Rechargeable electrochemical cell and cell case therefor with vent for use in internal recombination of hydrogen and oxygen

Claim 2

A rechargeable electrochemical cell which has two modes of operation, a discharge mode in which electricity is produced and a recharge mode in which electrical energy is stored and hydrogen gas may be produced, the cell comprising: a. a case comprising a shell defining a case interior, the shell having a vent opening for receiving gas into the case or releasing gas from the case; b. a cathode disposed in the case; c. an anode disposed in the case; d. a liquid electrolyte disposed in the case and contacting the cathode and the anode; and e. a vent disposed in the case interior comprising: i. a gas permeable, electrolyte impermeable vent cover membrane having an interior surface facing the case interior and disposed in the case about the vent opening so as to prevent flow of electrolyte through the vent opening; ii. a foraminous catalyst support disposed in the case adjacent the interior surface of the vent cover membrane and facing the case interior; and iii. an oxygen/hydrogen recombination catalyst supported on the catalyst support for catalyzing the recombination of the hydrogen produced by the cell during the recharge mode with oxygen in the case interior to form water in the case interior.

Claim 3

A rechargeable electrochemical cell as in claim 1 wherein the vent defines a chamber within the shell for receiving or discharging air through the vent opening.

Claim 4

A rechargeable electrochemical cell as in claim 2 wherein the vent is dome-shaped.

Claim 5

A rechargeable electrochemical cell as in claim 1 wherein: the vent further comprises a vent support extending inwardly from the shell about the vent opening, having an interior surface facing the case interior, and having an opening for receiving gas into the case or releasing gas from the case through the vent opening; and the vent cover membrane extends over the interior surface of the vent support, covers the vent support opening, and is sandwiched between the catalyst support and the vent support.

Claim 6

A rechargeable electrochemical cell as in claim 4 wherein the vent support defines a chamber within the shell for receiving or discharging gas through the vent opening.

Claim 7

A rechargeable electrochemical cell as in claim 5 wherein the vent support is dome-shaped.

Claim 8

A rechargeable electrochemical cell as in claim 6 wherein the vent support has a plurality of openings.

Claim 9

A rechargeable electrochemical cell as in claim 4 wherein: the vent support has a round base with a recessed portion encircling the base adjacent the shell; and the catalyst support comprises a ring and a foraminous screen encompassed by the ring, the screen fitting over the vent support and vent cover membrane and the ring received within the recessed portion of the base to clamp the catalyst support to the vent support and sandwich the vent cover membrane between the catalyst support and the vent support.

Claim 10

A rechargeable electrochemical cell as in claim 1 wherein the shell and vent support are plastic.

Claim 11

A rechargeable electrochemical cell as in claim 4 wherein the shell and vent support are plastic.

Claim 12

A rechargeable electrochemical cell as in claim 1 wherein the vent cover membrane comprises a microporous polymer membrane.

Claim 13

A rechargeable electrochemical cell as in claim 4 wherein the vent cover membrane comprises a microporous polymer membrane.

Claim 14

A rechargeable electrochemical cell as in claim 1 wherein the catalyst comprises a noble metal.

Claim 15

A rechargeable electrochemical cell as in claim 4 wherein the catalyst comprises a noble metal.

Claim 16

A rechargeable electrochemical cell as in claim 1 wherein the catalyst is selected from the group consisting of platinum, platinized carbon, and rhodium.

Claim 17

A rechargeable electrochemical cell as in claim 4 wherein the catalyst is selected from the group consisting of platinum, platinized carbon, and rhodium.

Claim 18

A rechargeable electrochemical cell as in claim 1 wherein the shell has an anode panel proximate the anode and a cathode panel proximate the cathode and the vent extends into the case interior from the anode panel.

Claim 19

A rechargeable electrochemical cell as in claim 4 wherein the shell has an anode panel proximate the anode and a cathode panel proximate the cathode and the vent extends into the case interior from the anode panel.

Claim 20

A rechargeable electrochemical cell as in claim 1 wherein the shell further comprises a substantially planar anode panel and a substantially planar cathode panel, spaced from and substantially parallel to the anode panel, so that the case is prismatic in shape, and wherein the vent extends into the case interior from the anode panel.

