A physics-based model is presented to simulate the electrochemical behavior of mixed ion and electron conducting (MIEC) cathodes for intermediate-temperature solid oxide fuel cells. Analytic solutions for both transient and impedance models based on a finite length cylinder are derived. These solutions are compared to their infinite length counterparts. The impedance solution is also compared to experimental electrochemical impedance spectroscopy data obtained from both a traditional well-established La0.6Sr0.4Co0.2Fe0.8O3-delta (LSCF) cathode and a new SrCo0.9Nb0.1O3-delta (SCN) porous cathode. The impedance simulations agree well with the experimental values, demonstrating that the new models can be used to extract electro-kinetic parameters of MIEC SOFC cathodes. (C) The Author(s) 2016. Published by ECS. All rights reserved.