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Abstract LiNO3is a widely used salt‐additive that markedly improves the stability of ether‐based electrolytes at a Li metal anode but is generally regarded as incompatible with alkyl carbonates. Here we find that contrary to common wisdom, cyclic carbonate solvents such as ethylene carbonate can dissolve up to 0.7 M LiNO3without any additives, largely improving the anode reversibility. We demonstrate the significance of our findings by upgrading various state‐of‐the‐art carbonate electrolytes with LiNO3, which provides large improvements in batteries composed of thin lithium (50 μm) anode and high voltage cathodes. Capacity retentions of 90.5 % after 600 cycles and 92.5 % after 200 cycles are reported for LiNi0.6Mn0.2Co0.2O2(2 mAh cm−2, 0.5 C) and LiNi0.8Mn0.1Co0.1O2cathode (4 mAh cm−2, 0.2 C), respectively. 1 Ah pouch cells (≈300 Wh kg−1) retain more than 87.9 % after 100 cycles at 0.5 C. This work illustrates that reforming traditional carbonate electrolytes provides a scalable, cost‐effective approach towards practical LMBs.
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This content will become publicly available on April 30, 2026
Designing Lithiophilic Lithium Metal Surface by a Hybrid Covalent Organic Framework and MXene Coating
Abstract With the increasing demand for developing large‐energy‐density and safe batteries, a reliable lithium metal as an anode becomes more and more important in various lithium metal and solid‐state batteries. On the basis of better lithium regulation from MXene, a lithiophilic lithium metal surface is designed by introducing a 2D hybrid coating that consists of a thin covalent organic framework (COF‐1) modified MXene layer (denoted as COF‐MXene‐Li). The abundant lithiophilic boroxine sites on 2D COF‐1 attract lithium ions while the MXene further regulates lithium homogeneous nucleation and growth, thus preventing dendrite formation. The coin cell battery paired with LiNi0.8Mn0.1Co0.1O2(NMC811) as cathode material displays 17% more capacity retention compared with pure lithium metal after 400 cycles at 0.5C.Over 81.4% capacity retention along with 99.96% Coulombic efficiency (CE) of a 1.0 Ah pouch cell versus LiNi0.8Co0.15Al0.05O2(NCA) after 250 cycles is received. The assembled 1.6 Ah pouch cell with NMC811 show an energy density of up to 366.7 Wh Kg−1and an actual energy density based on the whole cell of up to 339.7 Wh Kg−1. The improved cycling stability particularly in pouch cells opens broad applications for this hybrid coating modified lithium metal as anode electrode in a variety of large‐energy‐density battery systems.
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- Award ID(s):
- 2013525
- PAR ID:
- 10586563
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Small
- Volume:
- 21
- Issue:
- 23
- ISSN:
- 1613-6810
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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