The electrochemical properties of a multiwalled carbon nanotube (MWNT)-Ni electrode were investigated. A high discharge capacity of 200 mAh g(-1) of MWNTs is obtained. The MWNTs-Ni electrode was found to have high rate capability and long charge-discharge cycle life. The electrochemical mechanism of hydrogen adsorption and hydrogen oxidation (electrochemical hydrogen desorption) of the MWNTs-Ni electrode at the Ni site was studied using cyclic voltammetry. Electrochemical impedance spectra showed that the MWNTs-Ni electrode has high electrochemical activity due to its large reaction area.