Earth-abundant, cost-effective electrode materials are essential for sustainable rechargeable batteries and global decarbonization. Manganese dioxide (MnO2) and hard carbon both exhibit high structural and chemical tunability, making them excellent electrode candidates for batteries. Herein, we elucidate the impact of electrolytes on the cycling performance of commercial electrolytic manganese dioxide in Li chemistry. We leverage synchrotron X-ray analysis to discern the chemical state and local structural characteristics of Mn during cycling, as well as to quantify the Mn deposition on the counter electrode. By using an ether-based electrolyte instead of conventional carbonate electrolytes, we circumvent the formation of a surface Mn(II)-layer and Mn dissolution from LixMnO2. Consequently, we achieved an impressive ∼100% capacity retention for MnO2after 300 cycles at C/3. To create a lithium metal-lean full cell, we introduce hard carbon as the anode which is compatible with ether-based electrolytes. Commercial hard carbon delivers a specific capacity of ∼230 mAh g−1at 0.1 A g−1without plateau, indicating a surface-adsorption mechanism. The resulting manganese dioxide||hard carbon full cell exhibits stable cycling and high Coulombic efficiency. Our research provides a promising solution to develop cost-effective, scalable, and safe energy storage solutions using widely available manganese oxide and hard carbon materials.
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.
more » « less- Award ID(s):
- 2011924
- NSF-PAR ID:
- 10419318
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- SmartMat
- Volume:
- 4
- Issue:
- 5
- ISSN:
- 2766-8525
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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