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The ultrafast charging property plays a significant role in achieving high-rate performance in a working aqueous battery system. However, the fast charging process usually causes irreversible structure evolution, thereby resulting into a dramatic capacity decay at high current densities. Herein, proton-substituted HNaV6O16·4H2O (HNVO) was fabricated via a facile hydrothermal method and utilized as the cathode of zinc ion batteries. The proton can not only serve as the interlayer pillar to stabilize the layer structure but also improve the utilization of active materials. In addition, the preinserted H+ is also beneficial for accelerating the kinetics of the charge carrier and reducing the electrochemical irreversibility, achieving a high-rate performance. In our case, the Zn/HNVO battery delivers 331.3 mA h g–1 (charged at 10.0 A g–1) and maintains 333.2 mA h g–1 (discharged at 1.0 A g–1) with a high Coulombic efficiency of 100.5%. Importantly, it also delivers an ultralong cycling stability with almost no capacity decay (10 000 cycles at 20 A g–1). This design of the cathode provides a new insight for developing ultrafast-charging aqueous battery systems.

Manganese dioxide (MnO2) as one of the promising cathode candidates has attracted great attention in aqueous zinc ion battery (ZIB). However, the undesirable dissolving of Mn2+ and the sluggish kinetic...

Lithium‐sulfur (Li‐S) batteries have attracted attention due to their high theoretical energy density, natural abundance, and low cost. However, the diffusion of polysulfides decreases the utilization and further degrades the battery's life. We have successfully fabricated a defect‐rich layered sodium vanadium oxide with proton doping (HNVO) nanobelt and used it as the functional interface layer on the separator in Li‐S batteries. Benefiting from the abundant defects of NVO and the catalytic activity of metal vanadium in the electrochemical process, the shuttle of polysulfides was greatly decreased by reversible chemical adsorption. Moreover, the extra graphene layer contributes to accelerating the charge carrier at high current densities. Therefore, a Li‐S battery with G@HNVO delivers a high capacity of 1494.8 mAh g−1 at 0.2 C and a superior cycling stability over 700 cycles at 1 C. This work provides an effective strategy for designing the electrode/separator interface layer to achieve high‐performance Li‐S batteries.

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