Effect of Additives in the Stabilization of the α Phase of Ni(OH)[sub 2] Electrodes

Abstract

The present work deals with the voltammetric and electrogravimetric behavior of Ni(OH)2Ni(OH)2 electrodes in alkaline solutions and the effect of some additives, such as Co2+,Co2+, Cd2+,Cd2+, and Zn2+,Zn2+, in the active material. The electrochemical behavior of the α or β phases with the incorporation of the additives is analyzed by use of the electrochemical quartz crystal microbalance. Only Zn2+Zn2+ as additive leads to the complete stabilization of the α phase avoiding, since the first cycle, the insertion of alkaline cations from the electrolyte. In all other α phases, the electroneutralization of charge is achieved by a small but representative participation of cations. In the case of β electrodes, protons are the responsible for charge compensation, the cations movement being negligible. © 2001 The Electrochemical Society. All rights reserved.