Sealed type lead acid battery

The sealed type lead acid battery according to the invention comprises a battery case having an upper wall provided with an inner surface and an outer surface (pierced with holes) in which an electrolytic solution and electrodes are received, an annular protrusion (25) provided on the inner surface of the upper wall (5) surrounding the holes (23), a pole (13) connected to the electrodes and disposed beneath the holes, a male thread member (19) having one end embedded in the pole and the other end protruding from the pole to extend from the interior of the battery case to the exterior of the battery case through the hole, and a female thread member (31) engaged with the male thread at the portion thereof protruding from the upper wall. In this arrangement, the female thread member is tightened so that the annular protrusion bites into the upper surface of the pole. In accordance with the sealed type lead acid battery having this arrangement, a male thread member and a female thread member made of a material different from that of the pole can be used, making it possible to tighten these members at a considerably high torque. Accordingly, the annular protrusion can bite the upper surface of the pole thoroughly, making it possible to isolate securely between the interior of the battery case and the exterior of the battery case and hence enhance the airtightness of the battery case.