Hitherto a variety of hydrogen occluding alloys have been suggested, as exemplified by the hydrogen occluding alloy disclosed recently in "International Symposium About Foundation And Application Of Metal-Hydrogen System", held on Nov. 6 to 11, 1994, in Fujiyoshida, Japan, in which there are disclosed alloy samples prepared from compositions according to the formula: Ti.sub.0.5-x/2 Zr.sub.0.5-x/2 La.sub.x Mn.sub.0.8 Cr.sub.0.8 Ni.sub.0.4, in which x=0.0.about.0.1.
A fact has been known that the foregoing hydrogen occluding alloy has a hydrogen absorbing (i.e., hydrogen occluding) function with which an ingot La--Ni type alloy phase dissociates hydrogen-bearing molecules (e.g., H.sub.2, H.sub.2 O) or ions (e.g., H.sub.3 O.sup.+) in the atmosphere to provide hydrogen atoms (H) due to the catalyzing function thereof and absorbs dissociated hydrogen atoms at a speed significantly higher than the speed at which the main phase absorbs hydrogen atoms, and therefore the absorption of hydrogen atoms is mainly carried out through the La--Ni type alloy. On the other hand, the hydrogen discharge is performed by a function contrary to the foregoing function, i.e., by reversing the absorption.
In a case where the hydrogen occluding alloy is adapted to, for example, the electrode for a battery, a fact has been known that the electrode including the hydrogen occluding alloy is subjected to initial activation by repeating charging and discharging until the electrode has a sufficiently large discharge capacity (that is, until the discharge capacity, attainable due to the hydrogen occluding alloy, becomes maximum). The battery is put to practical use after the initial activation has been performed.