Composite cathodes have been fabricated based on LiMn2O4 spinel powders, which were synthesized by combustion process and characterized by X-ray diffraction as a pure phase. The electrochemical response of the electrode was analyzed by cyclic voltammetry, chronopotentiometric curves and electrochemical impedance spectroscopy (EIS). Cyclic voltammograms showed two reversible processes, which is the typical response of LiMn2O4. The charge–discharge curves showed two plateaux with the charge density of 107mAhg−1. From the EIS data the Li+ diffusion coefficient was determined.