Storage battery with closure seal and vent means

Claim 1

In a battery having a casing and an electrode-dielectric assembly within said casing, said casing comprising a cylindrical side wall closed at one end and open at the other end, an annular resilient sealing member, said side wall being closed at one end thereof and formed at point adjacent the open end thereof with an annular inwardly directed radial portion for seating said sealing member, said sealing member comprising an annular body portion and an annular lip portion upstanding from said body portion and an annular groove disposed inwardly of said lip portion, a closure member having a downwardly extending peripheral portion received in the groove of said sealing member, the upper annular marginal portion of said casing wall being crimped radially inward to compress the lip and body portions of said sealing member against the seating portion of said side wall and to seal the peripheral portion of the closure member between the lip and body portions of said sealing member, said closure member being formed with a gas vent for passing gas from the interior of said casing outwardly thereof, a resilient valve member overlying the vent in said closure member, and a cap member mounted on the outer surface of said closure member to retain said valve member in place, said cap member being formed with a gas vent for establishing communication with the first mentioned gas vent when said valve member is displaced from said first mentioned gas vent in response to pressures internally of said casing which are in excess of a predetermined gas pressure.