Metal-air depolarized cell having restricted gas passageway

摘要

A gas-depolarizable galvanic cell is provided having restricted gas access to the cathode. The cell is generally a metal-air cell, and may particularly be a button cell suitable for use in electronic watches, hearing aids and the like. The restricted gas access to the cathode comes either by way of a very small aperture in the cell container, or in an additional barrier layer placed within the cell. The cross-sectional area of the gas passageway is less than the projected area of the gas passageway through the thickness of the container or additional barrier layer; and may be formed by piercing or punching but more particularly by exposing the container or the material of the additional barrier layer to a laser beam.