HYDROGEN STORAGE NI-ZR SERIES ALLOY AND CLOSED-TYPE NI-HYDROGEN STORAGE BATTERY

摘要

PURPOSE:To obtain the hydrogen storage Ni-Zr series alloy having high hydrogen occluding and discharging capacity and low dissociation pressure of equilibrium hydrogen in the region of room temp. and having excellent alkali resistance at a low cost by specifying the compsn. constituted of Ti, Zr, Mn, W, Fe and Ni. CONSTITUTION:The hydrogen storage Ni-Zr series alloy has the compsn. contg., by weight, 5 to 20% Ti, 10 to 37% Zr, 5 to 30% Mn, 0.01 to 15% W and 1 to 30% Fe, furthermore contg., at need, one or both of 0.05 to 6% Cr and 0.01 to 5% Al and the balance Ni with inevitable impurities and has an MgZn2-type crystal structure, which shows excellent corrosion resistance and durability in an alkaline electrolytic soln., has high hydrogen occluding and discharging capacity and low dissociation pressure of equilibrium hydrogen in the region of room temp., has high hydrogen oxidizing capacity, is hard to pulverize, causes no pollution and is low-cost. Thus, by using the alloy as the active material in the negative electrode, the closed type Ni hydrogen storage battery having high discharging capacity and showing preferable capacity such as prolonged charging discharging cycle life, excellent rapid charging- discharging properties and low self-discharging can be obtd.