Polarization studies with Ovonic metal hydride batteries. I

The polarization characteristics of metal hydride negative electrodes and cells constructed using these electrodes were studied. The polarization curve is linear (ohmic) at the lower current range, and it approaches a limiting current at higher current densities. The polarization resistance depends on the state of charge and is time dependent. The effects of material composition and design parameters such as electrolyte level, electrode density, and particle size on the polarization resistance was also investigated. The polarization characteristics were studied at different temperatures, and conclusions with regard to the origin of the polarization are drawn. AC impedance measurements were performed at the electrode-solution. The results of all the above measurements are presented and discussed