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Zinc metal is abundant in nature, non‐toxic, harmless, and cheap. Zinc‐ion batteries (ZIBs) have also emerged as the times require, which has attracted scholars′ research interest. In the zinc‐ion batteries, the cathode material is indispensable. Manganese oxides are widely used in electrode materials because of their various valence states (+2, +3, +4, +7). ZnMn2O4 (ZMO) is a mixed metal oxide with a spinel structure similar to LiMn2O4. Due to the synergistic effect of Zn and Mn, it has the advantages of high theoretical capacity. In recent years, researchers have gradually applied ZnMn2O4 to zinc ion batteries. In order to obtain high‐energy‐density zinc ion batteries, it is also very important to match electrolytes with a wide operating voltage window and develop a highly reversible anode. In the first instance, we investigate the research progress of spinel ZnMn2O4 as a reliable candidate material for zinc ion batteries. Later on, we review the optimization and modification measures of anode and electrolyte to improve the electrochemical properties of spinel ZnMn2O4. On this basis, we propose the reasonable research direction and development prospects for this material. It is hoped that there will be a help to researchers in this field.

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Zinc manganese spinel composite oxide ZnMn2O4 is an important inorganic material, which is rich in natural resources and environment-friendly. Herein, pure phase ZnMn2O4 was prepared by a simple sol-gel process as cathode material for zinc ion batteries. In order to improve the cycle performance of the material while maintaining the capacity, acetonitrile/aqueous co-solvent electrolyte (0.5M Zn(CF3SO3)2/AN-H2O) was used as the electrolyte of the zinc ion battery. The influence of different experimental conditions on the electrochemical properties of ZnMn2O4 was studied by orthogonal experiment. In order to improve its electrochemical performance and cycling ability, the non-equivalent substitution of pure ZnMn2O4 was performed by adding Al3+. The non-equivalent substitution of Al3+ reduced the cell volume of ZnMn2O4 and the mixed manganese valence appeared. The specific capacity of initial discharge increases from 52.9 mAh·g-1 to 109.4 mAh·g-1 at 0.05C, and the cycle stability is also greatly improved. After 100 cycles, the capacity retention rate was 82.3%. This work shows that ZnMn2O4 is a promising cathode material for zinc ion batteries, which expands the application of spinel oxide in zinc ion batteries.

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