MSE Spring Seminar Series: Professor Anton Van der Ven

Description

Understanding battery thermodynamics and kinetics with first principles statistical mechanics

Anton Van der Ven

UC Santa Barbara

Abstract: Most electrochemical processes can be modeled with powerful phenomenological theories that describe ion transport, interface reactions and mechanical responses. Phenomenological descriptions, however, rely on materials specific coefficients and free energies, which are quantities that are often difficult to measure in isolation. An alternative to an experimental approach is to predict these quantities from first principles. Since electrochemical processes are thermally activated, temperature and entropy play an important role. The prediction of materials properties, therefore, requires a statistical mechanics approach. In this talk I will describe a generalized framework with which to connect the electronic structure of crystalline solids to their equilibrium and kinetic properties at the macroscopic scale. I will illustrate how the application of first-principles statistical mechanics can generate crucial ingredients for phenomenological models of electrochemical processes, including composition dependent free energies and open circuit voltage profiles, ionic transport coefficients and chemo-mechanical response functions. The capability to predict thermodynamic and kinetic properties of electrode materials is allowing us to explore and design new battery chemistries and concepts. Electrode materials for Li, Na and Mg ion batteries undergo a series of phase transformations as a result of large changes in concentration during each charge and discharge cycle. They also exhibit highly correlated cation diffusion with important consequences for battery performance. While the mechanisms of cation diffusion and phase transformations remain poorly characterized, important insights can be generated with first-principles multi-scale approaches.

Biographical Sketch:Anton Van der Ven is professor in the Materials Department at UCSB. He obtained a PhD in Materials Science from MIT and an engineering degree in Metallurgy and Applied Materials Science from the University of Louvain, Belgium. He joined the University of Michigan as an assistant professor in 2005, following a post doc at MIT, and subsequently moved to the Materials Department at UCSB in 2013. Van der Ven’s research interests are in the area of computational materials science with a focus on developing and applying first-principles statistical mechanics methods to predict properties of materials for energy storage and high temperature structural applications. Van der Ven is the recipient of the 2022 TMS Hume-Rothery Award.