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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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Prelithiation of Alloy Anodes via Roll Pressing for Solid‐State Batteries
Abstract Solid‐state batteries with alloy‐type negative electrodes can feature enhanced energy density and safety compared to conventional Li‐ion batteries. However, diffusional Li trapping within Li alloys often causes low initial Coulombic efficiency and leads to capacity loss with cycling. Here, a general roll‐pressing prelithiation method compatible with a variety of alloy‐type negative electrodes (silicon, aluminum, tin, and multi‐phase alloys) is introduced, which is shown to improve performance in solid‐state batteries. By warm‐rolling lithium foil of controlled thickness with various alloy‐type electrodes, both slurry‐cast and foil‐type electrodes can be uniformly prelithiated via direct chemical reaction. The prelithiated electrodes exhibit enhanced specific capacity and extended cycle life in batteries with Li6PS5Cl solid‐state electrolyte. Prelithiated multi‐phase foil electrodes with a tailored interface are shown to exhibit superior cycling stability down to 2 MPa stack pressure. This prelithiation technique offers a pathway to overcome intrinsic challenges in alloy anodes for solid‐state batteries.
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- Award ID(s):
- 2209202
- PAR ID:
- 10640117
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Materials
- ISSN:
- 0935-9648
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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