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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 great attention due to their high theoretical energy density. The rapid redox conversion of lithium polysulfides (LiPS) is effective for solving the serious shuttle effect and improving the utilization of active materials. The functional design of the separator interface with fast charge transfer and active catalytic sites is desirable for accelerating the conversion of intermediates. Herein, a graphene‐wrapped MnCO3 nanowire (G@MC) was prepared and utilized to engineer the separator interface. G@MC with active Mn2+ sites can effectively anchor the LiPS by forming the Mn−S chemical bond according to our theoretical calculation results. In addition, the catalytic Mn2+ sites and conductive graphene layer of G@MC could accelerate the reversible conversion of LiPS via the spontaneous “self‐redox” reaction and the rapid electron transfer in electrochemical process. As a result, the G@MC‐based battery exhibits only 0.038 % capacity decay (per cycle) after 1000 cycles at 2.0 C. This work affords new insights for designing the integrated functional interface for stable Li−S batteries.

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