Button-cell for hearing aid apparatus based on gas atomized powders of hydriding alloy La-Ni-Co-Al

Gas atomized powders of LaNi2.5Co2.4Al0.1 alloy were prepared and used for the construction of nickel/metal hydride battery. The powder characteristic s such as particle size distribution, morphology, oxygen content, crystal s tructure for different fractions were analyzed. The hydriding and electroch emical properties were evaluated too. All fractions have a similar particle morphology and only a slightly different X-ray determined lattice paramete rs of the alloy. The fractions with particle size less than 50 pm have a po or activity at both gaseous and electrochemical hydriding. This phenomenon may be attributed to the presence of fine fractions of the amorphous compon ent. Gas atomized powders of coarse fractions possess high corrosion resist ance and display a similar hydrogen and electrochemical capacity as are mel t alloys. (C) 1999 Published by Elsevier Science Ltd on behalf of Internati onal Association for Hydrogen Energy. All rights reserved.