| 摘要 |
PROBLEM TO BE SOLVED: To prevent liquid leakage during storage and fast power charge by housing and sealing a positive electrode, a negative electrode, and a separator in a bottomed cylindrical container and making an actual volume of the positive and negative electrodes and the separator excluding a cavity part to this sealed container after sealing a specific ratio. SOLUTION: In a bottomed cylindrical container 1, an electrode group 5 fabricated by laminating a positive electrode 2, a separator 3a, and a negative electrode 4 each other, and winding them in spiral shape is housed. The negative electrode 4 is disposed in the outer-most periphery of the electrode group 5, and is brought into electrical contact with the container 1, and an alkali electrolyte is housed in the container 1. A first circular sealing plate 7 having a hole 6 at its center is disposed at the top opening of the container 1, and the sealing plate 7 is fixed with air tightness in the container 1 via a ring-shaped insulation gasket 8 by means of caulking process in which this top opening diametrically is contracted is inwardly. With this arrangement, the actual volume of the positive and negative electrodes 2 and 4 and the separator 3a excluding the cavity part is 50 to 70% to the volume of the container 1, more preferably, 55 to 65%. |
