%0 Journal Article %A David E Brown %A Eric J McShane %A Zachary M Konz %A Kristian B Knudsen %A Bryan D McCloskey %B Cell Reports Physical Science %D 2021 %G eng %N 10 %P 100589 %R 10.1016/j.xcrp.2021.100589 %T Detecting onset of lithium plating during fast charging of Li-ion batteries using operando electrochemical impedance spectroscopy %U https://linkinghub.elsevier.com/retrieve/pii/S2666386421003040 %V 2 %8 10/2021 %! Cell Reports Physical Science %X

Electrochemical plating of Li metal on the graphite electrode is the key limitation behind slow charging times of Li-ion batteries (LIBs) in electric vehicles (EVs). Currently, electrochemical methods to detect the onset of Li plating while a battery is fast charging are sparse. In this study, we use operando electrochemical impedance spectroscopy to reliably detect the onset of Li plating on graphite electrodes in three-electrode LIBs. An increase in the graphite solid-electrolyte interface (SEI) resistance indicates that Li plating has occurred. By cross-validating with a highly sensitive ex situ chemical titration, we determine that this technique can detect very small amounts of plated Li (<0.6% of the graphite electrode’s capacity). We also offer physical explanations for the observed impedance behavior. Finally, we show that this technique can be applied to standard two-electrode LIB systems, making the method an important step toward safely implementing fast charging protocols for LIBs in EVs.