Operando Quantified Lithium Plating Determination Enabled by Dynamic Capacitance Measurement in Working Li‐Ion Batteries

Abstract

The access to full performance of state‐of‐the‐art Li‐ion batteries (LIBs) is hindered by the mysterious lithium plating behavior. A rapid quantified lithium plating determination method compatible with actual working conditions is an urgent necessity for safe working LIBs. In this contribution, the relationship between electrical double layer (EDL) capacitance and electrochemical active surface area (ECSA) of graphite anodes during the Li‐ion intercalation and Li plating processes is unveiled. We propose an operando lithium plating determination method based on the dynamic capacitance measurement (DCM) test. Reasonable selection of alternating current (AC) frequency protects the anodic responses from the interference of cathodic responses, which allows DCM to be applied in practical LIBs. The onset of lithium plating can be quantitatively traced, demonstrating the promise for real‐time operando determination for lithium plating in a working battery.

Application of Electrochemical Impedance Spectroscopy to Degradation and Aging Research of Lithium-Ion Batteries

“…(e) Schematic illustration of dynamic capacitance measurement method for the operando determination of onset Li plating. Reprinted with permission from ref . Copyright 2022 Elsevier.…”

“…The plating detection method is cross-validated by ex situ mass titrations of Li metal, which proves to possess high Li detection sensitivity (<0.6% of the graphite capacity). Xu et al developed an operando Li plating detection and quantification method based on singlefrequency DEIS: 151 Since Li plating causes a big enhancement of electrochemical active surface area (ECSA) so as to increase the electrochemical double layer capacitance (EDLC), the EDLC on the surface of graphite anode could be used as a quantitative indicator for Li plating. The characteristic frequency of the charge-transfer process of the graphite anode is first determined as 15 Hz and used in singlefrequency DEIS to observe the dynamic capacitance variation during charging.…”

Quantifying the Influence of Li Plating on a Graphite Anode by Mass Spectrometry

“…to detect deposited Li on an anode, but these post mortem/ex situ characterizations require cells to be torn down prior to measurement and cannot have an effective role for very early safety warnings. , Therefore, a nondestructive operando/in situ technology is urgently needed to detect the onset of local Li plating (e.g., corresponding time, voltage, or capacity, etc. ). , More importantly, a precise/effective quantitative method is further needed to help quantify the irreversible capacity loss on the Gr anode and corresponding influence of the Gr electrolyte interface (e.g., components and construction), pointing out explicit/clear direction for an electrolyte modification strategy to restrain the unwanted Li plating. − …”

“…18,19 Therefore, a nondestructive operando/in situ technology is urgently needed to detect the onset of local Li plating (e.g., corresponding time, voltage, or capacity, etc.). 20,21 More importantly, a precise/effective quantitative method is further needed to help quantify the irreversible capacity loss on the Gr anode and corresponding influence of the Gr electrolyte interface (e.g., components and construction), pointing out explicit/clear direction for an electrolyte modification strategy to restrain the unwanted Li plating. 22−25 In this study, we employed an online electrochemical mass spectrometry (OEMS) method 26−28 to clearly and accurately detect the onset of microscale Li plating in real time based on H 2 evolution capture from the reaction of plated Li with the polymer binder.…”

Titration Mass Spectroscopy (TMS): A Quantitative Analytical Technology for Rechargeable Batteries

“…The deposition of dead Li 0 has been regarded as a threat against the practical application of a typical graphite anode, especially on fast-charging and low-temperature operation environments in a full-cell system. − Herein, compared with typical graphite-intercalation chemistry (GIC) with 100% SoD% (blue trace, Figure d), we simulate dead Li 0 deposition on graphite by 120% SoD over-discharging in a graphite-Li half-cell (red trace, Figure d). After quantification of delithiated/charged states by D 2 O-based TMS (Figure e,f), the graphite anode cycled with 100% SoD does not present obvious dead Li 0 , while the 120% SoD GIC process leads to an additional 10.77 mAh/g of dead-Li 0 -induced irreversible capacity loss.…”