Dr. Stefanopoulou, Anna G.
Department of Mechanical Engineering
University of Michigan
Seminar Information
Battery degradation is at the crux of the total cost of ownership and the lifetime GHG abatement of Electric Vehicles (EVs) and Battery Energy System Storage (BESS). Currently, the battery State of Health (SOH) is quantified by capacity (cyclable energy) and cell resistance (power capability).
The challenge in predicting Remaining Useful Life (RUL) depends on determining the battery degradation mechanisms, which is harder than estimating SOH, and can be achieved by measuring and interpreting the reversible and irreversible expansion of batteries. The mechanisms that make batteries age are rust-like (SEI) film growth in electrode particles that starts at manufacturing and continues with time. Additional degradation mechanisms are anode plating and particle fracture, which cause cell thickness growth. An abnormal swelling from gas accumulation in cells during elevated temperatures or abusive conditions (internal or external short) can also determine the battery's State of Safety (SOS).
Forecasting RUL and SOS can inform decisions regarding vehicle resale value, vehicle-to-grid benefits, repurposing, or recycling. Predicting RUL is thus critical for maximizing batteries' benefit, protecting aged battery assets, stretching their lives, and creating a circular battery economy.
In the last part of this talk, Stefanopoulou will discuss how to apply technical skills and knowledge from traditional (i.e., fossil fuel) engine development to management systems for alternative fuel engines, batteries, and fuel cells.
Anna G. Stefanopoulou is the William Clay Ford Professor of Technology at the University of Michigan. She served as 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 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 US National Academy committees (2015 and 2020), which were formed upon the request of the US 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.