Grey-box Modeling of Reversible Solid Oxide Cell Stack’s Electrical Dynamics Based on Electrochemical Impedance Spectroscopy

This paper aims to design a lumped-capacity model of a reversible solid oxide cell stack for hydrogen electrolysis. The lumped-capacity model needs to have an adequate representation of the electrical dynamics over a wide operating range and a model structure suitable for the design of a physical emulator. The grey-box model is based on data obtained by electrochemical impedance spectroscopy conducted on a commercial solid oxide cell stack for four different gas compositions at six aging stages. In addition, a comparison of the experimental and simulated voltage response of the reversible solid oxide cell stack in cyclic reversible operation mode was conducted at different aging levels of the stack.