Vanadium-based cathodes have attracted great interest in aqueous zinc ion batteries (AZIBs) due to their large capacities, good rate performance and facile synthesis in large scale. However, their practical application is greatly hampered by vanadium dissolution issue in conventional dilute electrolytes. Herein, taking a new potassium vanadate K_0.486V₂O₅ (KVO) cathode with large interlayer spacing (~ 0.95 nm) and high capacity as an example, we propose that the cycle life of vanadates can be greatly upgraded in AZIBs by regulating the concentration of ZnCl₂ electrolyte, but with no need to approach “water-in-salt” threshold. With the optimized moderate concentration of 15 m ZnCl₂ electrolyte, the KVO exhibits the best cycling stability with ~ 95.02% capacity retention after 1400 cycles. We further design a novel sodium carboxymethyl cellulose (CMC)-moderate concentration ZnCl₂ gel electrolyte with high ionic conductivity of 10.08 mS cm⁻¹ for the first time and assemble a quasi-solid-state AZIB. This device is bendable with remarkable energy density (268.2 Wh kg⁻¹), excellent stability (97.35% after 2800 cycles), low self-discharge rate, and good environmental (temperature, pressure) suitability, and is capable of powering small electronics. The device also exhibits good electrochemical performance with high KVO mass loading (5 and 10 mg cm⁻²). Our work sheds light on the feasibility of using moderately concentrated electrolyte to address the stability issue of aqueous soluble electrode materials.

钒基正极因其大容量、良好的倍率性能和易于大规模合成而引起了水系锌离子电池（AZIBs）的极大兴趣。然而，它们的实际应用受到传统稀电解质中钒溶解问题的极大阻碍。在此，以新型钒酸钾 K _0.486 V ₂ O ₅ (KVO) 正极为例，该正极具有大层间距（~ 0.95 nm）和高容量，我们提出通过调节 AZIBs 的钒酸盐循环寿命可以大大提高ZnCl ₂电解质的浓度，但无需接近“盐包水”阈值。_{使用优化的 15 m ZnCl 2}中等浓度在电解质中，KVO 表现出最好的循环稳定性，在 1400 次循环后容量保持率约为 95.02%。我们进一步设计了一种新型羧甲基纤维素钠（CMC）-中等浓度ZnCl _{2凝胶电解质，具有10.08 mS cm} ^-1的高离子电导率，并组装了准固态AZIB。该器件可弯曲，具有显着的能量密度（268.2 Wh kg ^-1）、出色的稳定性（2800 次循环后为 97.35%）、低自放电率和良好的环境（温度、压力）适应性，能够为小型电子设备供电。该器件还表现出良好的电化学性能，具有高 KVO 质量负载（5 和 10 mg cm ^-2）。我们的工作揭示了使用中等浓度电解质解决水溶性电极材料稳定性问题的可行性。