Claim 21

A rechargeable electrochemical cell as in claim 4 wherein the shell further comprises a substantially planar anode panel and a substantially planar cathode panel, spaced from and substantially parallel to the anode panel, so that the case is prismatic in shape, and wherein the vent extends into the case interior from the anode panel.

Claim 22

A rechargeable metal-air electrochemical cell which has two modes of operation, a discharge mode in which electricity is produced and a recharge mode in which electrical energy is stored and hydrogen gas may be produced, the cell comprising: a. a case comprising a shell defining a case interior, the shell having a vent opening for receiving gas into the case or releasing gas from the case; b. an air cathode disposed in the case; c. an anode disposed in the case; d. an aqueous electrolyte disposed in the case and contacting the air cathode and the anode; and e. a vent disposed in the case interior comprising: i. a gas permeable, electrolyte impermeable vent cover membrane having an interior surface facing the case interior and disposed in the case about the vent opening so as to prevent the flow of electrolyte through the vent opening; ii. a foraminous catalyst support disposed in the case adjacent the interior surface of the vent cover membrane, and facing the case interior; and iii. an oxygen/hydrogen recombination catalyst supported on the catalyst support for catalyzing the recombination of the hydrogen produced by the cell during the recharge mode with oxygen in the cell interior to form water in the cell interior.

Claim 23

A rechargeable metal-air electrochemical cell which has two modes of operation, a discharge mode in which electricity is produced and a recharge mode in which electrical energy is stored and hydrogen gas may be produced, the cell comprising: a. a case comprising a shell defining a case interior, the shell having a vent opening for receiving gas into the case or releasing gas from the case; b. an air cathode disposed in the case; c. an anode disposed in the case; d. an aqueous electrolyte disposed in the case and contacting the air cathode and the anode; and e. a vent disposed in the case interior comprising: i. a gas permeable, electrolyte impermeable vent cover membrane having an interior surface facing the case interior and disposed in the case about the vent opening so as to prevent the flow of electrolyte through the vent opening; ii. a foraminous catalyst support disposed in the case adjacent the interior surface of the vent cover membrane, and facing the case interior; and iii. an oxygen/hydrogen recombination catalyst supported on the catalyst support for catalyzing the recombination of the hydrogen produced by the cell during the recharge mode with oxygen in the cell interior to form water in the cell interior.

Claim 24

A rechargeable metal-air electrochemical cell as in claim 21 wherein the vent defines a chamber within the shell for receiving or discharging air through the vent opening.

Claim 25

A rechargeable metal-air electrochemical cell as in claim 22 wherein the vent is dome-shaped.

Claim 26

A rechargeable metal-air electrochemical cell as in claim 1 wherein: the vent further comprises a vent support extending inwardly from the shell about the vent opening, having an interior surface facing the case interior, and having an opening for receiving gas into the case or releasing gas from the case through the vent opening; and the vent cover membrane extends over the interior surface of the vent support, covers the vent support opening, and is sandwiched between the catalyst support and the vent support.

Claim 27

A rechargeable metal-air electrochemical cell as in claim 24 wherein the vent support defines a chamber within the shell for receiving or discharging air through the vent opening.

Claim 28

A rechargeable metal-air electrochemical cell as in claim 25 wherein the vent support is dome-shaped.

Claim 29

A rechargeable metal-air electrochemical cell as in claim 26 wherein the vent support has a plurality of openings.

Claim 30

A rechargeable metal-air electrochemical cell as in claim 24 wherein: the vent support has a round base with a recessed portion encircling the base adjacent the shell; and the catalyst support comprises a ring and a foraminous screen encompassed by the ring, the screen fitting over the vent support and vent cover membrane and the ring received within the recessed portion of the base to clamp the catalyst support to the vent support and sandwich the vent cover membrane between the catalyst support and the vent support.

Claim 31

A rechargeable metal-air electrochemical cell as in claim 21 wherein the shell and vent support are plastic.

Claim 32

A rechargeable metal-air electrochemical cell as in claim 24 wherein the shell and vent support are plastic.

Claim 33

A rechargeable metal-air electrochemical cell as in claim 21 wherein the vent cover membrane comprises microporous polymer membrane.

