ELECTRICAL-PROPERTIES OF NICKEL-HYDROXIDE FOR ALKALINE CELL SYSTEMS

The electrical behaviour of nickel hydroxide/oxyhydroxide electrodes f or advanced alkaline cell systems is investigated as a function of oxi dation degree which usually changes during practical operation of thes e systems, The d.c. electrical conductivity, relative dielectric const ant and loss factor as a function of oxidation degree, temperature and frequency (a.c. properties) are investigated and discussed. Moreover, the effect of water absorption on the electrical conductivity is inve stigated. An insulating behaviour and ionic mechanism of conduction is pointed out for the uncycled and reduced electrodes, while the oxidiz ed electrode behaves essentially as a semiconductor. Water absorption causes a strong increase in the electrical conductivity of the uncycle d and reduced electrodes. Cycling enhances the dielectric losses of th e active material.