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Title: Li 2 MnO 3 : A Catalyst for a Liquid Cl 2 Electrode in Low‐Temperature Aqueous Batteries
Abstract Li2MnO3has been contemplated as a high‐capacity cathode candidate for Li‐ion batteries; however, it evolves oxygen during battery charging under ambient conditions, which hinders a reversible reaction. However, it is unclear if this irreversible process still holds under subambient conditions. Here, the low‐temperature electrochemical properties of Li2MnO3in an aqueous LiCl electrolyte are evaluated and a reversible discharge capacity of 302 mAh g−1at a potential of 1.0 V versus Ag/AgCl at −78 °C with good rate capability and stable cycling performance, in sharp contrast to the findings in a typical Li2MnO3cell cycled at room temperature, is observed. However, the results reveal that the capacity does not originate from the reversible oxygen oxidation in Li2MnO3but the reversible Cl2(l)/Cl−(aq.) redox from the electrolyte. The results demonstrate the good catalytic properties of Li2MnO3to promote the Cl2/Cl−redox at low temperatures.  more » « less
Award ID(s):
2221645 2221646
PAR ID:
10537400
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ;
Publisher / Repository:
Wiley
Date Published:
Journal Name:
Advanced Materials
Volume:
35
Issue:
47
ISSN:
0935-9648
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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