Origin and quantitative analysis of the constant phase element of a platinum SOFC cathode using the state-space model

The characteristics of a solid oxide fuel cell cathode are investigated using a combination of scanning electron microscopy, electrochemical impedance spectroscopy and simulations using the state-space model (SSM). We successfully explain the shape of the impedance spectrum at several temperatures, determine kinetic parameters, measure the triple phase boundary length and deduce its width. Finally a quantitative analysis of the constant phase element using surface roughness and energy activation distribution is presented.