Given the high energy density, alkali metals are preferred in rechargeable batteries as anodes, however, with significant limitations such as dendrite growth and volume expansion, leading to poor cycle life and safety concerns. Herein a room‐temperature liquid alloy system is proposed as a possible solution for its self‐recovery property. Full extraction of alkali metal ions from the ternary alloy brings it back to the binary liquid eutectic, and thus enables a self‐healing process of the cracked or pulverized structure during cycling. A half‐cell discharge specific capacity of up to 706.0 mAh g−1in lithium‐ion battery and 222.3 mAh g−1for sodium‐ion battery can be delivered at 0.1C; at a high rate of 5C, a sizable capacity of over 400 mAh g−1for Li and 60 mAh g−1for Na could be retained. Li and Na ion full cells with considerable stability are demonstrated when pairing liquid metal with typical cathode materials, LiFePO4, and P2‐Na2/3[Ni1/3Mn2/3]O2. Remarkable cyclic durability, considerable theoretical capacity utilization, and reasonable rate stability present in this work allow this novel anode system to be a potential candidate for rechargeable alkali‐ion batteries.
Currently, there is considerable interest in developing advanced rechargeable batteries that boast efficient distribution of electricity and economic feasibility for use in large-scale energy storage systems. Rechargeable aqueous zinc batteries are promising alternatives to lithium-ion batteries in terms of rate performance, cost, and safety. In this investigation, we employ Cu3(HHTP)2, a two-dimensional (2D) conductive metal-organic framework (MOF) with large one-dimensional channels, as a zinc battery cathode. Owing to its unique structure, hydrated Zn2+ions which are inserted directly into the host structure, Cu3(HHTP)2, allow high diffusion rate and low interfacial resistance which enable the Cu3(HHTP)2cathode to follow the intercalation pseudocapacitance mechanism. Cu3(HHTP)2exhibits a high reversible capacity of 228 mAh g−1at 50 mA g−1. At a high current density of 4000 mA g−1(~18 C), 75.0% of the initial capacity is maintained after 500 cycles. These results provide key insights into high-performance, 2D conductive MOF designs for battery electrodes.
more » « less- Award ID(s):
- 1709888
- PAR ID:
- 10153537
- Publisher / Repository:
- Nature Publishing Group
- Date Published:
- Journal Name:
- Nature Communications
- Volume:
- 10
- Issue:
- 1
- ISSN:
- 2041-1723
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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