Rechargeable zinc-ion batteries (ZIBs) have shown great potential for grids-level energy storage system. However, the lack of desirable and stable cathode materials remains challenging. Herein, Sn_1.5V₂O₇(OH)₂•3.3H₂O, in which pyrovanadate V₂O₇⁴⁻ group pillared with Sn oxide layer, is developed as an advanced cathode for ZIBs and a hidden reaction mechanism in SnVO cathode through in-situ Raman and ex-situ XANEs, involves the opening of V˭O edge bonding and formation of Sn–O–V bonding, which leads to charge screening effect and facilitates the fast diffusion kinetics for zinc ions, as quantitatively verified by kinetic analysis. Additionally, the tetravalent Sn ions bring about stronger ionic bonds, binding to pyrovanadate V₂O₇⁴⁻ group and leading to good stability in the pyrovanadate framework, which guarantee the cycling stability. As a result, the as-prepared SnVO shows long cycling life as well as excellent rate capability. We demonstrate that, even cycled at high current of 10 A/g, the SnVO cathode can still retain a capacity of 130 mAh/g for over 500 cycles, indicating remarkable high capacity at high rate. Our findings reveal that the tetravalent tin ions have a strong beneficial effect on the battery performance of the layered-structure cathode materials. It is believed that our study would boost further studies in other multi-valent rechargeable batteries.

可充电锌离子电池（ZIB）在电网级储能系统中显示出巨大潜力。然而，缺少合乎需要的和稳定的阴极材料仍然具有挑战性。在此，开发了以Sn氧化物层为柱基的吡咯烷酸盐V ₂ O ₇ ^4-的Sn _1.5 V ₂ O ₇（OH）₂ •3.3H ₂ O作为用于ZIBs的高级阴极和SnVO阴极中的隐藏反应机理而开发。通过原地拉曼和异地XANEs涉及V˭O边缘键的打开和Sn–O–V键的形成，这导致了电荷屏蔽效应，并促进了锌离子的快速扩散动力学，这已通过动力学分析进行了定量验证。另外，四价锡离子带来更强的离子键，与丙酮酸钒₂ V ₇ O ^4-结合并在焦钒酸盐骨架中产生良好的稳定性，从而保证了循环稳定性。结果，所制备的SnVO显示出长的循环寿命以及优异的速率能力。我们证明，即使以10 A / g的高电流循环，SnVO阴极仍可以在500个循环中保持130 mAh / g的容量，表明在高速率下具有显着的高容量。我们的发现表明，四价锡离子对层状阴极材料的电池性能具有很强的有益作用。相信我们的研究将促进其他多价可充电电池的进一步研究。