Aqueous metal batteries represent a compelling avenue for energy storage solutions. Currently, research efforts are heavily concentrated on period 4 transition metals, starting from the prominent zinc to emerging candidates of iron, nickel, copper, and manganese. However, period 5 transition metals remain underexplored and poorly understood. Herein, we selected an underrepresented cadmium metal and investigated its fundamental plating chemistry, which showcases an unprecedented electrode performance, including low polarization (∼5 mV), long lifespan (4000 hours, 5.5 months), and exceptional plating efficiency. Notably, the efficiency approaches unity (99.92%) at 1.0 mA cm⁻² and 1.0 mA h cm⁻², and it retains 99.60–99.82% in more aggressive conditions (5–10 mA h cm⁻²; 0.25–0.50 mA cm⁻²). Surprisingly, such a performance is achieved without utilizing sophisticated electrolytes, additives, or surface treatments, which likely results from its suitable Cd²⁺/Cd redox potential, high resistance to hydrogen evolution, and densely stacked plate-like morphology. High-energy, high-rate, and long-cycling cadmium batteries have also been demonstrated. Our work contributes novel insights into the design of high-performance metal batteries.

中文翻译：

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释放镉电镀化学在低极化、长循环和超高效水系金属电池中的潜力


水性金属电池代表了一种引人注目的储能解决方案。目前，研究工作主要集中在第 4 周期过渡金属，从著名的锌到新兴的候选铁、镍、铜和锰。然而，第 5 周期过渡金属仍未得到充分探索和了解。在此，我们选择了一种代表性不足的镉金属，并研究了其基本电镀化学，其展示了前所未有的电极性能，包括低极化（∼5 mV）、长寿命（4000 小时，5.5 个月）和卓越的电镀效率。值得注意的是，效率在 1.0 mA cm ⁻² 和 1.0 mA h cm ⁻² 时接近一致 (99.92%)，并且在更恶劣的条件下 (5–10 mA) 保持 99.60–99.82% h 厘米 ⁻² ；0.25–0.50 mA 厘米 ⁻² ）。令人惊讶的是，这样的性能是在不使用复杂的电解质、添加剂或表面处理的情况下实现的，这可能是由于其合适的 Cd ²⁺ /Cd 氧化还原电位、高抗析氢性和密集堆叠的板状形态。高能量、高倍率、长循环的镉电池也已得到论证。我们的工作为高性能金属电池的设计提供了新颖的见解。