Spatiotemporal Heterogeneities in Battery Electrodes

Speaker: Peng Bai, Washington University in St. Louis

Abstract
Batteries are ubiquitous in our daily life, so are the potential safety risks, as already witnessed by the fast development of portable electronic devices and electric cars. Designing safe batteries has been very challenging as the spatiotemporal heterogeneities already discovered in experimental systems have not been translated into rigorous mathematical formulas for practical implementation. In this seminar, we will see how the total current applied to the battery electrodes, both the phase-forming lithium metal anode and phase-transforming intercalation porous electrode, will inevitably get localized to surpass the safety limit by several orders of magnitude. The extreme local electrochemical dynamics, under the disguise of the safe total current, are responsible for the unexpected failures of batteries. While continuum-level mathematical models we developed can accurately explain the evolution of these heterogeneities, new methods of artificial intelligence may eventually help identify the fundamental reasons and multiscale characteristics of their initiation at the interface exchanging energy and materials.

Bio
Professor Bai obtained his Bachelor’s degree in Automotive Engineering and PhD degree in Mechanical Engineering from Tsinghua University in 2007 and 2012, respectively. He continued his research in the Department of Chemical Engineering at MIT as a postdoctoral associate and research scientist, prior to joining Washington University in St. Louis as a tenure-track Assistant Professor in 2017. With his expertise in physics-based mathematical modeling and analytical electrochemistry, Professor Bai has published original research in scientific journals including Science, Nature Communications, Energy & Environmental Science, Joule, Nano Letters, etc. His unique contributions earned him the Oronzio and Niccolò De Nora Foundation Young Author Prize from the International Society of Electrochemistry (ISE) in 2014, and the ISE Prize for Electrochemical Materials Science in 2018.