| 摘要 |
PROBLEM TO BE SOLVED: To restrain oxygen overvoltage from being dropped under the high temperature by taking a nickel electrode formed by carrying electrode mixture containing a specified compound on a collector as a positive electrode. SOLUTION: A nickel electrode has a three-dimensional network structure in which a collector is provided with a communication hole, an electrode mix supported on it takes Ni(OH)2 as a main component and contains a Co compound, a Dy compound and/or a Ho compound as essential components. The Dy compound and the Ho compound are dissolved as a complex ion by being reacted with OH<-> in electrolyte in the first charging, dispersed between primary particles of Ni(OH)2 , and cover the surface of Ni(OH)2 powder. Therefore, the state of the surface of Ni(OH)2 is changed, and the oxygen overvoltage of Ni(OH)2 or NiOOH is shifted to the higher side. As a result, the oxygen overvoltage of the nickel electrode under the high temperature is raised, and the charging efficiency of the battery is improved. |
