Sluggish kinetics and poor reversibility of cathode chemistry is the major challenge for magnesium batteries to achieve high volumetric capacity. Introduction of the cuprous ion (Cu⁺) as a charge carrier can decouple the magnesiation related energy storage from the cathode electrochemistry. Cu⁺ is generated from a fast equilibrium between copper selenide electrode and Mg electrolyte during standing time, rather than in the electrochemical process. A reversible chemical magnesiation/de‐magnesiation can be driven by this solid/liquid equilibrium. During a typical discharge process, Cu⁺ is reduced to Cu and drives the equilibrium to promote the magnesiation process. The reversible Cu to Cu⁺ redox promotes the recharge process. This novel Cu⁺ mediated cathode chemistry of Mg battery leads to a high reversible areal capacity of 12.5 mAh cm⁻² with high mass loading (49.1 mg cm⁻²) of the electrode. 80 % capacity retention can be achieved for 200 cycles after a conditioning process.

中文翻译：

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用于镁电池的高度可逆的亚铜介导的阴极化学。

动力学缓慢和阴极化学的可逆性差是镁电池实现高容量的主要挑战。引入亚铜离子（Cu ⁺）作为电荷载体可以使与放大倍数相关的能量存储与阴极电化学分离。Cu ⁺是由硒化铜电极和Mg电解质在静置时间内而不是在电化学过程中快速平衡产生的。这种固/液平衡可以驱动可逆的化学放大/缩小。在典型的放电过程中，Cu ⁺还原为Cu并推动平衡，从而促进了放大过程。可逆的铜到铜⁺氧化还原促进充电过程。Mg电池的这种新颖的Cu ⁺介导的阴极化学性质导致电极的高质量负载（49.1 mg cm ^-2）的高可逆面容量为12.5 mAh cm ^-2。调理过程完成200个循环后，可获得80％的容量保持率。