MMAE Seminar: “Fast Charging Technology of Li-ion Batteries: Graphite Particle Effects and Aging Mechanisms,” Mei Luo

Headshot of Mei Luo, postdoctoral researcher in the CSE department at Argonne National LaboratoryThe Department of Mechanical, Materials, and Aerospace Engineering presents its seminar series featuring Mei Luo, postdoctoral researcher in the CSE department at Argonne National Laboratory, who will give a presentation on “Fast Charging Technology of Li-ion Batteries: Graphite Particle Effects and Aging Mechanisms.” This seminar will take place on Wednesday, November 13, from 12:45–1:45 p.m. in room 104 of the Rettaliata Engineering Center.

Abstract

As electric vehicles (EVs) gain popularity, the need for extreme fast charging (≤15 minutes) of lithium-ion batteries becomes increasingly critical. However, significant capacity fade and safety issues—primarily due to lithium plating—pose major barriers to its widespread adoption. Here, we will explore the fast-charging capabilities of Li-ion batteries, with a focus on graphite anode materials and their role in mitigating lithium plating. We will first discuss the effect of graphite particle size on fast charging performance. Our study reveals that smaller graphite particles exhibit superior performance, faster charging rates, and less lithium plating compared to larger particles. Using ultra-thin graphite electrodes, we analyzed the fast-charging performance of graphite at the particle level and incorporated modeling work to identify that particle-level diffusion is the dominant mechanism contributing to lithium plating at high charging rates, rather than interfacial reactions. We will also delve into the aging mechanisms of lithium-ion batteries under various charging conditions. Our study of NMC/graphite pouch cells charged at different rates (from 0.5C to 6C) highlights the significant impact of fast charging on battery longevity. Advanced post-mortem analyses revealed that while NMC cathodes experienced some pulverization, it was the graphite anodes that faced the most severe degradation under fast charging—specifically due to increased lithium plating and the formation of a LiF-rich solid electrolyte interphase (SEI). Valuable insights would be provided into electrode designs and managing degradation from fast charging, ultimately contributing to the development of safer and longer-lasting lithium-ion batteries for EV applications.

Biography

Mei Luo is a postdoctoral researcher in the CSE department at Argonne National Laboratory, having earned her Ph.D. in material science and engineering from Illinois Tech. With more than eight years of expertise in energy storage technologies, Luo specializes in advanced battery systems, including Li-ion, Na-ion, and Li-S batteries. Her research primarily focuses on advancing Li-ion batteries, particularly in the areas of silicon and graphite anodes, as well as fast charging technology. Luo has extensive experience in material synthesis, characterization, battery fabrication, evaluation, and analysis, with specialized skills in three-electrode battery systems, full cell design, and degradation mechanisms, etc. Luo is highly proficient in experimental design, data analysis, and Python scripts, which she utilizes to drive research efficiency. Luo’s collaborative projects with various renowned institutions along with industry partners, have broadened her research scope and enhanced her interdisciplinary expertise, emphasizing her ability to excel in diverse research teams. Luo is dedicated to advancing battery technology and consistently pursues excellence in scientific research.