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Abstract A low‐carbon future demands more affordable batteries utilizing abundant elements with sustainable end‐of‐life battery management. Despite the economic and environmental advantages of Li‐MnO2batteries, their application so far has been largely constrained to primary batteries. Here, we demonstrate that one of the major limiting factors preventing the stable cycling of Li‐MnO2batteries, Mn dissolution, can be effectively mitigated by employing a common ether electrolyte, 1 mol/L lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) in 1,3‐dioxane (DOL)/1,2‐dimethoxyethane (DME). We discover that the suppression of this dissolution enables highly reversible cycling of the MnO2cathode regardless of the synthesized phase and morphology. Moreover, we find that both the LiPF6salt and carbonate solvents present in conventional electrolytes are responsible for previous cycling challenges. The ether electrolyte, paired with MnO2cathodes is able to demonstrate stable cycling performance at various rates, even at elevated temperature such as 60°C. Our discovery not only represents a defining step in Li‐MnO2batteries with extended life but provides design criteria of electrolytes for vast manganese‐based cathodes in rechargeable batteries.
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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.
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- PAR ID:
- 10537400
- 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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- Free Publicly Accessible Full Text
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Accepted Manuscript
- Journal Article:
- https://doi.org/10.1002/adma.202302595
