Metal-supported seals for galvanic cells

In combination, a cylindrical sealed galvanic cell, having an anode, a cathode, and a generally cylindrical can into which the principal components of the cell are placed, said can having a closed end and an open end;

• and further comprising a sealing and insulating member at the open end of said can, said member being held in sealing relationship to said can by a crimp formed at the top edge of said can;
• where:
• said sealing and insulating member comprises a molded thermoplastic body portion and a metal disc portion over said thermoplastic body portion, with a space between said disc and said thermoplastic body;
• and
• said metal disc has a central opening therein formed with a plurality of spaced radially inwardly directed projections fitted with the central opening of said projections in interference fit over a centrally located upwardly extending boss in the upper surface of said thermoplastic body portion;
• wherein the openings between said projections provide a passage for pressure equalization between the outside of said cell and the space between said disc and said molded thermoplastic body.

In combination, a cylindrical sealed galvanic cell, having an anode, a cathode, and a generally cylindrical can into which the principal components of the cell are placed, said can having a closed end and an open end;

• and further comprising a sealing and insulating member at the open end of said can, said member being held in sealing relationship to said can by a crimp formed at the top edge of said can;
• where:
• said sealing and insulating member comprises a molded thermoplastic body portion and a metal disc portion over said thermoplastic body portion, with a space between said disc and said thermoplastic body;
• and said metal disc has a central opening therein formed with a plurality of spaced radially inwardly directed projections fitted with the central opening of said projections in interference fit over a centrally located upwardly extending boss in the upper surface of said thermoplastic body portion;
• wherein the openings between said projections provide a passage for pressure equalization between the outside of said cell and the space between said disc and said molded thermoplastic body;
• where the central area of said disc is higher than the periphery thereof;
• where there is an upwardly extending skirt around the outer edge of said upper surface of said molded thermoplastic body;
• where at least one portion of said molded thermoplastic body, other than at its center or outer periphery, is formed with a thickness less than that of the surrounding material thereof so as to provide a rupturable vent area of said molded thermoplastic body in the event that pressure within said sealed galvanic cell reaches a predetermined level;
• and where the lower surface of said disc is supported above the upper surface of said molded thermoplastic body by at least one ledge formed in said upper surface and spaced away from said central boss and away from said upwardly extending skirt.

In combination, a cylindrical sealed galvanic cell, having an anode, a cathode, and a generally cylindrical can into which the principal components of the cell are placed, said can having a closed end and an open end;

• and further comprising a sealing and insulating member at the open end of said can, said member being held in sealing relationship to said can by a crimp formed at the top edge of said can;
• where:
• said sealing and insulating member comprises a molded thermoplastic body portion and a metal disc portion over said thermoplastic body portion, with a space between said disc and said thermoplastic body;
• and
• said thermoplastic body portion has an inwardly directed shoulder at its periphery subtended by a downwardly and outwardly extending discontinuous skirt portion, which is formed as a plurality of discrete leg-like projections;
• and
• said metal disc has a central opening therein formed with a plurality of spaced radially inwardly directed projections fitted with the central opening of said projections in interference fit over a centrally located upwardly extending boss in the upper surface of said thermoplastic body portion;
• wherein the openings between said projections provide a passage for pressure equalization between the outside of said cell and the space between said disc and said molded thermoplastic body.