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Potentiometric MRI of a Superconcentrated Lithium Electrolyte: Testing the Irreversible Thermodynamics Approach

[Image: see text] Superconcentrated electrolytes, being highly thermodynamically nonideal, provide a stringent proving ground for continuum transport theories. Herein, we test an ostensibly complete model of LiPF(6) in ethyl-methyl carbonate (EMC) based on the Onsager–Stefan–Maxwell theory from irre...

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Autores principales: Wang, Andrew A., Gunnarsdóttir, Anna B., Fawdon, Jack, Pasta, Mauro, Grey, Clare P., Monroe, Charles W.
Formato: Online Artículo Texto
Lenguaje:English
Publicado: American Chemical Society 2021
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8438662/
https://www.ncbi.nlm.nih.gov/pubmed/34541321
http://dx.doi.org/10.1021/acsenergylett.1c01213
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author Wang, Andrew A.
Gunnarsdóttir, Anna B.
Fawdon, Jack
Pasta, Mauro
Grey, Clare P.
Monroe, Charles W.
author_facet Wang, Andrew A.
Gunnarsdóttir, Anna B.
Fawdon, Jack
Pasta, Mauro
Grey, Clare P.
Monroe, Charles W.
author_sort Wang, Andrew A.
collection PubMed
description [Image: see text] Superconcentrated electrolytes, being highly thermodynamically nonideal, provide a stringent proving ground for continuum transport theories. Herein, we test an ostensibly complete model of LiPF(6) in ethyl-methyl carbonate (EMC) based on the Onsager–Stefan–Maxwell theory from irreversible thermodynamics. We perform synchronous magnetic resonance imaging (MRI) and chronopotentiometry to examine how superconcentrated LiPF(6):EMC responds to galvanostatic polarization and open-circuit relaxation. We simulate this experiment using an independently parametrized model with six composition-dependent electrolyte properties, quantified up to saturation. Spectroscopy reveals increasing ion association and solvent coordination with salt concentration. The potentiometric MRI data agree closely with the predicted ion distributions and overpotentials, providing a completely independent validation of the theory. Superconcentrated electrolytes exhibit strong cation–anion interactions and extreme solute-volume effects that mimic elevated lithium transference. Our simulations allow surface overpotentials to be extracted from cell-voltage data to track lithium interfaces. Potentiometric MRI is a powerful tool to illuminate electrolytic transport phenomena.
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spelling pubmed-84386622021-09-15 Potentiometric MRI of a Superconcentrated Lithium Electrolyte: Testing the Irreversible Thermodynamics Approach Wang, Andrew A. Gunnarsdóttir, Anna B. Fawdon, Jack Pasta, Mauro Grey, Clare P. Monroe, Charles W. ACS Energy Lett [Image: see text] Superconcentrated electrolytes, being highly thermodynamically nonideal, provide a stringent proving ground for continuum transport theories. Herein, we test an ostensibly complete model of LiPF(6) in ethyl-methyl carbonate (EMC) based on the Onsager–Stefan–Maxwell theory from irreversible thermodynamics. We perform synchronous magnetic resonance imaging (MRI) and chronopotentiometry to examine how superconcentrated LiPF(6):EMC responds to galvanostatic polarization and open-circuit relaxation. We simulate this experiment using an independently parametrized model with six composition-dependent electrolyte properties, quantified up to saturation. Spectroscopy reveals increasing ion association and solvent coordination with salt concentration. The potentiometric MRI data agree closely with the predicted ion distributions and overpotentials, providing a completely independent validation of the theory. Superconcentrated electrolytes exhibit strong cation–anion interactions and extreme solute-volume effects that mimic elevated lithium transference. Our simulations allow surface overpotentials to be extracted from cell-voltage data to track lithium interfaces. Potentiometric MRI is a powerful tool to illuminate electrolytic transport phenomena. American Chemical Society 2021-08-15 2021-09-10 /pmc/articles/PMC8438662/ /pubmed/34541321 http://dx.doi.org/10.1021/acsenergylett.1c01213 Text en © 2021 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 Wang, Andrew A.
Gunnarsdóttir, Anna B.
Fawdon, Jack
Pasta, Mauro
Grey, Clare P.
Monroe, Charles W.
Potentiometric MRI of a Superconcentrated Lithium Electrolyte: Testing the Irreversible Thermodynamics Approach
title Potentiometric MRI of a Superconcentrated Lithium Electrolyte: Testing the Irreversible Thermodynamics Approach
title_full Potentiometric MRI of a Superconcentrated Lithium Electrolyte: Testing the Irreversible Thermodynamics Approach
title_fullStr Potentiometric MRI of a Superconcentrated Lithium Electrolyte: Testing the Irreversible Thermodynamics Approach
title_full_unstemmed Potentiometric MRI of a Superconcentrated Lithium Electrolyte: Testing the Irreversible Thermodynamics Approach
title_short Potentiometric MRI of a Superconcentrated Lithium Electrolyte: Testing the Irreversible Thermodynamics Approach
title_sort potentiometric mri of a superconcentrated lithium electrolyte: testing the irreversible thermodynamics approach
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8438662/
https://www.ncbi.nlm.nih.gov/pubmed/34541321
http://dx.doi.org/10.1021/acsenergylett.1c01213
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