Microstructure and Electrochemical Properties of a LaMgAlMnCoNi Based Alloy for Ni/MH Batteries

The microstructure and electrochemical properties of a La0.7Mg0.3Al0.3Mn0.4Co0.5Ni3.8 hydrogen storage alloy have been studied. The anode was prepared using a mixture of the ingot alloy in the as-cast state with carbon black and polytetrafluoroethylene (PTFE) as a binder. A Ni (OH)2 electrode was used as the cathode of the square-type test cell. A separator was used together with a 6M KOH electrolyte. Microstructure and phase composition of the alloy have been investigated using inductively coupled plasma atomic emission spectrometry (ICP-AES), scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDX) and X-ray diffraction analysis (XRD). A niobium-containing alloy has also been included for a comparison.