Rechargeable aqueous zinc ion batteries (ZIBs), with the easy operation, cost effectiveness, and high safety, are emerging candidates for high-energy wearable/portable energy storage systems. Unfortunately, the unsatisfactory energy density and undesired long-term cycling performance of the cathode hinder the development of ZIBs. Here, we report the chemical pre-intercalation of a small amount of calcium ions into V₂O₅ as the cathode material. The cathode of Ca_0.04V₂O₅•1.74H₂O (CVO) was demonstrated to have a high specific capacity of 400 mA h g⁻¹ at the current density of 0.05 A g⁻¹ and 187 mA h g⁻¹ at 10 A g⁻¹, along with impressive capacity retention (100% capacity retention at 10 A g⁻¹ for 3,000 cycles). Meanwhile, the CVO// Zn battery exhibits a high energy density of 308 Wh kg⁻¹ and a power density of 467 W kg⁻¹ at 0.5 A g⁻¹. The superior performance originates from the pinning effect of the calcium ions and the lubricating effect of the structural water. The energy storage mechanism of the CVO cathode was also investigated in detail. The new phase (Zn₃(OH)₂V₂O₇•2H₂O) generated upon cycling participates in the electrochemical reaction and thus contributes to the excellent electrochemical performance. The small amount of Ca²⁺ pre-inserted into the interlayer of V₂O₅ sheds light on constructing cathodes with high energy density for ZIBs.

具有易于操作，成本效益和高安全性的可再充电含水锌离子电池（ZIB）是高能量可穿戴/便携式储能系统的新兴候选产品。不幸的是，不令人满意的能量密度和不希望的阴极长期循环性能阻碍了ZIBs的发展。在这里，我们报告了将少量钙离子化学预嵌入到作为阴极材料的V ₂ O ₅中。Ca _0.04 V ₂ O ₅ •1.74H ₂ O（CVO）的阴极在电流密度为0.05 A g ^-1和187 mA hg ^-1时具有400 mA hg ^-1的高比容量在10 A g ^-1时具有出色的容量保持能力（在10 A g ^-1时100％容量保持3,000个循环）。同时，CVO // Zn电池在0.5 A g ^-1下表现出308 Wh kg ^-1的高能量密度和467 W kg ^-1的功率密度。优异的性能源于钙离子的钉扎作用和结构水的润滑作用。还对CVO阴极的储能机理进行了详细研究。新相（Zn ₃（OH）₂ V ₂ O ₇ •2H ₂循环时产生的O）参与电化学反应，因此有助于优异的电化学性能。预插入到V ₂ O ₅中间层中的少量Ca ^2+可以为构建具有高能量密度的ZIBs阴极提供照明。