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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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Ultra‐Thin Lithium Silicide Interlayer for Solid‐State Lithium‐Metal Batteries
Abstract All‐solid‐state batteries with metallic lithium (LiBCC) anode and solid electrolyte (SE) are under active development. However, an unstable SE/LiBCCinterface due to electrochemical and mechanical instabilities hinders their operation. Herein, an ultra‐thin nanoporous mixed ionic and electronic conductor (MIEC) interlayer (≈3.25 µm), which regulates LiBCCdeposition and stripping, serving as a 3D scaffold for Li0ad‐atom formation, LiBCCnucleation, and long‐range transport of ions and electrons at SE/LiBCCinterface is demonstrated. Consisting of lithium silicide and carbon nanotubes, the MIEC interlayer is thermodynamically stable against LiBCCand highly lithiophilic. Moreover, its nanopores (<100 nm) confine the deposited LiBCCto the size regime where LiBCCexhibits “smaller is much softer” size‐dependent plasticity governed by diffusive deformation mechanisms. The LiBCCthus remains soft enough not to mechanically penetrate SE in contact. Upon further plating, LiBCCgrows in between the current collector and the MIEC interlayer, not directly contacting the SE. As a result, a full‐cell having Li3.75Si‐CNT/LiBCCfoil as an anode and LiNi0.8Co0.1Mn0.1O2as a cathode displays a high specific capacity of 207.8 mAh g−1, 92.0% initial Coulombic efficiency, 88.9% capacity retention after 200 cycles (Coulombic efficiency reaches 99.9% after tens of cycles), and excellent rate capability (76% at 5 C).
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- Award ID(s):
- 2034902
- PAR ID:
- 10419121
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Materials
- Volume:
- 35
- Issue:
- 22
- ISSN:
- 0935-9648
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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