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Abstract Solid‐state lithium metal batteries with garnet‐type electrolyte provide several advantages over conventional lithium‐ion batteries, especially for safety and energy density. However, a few grand challenges such as the propagation of Li dendrites, poor interfacial contact between the solid electrolyte and the electrodes, and formation of lithium carbonate during ambient exposure over the solid‐state electrolyte prevent the viability of such batteries. Herein, an ultrathin sub‐nanometer porous carbon nanomembrane (CNM) is employed on the surface of solid‐state electrolyte (SSE) that increases the adhesion of SSE with electrodes, prevents lithium carbonate formation over the surface, regulates the flow of Li‐ions, and blocks any electronic leakage. The sub‐nanometer scale pores in CNM allow rapid permeation of Li‐ions across the electrode–electrolyte interface without the presence of any liquid medium. Additionally, CNM suppresses the propagation of Li dendrites by over sevenfold up to a current density of 0.7 mA cm−2and enables the cycling of all‐solid‐state batteries at low stack pressure of 2 MPa using LiFePO4cathode and Li metal anode. The CNM provides chemical stability to the solid electrolyte for over 4 weeks of ambient exposure with less than a 4% increase in surface impurities.
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Probing lithium mobility at a solid electrolyte surface
Abstract Solid-state electrolytes overcome many challenges of present-day lithium ion batteries, such as safety hazards and dendrite formation1,2. However, detailed understanding of the involved lithium dynamics is missing due to a lack of in operando measurements with chemical and interfacial specificity. Here we investigate a prototypical solid-state electrolyte using linear and nonlinear extreme-ultraviolet spectroscopies. Leveraging the surface sensitivity of extreme-ultraviolet-second-harmonic-generation spectroscopy, we obtained a direct spectral signature of surface lithium ions, showing a distinct blueshift relative to bulk absorption spectra. First-principles simulations attributed the shift to transitions from the lithium 1 sstate to hybridized Li-s/Ti-dorbitals at the surface. Our calculations further suggest a reduction in lithium interfacial mobility due to suppressed low-frequency rattling modes, which is the fundamental origin of the large interfacial resistance in this material. Our findings pave the way for new optimization strategies to develop these electrochemical devices via interfacial engineering of lithium ions.
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- PAR ID:
- 10481664
- Author(s) / Creator(s):
- ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more »
- Publisher / Repository:
- Nature Materials
- Date Published:
- Journal Name:
- Nature Materials
- Volume:
- 22
- Issue:
- 7
- ISSN:
- 1476-1122
- Page Range / eLocation ID:
- 848 to 852
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript
- Journal Article:
- https://doi.org/10.1038/s41563-023-01535-y
