Alkaline cell with gelled electrolyte and rupturable means

Claim 2

AN ELECTROCHEMICAL CELL OF THE OXYGEN DEPOLARIZATION TYPE COMPRISING A CASING, A COVER THEREFOR, A TUBULAR METALLIC MEMBER IN SAID CASING HAVING PERFORATIONS IN ITS WALL, A POSITIVE ELECTRODE ABOUT SAID MEMBER, SAID TUBULAR METALLIC MEMBER EXTENDING FOR THE FULL LENGTH OF SAID TUBULAR METALLIC MEMOUTWARDLY OF ONE END THEREOF, GELLED ALKALINE ELECTROLYTE SURROUNDING SAID POSITIVE ELECTRODE, A NEGATIVE ELECTRODE WHICH EXPANDS DURING DISCHARGE OF THE CELL AND BEING OF LESS HEIGHT THAN SAID POSITIVE ELECTRODE AND COMPRISING POWDERED ZINC IN ALKALINE GEL SURROUNDING SAID GELLED ALKALINE ELECTRLYTE, A PORTION OF SAID ELECTROLYTE OVERLYING THE UPPERMOST END OF SAID NEGATIVE ELECTRODE, MEANS FOR SEALING OFF THE LOWERMOST END OF

Claim 3

An electrochemical cell according to claim 1, wherein said gelled alkaline electrolyte comprises an alkali hydroxide solution with starch gelling agent whose concentration in said solution ranges from about 150 to 240 grams per liter.

Claim 4

An electrochemical cell according to claim 2, wherein said alkali hydroxide solution is potassium hydroxide having a normality ranging from approximately 7N to 13.5N.

Claim 5

An electrochemical cell according to claim 2 wherein said starch gelling agent is a native starch.

Claim 6

An electrochemical cell according to claim 2 wherein said gelling agent is treated starch, whose concentration in the alkali hydroxide solution ranges from about 160 to about 200 grams per liter.

Claim 7

An electrochemical cell according to claim 1, wherein the alkaline gel of said negative electrode comprises an alkali-hydroxide solution with starch gelling agent, said gelling agent having a concentration in said solution of from about 200 to about 225 grams per liter, and wherein said gelled alkaline electrolyte comprises an alkali-hydroxide solution with a starch gelling agent whose concentration in said last-named solution ranges from about 160 to about 200 grams per liter.

Claim 8

An electrochemical generator according to claim 6 wherein each said alkali-hydroxide solution has a normality ranging from about 7N to about 13.5N.

Claim 9

An electrochemical generator according to claim 1, wherein in said negative electrode, said powdered zinc in said alkaline gel thereof is present in the proportion of about 500 grams to about 28.5 grams of native starch gelling agent and about 150 cc of 13.5N potassium hydroxide solution, and wherein in said gelled electrolyte the percentage of native starch is about 150 grams per liter in about 150 cc of 13.5N potassium hydroxide solution.

Claim 10

An alkaline electrolyte cell of the air depolarization type including a positive electrode, means for providing access to said electrode of oxygen-containing gas, a negative electrode including powdered zinc in an alkaline gel, a gelled electrolyte interposed between the positive and negative electrodes, said cell having an expansion chamber to permit expansion of said negative electrode during discharge of said cell, said gelled electrolyte including a layer thereof serving to separate the negative electrode from said chamber, rupturable means above said layer and sealing means spaced from said rupturable means and defining said chamber and said gelled electrolyte comprising starches whose content is in the range of about 150 to 240 grams per liter.

Claim 11

An alkaline electrolyte cell of the air depolarization type including a positive electrode, means for providing access to said electrode of oxygen-containing gas, a negative electrode including powdered zinc in an alkaline gel, a gelled electrolyte interposed between the positive and negative electrodes, said cell having an expansion chamber to permit expansion of said negative electrode during discharge of said cell, said gelled electrolyte including a layer thereof serving to separate the negative electrode from said chamber, rupturable means above said layer and sealing means spaced from said rupturable means and defining said chamber and said gelled electrolyte comprising starches whose content is in the range of about 150 to 240 grams per liter.

Claim 12

Alkaline electrolyte cell of the oxygen-depolarization type in which a positive electrode supplied with oxygen or air is separated from a powdery zinc base negative electrode by a layer of gelled electrolyte, said cell having an expansion chamber, said gelled electrolyte comprising a layer extending over said negative electrode so as to separate the negative active material from the said chamber, the said electrolyte being gelled by starches, said starches in content being in the range of a concentration of about 150 to 240 grams per liter, rupturable means covering said layer and sealing means spaced from said rupturable means and with the latter means defining said expansion chamber.

Claim 13

Alkaline electrolyte cell of the oxygen-depolarization type in which a positive electrode supplied with oxygen or air is separated from a powdery zinc base negative electrode by a layer of gelled electrolyte, said cell having an expansion chamber, said gelled electrolyte comprising a layer extending over said negative electrode so as to separate the negative active material from the said chamber, the said electrolyte being gelled by starches, said starches in content being in the range of a concentration of about 150 to 240 grams per liter, rupturable means covering said layer and sealing means spaced from said rupturable means and with the latter means defining said expansion chamber.

Claim 14

Cell according to claim 10, characterized by the fact that the negative electrode comprises a zinc powder and an alkaline gel.

Claim 15

Cell according to claim 11, characterized by the fact that the alkaline gel containing the zinc powder is gelled by starches, the concentration in starches therein being between 180 and 270 grams per liter.

Claim 16

Cell according to claim 10 characterized by the fact that said starches are of a reticulated or modified structure.

Claim 17

Cell according to claim 10, characterized by the fact that said electrolyte is constituted by a solution of potassium hydroxide having a normality below 11N.

Claim 18

An electrochemical cell according to claim 1, wherein said positive electrode, said gelled electrolyte and said negative electrode are concentrically disposed about said tubular member, said tubular member at one end extending outwardly of positive electrode, said positive electrode being greater in length than said gelled electrolyte and said negative electrode, said expansion space being annular and being located between said cover and said portion of said electrolyte overlying said end of said negative electrode, said sealing means defining said expansion space and comprising a washer within said casing spaced from said rupturable means overlying said portion of said gelled electrolyte, sealing material on said washer, said cover having perforations to admit oxygen-containing gas to said cell, and said tubular member also having additional perforations to admit gas entering said cell through the perforations in said cover and to direct said gas toward said first-named perforations in said tubular member for diffuse delivery of said gas to the positive electrode in substantially perpendicular direction to the vertical axis of said cell.