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Sodium ion batteries are an emerging candidate to replace lithium ion batteries in large-scale electrical energy storage systems due to the abundance and widespread distribution of sodium. Despite the growing interest, the development of high-performance sodium cathode materials remains a challenge. In particular, polyanionic compounds are considered as a strong cathode candidate owing to their better cycling stability, a flatter voltage profile, and stronger thermal stability compared to other cathode materials. Here, we report the rational design of a biomimetic bone-inspired polyanionic Na3V2(PO4)3-reduced graphene oxide composite (BI-NVP) cathode that achieves ultrahigh rate charging and ultralong cycling life in a sodium ion battery. At a charging rate of 1 C, BI-NVP delivers 97% of its theoretical capacity and is able to retain a voltage plateau even at the ultra-high rate of 200 C. It also shows long cycling life with capacity retention of 91% after 10 000 cycles at 50 C. The sodium ion battery cells with a BI-NVP cathode and Na metal anode were able to deliver a maximum specific energy of 350 W h kg−1 and maximum specific power of 154 kW kg−1. In situ and postmortem analyses of cycled BI-NVP (including by Raman and XRD spectra) HRTEM, and STEM-EELS, indicate highly reversible dilation–contraction, negligible electrode pulverization, and a stable NVP-reduced graphene oxide layer interface. The results presented here provide a rational and biomimetic material design for the electrode architecture for ultrahigh power and ultralong cyclability of the sodium ion battery full cells when paired with a sodium metal anode.
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One-Pot Aqueous Synthesis of Hierarchical Na3V2(PO4)3 Particles for High-Performance Sodium Batteries
Abstract Intermittent renewable energy sources can mitigate climate change, but they require high-performance, reliable batteries. The widely used lithium-ion batteries contain Li, Co, and Ni, and the growing demand for these elements, together with their relatively limited sources, has raised concerns about their supply chain stability. Sodium-ion batteries have become an economical alternative. Sodium vanadium phosphate, Na3V2(PO4)3 (NVP), is a compelling candidate with high stability and ionic conductivity due to its polyanionic sodium superionic conductor (NASICON) structure. However, NVP suffers from poor electronic conductivity and requires hierarchical morphology to allow facile ion and electron transfer. Spray-drying has been used to achieve hierarchical secondary particle structures, but the foremost reported NVP syntheses rely on either flammable/toxic organic solvents or expensive nanocarbon additives. In this study, we spray-dry an aqueous suspension without using expensive carbon additives. The obtained NVP sodium-ion half cells showed very high reversible capacity (114.7 mAh g-1 at 0.2C), high rate capability (80.8% capacity retention at 30C), and stable cycling performance (96.7% capacity retention after 1,500 cycles at 10C). This superior performance demonstrates the great promise for NVP batteries as an alternative energy storage option to traditional lithium-ion batteries.
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- PAR ID:
- 10600487
- Publisher / Repository:
- The Electrochemical Society
- Date Published:
- Journal Name:
- Journal of The Electrochemical Society
- ISSN:
- 0013-4651
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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