Simple Infiltrated Microstructure Polarization Loss Estimation (SIMPLE) Model Predictions of Today and Tomorrow's Nano-Composite SOFC Cathodes

摘要

The Simple Infiltrated Polarization Loss Estimation (SIMPLE) model was used to predict the performance of a variety of mixed ionic electron conductor (MIEC) - ion conductor (IC) Solid Oxide Fuel Cell (SOFC) nano-composite cathodes. These predictions agree with the reported values to within 70% or better (without the use of fitting parameters) at all temperatures. Systematic SIMPLE model variation of typical nano-composite cathode geometrical parameters reveals little change in cathode performance with cathode thickness and/or porosity above a critical cathode thickness. Further, SIMPLE modeling suggests that conventionally structured nano-composite cathodes with MIEC surface resistances 10 times lower than Sm_(0.5)Sr_(0.5)COO_(3-x) (SSC) and ionic conductivities 10 times higher than Ce_(0.9)Gd_(0.1)O_(1.95) (GDC) could achieve polarization resistances of 0.1 Ωcm~2 at ～450°C. Likewise, conventionally structured cathodes with 100 times and 1000 times better materials than SSC and GDC could achieve polarization resistances of 0.1 Ωcm~2 at ～375°C, and ～300°C, respectively.