Effects of Co, Mn contents on the electrochemical characteristics of the LaNi3.8(Co + Mn)0.96Al0.24 electrodes in potassium hydroxide electrolyte

The effects of Co and Mn contents on the electrochemical characteristics of the LaNi3.8(Co+Mn)0.96Al0.24 electrodes were examined systematically. The lattice cell parameters, discharge characteristics, high-rate charging or discharging performance and cyclic stability of the series of alloys were all evaluated. The experimental results show that Co would play the role of improving the electrochemical capacity and discharge cell voltage. In addition, the cyclic stability of the metal hydride electrodes could be enhanced with increasing the Co content in the alloys. On the other hand, replacing the Co by Mn in the alloys could cause a expansion of the lattice cell volume and assist hydrogen diffusion in the metal hydride electrodes, which subsequently promoted the high-rate charging performance.