Cargando…

Mass and Charge Transport in Li(1−δ)CoO(2) Thin Films—A Complete Set of Properties and Its Defect Chemical Interpretation

[Image: see text] Lithium insertion materials are an essential class of mixed ionic and electronic conductors, and their electrochemical properties depend on the resistive and capacitive interplay of ions and electrons. However, complete sets of the corresponding elementary material parameters, that...

Descripción completa

Detalles Bibliográficos
Autores principales: Bumberger, Andreas E., Steinbach, Claudia, Ring, Joseph, Fleig, Juergen
Formato: Online Artículo Texto
Lenguaje:English
Publicado: American Chemical Society 2022
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9753594/
https://www.ncbi.nlm.nih.gov/pubmed/36530944
http://dx.doi.org/10.1021/acs.chemmater.2c02614
_version_ 1784850998137716736
author Bumberger, Andreas E.
Steinbach, Claudia
Ring, Joseph
Fleig, Juergen
author_facet Bumberger, Andreas E.
Steinbach, Claudia
Ring, Joseph
Fleig, Juergen
author_sort Bumberger, Andreas E.
collection PubMed
description [Image: see text] Lithium insertion materials are an essential class of mixed ionic and electronic conductors, and their electrochemical properties depend on the resistive and capacitive interplay of ions and electrons. However, complete sets of the corresponding elementary material parameters, that is, composition-dependent ionic and electronic conductivity, chemical capacitance, and charge-transfer resistance, are rarely reported for lithium-ion battery electrode materials. Moreover, the interpretation of these properties from a defect chemical point of view is not very common. In this work, the impedance of sputtered Li(1−δ)CoO(2) thin films is analyzed to extract the fundamental electrochemical properties as a function of state-of-charge (SOC). Within the accessible SOC range, the charge transfer resistance and ionic conductivity vary by more than 1 order of magnitude. The chemical capacitance determined from impedance spectra agrees excellently with the differential capacitance from charge/discharge curves, and, in the dilute regime, even matches the absolute values predicted by defect thermodynamics. The evolution of lithium diffusivity along the charge curve is deconvoluted into the separate contributions of ionic conductivity and chemical capacitance. Finally, we apply the principles of defect chemistry to evaluate the observed trends in terms of lithium activity and point defect concentrations and provide a tentative defect model that is consistent with our results. The consistency of impedance measurements, cycling data, and thermodynamic theory highlights the key role of the chemical capacitance as a powerful material descriptor and emphasizes the relevance of defect chemical concepts for all lithium insertion electrode materials.
format Online
Article
Text
id pubmed-9753594
institution National Center for Biotechnology Information
language English
publishDate 2022
publisher American Chemical Society
record_format MEDLINE/PubMed
spelling pubmed-97535942022-12-16 Mass and Charge Transport in Li(1−δ)CoO(2) Thin Films—A Complete Set of Properties and Its Defect Chemical Interpretation Bumberger, Andreas E. Steinbach, Claudia Ring, Joseph Fleig, Juergen Chem Mater [Image: see text] Lithium insertion materials are an essential class of mixed ionic and electronic conductors, and their electrochemical properties depend on the resistive and capacitive interplay of ions and electrons. However, complete sets of the corresponding elementary material parameters, that is, composition-dependent ionic and electronic conductivity, chemical capacitance, and charge-transfer resistance, are rarely reported for lithium-ion battery electrode materials. Moreover, the interpretation of these properties from a defect chemical point of view is not very common. In this work, the impedance of sputtered Li(1−δ)CoO(2) thin films is analyzed to extract the fundamental electrochemical properties as a function of state-of-charge (SOC). Within the accessible SOC range, the charge transfer resistance and ionic conductivity vary by more than 1 order of magnitude. The chemical capacitance determined from impedance spectra agrees excellently with the differential capacitance from charge/discharge curves, and, in the dilute regime, even matches the absolute values predicted by defect thermodynamics. The evolution of lithium diffusivity along the charge curve is deconvoluted into the separate contributions of ionic conductivity and chemical capacitance. Finally, we apply the principles of defect chemistry to evaluate the observed trends in terms of lithium activity and point defect concentrations and provide a tentative defect model that is consistent with our results. The consistency of impedance measurements, cycling data, and thermodynamic theory highlights the key role of the chemical capacitance as a powerful material descriptor and emphasizes the relevance of defect chemical concepts for all lithium insertion electrode materials. American Chemical Society 2022-11-21 2022-12-13 /pmc/articles/PMC9753594/ /pubmed/36530944 http://dx.doi.org/10.1021/acs.chemmater.2c02614 Text en © 2022 The Authors. Published by American Chemical Society https://creativecommons.org/licenses/by/4.0/Permits the broadest form of re-use including for commercial purposes, provided that author attribution and integrity are maintained (https://creativecommons.org/licenses/by/4.0/).
spellingShingle Bumberger, Andreas E.
Steinbach, Claudia
Ring, Joseph
Fleig, Juergen
Mass and Charge Transport in Li(1−δ)CoO(2) Thin Films—A Complete Set of Properties and Its Defect Chemical Interpretation
title Mass and Charge Transport in Li(1−δ)CoO(2) Thin Films—A Complete Set of Properties and Its Defect Chemical Interpretation
title_full Mass and Charge Transport in Li(1−δ)CoO(2) Thin Films—A Complete Set of Properties and Its Defect Chemical Interpretation
title_fullStr Mass and Charge Transport in Li(1−δ)CoO(2) Thin Films—A Complete Set of Properties and Its Defect Chemical Interpretation
title_full_unstemmed Mass and Charge Transport in Li(1−δ)CoO(2) Thin Films—A Complete Set of Properties and Its Defect Chemical Interpretation
title_short Mass and Charge Transport in Li(1−δ)CoO(2) Thin Films—A Complete Set of Properties and Its Defect Chemical Interpretation
title_sort mass and charge transport in li(1−δ)coo(2) thin films—a complete set of properties and its defect chemical interpretation
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9753594/
https://www.ncbi.nlm.nih.gov/pubmed/36530944
http://dx.doi.org/10.1021/acs.chemmater.2c02614
work_keys_str_mv AT bumbergerandrease massandchargetransportinli1dcoo2thinfilmsacompletesetofpropertiesanditsdefectchemicalinterpretation
AT steinbachclaudia massandchargetransportinli1dcoo2thinfilmsacompletesetofpropertiesanditsdefectchemicalinterpretation
AT ringjoseph massandchargetransportinli1dcoo2thinfilmsacompletesetofpropertiesanditsdefectchemicalinterpretation
AT fleigjuergen massandchargetransportinli1dcoo2thinfilmsacompletesetofpropertiesanditsdefectchemicalinterpretation