Preparation and electrochemical properties of some (Sc1-xTix)Ni alloys

A series of (Sc1-xTix)Ni alloys and their hydrides (Sc1-xTix)NiHy, where x= 0, 0.1, 0.3, 0.5, and y=2.9, 2.58, 2.23 and 1.55, have been prepared. The a bility to store hydrogen gradually decreases with increasing Ti content in line with the reduction of the unit cell volume from 32.16 Angstrom(3) for ScNi to 29.68 Angstrom(3) for (Sc0.5Ti0.5)Ni. The electrochemical discharge capacity, however, varies in a more complex manner with (Sc0.7Ti0.3)Ni com position displaying the highest value of 231 mAh/g. The discharge capacity losses after 10 electrochemical charge-discharge cycles also vary non-linea rity between 46% for (Sc0.9Ti0.1)Ni and 5% for (Sc0.5Ti0.5)Ni. (C) 2000 Els evier Science S.A. All rights reserved.