通过简单的溶胶-凝胶辅助静电纺丝法得到(113)晶面优势导向的Na_3V_2(PO_4)_3/C钠离子电池正极材料,并通过对比最佳纺丝条件下分别用聚乙烯吡咯烷酮(PVP)和聚氧化乙烯(PEO)作为晶面导向剂制备的两种Na_3V_2(PO_4)_3电极材料的电化学性能...通过简单的溶胶-凝胶辅助静电纺丝法得到(113)晶面优势导向的Na_3V_2(PO_4)_3/C钠离子电池正极材料,并通过对比最佳纺丝条件下分别用聚乙烯吡咯烷酮(PVP)和聚氧化乙烯(PEO)作为晶面导向剂制备的两种Na_3V_2(PO_4)_3电极材料的电化学性能,证明静电纺丝有利于实现Na_3V_2(PO_4)_3(113)晶面择优取向。在相同的电流密度(0.1 C)下,NVP-PVP和NVP-PEO的首周放电比容量分别为112.5 m A·h/g和96.3 m A·h/g,电池循环50周后,NVP-PVP仍然有98.1 m A·h/g的可逆容量保持,NVP-PEO仅仅只剩下34 m A·h/g的可逆容量保持,而即使循环100周后,NVP-PVP的可逆容量仍然在88.2 m A·h/g。结果表明,PVP静电纺丝有利于构建特定的纳米纤维结构和均一的导电碳网络骨架,进而提升主体材料Na_3V_2(PO_4)_3的电化学性能。展开更多
NASICON (Na-super-ionic-conductors)-structured materials have attracted extensive research interest due to their great application potential in secondary batteries. However, the mechanism of capacity fading for NASICO...NASICON (Na-super-ionic-conductors)-structured materials have attracted extensive research interest due to their great application potential in secondary batteries. However, the mechanism of capacity fading for NASICON-structured electrode materials has been rarely studied. In this paper, we synthesized the NASICON-structured Na3V2(PO4)3/C composite by simple sol-gel and high-temperature solid-phase method and investigated its electrochemical performance in Na-Zn hybrid aqueous rechargeable batteries. After characterizing the structure, morphology and composition variations as well as the interfacial resistance changes of Na3V2(PO4)3/C cathode during cycling, we propose a mechanical and interfacial degradation mechanism for capacity fading of NASICON-structured Na3V2(PO4)3/C in Na-Zn hybrid aqueous rechargeable batteries. This work will shed light on enhancing the mechanical and in terfacial stability of NASICON-structured Na3V2(PO4)3/C in Na-Zn hybrid aqueous rechargeable batteries.展开更多
Sodium-ion batteries （SIBs） have attracted increasing attention in the past decades, because of high over-all abundance of precursors, their even geographical distribution, and low cost. Na3V2（PO4）3 （NVP）, atypi...Sodium-ion batteries （SIBs） have attracted increasing attention in the past decades, because of high over-all abundance of precursors, their even geographical distribution, and low cost. Na3V2（PO4）3 （NVP）, atypical sodium super ion conductor （NASlCON）-based electrode material, exhibits pronounced structuralstability, exceptionally high ion conductivity, rendering it a most promising electrode for sodium storage.However. the comparatively low electronic conductivity makes the theoretical capacity of NVP cannot befully accessible even at comparatively low rates, presenting a major drawback for further practical ap-plications, especially when high rate capability is especially important. Thus, many endeavors have beenconformed to increase the surface and intrinsic electrical conductivity of NVP by coating the active mate-rials with a conductive carbon layer, downsizing the NVP particles, combining the NVP particle with vari-ous carbon materials and ion doping strategy. In this review, to get a better understanding on the sodiumstorage in NVP, we firstly present 4 distinct crystal structures in the temperature range of-30℃-225℃ namely α-NVP, β-NVP, β′-NVP and γ-NVP. Moreover, we give an overview of recent approaches to en-hance the surface electrical conductivity and intrinsic electrical conductivity of NVP. Finally, some poten-tial applications of NVP such as in all-climate environment and PHEV, EV fields have been prospected.展开更多
