Patent ID: 6261517
Filing Date: 2001-07-17
Classification: H01M,Y02E,Y10S

Abstract:
A rare earth metal-nickel hydrogen storage alloy of a composition represented by the formula:RNi.sub.a Mn.sub.b Co.sub.c Al.sub.d X.sub.ewherein R stands for one or more rare earth elements including Sc and Y, not less than 95 atom % of which is one or more elements selected from the group consisting of La, Ce, Pr, and Nd; X stands for one or more elements selected from the group consisting of Fe, Cu, Zn, V, and Nb; a, b, c, d, and e satisfy the relations of 3.9.ltoreq.a<6.0, 0.45.ltoreq.b<1.5, 0.01.ltoreq.c<0.3, 0.4.ltoreq.d.ltoreq.1, 0.ltoreq.e.ltoreq.0.2, and 5.2.ltoreq.a+b+c+d+e.ltoreq.7.5,said alloy having a matrix of CaCu.sub.5 structure, and a Mn-rich secondary phase of 0.3 to 5 .mu.m finely dispersed in said matrix at surface ratio of 0.3 to 7%.