Aqueous zinc-ion batteries (ZIBs) have attracted significant attention for grid-scale energy applications due to their low cost, intrinsic safety, and environmental friendliness. However, the energy density of current ZIBs is impeded by unsatisfactory performance of cathodes, due to their limited areal capacity and low active material loading, especially at extreme environments. Herein, an electrochemical activation strategy is put forward to build high energy density ZIBs by designing a flexible cathode composed of NH₄⁺ pillared ammonium vanadate nanosheets on carbon cloth (NVMCE@CC). The electrochemical activation process with high anodic potential (> 1.5 V vs. Zn²⁺/Zn) guarantees the effective conversion of low-valent to high-valent vanadium and promotes the utilization of large amounts of vanadium elements in the NVMCE@CC composite. Meanwhile, the pillared NH₄⁺ ions expand the interlayer spacing and enhance the structural integrity through the hydrogen bonding between NH₄⁺ and V-O framework. Consequently, the activated NVMCE@CC cathode with a high mass-loading of ∼5.2 mg cm⁻² delivers large areal capacity (∼1.74 mAh cm⁻² at 1 mA cm⁻²) and superior cycling stability (capacity retention of 72.1% after 1500 cycles). Importantly, the flexible cathode shows admirable capacities of 0.52 mAh cm⁻² at 60 °C and 0.55 mAh cm⁻² at − 10 °C, respectively. Moreover, the NVMCE@CC//Zn@CC quasi-solid-state battery demonstrates excellent safety performance and performs well in extreme situations, including bending, cutting, hammering, and washing. This work provides enlightenment for the development of large-areal-capacity vanadium-based cathode materials for practical ZIBs.

水系锌离子电池（ZIB）由于其低成本、本质安全和环境友好而在电网规模能源应用中引起了广泛关注。然而，由于其面积容量有限和活性材料负载量低，特别是在极端环境下，当前ZIB的能量密度受到阴极性能不理想的阻碍。在此，提出了一种电化学活化策略，通过设计由碳布上的_{NH 4} ⁺柱撑钒酸铵纳米片组成的柔性阴极（NVMCE@CC）来构建高能量密度ZIB。高阳极电位（> 1.5 V vs. Zn ^2+）的电化学活化过程/Zn）保证了低价钒向高价钒的有效转化，促进了NVMCE@CC复合材料中大量钒元素的利用。同时，柱状NH ₄ ^{+离子通过NH} ₄ ⁺和VO骨架之间的氢键扩大了层间距并增强了结构完整性。^{因此，具有〜5.2 mg cm -2}高质量负载的活化NVMCE@CC正极具有大面积容量（1 mA cm ^{-2时〜1.74 mAh cm -2}）和优异的循环稳定性（循环后容量保持率为72.1％） 1500 个周期）。重要的是，柔性阴极显示出令人惊叹的0.52 mAh cm ^-2容量分别在 60 °C 和 0.55 mAh cm ^-2在 - 10 °C 时。此外，NVMCE@CC//Zn@CC准固态电池表现出优异的安全性能，在弯曲、切割、锤击、清洗等极端情况下表现良好。该工作为实用ZIBs大面积容量钒基正极材料的开发提供了启示。