With rapid industrialization, there is a tremendous increase in the utilization of electronics. Among various electronics, Zn–MnO2 primary batteries are used in small gadgets in very huge quantity. The disposal of spent electronic batteries via the landfill creates hazardous waste which led to environmental pollution. As spent batteries contain the valuable element, the resource recovery from the spent battery is one of the fascinating areas to meet material for sustainable energy demand. In this work, we have developed a new process for synthesis of Ni6MnO8 nano-particles via a facile chemical route using manganese chloride derived from the cathode part of the spent battery. The as prepared Ni6MnO8 has been used for electrochemical ethanol oxidation. The Ni6MnO8 shows robust electroactivity for ethanol oxidation with high current density (13.69 mAcm−2) at low oxidation peak potential (1.53 V), smaller Tafel slope value (61 mV/dec), and high current density ratio (Jf/Jb) 1.01. The observed surface area of the Ni6MnO8 sheet (136 m2/g) is ∼1.4 times higher than the maximum reported surface area till now (91.32 m2/g). The current studies indicate that non-noble metal-based mixed metal oxides derived from waste can be used as a promising anodic material for direct alkaline fuel cells.