In this work are present the results obtained from the electrochemical characterization of a metal hydride type MmNi5-XMX impregnated with palladium, palladiumnickel and nickel nanoparticles as catalytic precursors for hydrogen absorption. The hydrogen absorption was investigated in the charge/discharge mechanism of a metal hydride via electrochemical process. The complete study involved the analysis of linear and anodic polarization, charge/discharge cycles, the application of an electrochemical model and electrochemical impedance spectroscopy to investigate the amount of hydrogen absorbed as a function of the catalytic precursors. The use of Pd nanoparticles showed the best results as catalytic precursor to absorb more hydrogen than other precursor systems. Copyright (C) 2011 John Wiley & Sons, Ltd.