HYDROGEN STORAGE ALLOY, AND ELECTRODE FOR NICKEL-HYDROGEN BATTERY

摘要

A hydrogen-absorbing alloy, which is used as a negative electrode material of nickel-metal hydride secondary batteries for hybrid electric vehicles, and particularly for batteries to drive electric motors of hybrid electric vehicles, is an AB 5 -type alloy having a CaCu 5 -type crystal structure and the general formula R Ni a Co b Al c Mn d (R: mixture of rare earth metals), wherein 4.15‰¦a‰¦ 4.4, 0.15‰¦b‰¦0.35, 1‰¦c/d‰¦1.7, 5.25‰¦a + b + c + d‰¦5.45.