Electrolyte additives to enable nonaqueous polyelectrolyte solutions for lithium ion batteries

Date Published
07/2019
Publication Type
Journal Article
Authors
DOI
10.1039/c9me00067d
Abstract

Nonaqueous polyelectrolyte solutions, in which a negatively charged macromolecule neutralized by lithium is dissolved in nonaqueous solvents, have shown promise as potential high transference number electrolytes. However, in battery-relevant carbonate solvents (ethylene carbonate/dimethyl carbonate blends), it has been shown that lithium ions do not readily dissociate from easily synthesized sulfonated polymers, despite the solvent's high dielectric constant (∼50). In this work, a range of additives are screened to improve conductivity, and we demonstrate that the addition of less than 5 vol% of 15-crown-5 achieves an order of magnitude conductivity increase by selectively improving lithium dissociation. Utilizing the optimized electrolyte, we show that polyelectrolyte solutions may be directly substituted for a standard electrolyte with commercial electrodes in a graphite/LiFePO4 cell, providing further motivation for future study of these new electrolytes.

Journal
Molecular Systems Design & Engineering
Volume
5
Year of Publication
2020
Issue
1
Pagination
91 - 96
Short Title
Mol. Syst. Des. Eng.
Refereed Designation
Refereed
Organizations
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