skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Probing the Formation of Cathode-Electrolyte Interphase on Lithium Iron Phosphate Cathodes via Operando Mechanical Measurements

Journal Article · · ACS Applied Materials & Interfaces

Interfacial instabilities in electrodes control the performance and lifetime of Li-ion batteries. While the formation of the solid-electrolyte interphase (SEI) on anodes has received much attention, there is still a lack of understanding the formation of the cathode-electrolyte interphase (CEI) on the cathodes. To fill this gap, we report on dynamic deformations on LiFePO4 cathodes during charge/discharge by utilizing operando digital image correlation, impedance spectroscopy, and cryo X-ray photoelectron spectroscopy. LiFePO4 cathodes were cycled in either LiPF6, LiClO4, or LiTFSI-containing organic liquid electrolytes. Beyond the first cycle, Li-ion intercalation results in a nearly linear correlation between electrochemical strains and the state of (dis)-charge, regardless of the electrolyte chemistry. However, during the first charge in the LiPF6-containing electrolyte, there is a distinct irreversible positive strain evolution at the onset of anodic current rise as well as current decay at around 4.0 V. Impedance studies show an increase in surface resistance in the same potential window, suggesting the formation of CEI layers on the cathode. The chemistry of the CEI layer was characterized by X-ray photoelectron spectroscopy. LiF is detected in the CEI layer starting as early as 3.4 V and LixPOyFz appeared at voltages higher than 4.0 V during the first charge. Our approach offers insights into the formation mechanism of CEI layers on the cathode electrodes, which is crucial for the development of robust cathodes and electrolyte chemistries for higher-performance batteries.

Research Organization:
National Renewable Energy Laboratory (NREL), Golden, CO (United States)
Sponsoring Organization:
USDOE Office of Science (SC), Basic Energy Sciences (BES)
DOE Contract Number:
AC36-08GO28308
OSTI ID:
2203228
Report Number(s):
NREL/JA-5700-87815; MainId:88590; UUID:d39d5203-149e-40fc-80b3-3966ffa99a32; MainAdminID:70903
Journal Information:
ACS Applied Materials & Interfaces, Vol. 15, Issue 36
Country of Publication:
United States
Language:
English

References (43)

Prospects for lithium-ion batteries and beyond—a 2030 vision journal December 2020
Electrochemical energy storage in a sustainable modern society journal January 2014
Intragranular cracking as a critical barrier for high-voltage usage of layer-structured cathode for lithium-ion batteries journal January 2017
Chemomechanical modeling of lithiation-induced failure in high-volume-change electrode materials for lithium ion batteries journal February 2017
Nonaqueous Liquid Electrolytes for Lithium-Based Rechargeable Batteries journal October 2004
Stabilizing cathodes and interphases for next-generation Li-ion batteries journal March 2023
Understanding the Cathode–Electrolyte Interphase in Lithium‐Ion Batteries journal July 2022
Transition Metal Dissolution Mechanisms and Impacts on Electronic Conductivity in Composite LiNi0.5Mn1.5O4 Cathode Films journal November 2022
Direct Detection of Manganese Ions in Organic Electrolyte by UV-vis Spectroscopy journal January 2018
In Situ Development of Elastic Solid Electrolyte Interphase via Nanoregulation and Self-Polymerization of Sodium Itaconate on Graphite Surface journal February 2019
Stable cycling of double-walled silicon nanotube battery anodes through solid–electrolyte interphase control journal March 2012
Photoelectron Spectroscopy for Lithium Battery Interface Studies journal November 2015
Characterization of a model solid electrolyte interphase/carbon interface by combined in situ Raman/Fourier transform infrared microscopy journal September 2013
Cathode-Electrolyte Interphase in Lithium Batteries Revealed by Cryogenic Electron Microscopy journal January 2021
Cryo-EM Reveals the Structure and Chemistry of the Silicon Solid-Electrolyte Interphase journal February 2020
Advanced in situ methods for the characterization of practical electrodes in lithium-ion batteries journal September 2000
The use of in situ techniques in R&D of Li and Mg rechargeable batteries journal February 2011
Solid–Electrolyte Interphase at Positive Electrodes in High‐Energy Li‐Ion Batteries: Current Understanding and Analytical Tools journal April 2020
ALD Protection of Li-Metal Anode Surfaces - Quantifying and Preventing Chemical and Electrochemical Corrosion in Organic Solvent journal August 2016
An electrochemical impedance spectroscopic study of the transport properties of LiNi0.75Co0.25O2 journal December 1999
The Study of Surface Phenomena Related to Electrochemical Lithium Intercalation into Li[sub x]MO[sub y] Host Materials (M = Ni, Mn) journal January 2000
Wet Nanoindentation of the Solid Electrolyte Interphase on Thin Film Si Electrodes journal October 2015
Transition metal dissolution and deposition in Li-ion batteries investigated by operando X-ray absorption spectroscopy journal January 2016
Evaluating the solid electrolyte interphase formed on silicon electrodes: a comparison of ex situ X-ray photoelectron spectroscopy and in situ neutron reflectometry journal January 2016
In Situ Observation of Solid Electrolyte Interphase Formation in Ordered Mesoporous Hard Carbon by Small-Angle Neutron Scattering journal March 2012
Reversible and Irreversible Deformation Mechanisms of Composite Graphite Electrodes in Lithium-Ion Batteries journal January 2016
Strain Evolution in Lithium Manganese Oxide Electrodes journal February 2018
Two-phase transition of Li-intercalation compounds in Li-ion batteries journal November 2014
Approaching Theoretical Capacity of LiFePO[sub 4] at Room Temperature at High Rates journal January 2001
Revisiting LiClO[sub 4] as an Electrolyte for Rechargeable Lithium-Ion Batteries journal January 2010
Effects of cathode electrolyte interfacial (CEI) layer on long term cycling of all-solid-state thin-film batteries journal August 2016
Investigation of the Solid Electrolyte Interphase Formation at Graphite Anodes in Lithium-Ion Batteries with Electrochemical Impedance Spectroscopy journal February 2017
The effect of electrolyte temperature on the passivity of solid electrolyte interphase formed on a graphite electrode journal January 2002
Different Positive Electrodes for Anode-Free Lithium Metal Cells journal April 2022
Electrochemical impedance spectroscopy investigation on battery materials using a symmetrical cell journal May 2021
Failure Study of Commercial LiFePO 4 Cells in Overcharge Conditions Using Electrochemical Impedance Spectroscopy journal January 2015
Influence of electrolyte additives on the cathode electrolyte interphase (CEI) formation on LiNi1/3Mn1/3Co1/3O2 in half cells with Li metal counter electrode journal October 2016
A High Precision Coulometry Study of the SEI Growth in Li/Graphite Cells journal January 2011
High-Precision Coulometry Studies of the Impact of Temperature and Time on SEI Formation in Li-Ion Cells journal January 2018
Elucidating cycling rate-dependent electrochemical strains in sodium iron phosphate cathodes for Na-ion batteries journal September 2021
The study of the anodic stability of alkyl carbonate solutions by in situ FTIR spectroscopy, EQCM, NMR and MS journal February 2001
Gas evolution from cathode materials: A pathway to solvent decomposition concomitant to SEI formation journal October 2013
Rate-dependent electrochemical strain generation in composite iron phosphate cathodes in Li-ion batteries journal August 2022