| 摘要 |
PROBLEM TO BE SOLVED: To make cycle life longer in an alkali storage battery of high capacity using a hydrogen storage alloy in which the main phase has a hexagonal crystal structure. SOLUTION: A hydrogen storage alloy expressed by general formula Ln<SB>1-x</SB>Mg<SB>x</SB>Ni<SB>y</SB>A<SB>z</SB>, and in which the main phase has a hexagonal or rhombohedral crystal structure on the negative electrode of the alkali storage battery, and the one in which the number of the average value of the linear subphases with a thickness of≥50 nm present in the range of 10μm×10μm in the cross section reaches≤3 is used. In the formula, Ln is at least one kind of element selected from rare earth elements including Y, and Ca, Zr and Ti; (A) denotes at least one kind of element selected from Co, Fe, Mn, V, Cr, Nb, Al, Ga, Zn, Sn, Cu, Si, P and B; and the conditions of 0.15≤x≤0.30, 0<z≤1.5 and 2.8≤y+z≤4.0 are satisfied. COPYRIGHT: (C)2011,JPO&INPIT |
