Preparation of Hydrogen Electrode of Nickel-Hydrogen battery by Eletrodeposition

摘要

A novel electrodeposition technique for preparing the catalyst layer of hydrogen electrode of nickel- hydrogen battery was investigated, which was expected to reduce the noble metal catalyst loading. This method involved the electrodeposition of platinum, palladium, or palladium-platinum alloy into a preformed amorphous carbon substrate comprising the Vulcan XC-72R carbon black and a photo-etched nickel mesh. The electrodep0sited catalysts were characterized by diffraction (XRD) and transmission electron microscope (TEM). Experimental results showed that carbon supported Pt particles with the size about 5 nanometers and good uniformity could be prepared with pulse current electrodeposition by optimizing pulse parameters. Galvanometric polarization, cyclic voltammetry, electrochemistry impedance spectrum and chronoamperometry curve characterization showed that the electrodeposited Pd electrode exhibited poor catalyst activity and a electrochemistry reaction controlled step. The catalyst activity was improved gradually by adding minim amount of Pt and performed better than the electrodeposited Pt electrode. Compared with that of traditional hydrogen electrode with pure platinum black as catalyst, the catalyst loading of the hydrogen electrode prepared from electrodeposition was reduced by more than 60 percent. The nickel-hydrogen battery using the hydrogen electrode prepared from electrodeposition as anode was tested. The test results showed that the battery performed well at high discharge rate with high discharge plateau.