MSE PhD Final Defense: Madison Morey

MSE PhD Final Defense: Madison Morey

TITLE: Understanding Surface Characteristics And Their Effects On Dendrite Growth At The Anode-Electrolyte Interface Of Lithium Batteries

ADVISOR: Emily Ryan, ME

COMMITTEE: Sean Lubner, ME (Chair); Joerg Werner, ME; Sheryl Grace, ME; Jianlin Li Argonne National Lab

ABSTRACT: A comprehensive understanding of the morphological evolution of deposited lithium (Li) is a primary challenge in the commercialization of Li-metal batteries. In this dissertation, a computational model is developed using the smoothed particle hydrodynamic method to simulate the morphological evolution of metallic electrodeposition. The model tracks mass transport in a binary electrolyte via the Nernst-Planck equation, a spatially and temporally varying electric field through the electrostatic Poisson equation, nucleation via a nucleation rate derived from classical nucleation theory, and utilizes an extended Butler-Volmer equation to capture the electrochemical reactions at the anode-electrolyte interface. The model is applied to study dendrite growth in Li metal batteries, which pose safety concerns and are detrimental to battery performance. Li deposition is difficult to study experimentally due to the embedded nature of the anode-electrolyte interface, while computational modeling allows for the isolation of the interface and physical phenomena to study their individual effects on dendrite growth. The model effectively captures the effects of changes in the operation and design parameters of the system allowing for a better understanding of the interplay between complex physical phenomena. In particular, the research focuses on the impact that varying surface characteristics have on the stability of the anode, including patterned anode surfaces for guided Li deposition, interfacial energy, anode defects, and the solid electrolyte interphase layer. Additionally, the model is applied to study how the manufacturing and fabrication of the anode-electrolyte interface and electrolyte impacts the morphology of deposited Li and how operational parameters, such as varying applied potentials and altered charging protocols, either exacerbate or mitigate dendrite growth. Finally, the computational studies presented throughout this dissertation provide suggestions for improved battery designs and can aid in the suppression of dendritic Li morphologies allowing for more stable interfaces and dependable Li batteries.