LEAD STORAGE BATTERY

A lead storage battery including a cell, a cell chamber, and a gas exhaust unit. The gas exhaust unit includes a small chamber provided in a battery lid and including a first exhaust path having an opening at the cell chamber side, a covering body mounted on a bottom wall of the small chamber to cover the opening of the first exhaust path, a drop-off prevention member provided in an upper part of the small chamber and including a second exhaust path, a gap formed in at least a part between the bottom wall of a periphery of the opening and the covering body, and space for allowing movement of the covering body between the covering body and the drop-off prevention member in the small chamber. The gas is exhausted to an outside via the first exhaust path, the gap and the second exhaust path.