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Vanadium‐based cathode materials are being widely investigated in aqueous zinc‐ion batteries (ZIBs) due to their high specific capacity. However, poor cycling stability and low conductivity limit their practical applications. Herein, the hierarchical flower‐shaped (NH4)2V3O8/reduced graphene oxide (denoted as NVO/rGO) composite is designed to harvest high‐efficiency Zn storage. Benefiting from the stable layered structure of NVO, the prominent pseudocapacitance, and excellent conductivity of rGO, the NVO/rGO composite exhibits a high specific capacity of 375.3 mAh g−1 at 0.2 A g−1, excellent cycling stability of 265.0 mAh g−1 after 3700 cycles at 5.0 A g−1 (capacity retention over 95.3 %), and outstanding rate performance of 263.9 mAh g−1 at 10.0 A g−1 by using traditional coin cells. To further verify the practicability of the NVO/rGO cathode, flexible electrode and xanthan gum electrolyte are adopted to assemble quasi‐solid‐state ZIBs, which exhibit a great specific capacity of 185.0 mAh g−1 at 0.5 A g−1 and good stability under different bending angles with an impressive capacity retention of 92.2 % after cycling. This study illustrates that hierarchical flower‐shaped NVO/rGO has a promising potential as aqueous or quasi‐solid‐state ZIBs cathode and improves the application of vanadium‐based materials.Flower power: A hierarchical flower‐shaped (NH4)2V3O8/rGO composite is fabricated and applied in aqueous or quasi‐solid‐state zinc‐ion battery cathodes. Owing to the (NH4)2V3O8 stable layered structure and excellent conductivity of rGO, this composite exhibits good structure stability and enhanced electrochemical performance for Zn2+ storage. [ABSTRACT FROM AUTHOR]

Flexible rechargeable zinc‐ion batteries (ZIBs) have aroused tremendous attention owing to the good safety and abundant reserves, making it one of the most promising alternatives for novel energy storage devices. Herein, flexible, free‐standing hybrid films with a three‐dimensional interlaced network are reported for ZIBs. The flexible and pliable VO2/MXene hybrid films deliver a high specific capacity of 228.5 mAh g−1 at 0.2 A g−1 and display a reversible capacity over 126.6 mAh g−1 after 700 cycles at 2 A g−1. More impressively, the flexible electrode also shows exciting mechanical flexibility and outstanding Zn2+ storage capability with a moderate capacity retention of 72.1 % after 2500 cycles at 5 A g−1 in quasi‐solid‐state ZIBs. The special structure can boost the diffusion pathway of Zn2+ and effectively stabilize the structure of the electrode upon cycling. This work also evidences that the flexible VO2/MXene hybrid films own an immense potential for portable and flexible equipment. [ABSTRACT FROM AUTHOR]