An Advanced High-Entropy Fluorophosphate Cathode for Sodium-Ion Batteries with Increased Working Voltage and Energy Density
© 2022 Wiley-VCH GmbH.
| Veröffentlicht in: | Advanced materials (Deerfield Beach, Fla.). - 1998. - 34(2022), 14 vom: 02. Apr., Seite e2110108 |
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| 1. Verfasser: | |
| Weitere Verfasser: | , , , , , , , , |
| Format: | Online-Aufsatz |
| Sprache: | English |
| Veröffentlicht: |
2022
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| Zugriff auf das übergeordnete Werk: | Advanced materials (Deerfield Beach, Fla.) |
| Schlagworte: | Journal Article cathodes high entropy phosphates sodium-ion batteries working voltage |
| Zusammenfassung: | © 2022 Wiley-VCH GmbH. Impossible voltage plateau regulation for the cathode materials with fixed active elemental center is a pressing issue hindering the development of Na-superionic-conductor (NASICON)-type Na3 V2 (PO4 )2 F3 (NVPF) cathodes in sodium-ion batteries (SIBs). Herein, a high-entropy substitution strategy, to alter the detailed crystal structure of NVPF without changing the central active V atom, is pioneeringly utilized, achieving simultaneous electronic conductivity enhancement and diffusion barrier reduction for Na+ , according to theoretical calculations. The as-prepared carbon-free high-entropy Na3 V1.9 (Ca,Mg,Al,Cr,Mn)0.1 (PO4 )2 F3 (HE-NVPF) cathode can deliver higher mean voltage of 3.81 V and more advantageous energy density up to 445.5 Wh kg-1 , which is attributed by the diverse transition-metal elemental substitution in high-entropy crystalline. More importantly, high-entropy introduction can help realize disordered rearrangement of Na+ at Na(2) active sites, thereby to refrain from unfavorable discharging behaviors at low-voltage region, further lifting up the mean working voltage to realize a full Na-ion storage at the high voltage plateau. Coupling with a hard carbon (HC) anode, HE-NVPF//HC SIB full cells can deliver high specific energy density of 326.8 Wh kg-1 at 5 C with the power density of 2178.9 W kg-1 . This route means the unlikely potential regulation in NASICON-type crystal with unchangeable active center becomes possible, inspiring new ideas on elevating the mean working voltage for SIB cathodes |
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| Beschreibung: | Date Revised 07.04.2022 published: Print-Electronic Citation Status PubMed-not-MEDLINE |
| ISSN: | 1521-4095 |
| DOI: | 10.1002/adma.202110108 |