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DOI: 10.1002/aenm.201702463 other secondary batteries.[6–8] However, LIBs are too expensive to scale up for the processing cost resulted from the limited lithium resources, and SIBs are subjected to complicated issues of safety as well as environmental issues.[9–12] So, it is an urgent challenge for exploring new energy storage systems. As an alternative, rechargeable aqueous Zn-ion batteries (ZIBs) have received incremental attention owing to the following advantages, including low cost, safety, and environmentally friendly.[13] Meanwhile, using aqueous electrolyte to replace the organic electrolyte is of great significance for reducing the cost and environmental pollution.[14] However, it is difficult to find suitable cathode material as the host for the intercalation of Zn2+ owing to the high polarization of Zn2+ as well as the narrow applicable voltage range, which is limited by the water splitting in the aqueous battery system.[15] Typically, polymorphs of MnO2 (α-, γ-phase) are highly attractive as the cathode material because of the tunnel structure suiting for the intercalation of Zn2+ and a matched potential within the stable range of water. Some results, based on the reversible intercalation of Zn2+, have been reported in recent years, and they show either limited specific capacity or poor cycling performance.[16–19] Recently, the MnO2 nanofiber electrode, reported by Liu and co-workers, shows high capacity and excellent cycling performance.[20] However, the rate performance is not high enough due to the sluggish reaction dynamics of conversion reaction. Prussian blue analogues, including of zinc hexacyanoferrate and copper hexacyanoferrate, are another class of cathode materials, which show limited specific capacity as well as poor cyclic stability.[21–23] Until very recently, vanadiumbased materials are explored for reversible Zn2+ intercalation.[24] Nazar and co-workers reported a bilayered Zn0.25V2O5·nH2O cathode, which shows a high-capacity and long-life performance.[25] However, the development of ZIBs is in the primary stage, some new cathode materials should also be explored to enhance the energy density as well as cycle life for ZIBs. Over the past decades, layered vanadium oxides have been applied as electrode materials for LIBs or SIBs due to their low cost and high capacities.[26,27] Generally, the bulk vanadium oxides suffer from a rapid capacity fading resulting from low electronic conductivity, poor structural stability during the ion de/intercalation.[28] Recent studies show that interlayer metal ions (MxVnOm, M = metal ion) can act as pillars to increase the Aqueous Zn-ion batteries (ZIBs) have received incremental attention because of their cost-effectiveness and the materials abundance. They are a promising choice for large-scale energy storage applications. However, developing suitable cathode materials for ZIBs remains a great challenge. In this work, pioneering work on the designing and construction of aqueous Zn//Na0.33V2O5 batteries is reported. The Na0.33V2O5 (NVO) electrode delivers a high capacity of 367.1 mA h g−1 at 0.1 A g−1, and exhibits long-term cyclic stability with a capacity retention over 93% for 1000 cycles. The improvement of electrical conductivity, resulting from the intercalation of sodium ions between the [V4O12]n layers, is demonstrated by single nanowire device. Furthermore, the reversible intercalation reaction mechanism is confirmed by X-ray diffraction, Raman, X-ray photoelectron spectroscopy, scanning electron microscopy, and transmission electron microscopy analysis. The outstanding performance can be attributed to the stable layered structure and high conductivity of NVO. This work also indicates that layered structural materials show great potential as the cathode of ZIBs, and the indigenous ions can act as pillars to stabilize the layered structure, thereby ensuring an enhanced cycling stability. Zinc Ion Batteries