Ab5 type-based hydrogen storage alloys, methods of preparation and uses thereof

A hydrogen storage alloy having an AB5 type crystal structure, its A site contains La, Ce and MI elements, and its B site contains Ni, Co and Fe elements, represented by the general Formula (I):

• LaxCeyMI(1-x-y)NiaCobFecMd (I)
• in which x, y, a, b, c and d are molar ratios, where M1 is at least one element selected from Y, Ti, and Zr and M is selected from Cu and Mn;
• 0.15 ≤x≤0.95;0.05≤y≤0.85;
• 0≤(1-x-y)≤0.1;
• 3.8≤a≤4.2;
• 0.1≤b≤1.2;
• 0.01≤c≤0.3;
• 0≤d≤0.1;
• 4.8≤(a+b+c+d) ≤5.15.

A method for the preparation of hydrogen storage alloy having an AB5 type crystal structure rapid melt solidification by spinning roller quenching, wherein said method comprises the steps of:

• providing a melt of all the metal elements in a furnace under a controlled inert atmosphere at a pressure from about 30 KPa to about 70 KPa;
• casting the melt within said furnace onto a spinning roller rolling at a speed from about 1.5 to about 9 m/s where the melt rapidly solidifies and breaks into flakes when entering a cooling unit;
• leaving the flakes to further cool down to a temperature below 50° C.;
• filling the furnace with air and collecting the obtained flakes.