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Title: 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).  more » « less
Award ID(s):
2034902
PAR ID:
10474522
Author(s) / Creator(s):
; ; ; ; ; ;
Publisher / Repository:
Wiley
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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