| 摘要 |
PURPOSE:To lengthen life while maintaining its discharge performance by preventing the falling of active substance by using a structure in which the glass mat is made up of a dense layer and a rought layer and the dense layer is made to touch with the positive plate and also plate groups are pressed by a specific force. CONSTITUTION:A glass mat is made up of the two layers, the dense layer 2 of 1-micron diameter small glass fibers and the rough layer 3 of approx. 19-micron diameter large glass fibers, in which the dense layer 2 is touched with the positive plate 1 and the rough layer 3 is faced the negative plate 5 through the separator 4. The element having such a structure is strongly pressed by a pressing force, or the pressing force of the glass mats 2 and 3 to the surface of the positive plate 1 of 20-80kg/dm<2> per unit area of plates at both ends of the element in the dry state before injecting liquid. |
