| 摘要 |
PURPOSE:To effectively keep the airtightness of a battery to prevent deterioration in capacity by installing projections for partially pressing a rubber plate in a press-down plate, and firmly fixing the rubber plate which covers the opening of a vent in the periphery of the vent. CONSTITUTION:A step 1a which is wider than the diameter of a vent 1 in the upper part of the vent 1, and a rubber plate 2, which is resistant to sulfuric acid and capable of long term use, such as chloroprene is arranged so as to cover the vent 1. A plurality of projections 3a which extend downward and have curved edges are annularly installed at suitable intervals in a press-down plate arranged on the rubber plate 2. The rubber plate 2 is pressed by the projections 3a so that the edges of the projections are slightly embedded in the plate 2 to fix the periphery of the vent 1. By firmly fixing the rubber plate 2, the airtightness of a battery is effectively kept and capacity deterioration of the battery can be prevented. |
