ME Faculty Seminar Series: Neil Dasgupta

Abstract: The rapidly growing EV market is increasing the demand for fast-charging (<15 min) of high-energy-density Li-ion batteries. However, state-of-art Li-ion batteries with thick graphite electrodes suffer from Li plating when charged at 4C rates. Therefore, to inform mitigation strategies for Li plating under fast-charging conditions, there is a need to improve our fundamental understanding of the Li plating process. Additionally, new manufacturing approaches are needed to overcome these energy/power tradeoffs in LIBs

In this talk, I will first describe our recent efforts in the application of&nbsp;in situ&nbsp;analysis during fast charging to gain a mechanistic understanding of the Li plating process.&nbsp;&nbsp;Equipped with this fundamental knowledge, I will introduce three strategies to enable fast charging LIBs, using industrially-relevant pouch cells fabricated at the UM Battery Lab.&nbsp;&nbsp;In the first strategy, vertical channels are introduced into post-calendared electrodesusing laser ablation patterning. The resulting 3-D anode architecture consists of a hexagonal close-packed array of vertical channels that serve as linear pathways for rapid ionic diffusion through the electrode thickness.&nbsp;&nbsp;In the second strategy, the energy/power tradeoffs in carbonaceous anode materials are overcome by forming hybrid blends of graphite and hard carbon. This allows for a balance between the higher energy density ofgraphite with the faster rate performance of hard carbon. In the third strategy, we demonstrate the potential to eliminate Li plating and enabling 4C fast charging purely through interfacial control.&nbsp;&nbsp;This is achieved by coating the surface of graphite with a solid-state electrolyte material using Atomic Layer Deposition (ALD). Finally, I will describe remaining challenges towards commercialization, including scale-up, cost reduction, and infrastructural considerations.

Bio

Neil Dasgupta is an Associate Professor in the Departments of Mechanical Engineering and Materials Science &amp; Engineering at the University of Michigan. He earned his Ph.D. from Stanford University in 2011. Prior to joining University of Michigan in 2014, he was a postdoctoral fellow at the Universityof California, Berkeley. He is a recipient of the NSF CAREER award, DARPA Young Faculty Award (YFA), AFOSR Young Investigator Award (YIP), 3M Non-Tenured Faculty Award, and the ECS Toyota Young Investigator Fellowship. His research focuses on the intersection of energy conversion, materials chemistry, and manufacturing.