A physically-based modelling to predict the cyclic voltammetry response of LSCF-type electrodes: Impact of the Ohmic Losses and Microstructure

Two numerical models have been developed to simulate the Cyclic Voltammetry (CV) response of Lanthanum Strontium Cobalt Ferrite (LSCF) porous electrode at high temperature. The first one (model-I) takes into account solid-state diffusion in LSCF coupled with a global reaction oxygen exchange while second (model-II) is based on detailed elementary description mechanism. relevance model-II predict voltammograms has checked experimental data obtained different operating temperatures and imposed scan rates. CV quasi-dense electrodes studied two discussed frame zone diagram method. It shown that peaks are due transient change stoichiometry LSCF. As this evolution mainly governed by material exchange, it established model-I can provide satisfactory approximation curves if rate constant kchem determined far from equilibrium. also strongly distorted Ohmic losses making their interpretation impossible practice, under classical conditions solid oxide cells. To overcome limitation, methodology modelling approach proposed remove hence reveal voltammetry peaks. Finally, impact decomposition estimated model-II. surface passivation decrease chemical diffusivity substantially affect shape voltammograms.