Visualizing 3D Morphologies and Spatial Heterogeneities of Li after Fast- Charging via In-situ Neutron Tomography

Published

March 22, 2024

Author(s)

Maha Yusuf, Anders Kaestner, Markus Wied, Jacob LaManna, Nghia Vo, Alison Dunlop, Andrew Jansen, Bryant Polzin, Stephen Trask, Markus Strobl, Vanessa Wood, Michael Toney, Johanna Weker

Abstract

Mechanistic understanding of Li plating is imperative to developing fast-charging batteries for sustainable electric vehicles. Here, we report in-situ 3D characterization of the morphology and spatial heterogeneities of Li plating using neutron micro-computed tomography with a spatial resolution of 10-15 microns. Two batteries are imaged in charged and discharged states after: (1) 4 cycles of 1C and (2) 6 cycles of 6C charging. Neutron images show that Li plates at and around the edge of graphite, indicating that the graphite edge and the areas around the edge are the most susceptible to Li plating. However, certain areas of the cells form dead Li whereas others form active Li. We discuss the spatial heterogeneities in four regions: (1) near Cu current collector (CC), (2) in the middle of graphite electrode, (3) at the graphite-separator interface, and (4) in the separator. Specifically, Li near the Cu CC remains active, whereas Li near the interface and in the separator becomes dead at both 1C and 6C. Additionally, a distinct 3D Li morphology is revealed at 6C vs. 1C. Particularly, tip-like Li deposits are observed mostly at 6C that become dead following battery discharging, suggesting a correlation between higher XFC-charging rate/cycling number and the increased formation of tip-like dead Li deposits.

Citation

Joule

Pub Type

Journals

Keywords

plated lithium, in-situ, neutron, tomography, extreme fast charging, lithium-ion battery

Citation

Yusuf, M. , Kaestner, A. , Wied, M. , LaManna, J. , Vo, N. , Dunlop, A. , Jansen, A. , Polzin, B. , Trask, S. , Strobl, M. , Wood, V. , Toney, M. and Weker, J. (2024), Visualizing 3D Morphologies and Spatial Heterogeneities of Li after Fast- Charging via In-situ Neutron Tomography, Joule (Accessed October 2, 2025)