMS, high temperature X-ray diffraction, gas adsorption, etc.) and electrochemical methods have been used complexly for detailed analysis of ceramic materials with the perovskite structure, considered as promising alternatives to Ni-based solid oxide fuel cell (SOFC) anodes as well as solid oxide electrolysis cell (SOEC) cathodes. Comparative analysis of the data obtained by novel in situ/in operando and electrochemical methods used for characterizing the electrode materials and processes gives deeper insight into the background of various processes taking place in the materials and enables to develop new materials for various purposes. Some examples including in operando high-temperature X-ray diffraction, in operando X-ray absorption and FIB-TOF-SIMS studies will be discussed. Unit cells relaxation and interdiffusion in solid oxide fuel cells and carbon dioxide and water co-electrolysis cells will be discussed. Influence of chemical composition and preparation methods of the materials for electrolytes, electrodes and chemical barrier layers on the SOFC and SOEC characteristics will be analyzed.