Energy Material Advances
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2022
·
IF 0
Qiangqiang Zhang,Xing Shen,Quan Zhou,Kaixuan Li,Feixiang Ding,Yaxiang Lu,Junmei Zhao,Liquan Chen,Yong-Sheng Hu
Na-ion batteries (NIBs) have received significant interest as potential candidates for large-scale energy storage owing to the widespread distribution of sodium and superior low-temperature performance. However, their commercial application is usually hindered by the high production cost and inadequate performance for electrode materials, particularly for cathodes. Na3(VOPO4)2F (NVOPF) has been recognized as one of the most promising cathodes for high-energy NIBs owing to the high working voltage and energy density. Here, we report a facile highly efficient room-temperature solution protocol for large-scale synthesis of NVOPF cathode for NIBs. By simply regulating pH, NVOPF can be obtained, which delivered a discharge capacity of 120.2 mAh g-1 at 0.1 C and 72% capacity retention over 8000 cycles at 25 C. Besides, the kilogram-level NVOPF products have been synthesized, and 26650 cylindrical cells were fabricated, which exhibit excellent cycling stabilities, remarkable low-temperature performance with comparable safety features. We hope our findings could provide insights on the industrial application of NVOPF in NIBs.
研究领域:
材料科学
·
能源存储
✓ 已验证
DOI
Waste and Biomass Valorization
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2018
·Vol. 11
·期 5
·2201-2209
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IF 1.874
Tong Zizheng,Qi Yuruo,Zhao Junmei,Liu Lilu,Shen Xing,Liu Huizhou
In this work, a one-step hydrothermal strategy has been developed for the synthesis of carbon-coated Na 3 (VOPO 4 ) 2 F with the aid of biomass (e.g. glucose, fructose or starch), where biomass plays the key role of carbon source and reducing agent for reducing vanadium(V) to vanadium(IV). The effect of different biomass on the morphologies has been examined. Furthermore, the synthetic mechanism was deduced by investigating the impact of hydrothermal time on the synthesis. In addition, the vanadium oxidation state has been finally confirmed by XPS and UV–Vis. The as-synthesized carbon-coated Na 3 (VOPO 4 ) 2 F shows a superior long-term cycling performance, such as the capacity retentions are higher than 70% after 1400 cycles at a current rate of 5 C. The higher content of carbon will lead to the better rate capability. The present study suggests that the one-step hydrothermal technique using biomass as a reducing agent appears to be a facile and green low-cost approach to prepare the promising cathode material Na 3 (VOPO 4 ) 2 F.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
Joule
·
2018
·
IF 0
Yuruo Qi,Zizheng Tong,Junmei Zhao,Lu Ma,Tianpin Wu,Huizhou Liu,Chao Yang,Jun Lu,Yong-Sheng Hu
The large-scale application of rechargeable batteries in electric vehicles and energy-storage systems is still hindered by their high cost, particularly from the active materials. Here we proposed a concept of integration of extraction-separation and materials-preparation to further reduce the materials' cost. The power of this concept was demonstrated by the large-scale room-temperature synthesis (150 g per batch) of multi-shelled Na 3 (VOPO 4 ) 2 F microspheres based on in situ generated bubbles as soft templates. The as-prepared Na 3 (VOPO 4 ) 2 F shows superior rate capability with discharge capacity of 81 mAh g −1 at 15 C current rate and capacity retention of 70% after 3,000 cycles. Ex situ UV-vis was first employed to characterize the variation of oxidation state for vanadium during the charging and discharging process. This is the first report of a rapid and facile large-scale room-temperature controllable synthesis of Na 3 (VOPO 4 ) 2 F microspheres, and this approach could be extended to synthesize other similar compounds.
研究领域:
材料科学
·
电化学
·
储能
·
无机合成
✓ 已验证
DOI
ChemSusChem
·
2022
·Vol. 15
·期 15
·e202200817
·
IF 9.14
Jiarong He,Tao Tao,Fan Yang,Zhipeng Sun
Graphical Li? Na(h) . The intercalation mechanism and cathode electrolyte interphase property of Li-free polyanionic cathodes such as Na 3 V 2 (PO 4 ) 3 and Na 3 (VOPO 4 ) 2 F are systematically demonstrated. They show intriguing electrochemical performances for lithium-ion batteries towards a sustainable society due to the abundance of Na resource, providing appropriate crystallographic sites for Li + /Na + intercalation/deintercalation due to the existence of pillar Na + ion residing in the structure. Although lithium-ion batteries (LIBs) are promising towards high energy density and superior safety energy storage systems (ESS), severe depletion of Li reserve cannot meet the ever-growing demand for LIBs due to the uneven distribution and limited amount of Li resource. Li-free polyanionic cathodes, such as Na 3 V 2 (PO 4 ) 3 (NVP) and Na 3 (VOPO 4 ) 2 F (NVOPF), show intriguing electrochemical performances with prospective future for LIBs due to their appropriate crystallographic sites, robust host structure, and abundant Na resource. In this work, NVP and NVOPF were systematically investigated as cathodes for LIBs using different voltage windows of 2.5–4.3, 2.0–4.3, and 1.5–4.8 V, along with their electrochemical mechanisms, cathode electrolyte interphase properties, and electrode morphologies for comparison. Ex-situ X-ray diffraction, ex-situ X-ray photoelectron spectroscopy, and post-mortem scanning electron microscopy revealed that their mechanisms shifted from a predominant Na + intercalation/deintercalation in the first charging/discharging to a mixed Li + /Na + intercalation/deintercalation at the subsequent cycling. Due to the residual Na + acting as pillar in the structure, NVP and NVPF could serve as robust host framework, providing appropriate crystallographic sites for repeated Li + /Na + intercalation/deintercalation. NVP electrode delivered a higher discharge capacity of 107.6 mAh g −1 with superior capacity retention of 84.3 % after 1000 cycles (2.5–4.3 V, 100 mA g −1 ) than NVOPF electrode (97.3 mAh g −1 , 68.8 %). Electrode polarization and kinetic analysis manifested one energetically similar and two energetically nonequivalent crystallographic Na sites within the R c and I 4 /mmm polyanionic structure of NVP and NVOPF. This work comprehensively demonstrates the feasibility and prospect of sodium-based NVP and NVOPF polyanions serving as advanced Li-free cathodes for LIBs, which provides novel insights into seeking Li-free candidates as prospective cathodes for LIBs towards a more sustainable society and a cost-effective battery manufacturing system.
研究领域:
材料科学
·
能源存储与转换
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）