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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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Suppression of High Spin State of Mn for the Improvement of Mn‐Based Materials in Rechargeable Batteries
Abstract Manganese‐based materials are essential for developing safe, cost‐effective, and environmentally sustainable rechargeable batteries, which are critical for advancing clean energy technologies. However, the high spin state of the Mn cation triggers a pronounced Jahn–Teller effect and phase transformations during cycling, leading to structural instability and reduced electrochemical performance of the Mn‐based cathodes. This review provides a fundamental understanding of the Jahn–Teller effect, highlights recent strategies to mitigate the high spin state of Mn, and offers insights into future research directions aimed at overcoming the Jahn–Teller effect to enhance the performance of next‐generation Mn‐based cathodes for rechargeable batteries.
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- Award ID(s):
- 1949840
- PAR ID:
- 10611428
- Publisher / Repository:
- Wiley
- Date Published:
- Journal Name:
- Small
- ISSN:
- 1613-6810
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1002/smll.202410453
