Electrochemical Reduction of Nickel(II) Hydroxide Deposited on Carbon Powder and Application to a New Activation Method for Hydrogen Storage Alloy Negative Electrodes

Abstract

After cathodic polarization, nickel(II) hydroxide-deposited carbon powder [Ni(OH)₂/C] was investigated by XRD, magnetism measurement, and TEM observation. More than 1.4% of the nickel(II) hydroxide deposited on the surface of the carbon powder was electrochemically reduced and fine nickel particles were formed. Since the fine nickel particles act as active sites for charge/discharge reactions, the initial activation of hydrogen storage alloy negative electrodes was promoted by adding Ni(OH)₂/C.