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Abstract A thin solid electrolyte with a high Li+conductivity is used to separate the metallic lithium anode and the cathode in an all‐solid‐state Li‐metal battery. However, most solid Li‐ion electrolytes have a small electrochemical stability window, large interfacial resistance, and cannot block lithium‐dendrite growth when lithium is plated on charging of the cell. Mg2+stabilizes a rhombohedral NASICON‐structured solid electrolyte of the formula Li1.2Mg0.1Zr1.9(PO4)3(LMZP). This solid electrolyte has Li‐ion conductivity two orders of magnitude higher at 25 °C than that of the triclinic LiZr2(PO4)3.7Li and6Li NMR confirm the Li‐ions in two different crystallographic sites of the NASICON framework with 85% of the Li‐ions having a relatively higher mobility than the other 15%. The anode–electrolyte interface is further investigated with symmetric Li/LMZP/Li cell testing, while the cathode–electrolyte interface is explored with an all‐solid‐state Li/LMZP/LiFePO4cell. The enhanced performance of these cells enabled by the Li1.2Mg0.1Zr1.9(PO4)3solid electrolyte is stable upon repeated charge/discharge cycling.
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This content will become publicly available on July 27, 2026
Calix[4]pyrrole‐Based Wavy Covalent Organic Framework: A Protective Layer for High Performance Lithium‐Metal Batteries
Abstract Practical applications of lithium metal batteries are often limited by low cycling efficiencies and uncontrolled lithium dendrite growth caused by unstable and heterogeneous lithium‐electrolyte interfaces. To address this issue, a calix[4]pyrrole‐based wavy covalent organic framework (WCOF) is developed that acts as a protective layer to suppress Li dendrite growth and reduce side reactions on the Li anode. The presentWCOFis porous and contains calix[4]pyrrole units acting as “molecular traps” that allow efficient PF6−anion capture while allowing for uniform Li+diffusion. This provides structurally stable artificial protective layers that permit high Li+transference numbers. The resulting solid electrolyte interphases permit ultralong‐term stable cycling at a current density of 1 mA cm−2and reversible lithium plating/stripping (over 2500 h) at an areal capacity of 2 mAh cm−2. The protected anodes of this study also demonstrated excellent cell stability through 260 cycles when paired with high‐voltage cathodes (NCM811 with high mass loading: 20 mg cm−2).
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- Award ID(s):
- 2304731
- PAR ID:
- 10646257
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Small
- Volume:
- 21
- Issue:
- 37
- ISSN:
- 1613-6810
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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