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Title: A fast and stable Li metal anode incorporating an Mo 6 S 8 artificial interphase with super Li-ion conductivity
The poor interfacial stability of Li metal leads to formation of unstable solid-electrolyte interphases (SEIs) and severely limits its practical applications. Protecting Li metal with an artificial SEI that has balanced stability, conductivity and mechanical strength is critical. Here we demonstrate a design strategy for stabilizing Li using Mo 6 S 8 /carbon artificial SEI films. These films are directly coated on Li foil and the Mo 6 S 8 particles provide ordered conduction channels for fast but regulated Li-ion flux, and provide hybrid anodes that have nearly four times higher exchange current densities. They also have seamless contact with Li metal and protect it from parasitic reactions, and hence significantly improve its stability. Consequently, Li metal batteries in which the hybrid anodes were paired with LiNi 0.8 Mn 0.1 Co 0.1 O 2 cathodes (3.0 mA h per cell) exhibited significantly improved cycling stability (63% vs. 25% retention) and a stabilized Li interphase compared with pristine Li anodes.  more » « less
Award ID(s):
1659548
PAR ID:
10154730
Author(s) / Creator(s):
; ; ; ;
Date Published:
Journal Name:
Journal of Materials Chemistry A
Volume:
7
Issue:
11
ISSN:
2050-7488
Page Range / eLocation ID:
6038 to 6044
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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