The polyanion Li₇V₁₅O₃₆(CO₃) is a nanosized molecular cluster (≈1 nm in size), that has the potential to form an open host framework with a higher surface‐to‐bulk ratio than conventional transition metal oxide electrode materials. Herein, practical rechargeable Na‐ion batteries and symmetric Li‐ion batteries are demonstrated based on the polyoxovanadate Li₇V₁₅O₃₆(CO₃). The vanadium centers in {V₁₅O₃₆(CO₃)} do not all have the same V^IV/V redox potentials, which permits symmetric devices to be created from this material that exhibit battery‐like energy density and supercapacitor‐like power density. An ultrahigh specific power of 51.5 kW kg⁻¹ at 100 A g⁻¹ and a specific energy of 125 W h kg⁻¹ can be achieved, along with a long cycling life (>500 cycles). Moreover, electrochemical and theoretical studies reveal that {V₁₅O₃₆(CO₃)} also allows the transport of large cations, like Na⁺, and that it can serve as the cathode material for rechargeable Na‐ion batteries with a high specific capacity of 240 mA h g⁻¹ and a specific energy of 390 W h kg⁻¹ for the full Na‐ion battery. Finally, the polyoxometalate material from these electrochemical energy storage devices can be easily extracted from spent electrodes by simple treatment with water, providing a potential route to recycling of the redox active material.

中文翻译：

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基于聚氧钒酸盐的可充电钠离子电池和具有超级电容器类功率密度的对称锂离子电池的设计和性能

聚阴离子Li ₇ V ₁₅ O ₃₆（CO ₃）是一个纳米分子簇（大小约为1 nm），与传统的过渡金属氧化物电极相比，具有形成更高主体与本体比的开放主体构架的潜力。材料。在此，以聚氧钒酸盐Li ₇ V ₁₅ O ₃₆（CO ₃）为基础，演示了实用的Na-离子可充电电池和对称Li-离子电池。{V ₁₅ O ₃₆（CO ₃）}中的钒中心并非都具有相同的V ^{IV / V}氧化还原电势，可以使这种材料制成对称的器件，表现出类似于电池的能量密度和类似于超级电容器的功率密度。在100 A g ^{-1的条件下}，可以实现51.5 kW kg ^-1的超高比功率，在125 W h kg ^-1的比能下，具有较长的循环寿命（> 500个循环）。此外，电化学和理论研究表明，{V ₁₅ O ₃₆（CO ₃）}还可以传输较大的阳离子，例如Na ⁺，并且它可以用作具有高比容量的可再充电Na离子电池的阴极材料240 mA hg ^-1的比能量和390 W h kg ^-1的比能适用于完整的Na-ion电池。最后，通过简单的水处理，可以很容易地从废电极中提取这些电化学储能装置中的多金属氧酸盐材料，从而为氧化还原活性材料的回收提供了一条可能的途径。