Using In Situ High-Energy X-ray Diffraction to Quantify Electrode Behavior of Li-Ion Batteries from Extreme Fast Charging

作者：Partha P. Paul, Chuntian Cao, Vivek Thampy, Hans‐Georg Steinrück, Tanvir R. Tanim, Alison R. Dunlop, Stephen E. Trask, Andrew N. Jansen, Eric J. Dufek, Johanna Nelson Weker, Michael F. Toney · 发表于：ACS Applied Energy Materials · 年份：2021 · DOI：10.1021/acsaem.1c02348 · 被引用次数：28 · 研究领域：Advancements in Battery Materials、Advanced Battery Technologies Research、Advanced Battery Materials and Technologies

Extreme fast charging (XFC, ≤15 min charging time) of Li-ion batteries (LIBs) has been proposed as an immediate target to increase the commercial appeal of electric vehicles. However, XFC of LIBs is associated with the degradation of battery performance and safety concerns. Quantitative and simultaneous characterization of various components during cell degradation represents a major experimental challenge. In this work, we outline a methodology for the use of spatially resolved, high-energy X-ray diffraction as a quantitative, in situ method of mapping the degradation of LIBs. We use this approach to study the battery cell capacity loss, both locally (mm scale) and globally over the entire cell (cm scale). Specifically, our workflow allows us to quantify the total amount of plated Li on the anode, as well as its spatial correlation to the structural properties of the anode and cathode. The method complements existing optical methods to resolve the spatial heterogeneity of local degradation mechanisms such as Li plating and provides simultaneous insights into concomitant anode state-of-charge variability. We apply it to commercially relevant single-layer pouch cells with the graphite anode and the LiNi 0.5 Mn 0.3 Co 0.2 O 2 cathode. Our results show that Li plating occurs heterogeneously on the graphite anode and that it is spatially correlated to the extent of anode lithiation. We anticipate that the described workflow will allow for understanding multiscale degradation in e...