| 摘要 |
<p>A hydrogen storage alloy which has a composition represented by the formula (1): RNiaCobAlcMndMe ---- (1) wherein R represents a rare earth element including Y, or the like, M represents Mg, Fe or the like, and 3.50 ≤ a ≤ 4.95, 0.10 ≤ b ≤ 0.50, 0.35 ≤ c ≤ 0.55, 0.10 ≤ d ≤ 0.45 and 0 ≤ e ≤ 0.10, provided that 5.10 ≤ a+b+c+d+e ≤ 5.50, and has a particle diameter of 10 μm or less and, at a grain boundary and within a grain of the base phase constituting the alloy, a second phase having a Al content and a Mn content greater than those of the base phase. The hydrogen storage alloy is useful as an electrode material for a secondary cell has achieved the reduction of a cobalt content, and also offers a good balance of a level of activities such as initial activity and discharge characteristics, corrosion resistance, and life characteristics, and further is excellent in recyclability.</p> |
