In this work, we report the synthesis and utilization of carbon nitride enriched leady oxide (CNLO) as negative active mass (NAM) which enhances the charge–discharge characteristics of the lead-acid cells. The CNLO NAM were characterized by X-ray diffraction (XRD), Raman spectroscopy, Field emission scanning electron microscopy (FE-SEM), cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS), respectively. Cells constructed with CNLO NAM exhibit remarkable improvement in the rate capability, active material utilization, cycle performance and charge acceptance compared to that of the cells constructed with conventional NAM.