Abstract: Energy conversion processes in solid oxide fuel cell (SOFC) materials are strongly affected by a nonlinear coupling between mass/charge transport, heat transport, and morphology at nanometer and micrometer length scales in a multi-phase/multi-component system. Furthermore, under continuous operation, these complex morphologies and local compositions evolve over time in response to a multitude of physical, chemical, and mechanical cues at elevated temperatures. In order to understand and predict the microstructural and thermomechanical stability of such systems, a mesoscale approach, which accurately incorporates both atomic scale information and evolving microstructures, is required. In the first part of my talk, I will present our recent work on quantifying coarsening kinetics of Ni particles in Ni-YSZ anode materials based on large-scale continuum 'phase-field' simulations, and quantify the effects of coarsening on the electrochemical performance of the system. In the second part of my talk, I will focus on the development of elastic stresses and resulting mechanical failure modes in SOFC anode materials driven by re-oxidation of Ni particles.
Short bio: Dr. Mikko Haataja is an Associate Professor in the Mechanical and Aerospace Engineering Department at Princeton University. Educated in Finland (MSc 1995, Tampere University of Technology) and Canada (PhD 2001, McGill University), his research focuses on theoretical and computational studies of phase transformation phenomena and evolving microstructures in hard and soft matter systems, such as organic semiconductor thin films, metals and alloys, ceramics, and lipid bilayer membranes. His current research is funded by the Department of Energy and the National Science Foundation.