Morphological considerations of the nickel chloride electrodes for zebra batteries

Electrochemical and morphological investigations of various nickel chloride electrodes were carried out. Three different types of Nickel chloride electrodes were investigated in this study: a nonporous nickel substrate, a nickel felt, and a porous sintered electrode. It was observed that the nickel chloride layer formation during the charge limits the area capacity of solid nickel to 0.6 C/cm2. There is also a direct relationship between the electrochemical performance and morphological parameters of the nickel chloride electrode. The capacity trend of these electrodes was explained by considering both the surface area and the pore-size distribution necessary for an effective mass transport during charge and discharge reactions. A rational approach to fabricate electrodes with improved nickel utilization is also discussed.