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Title: Stabilizing electrode–electrolyte interfaces to realize high-voltage Li||LiCoO 2 batteries by a sulfonamide-based electrolyte
High-voltage lithium-metal batteries (LMBs) with LiCoO 2 (LCO) as the cathode have high volumetric and gravimetric energy densities. However, it remains a challenge for stable cycling of LCO >4.5 V Li . Here we demonstrate that a rationally designed sulfonamide-based electrolyte can greatly improve the cycling stability at high voltages up to 4.7 V Li by stabilizing the electrode–electrolyte interfaces (EEIs) on both the Li-metal anode (LMA) and high-voltage LCO cathode. With the sulfonamide-based electrolyte, commercial LCO cathodes retain 89% and 85% of their capacities after 200 and 100 cycles under high charging voltages of 4.55 V Li and 4.6 V Li , respectively, significantly outperforming traditional carbonate-based electrolytes. The surface degradation, impedance growth, and detrimental side reactions in terms of gas evolution and Co dissolution are well suppressed. Our work demonstrates a promising strategy for designing new electrolytes to realize high-energy Li||LCO batteries.  more » « less
Award ID(s):
2034899 2034902
PAR ID:
10366160
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ;
Date Published:
Journal Name:
Energy & Environmental Science
Volume:
14
Issue:
11
ISSN:
1754-5692
Page Range / eLocation ID:
6030 to 6040
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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