Fast rechargeable sealed nickel-cadmium battery cells combined with excess pressure and temperature controls

Claim 2

A rechargeable battery cell as set forth in claim 1, said pressure release wall section being located at a casing portion other than said deflectable wall section.

Claim 3

A rechargeable battery cell as set forth in claim 1, said predetermined maximum level of vent opening exceeding said predetermined switching level by a specified magnitude.

Claim 4

A rechargeable battery cell as claimed in claim 2, said deflectable wall section constituting a diaphragm having a rim, endless insulating elements joining said rim with a leaktight seal to nearby portions of said casing, said diaphragm having said vent passage to said casing interior, and sealing body including an endless elastomer loop of substantial cross section carried by said diaphragm and held with a tight seal against said vent passage and normally preventing gas release from said casing, at least portions of said loop undergoing said deformation and opening said seal at said maximum pressure, and restoring said seal below said maximum pressure.

Claim 5

A rechargeable cell as claimed in claim 5, said diaphragm having an intermediate barrier section having said vent passage.

Claim 6

A rechargeable battery cell as claimed in claim 6, said diaphragm having an intermediate barrier section having said vent passage, and retainer elements carried by said barrier section and defining therewith two opposite endless sealing surfaces of said vent passage, said loop being held by said restraint elements with said tight seal against opposite endless seating surfaces.

Claim 7

A rechargeable battery cell as claimed in claim 7, said diaphragm having an intermediate barrier section having said vent passage, and metallic retainer sheet elements carried by said barrier section and defining therewith two opposite endless sealing surfaces of said vent passage, said loop being held by said restraint elements with said tight seal against opposite endless seating surfaces.

Claim 8

A rechargeable battery cell as claimed in claim 7, said diaphragm having an intermediate barrier section having said vent passage, and retainer elements carried by said barrier section and defining therewith two opposite endless sealing surfaces of said vent passage, said loop being held by said restraint elements with said tight seal against opposite endless seating surfaces, said retainer element having rim portions embracing and at least partially compressing said loop against said sealing surfaces.

Claim 9

A rechargeable cell as claimed in claim 7, said diaphragm having an intermediate barrier section having said vent passage, and metallic retainer sheet elements carried by said barrier section and defining therewith two opposite endless sealing surfaces of said vent passage, said loop being held by said restraint elements with said tight seal against opposite endless seating surfaces, said retainer element having rim portions embracing and at least partially compressing said loop against said sealing surfaces.

Claim 10

In a rechargeable battery cell as claimed in claim 3, said deflecTable wall section constituting a diaphragm having a rim, an endless insulating loop joining with a tight seal and diaphragm rim to a nearby wall portion of said casing, a casing portion remote from said diaphragm having said vent passage, and carrying said polymer body.

Claim 11

A rechargeable battery cell comprising a normally sealed casing having at least two opposite polarity exposed relatively insulated metallic casing wall portions, an electrolyte-containing electrode assembly with at least two opposite polarity electrodes enclosed in said casing and tending to develop excessive internal pressure within the casing interior under certain operating conditions, said two electrodes having connections to said two exposed casing wall portions, respectively, said electrode assembly holding at most 90 percent of the electrolyte volume required to substantially saturate the pores of said electrode assembly, said electrode assembly being formed of electrode plates, the negative plate having a face at least covering the face of the adjacent positive plate and a charge capacity at least 70 percent greater than that of said positive plate causing said positive plate to absorb the major gas volume part developed when the assembly is recharged within three hours from a fully discharged state, said casing having a deflectable wall section elastically biased to an inward position, and undergoing movement to an outward circuit-control position upon internal casing pressure rising to a certain raised initial pressure, and return movement to said inward position upon said internal pressure becoming lower than said initial pressure, said deflectable wall section being part of one of said wall portions, said wall section having at least one vent passage to the casing interior for releasing gases, a polymer sealing body including elastic restraint elements carried on the exterior of said wall section with a tight seal against said vent passage, and preventing release of gases through said vent passage past said polymer body up to a certain raised initial internal gas pressure in said casing, at least a portion of said polymer body undergoing deformation and opening said seal with said vent passage and releasing gases past said polymer body upon said internal pressure rising to a certain maximum exceeding said initial pressure, said elastic restraint elements causing said polymer body to restore said seal with said vent passage and preventing release of gases upon said internal pressure becoming lower than said maximum

Claim 12

A rechargeable cell as claimed in claim 12, said deflectable wall section constituting a diaphragm having a rim, endless insulating elements joining said rim with a leaktight seal to nearby portions of said casing, said diaphragm having said vent passage to said casing interior, and sealing body including an endless elastomer loop of substantial cross section carried by said diaphragm and held with a tight seal against said vent passage and normally preventing gas release from said casing, at least portions of said loop undergoing said deformation and opening said seal at said maximum pressure, and restoring said seal below said maximum pressure.

Claim 13

A rechargeable cell as claimed in claim 13, said diaphragm consisting essentially of metal and having a barrier section having said vent passage, and metallic retainer sheet elements carried by said barrier section and defining therewith two opposite endless sealing surfaces of said vent passage, said loop being held by said restraint elements with said tight seal against opposite endless sealing surfaces.

Claim 14

A rechargeable battery cell, comprising a normally sealed casing having at least two opposite polarity exposed relatively insulated metallic casing wall portions, an electrolyte-containing electrode assembly with at least two opposite polarity electrodes encloSed in said casing and tending to develop excessive internal pressure within the casing interior under certain operating conditions, said two electrodes having connections to said two exposed casing wall portions, respectively, said electrode assembly holding at most 90 percent of the electrolyte volume required to substantially saturate the pores of said electrode assembly, said electrode assembly being formed of electrode plates, and the negative plate having a face at least covering the face of the adjacent positive plate and a charge capacity at least 70 percent greater than that of said positive plate causing said positive plate to absorb the major gas volume part developed when the assembly is recharged within three hours from a fully discharged state, said casing having a deflectable wall section elastically biased to an inward position, and undergoing movement to an outward circuit-control position upon internal casing pressure rising to a certain raised initial pressure, and return movement to said inward position upon said internal pressure becoming lower than said initial pressure, a further casing portion other than said deflectable wall section having vent passage to the casing exterior for releasing excess pressure gases, a polymer sealing body including elastic restraint elements carried on the interior of said casing portion with a tight seal against said vent passage, and preventing release of gases through said vent passage past said polymer body up to a certain raised maximum internal gas pressure in said casing higher than said initial pressure, at least a portion of said polymer body undergoing deformation and opening said seal with said vent passage and releasing gases past said polymer body upon said internal pressure rising to said maximum initial pressure, said elastic restraint elements causing said polymer body to restore said seal with said vent passage and preventing release of gases upon said internal pressure becoming lower than said maximum.

Claim 15

A rechargeable cell comprising, a sealed container, electrodes within said container, electrolyte within said container, means for relieving pressure developing within said container, and means responsive to charging conditions within said container for providing a movement on the exterior of said cell whereby such movement may be used to discontinue fast charging and start a slow charge.

Claim 16

A rechargeable cell according to claim 16 wherein said means responsive to charging conditions is responsive to pressure which is developed within said container during charging.

Claim 17

A rechargeable cell according to claim 16 wherein said means responsive to charging conditions is responsive to temperature which is developed within said container during charging.

Claim 18

A rechargeable cell according to claim 16 wherein said means responsive to charging conditions includes a diaphragm extending across one end of said container exposed to conditions within said container on one side thereof and to external conditions on the other side thereof, means connecting to said diaphragm to provide for the actuation of a switch.