Alkaline galvanic cells

Claim 2

AN IMPROVED ALKALINE GALVANIC CELL WHICH COMPRISES, IN COMBINATION A CELL CONTAINER, AN ANODE CHAMBER AND A CELL CLOSURE FOR SAD CELL CONTAINER, VENTING MEANS INCLUDING A VENTING ORIFIC IN SAID CLOSURE DEFINING A CONDUIT FOR THE PASSAGE OF GAS FROM SAID ANODE CHAMBER, SAID VENTING ORIFICE HAVING A TOP PORTION AND A BOTTOM PORTION, A PRESSURE MOVABLE RESEALABLE VENTING VALVE MEMBER BAISED INTO SEALING POSITION ON THE TOP PORTION OF SAID ORIFIC AND GAS-PERMEABLE, LIQUIDIMPERMEABLE MEMBRANE DISPOSED ON THE BOTTOM PORTION OF SAID VENTING ORIFICE, SAID ANODE CHAMBER INCLUDING A COMPOSITE ANODE CONTAINING ZINC PATICLES, AN ALKALINE ELECTROLYTE CROSS-LINKED POLYACRYLAMIDE, WHEREIN SAID ALKALINE ELECTROLYTE IS ABSORBED IN SAID CROSS-LINKED POLYACRYLAMIDE TO FORM ELECTROLYTE NUGGETS AND WHEREIN SAID ZINC PARTICLES ARE WETTED WITH ELECTROLYTE AND ARE DISTRIBUTED THROUGHOUT SAID COMPOSITE ANODE IN A MANNER SUCH THAT SAID ZINC PARTICLE ARE IN CONTACTING RELATION WITH SAID ELECTROLYTE NUGGETS AND WITH EACH OTHER.

Claim 3

An improved alkaline galvanic cell according to claim 1 wherein said alkaline galvanic cell is an alkaline-zinc-manganese dioxide cell.

Claim 4

An improved alkaline galvanic cell according to claim 2 wherein said composite anode is characterized by a system of interconnectable voids distributed throughout said composite anode.

Claim 5

An improved alkaline galvanic cell according to claim 2 wherein said cross-linked polyacrylamide is capable of absorbing at least about 12 times its weight of electrolyte at 100*C.

Claim 6

An improved alkaline galvanic cell according to claim 2 wherein said alkaline electrolyte is aqueous potassium hydroxide.

Claim 7

An improved alkaline galvanic cell according to claim 2 wherein said alkaline electrolyte is aqueous sodium hydroxide.

Claim 8

An improved alkaline galvanic cell according to claim 2 wherein said alkaline electrolyte is a mixture of aqueous potassium hydroxide and aqueous sodium hydroxide.

Claim 9

An improved alkaline galvanic cell according to claim 2 wherein said zinc is present in said composite anode in an amount of about 30 to about 85 percent by weight; said alkaline electrolyte is present in an amount of about 10 to about 65 percent by weight and wherein said cross-linked polyacrylamide is present in an amount of about 1 to 8 percent by weight based on the total weight of the composite anode.

Claim 10

An improved alkaline galvanic cell according to claim 2 wherein said zinc particles have a particle size which will pass through a 60 mesh screen but be substantially retained on a 325 mesh screen.

Claim 11

An improved alkaline-zinc-manganese dioxide cell which comprises, in combination a cell container, an anode chamber and cell closure for said cell container, venting means including a venting orifice in said closure defining a conduit for the passage of gas from said anode chamber, said venting orifice having a top portion and a bottom portion, a pressure movable resealable venting valve member biased into sealing position on the top portion of said orifice and a gas permeable liquid impermeable membrane disposed on the bottom portion of said venting orifice, said anode chamber including a composite anode containing 30 to about 85 percent by weight zinc particles of a particle size of 60 to 325 mesh, an alkaline electrolyte in an amount of 10 to about 65 percent by weight and a cross-linked polyacrylamide, wherein said alkaline electrolyte is absorbed in said cross-linked polyacrylamide to form electrolyte nuggets and wherein said zinc particles are wetted with electrolyte and are distributed throughout said composite anode in a manner such that said zinc particles are in contacting relation with each other and with said electrolyte nuggets, said composite anode being further characterized by a system of interconnectable voids distributed throughout said composite anode.

