Patent ID: 7300720
Filing Date: 2007-11-27
Classification: C01B,C22C,C23C,H01M,Y02E,Y02P,Y10S

Abstract:
1. A hydrogen absorbing alloy containing not higher than 10% by volume including 0% by volume of a phase having an AB 2 type crystal structure, said hydrogen absorbing alloy having a composition represented by general formula (4) given below, wherein a parallel growth region precipitates in at least one crystal grain of a principal phase, and the parallel growth region has a crystal structure differing from a crystal structure of the principal phase: where R is at least one element selected from rare earth elements, said rare earth elements including Y and a Ce content of said R being lower than 20% by weight including 0% by weight, M4 is at least one element selected from the group consisting of Mn, Fe, Al, Ga, Zn, Sn, Cu, Si, B, Nb, W, Ti, Zr, In, Mo, V, Cr, P and S, the atomic ratios of a, X, Y, Z and α are respectively satisfy conditions of: 0.15≦a≦0.33, 0.06≦X≦0.15, 0≦Y≦0.2, 3.15<Z≦3.55 and 0≦α<0.135.