| 摘要 |
PURPOSE:To prevent an increase in resistance between electrodes, to prevent a decrease in capacity in high rate discharge, and to increase the cycle life of a battery by using a plurality of microporous films having defferent pore sizes and by arranging the microporous film having the smallest pore size on the nearest side to a zinc negative electrode of the multilayer separator. CONSTITUTION:A multilayer separator comprising a plurality of microporous films having different pore sizes is arranged between electrodes. The microporous film having the smallest pore size is arranged on the nearest side to a zinc negative electrode of the separator to prevent the piercing of dendric zinc crystals through the separator. Since this microporous film can sufficiently retard the growth of dendritic zinc crystals, other microporous films are requested only to perform auxiliary function for this purpose and their pore sizes can sufficiently be increased. Even though the multilayer separator comprising a plurality of microporous films is used, the resistance between electrodes of a storage battery is not increased so much and decrease in capacity in high rate discharge is prevented. |
