Abstract Gas atomized powders of LaNi 2,5Co 2,4Al 0,1 alloywere prepared and used for the construction of nickel/metal hydride battery. The powdercharacteristics such as particle size distribution, morphology, oxygen content, crystal structure fordifferent fractions were analyzed. The hydriding and electrochemical properties were evaluatedtoo. All fractions have a similar particle morphology and only a slightly different X-ray determinedlattice parameters of the alloy. The fractions with particle size less than 50 μm have apoor activity at both gaseous and electrochemical hydriding. This phenomenon may be attributedto the presence of fine fractions of the amorphous component. Gas atomized powders of coarsefractions possess high corrosion resistance and display a similar hydrogen and electrochemicalcapacity as arc melt alloys. © 1999 Published by Elsevier Science Ltd on behalf of InternationalAssociation for Hydrogen Energy. All rights reserved.