2024 Nyquist Lecture: Battery State of Health Estimation from Manufacturing to End of Life

Abstract- This lecture will summarize efforts in building a community to support scientifically a global need for on-board diagnostics and state of health (SOH) estimation in batteries using physics-based models. Due to the importance of battery degradation throughout use and storage, numerous legislative actions are underway for battery durability and SOH estimation accuracy. Beyond SOH, we point to the challenges in predicting remaining useful life for the resale of battery electric vehicles or stretching their utilization by supporting home or grid loads when parked. We show how these challenges are addressed by using physics-based models that allow the estimation of the states of the underlying degradation mechanisms.

We then show how these model-based estimation techniques can improve battery manufacturing. The physics-based models are also extendable to capture transitions to abnormal behavior, such as inhomogeneities or gas evolution, allowing us to detect imminent faults and their fate. We will conclude with highlights from efforts with community college faculty to co-develop educational material for batteries and thus help with the transition to BEV manufacturing.

Bio- Anna G. Stefanopoulou is the William Clay Ford Professor of Technology at the University of Michigan. She was the Director of the Automotive Research Center, a multi-university U.S. Army Center of Excellence of Ground Vehicles, and the Michigan Energy Institute. She was also an assistant professor at the University of California, Santa Barbara, and a technical specialist at Ford Motor Company.

She has been recognized as a Fellow of the ASME (08), IEEE (09), and SAE (18). Her recent awards are the 2019 AACC Control Engineering Practice Award (“for the modeling, analysis, and control of advanced vehicle powertrain systems”), the 2018 ASME Charles Stark Draper Innovative Practice Award (for advancing engine, fuel cell, and battery management), and the 2017 IEEE Control System Technology award (for advanced battery management system accounting for electro-thermo-mechanical phenomena).

She has served on two U.S. National Academy committees (2015 and 2020), which were formed upon the request of the U.S. Congress to report on vehicle fuel economy standards and the transition to electrification. She has advised and mentored more than 50 Ph.D. students and co-authored with them a book, 25 U.S. patents, and more than 400 publications (seven of which have received awards) on the estimation and control of engines, fuel cells, and batteries.

***The event will take place in person. The location for in-person attendance will be in room 1303 EECS. There will be no zoom or recording for this seminar***