A 3D Simulation of DC-Biased Electrochemical Impedance of Solid Oxide Electrolysis Cell: Effects of Delamination

Abstract

Solid oxide electrolysis cell (SOEC) is one of the best candidates for hydrogen production with zero carbon footprint, but cell degradation limits its implementation for long-term application. In this study, a three-dimensional (3D) button cell configuration model is used to study the oxygen electrode (OE) delamination, which is the major cause for the cell degradation during polarization life cycle. A composite lanthanum strontium cobalt ferrite (LSCF) and gadolinium doped ceria (GDC) is used as OE material. From the initial observation by solving for species transport equations for different crack propagation, it was found that cell degradation was largely dependent on relative area cracked at OE/electrolyte (EL) interface and independent of direction or shape of crack propagation. Electrochemical impedance spectroscopy (EIS) from physics-based model under DC bias is implemented to examine closely the electrochemical properties variation with aid of experiment measurement.