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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.
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A Self‐Sodiophilic Carbon Host Promotes the Cyclability of Sodium Anode
Abstract Benefiting from abundant resource reserves and considerable theoretical capacity, sodium (Na) metal is a strong anode candidate for low‐cost, large‐scale energy storage applications. However, extensive volume change and mossy/dendritic growth during Na electrodeposition have impeded the practical application of Na metal batteries. Herein, a self‐sodiophilic carbon host, lignin‐derived carbon nanofiber (LCNF), is reported to accommodate Na metal through an infiltration method. Na metal is completely encapsulated in the 3D space of the LCNF host, where the strong interaction between LCNF and Na metal is mediated by the self‐sodiophilic sites. The resulting LCNF@Na electrode delivers good cycling stability with a low voltage hysteresis and a dendrite‐free morphology in commercial carbonate‐based electrolytes. When interfaced with O3‐NaNi0.33Mn0.33Fe0.33O2and P2‐Na0.7Ni0.33Mn0.55Fe0.1Ti0.02O2cathodes in full cell Na metal batteries, the LCNF@Na electrode enables high capacity retentions, long cycle life, and good rate capability. Even in a “lean” Na anode environment, the full cells can still deliver good electrochemical performance. The overall stable battery performance, based on a self‐sodiophilic, biomass‐derived carbon host, illuminates a promising path towards enabling low‐cost Na metal batteries.
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- Award ID(s):
- 1912885
- PAR ID:
- 10453753
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Functional Materials
- Volume:
- 31
- Issue:
- 9
- ISSN:
- 1616-301X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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