<p>This research introduces an innovative cathode material for nickel-zinc rechargeable batteries, developed from diverse mixed metal oxide (MMO)/MnO₂ compositions. The material is synthesized through the calcination of NiCoFe-layered double hydroxide (LDH)/MnO₂ heterostructure at varying temperatures. The findings showed that the sample fabricated at 500&#xa0;°C exhibited the best electrochemical properties, remarkable electrochemical capacity (236.11 mAhg^− 1 at 10 Ag^− 1), and good cycle life (86% capacity retention after 500 cycles at 10 Ag^− 1). The observed enhancements can be attributed to the specific compositions of trimetallic mixed oxides (NiO, CoO, FeO) in conjunction with MnO₂, characterized by an amorphous phase, favorable morphology, and enhanced structural stability. These factors contribute to the improved diffusion of guest ions (OH⁻) within a structured and more reactive surface area, thereby facilitating electrochemical reactions. Moreover, a homemade battery (pouch cell) was prepared and demonstrated better rate performance (84.44 mAhg^− 1 at 8 Ag^− 1) and capacity retention of 90.17%, with a coulombic efficiency of about 95.32%. The newly developed MMO composite is anticipated to serve as a promising and effective cathode electrode in Ni-Zn rechargeable batteries for various applications, aiming to provide reliable and safe energy storage for clean technologies.</p> Graphical abstract <p></p>