Multi‐Cation Synergy in Medium‐Entropy Spinel Oxide for Practical Zn‐Ion Pouch Cells
Xinhua Zheng, Rui Zhang, Fengchun Wei, Song Wu, Bibo Han, Zhigang Yu, Shaoyi Shen, Meng Liu, Pengxian Lu, Yupeng Shi, Fang He, Faxing Wang, Shikai Liu, Yuping WuABSTRACT
Manganese oxide cathodes for aqueous zinc‐ion batteries (AZIBs) are promising yet hindered by dissolution, structural collapse, and disproportionation, limiting their practical application. Herein, we report a multi‐cation synergistic medium‐entropy oxide (MEO) cathode with a spinel structure, Zn 0.86 Co 0.28 Ni 0.04 Cu 0.03 Mn 2 O 4 (ZCNCMO), designed to overcome these limitations. Theoretical and experimental analyses demonstrate that integrating multiple cations into a single spinel lattice leverages entropy stabilization to suppress elemental segregation, lattice distortion, and active species dissolution, thereby preserving structural integrity during cycling. As a result, the Zn‐ZCNCMO battery delivers a specific capacity of 520 mAh g −1 at 0.5 A g −1 , and retains a capacity retention of 98.3% after 2600 cycles at 2 A g −1 . The pouch cell delivers excellent stability over 1000 cycles and exhibits an energy density of 239.9 Wh kg −1 based on active materials and practically 56.3 Wh kg −1 , which is also integrated with solar and wind energy to power consumer electronics with exceptional safety under nail‐penetration and cutting tests.