Claim 12

An improved alkaline-zinc-manganese dioxide cell which comprises, in combination a cell container, an anode chamber and cell closure for said cell container, venting means including a venting orifice in said closure defining a conduit for the passage of gas from said anode chamber, said venting orifice having a top portion and a bottom portion, a pressure movable resealable venting valve member biased into sealing position on the top portion of said orifice and a gas permeable liquid impermeable membrane disposed on the bottom portion of said venting orifice, said anode chamber including a composite anode containing 30 to about 85 percent by weight zinc particles of a particle size of 60 to 325 mesh, an alkaline electrolyte in an amount of 10 to about 65 percent by weight and a cross-linked polyacrylamide, wherein said alkaline electrolyte is absorbed in said cross-linked polyacrylamide to form electrolyte nuggets and wherein said zinc particles are wetted with electrolyte and are distributed throughout said composite anode in a manner such that said zinc particles are in contacting relation with each other and with said electrolyte nuggets, said composite anode being further characterized by a system of interconnectable voids distributed throughout said composite anode.

Claim 13

An improved alkaline-zinc-manganese dioxide cell according to claim 10 wherein said polyacrylamide, prior to cross-linking is of the strUcture: ((-CH2-CH(CONH2)-)m (-CH2-CH(COOY)-)n )Z where Y is hydrogen, ammonium or an alkali metal; m is a positive number from 1 to 100; n is 0, or a positive number up to 99 which may be regarded as an index of the degree of hydrolysis of m + n amide groups originally present; m plus n is equal to 100; and Z is a number from about 0.1 to 30, where Z times 100 is equal to the number of mer units between cross-links.

Claim 14

An improved alkaline-zinc-manganese dioxide cell according to claim 11 wherein said polyacrylamide cross-linked with a non-conjugated divinyl compound.

Claim 15

An improved alkaline-zinc-manganese dioxide cell according to claim 11 wherein said polyacrylamide is cross-linked with methylene bis acrylamide.

Claim 16

An improved alkaline-zinc-manganese dioxide cell according to claim 10 wherein said cross-linked polyacrylamide is formed by the copolymerization reaction of a ratio of 13 to 22 moles of acrylamide monomer per mole of methylene bis acrylamide.

Claim 17

An improved alkaline galvanic cell according to claim 2 wherein said pressure movable resealable venting valve member is a disc having a material hardness of 30 to 80 durometer.

Claim 18

An improved alkaline galvanic cell according to claim 2 wherein said pressure movable resealable venting valve member is a resilient deformable ball of an elastomeric material having a hardness of about 60 to 70 durometer.

Claim 19

An improved alkaline galvanic cell according to claim 2 wherein said gas permeable liquid impermeable membrane has a hydrogen gas permeability flow rate of at least 20,000 cc per hour per square inch at 30 psi differential pressure at 20*C.

Claim 20

An improved alkaline galvanic cell according to claim 2 wherein said gas permeable liquid impermeable membrane is fabricated from polypropylene.

Claim 21

An improved alkaline galvanic cell according to claim 2 wherein said gas permeable liquid impermeable membrane has a hydrogen gas permeability flow rate of about 40,000 to about 75, 000 cc per hour per square inch at 30 psi differential pressure at 20*C.

Claim 22

An improved alkaline galvanic cell according to claim 2 wherein said gas permeable liquid impermeable membrane has a liquid penetration differential pressure greater than about 300 psi.

Claim 23

An improved alkaline manganese dioxide cell according to claim 10 wherein said pressure movable resealable venting valve member is a disc having a material hardness of 30 to 80 durometer.

Claim 24

An improved alkaline manganese dioxide cell according to claim 10 where said pressure movable resealable venting valve member is a resilient deformable ball of an elastomeric material having a hardness of about 60 to 70 durometer.

Claim 25

An improved alkaline manganese dioxide cell according to claim 10 wherein said gas permeable liquid impermeable membrane has a hydrogen gas permeability flow rate of at least 20,000 cc per hour per square inch at 30 psi differential pressure at 20*C.

Claim 26

An improved alkaline manganese dioxide cell according to claim 10 wherein said gas permeable liquid impermeable membrane is fabricated from polypropylene.

Claim 27

An improved alkaline manganese dioxide cell according to claim 9 wherein said gas permeable liquid impermeable membrane is fabricated from polyethylene.

Claim 28

An improved alkaline manganese dioxide cell according to claim 10 wherein said gas permeable liquid impermeable membrane has a hydrogen gas permeability flow rate of about 40,000 to about 75,000 cc per hour per square inch at 30 psi differential pressure at 20*C.

Claim 29

An improved alkaline manganese dioxide cell according to claim 10 wherein said gas permeable liquid impermeable membrane has a liquid penetration differentiAl pressure greater than about 300 psi.

Claim 30

An improved alkaline galvanic cell according to claim 2 wherein said gas permeable liquid impermeable membrane is fabricated from a perhalogenated aliphatic hydrocarbon.

Claim 31

An improved alkaline galvanic cell according to claim 2 wherein said gas permeable liquid impermeable membrane has a burst strength below the rupture pressure point of the cell.