Rayovac Corporation

Robert Adey

John Edward Oltman

Robert B Dopp

John David Burns

Cathode cans for use in air depolarized cells, and cells made with such cans. The side wall is stronger than the bottom wall, and has a smoother outwardly-disposed surface than the respective bottom wall surface. Strength, and thus hardness, of the side wall relates to strength, and thus hardness, of the bottom wall, as hardness of 130-185 relates, to hardness of 93-117, on the Vickers scale. Preferred hardness of the side wall is about 130 to 185; and of the bottom wall is about 93 to 117. The side wall is drawn, and an outwardly-disposed surface of the side wall is ironed. As ironed, the surface finish is related to surface finish of the bottom wall, at the same stage, as surface finish R of less than 2, preferably about 0.5 to about 1.5, microinches, is related to surface finish R of about 2 to about 5, preferably about 2.5 to about 4.5, microinches. Thickness of the side wall is generally up to about 85 percent as great as thickness of the bottom wall. In methods of forming cathode cans in a metal strip, a die has an initializing land, an inner side wall, a cavity inwardly of the inner side wall, and a lip between the initializing land and the inner side wall.

Air depolarized electrochemical button cell

This invention pertains to metal-air electrochemical cells wherein one or more air entry ports is located in the bottom of the cathode can, to provide for entry of oxygen-rich air into the cathode can, where the oxygen participates in the electrochemical reaction whereby the cell produces electrical energy. In this invention, extremely small air ports are provided, along with methods of reliably fabricating such small air ports, where a tool impression extends around the port. Generally, the use of an increased number of small air ports distributed over the bottom of the cathode can, opposite the reaction surface of the cathode assembly, wherein the overall open area of the ports is not increased, results in less moisture traversing the air ports, into or out of the cell. Accordingly, moisture loss, or gain, as a function of electrical energy produced, is thereby reduced.

Metal-air cathode can, and electrochemical cell made therewith

Cathode cans for use in air depolarized cells, and cells made with such cans. The side wall is stronger than the bottom wall, and has a smoother outwardly-disposed surface than the respective bottom wall surface. Strength, and thus hardness, of the side wall relates to strength, and thus hardness, of the bottom wall, as hardness of 130-185 relates to hardness of 93-117, on the Vickers scale. Preferred hardness of the side wall is about 130 to 185; and of the bottom wall is about 93 to 117. The side wall is drawn, and an outwardly-disposed surface of the side wall is ironed. As ironed, the surface finish is related to surface finish of the bottom wall, at the same stage, as surface finish R,of less than 2, preferably about 0.5 to about 1.5, microinches, is related to surface finish R,of about 2 to about 5, preferably about 2.5 to about 4.5, microinches. Thickness of the side wall is generally up to about 85 percent as great as thickness of the bottom wall. In methods of forming cathode cans in a metal strip, a die has an initializing land, an inner side wall, a cavity inwardly of the inner side wall, and a lip between the initializing land and the inner side wall. Ratio of outer radius of the lip to inner radius of the lip is about 2/1 to about 8/1. Ratio of clearance between punch and die to thickness of the metal strip is about 0.5/1 to about 0.85/1, whereby moving the punch and metal strip into the cavity draws the metal, and irons the outer surface of the metal.

Method for making a cathode can from metal strip

This invention pertains to metal-air electrochemical cells wherein one or more air entry ports is located in the bottom of the cathode can, to provide for entry of oxygen-rich air into the cathode can, where the oxygen participates in the electrochemical reaction whereby the cell produces electrical energy. In this invention, extremely small air ports are provided, along with methods of reliably fabricating such small air ports Generally, the use of an increased number of small air ports distributed over the bottom of the cathode can, opposite the reaction surface of the cathode assembly, wherein the overall open area of the ports is not increased, results in less moisture traversing the air ports, into or out of the cell. Accordingly, moisture loss, or gain, as a function of electrical energy produced, is thereby reduced.

Growing community of inventors

South Shields, United Kingdom

Robert Adey