Hydrogen absorbing alloy powder and method for producing hydrogen absorbing alloy powder

Abstract

The present invention relates to a surface treatment for hydrogen-absorbing alloy. More particularly, the present invention relates to a surface treatment for hydrogen-absorbing alloy by which the poisoning resistance of a surface of alloy powder with respect to oxide film, water or absorbing gas can be enhanced so that activation treatment can be easily conducted on alloy powder. In the method, the poisoning resistance is enhanced by forming a protective film, which contains at least one of sulfide and fluoride, on the surface of hydrogen-absorbing alloy powder in an atmosphere containing SF6 gas when hydrogen-absorbing alloy is crushed or hydrogen-absorbing alloy is in a state of powder or when hydrogen-absorbing alloy is made into powder by rapidly cooling and solidifying. Further, the above method includes: a process in which hydrogen-absorbing alloy is accommodated in a container and crushing of hydrogenation is conducted on the alloy in an atmosphere of hydrogen; a process of dehydrogenation in which gases are withdrawn from the container; and a process in which heat treatment is conducted in the container, wherein the atmosphere in the container contains SF6 gas.

Dependencies are inferred from the claim text.