High-Entropy\nMultiple-Anion Aqueous Electrolytes for\nLong-Life Zn-Metal Anodes

Aqueous\nzinc-ion batteries (AZIBs) hold great promise for large-scale\nenergy storage applications, however, their practical use is significantly\nhindered by issues such as zinc dendrite growth and hydrogen evolution.\nTo address these challenges, we propose a high-entropy (HE) electrolyte\ndesign strategy that incorporates multiple zinc salts, aimed at enhancing\nion kinetics and improving the electrochemical stability of the electrolyte.\nThe interactions between multiple anions and Zn<sup>2+</sup> increase\nthe complexity of the solvation structure, resulting in smaller ion\nclusters while maintaining weakly anion-rich solvation structures.\nThis leads to improved ion mobility and the formation of robust interphase\nlayers on the electrode–electrolyte interface. Moreover, the\nHE electrolyte effectively suppresses hydrogen evolution and corrosion\nside reactions while facilitating uniform and reversible Zn plating/stripping\nprocesses. Impressively, the optimized electrolyte enables dendrite-free\nZn plating/stripping for over 3000 h in symmetric cells and achieves\na high Coulombic efficiency of 99.5% at 10 mA cm<sup>–2</sup> in asymmetric cells. Inspiringly, full cells paired with Ca-VO<sub>2</sub> cathodes demonstrate excellent performance, retaining 81.5%\nof the initial capacity over 1800 cycles at 5 A g<sup>–1</sup>. These significant findings highlight the potential of this electrolyte\ndesign strategy to improve the performance and lifespan of Zn-metal\nanodes in AZIBs.