| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a nickel hydrogen secondary battery having high volume energy density and high cycle characteristics. <P>SOLUTION: The nickel hydrogen secondary battery is constituted by housing an alkaline electrolyte, and an electrode group 22 comprising a positive plate 24, a negative plate 26, and a separator 28 interposed between the positive plate 24 and the negative plate 26, they are spirally wound together, in a cylindrical outer can 10, and has a volume energy density of 340-450 Wh/l. Active material particles distributed on the positive plate 24 contains globular first particles 64 and non-globular second particles 66 both comprising nickel hydroxide, and in the first particles 64, a core 68 comprising nickel hydroxide is covered with a coating layer 70 made of a cobalt compound and heat-treated with alkali. When the whole mass of the first particles 64 is represented by X and the whole mass of the second particles 66 is represented by Y, a mass ratio Y/X is present in a range of 0.04-0.12. <P>COPYRIGHT: (C)2006,JPO&NCIPI |
