摘要 |
Hydrogen storage alloy has: (1) a main composition expressed by the formula of Mm-(Ni-Al-Co-Mn); (2) a ratio of the number of atoms expressed by the formula of (Ni-Al-Co-Mn) is 5.5<(Ni+Al+Co+Mn)</= 9, and 3.5 </= Ni, when Mm is set at 1 in a ratio of the number of atoms; and (3) an internal structure having a hydrogen storage alloy phase expressed by the general formula of AB5, and a second phase existing in the hydrogen storage alloy phase. Also, another hydrogen storage alloy has: (1) a main composition expressed by the formula of Mm-(Ni-Al-Co-Mn-Mo); (2) a ratio of the number of atoms expressed by the formula of (Ni-Al-Co-Mn-Mo) is 5.5<(Ni+Al+Co+Mn+Mo)</= 8, and 3.5 </= Ni, when Mm is set at 1 in a ratio of the number of atoms. This hydrogen storage alloy is advantageous in ensuring hydrogen-storing ability, hydrogen-emitting ability, and electrical conductivity. <IMAGE> |