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Over the past years, lithium-ion solid-state batteries have demonstrated significant advancements regarding such properties as safety, long-term endurance, and energy density. Solid-state electrolytes based on lithium halides offer new opportunities due to their unique features such as a broad electrochemical stability window, high lithium-ion conductivity, and elasticity at close to melting point temperatures that could enhance lithium-ion transport at interfaces. A comparative study of lithium indium halide (Li3InCl6) electrolytes synthesized through a mechano-thermal method with varying optimization parameters revealed a significant effect of temperature and pressure on lithium-ion transport. An analysis of Electrochemical Impedance Spectroscopy (EIS) data within the temperature range of 25–100 °C revealed that the optimized Li3InCl6 electrolyte reveals high ionic conductivity, reaching 1.0 mS cm−1 at room temperature. Herein, we present the utilization of in situ/operando X-ray Photoelectron Spectroscopy (XPS) and in situ X-ray powder diffraction (XRD) to investigate the temperature-dependent behavior of the Li3InCl6 electrolyte. Confirmed by these methods, significant changes in the Li3InCl6 ionic conductivity at 70 °C were observed due to phase transformation. The observed behavior provides critical information for practical applications of the Li3InCl6 solid-state electrolyte in a broad temperature range, contributing to the enhancement of lithium-ion solid-state batteries through their improved morphology, chemical interactions, and structural integrity.
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Impact of Structural Deformations on the Performance of Li-Ion Insertion Hosts
Over the course of more than three decades, Li-ion batteries have come to revolutionize the way we store and transport energy. These incredibly compact electrochemical devices rely fundamentally on the ability to reversibly insert lithium ions into densely packed arrangements of atoms. Of the tens of thousands of materials reported in the structural databases, only a very small number have been shown to be capable of accommodating the kind of fast ionic diffusion necessary to operate in practical devices. In honor of John B. Goodenough’s 100th birthday, this perspective will overview the current understanding of the kinds of structural features that help and/or hurt fast lithium ion transport through insertion hosts, with a particular focus on the role that the rotation of rigid subunits plays in the movement of lithium through the solid state.
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- Award ID(s):
- 1554204
- PAR ID:
- 10326735
- Date Published:
- Journal Name:
- Chemistry of Materials
- ISSN:
- 0897-4756
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1021/acs.chemmater.2c00331
