Enhancing Zn‐Ion Battery Performances With Hydrogel Electrolytes: Synergistic Use of Mn‐Vanadate Positive and Metal–Organic Framework‐Derived CuO Negative Electrodes

This study explores the enhanced performance of Zn‐ion batteries using a SiO 2 /ZnSO 4 ‐based hydrogel electrolyte, compared with conventional absorbend glass mat (AGM) separator systems. The full cell employs Mn‐vanadate (MnVO) as the positive and metal–organic framework (MOF)‐derived copper oxides (CuO) as the negative electrodes. Mn‐doping stabilizes the vanadate layers and accelerates Zn 2+ diffusion, while the one‐dimensional channels in MOF‐derived CuO promote efficient Zn 2+ intercalation/deintercalation. Cyclic voltammetry indicates a diffusion‐controlled Faradaic mechanism for both electrodes, and impedance spectroscopy confirms high ionic diffusivity and electronic conductivity. Electrochemical measurements highlight excellent specific capacity and rate capability, validating the MnVO//CuO couple for practical applications. The 1.5 V gel‐based prismatic cell surpasses the 1.2 V AGM‐based pouch cell by offering a wider voltage window and reduced water loss. It delivers a specific capacity of 165 mAh g‐1 (@100 mA g −1 ), along with an energy density of 198 Wh kg‐1 (@20 W kg −1 ) and a power density of 616 W kg −1 (@178 Wh kg −1 ). Both the 1.2 pouch and 1.5 V prismatic cells were cycled 250 times at 500 mA g −1 , with capacity retentions of nearly 70% and 85%, respectively, and close to 99% Coulombic efficiency. Scalability, low cost, and environmental safety make MnVO//CuO chemistry a strong candidate for grid‐scale storage.