文摘通过简单的溶胶-凝胶辅助静电纺丝法得到(113)晶面优势导向的Na_3V_2(PO_4)_3/C钠离子电池正极材料,并通过对比最佳纺丝条件下分别用聚乙烯吡咯烷酮(PVP)和聚氧化乙烯(PEO)作为晶面导向剂制备的两种Na_3V_2(PO_4)_3电极材料的电化学性能,证明静电纺丝有利于实现Na_3V_2(PO_4)_3(113)晶面择优取向。在相同的电流密度(0.1 C)下,NVP-PVP和NVP-PEO的首周放电比容量分别为112.5 m A·h/g和96.3 m A·h/g,电池循环50周后,NVP-PVP仍然有98.1 m A·h/g的可逆容量保持,NVP-PEO仅仅只剩下34 m A·h/g的可逆容量保持,而即使循环100周后,NVP-PVP的可逆容量仍然在88.2 m A·h/g。结果表明,PVP静电纺丝有利于构建特定的纳米纤维结构和均一的导电碳网络骨架,进而提升主体材料Na_3V_2(PO_4)_3的电化学性能。
基金financially supported by"135"Projects Fund of CAS-QIBEBT Director Innovation Foundationthe Strategic Priority Research Program of the Chinese Academy of Sciences(Grant no.XDA09010105)+4 种基金the National Natural Science Foundation of China(Grant no.51502319)the Think-Tank Mutual Fund of Qingdao Energy Storage Industry Scientific Researchthe Qingdao Science and Technology Program(17-1-1-26-jch)the Youth Innovation Promotion Association CAS(No.2017253)Qingdao Key Lab of Solar Energy Utilization&Energy Storage Technology
文摘NASICON (Na-super-ionic-conductors)-structured materials have attracted extensive research interest due to their great application potential in secondary batteries. However, the mechanism of capacity fading for NASICON-structured electrode materials has been rarely studied. In this paper, we synthesized the NASICON-structured Na3V2(PO4)3/C composite by simple sol-gel and high-temperature solid-phase method and investigated its electrochemical performance in Na-Zn hybrid aqueous rechargeable batteries. After characterizing the structure, morphology and composition variations as well as the interfacial resistance changes of Na3V2(PO4)3/C cathode during cycling, we propose a mechanical and interfacial degradation mechanism for capacity fading of NASICON-structured Na3V2(PO4)3/C in Na-Zn hybrid aqueous rechargeable batteries. This work will shed light on enhancing the mechanical and in terfacial stability of NASICON-structured Na3V2(PO4)3/C in Na-Zn hybrid aqueous rechargeable batteries.
基金financial support from the National Natural Science Foundation of China (No.21501171,51403209,21406221,51177156/E0712)
文摘Sodium-ion batteries （SIBs） have attracted increasing attention in the past decades, because of high over-all abundance of precursors, their even geographical distribution, and low cost. Na3V2（PO4）3 （NVP）, atypical sodium super ion conductor （NASlCON）-based electrode material, exhibits pronounced structuralstability, exceptionally high ion conductivity, rendering it a most promising electrode for sodium storage.However. the comparatively low electronic conductivity makes the theoretical capacity of NVP cannot befully accessible even at comparatively low rates, presenting a major drawback for further practical ap-plications, especially when high rate capability is especially important. Thus, many endeavors have beenconformed to increase the surface and intrinsic electrical conductivity of NVP by coating the active mate-rials with a conductive carbon layer, downsizing the NVP particles, combining the NVP particle with vari-ous carbon materials and ion doping strategy. In this review, to get a better understanding on the sodiumstorage in NVP, we firstly present 4 distinct crystal structures in the temperature range of-30℃-225℃ namely α-NVP, β-NVP, β′-NVP and γ-NVP. Moreover, we give an overview of recent approaches to en-hance the surface electrical conductivity and intrinsic electrical conductivity of NVP. Finally, some poten-tial applications of NVP such as in all-climate environment and PHEV, EV fields have been prospected.
