| 摘要 |
PURPOSE:To improve the cycle life by specifying the diameter of the plural holes furnished on a negative electrode plate. CONSTITUTION:Plural holes 2a are furnished on a negative electrode plate 2, and the diameter R of the holes 2a is made larger than the thickness (d) of the negative electrode plate and smaller than two times the thickness (d), d<R<2d. As a result, the oxygen gas generated from a positive electrode plate 1 can be scattered rapidly from the holes 2a. Moreover, the oxygen cycle reaction is made rapidly, the generation of hydrogen in the negative electrode 2 is suppressed, and the scattering of the moisture in the electrolyte to the outside can be controlled. In such a composition, the deterioration of the cycle life resulting from a decrease of the electrolyte amount can be prevented. |
