Performance & Reliability of solid oxide fuel cell materials: A modeling perspective

Abstract

The design, selection and manufacture of solid oxide fuel cell  (SOFC) materials is intimately dependent upon numerous materials phenomena, such as, oxygen transport through electrolyte/electrodes, inter-diffusion of cations in the constituent layers of a SOFC, interface reactions, and mechanical stresses induced due to thermal / compositional self-strains. A detailed examination of these effects requires modeling approaches on varied length/time scales. We illustrate this via two examples: (1) A multi-scale modeling approach, combining density functional theory methods and kinetic Monte Carlo methods to study oxygen diffusion in yttria stabilized zirconia (YSZ), the commonly used electrolyte material, and,  (2) A coupled transport-mechanics model to study stress (and self-strain) evolution in a SOFC electrolyte during operation. Simulation results in both examples match successfully with experimentally observed behavior and measured data. We discuss the implications of these results for SOFC material design and manufacture.

Biography

Ram Krishnamurthy is currently a Senior Research Engineer at the Technology and Solutions Division, Caterpillar Inc. He obtained a Ph. D in engineering from Brown University in 2002. He also holds Master of Science degrees in engineering and applied mathematics, respectively, from Brown University. After obtaining his Ph.D. degree, he pursued postdoctoral research in the Department of Mechanical and Aerospace Engineering at Princeton University, before moving to his current position in Caterpillar. His research interests lie in developing theory and modeling methods to explore the interplay between transport, mechanics, chemistry and microstructure evolution in materials processing and phenomena, with particular interest in thin film coatings, advanced ceramics and energy-related applications.