Claim 34

A rechargeable metal-air electrochemical cell as in claim 24 wherein the vent cover membrane comprises microporous polymer membrane.

Claim 35

A rechargeable metal-air electrochemical cell as in claim 21 wherein the catalyst comprises a noble metal.

Claim 36

A rechargeable metal-air electrochemical cell as in claim 24 wherein the catalyst comprises a noble metal.

Claim 37

A rechargeable metal-air electrochemical cell as in claim 21 wherein the catalyst is selected from the group consisting of platinum, platinized carbon, and rhodium.

Claim 38

A rechargeable metal-air electrochemical cell as in claim 24 wherein the catalyst is selected from the group consisting of platinum, platinized carbon, and rhodium.

Claim 39

A rechargeable metal-air electrochemical cell as in claim 21 wherein the shell has an anode panel proximate the anode and a cathode panel proximate the air cathode and the vent extends into the case interior from the anode panel.

Claim 40

A rechargeable metal-air electrochemical cell as in claim 24 wherein the shell has an anode panel proximate the anode and a cathode panel proximate the air cathode and the vent extends into the case interior from the anode panel.

Claim 41

A rechargeable metal-air electrochemical cell as in claim 21 wherein the shell further comprises a substantially planar anode panel and a substantially planar cathode panel, spaced from and substantially parallel to the anode panel, so that the case is prismatic in shape, and wherein the vent extends into the case interior from the anode panel.

Claim 42

A rechargeable metal-air electrochemical cell as in claim 24 wherein the shell further comprises a substantially planar anode panel and a substantially planar cathode panel, spaced from and substantially parallel to the anode panel, so that the case is prismatic in shape, and wherein the vent extends into the case interior from the anode panel.

Claim 43

A case for a rechargeable electrochemical cell which has two modes of operation, a discharge mode in which electricity is produced and a recharge mode in which electrical energy is stored and hydrogen gas may be produced, the case comprising: a. a shell defining a case interior and having a vent opening for receiving gas into the case or releasing gas from the case; and b. a vent disposed in the case interior and comprising: i. a gas permeable, electrolyte impermeable vent cover membrane having an interior surface facing the case interior and disposed in the case about the vent opening so as to prevent flow of electrolyte through the vent opening; ii. a foraminous catalyst support disposed in the case adjacent the interior surface of the vent cover membrane and facing the case interior; and iii. an oxygen/hydrogen recombination catalyst supported on the catalyst support for catalyzing the recombination of the hydrogen produced by the cell during the recharge mode with oxygen in the case interior to form water in the case interior.

Claim 44

A case for a rechargeable electrochemical cell which has two modes of operation, a discharge mode in which electricity is produced and a recharge mode in which electrical energy is stored and hydrogen gas may be produced, the case comprising: a. a shell defining a case interior and having a vent opening for receiving gas into the case or releasing gas from the case; and b. a vent disposed in the case interior and comprising: i. a gas permeable, electrolyte impermeable vent cover membrane having an interior surface facing the case interior and disposed in the case about the vent opening so as to prevent flow of electrolyte through the vent opening; ii. a foraminous catalyst support disposed in the case adjacent the interior surface of the vent cover membrane and facing the case interior; and iii. an oxygen/hydrogen recombination catalyst supported on the catalyst support for catalyzing the recombination of the hydrogen produced by the cell during the recharge mode with oxygen in the case interior to form water in the case interior.

Claim 45

A case as in claim 41 wherein the vent defines a chamber within the shell for receiving or discharging air through the vent opening.

Claim 46

A case as in claim 42 wherein the vent is dome-shaped.

Claim 47

A case as in claim 41 wherein: the vent further comprises a vent support extending inwardly from the shell about the vent opening, having an interior surface facing the case interior, and having an opening for receiving gas into the case or releasing gas from the case through the vent opening; and the vent cover membrane extends over the interior surface of the vent support, covers the vent support opening, and is sandwiched between the catalyst support and the vent support.

Claim 48

A case as in claim 44 wherein the vent support defines a chamber within the shell for receiving or discharging gas through the vent opening.

Claim 49

A case as in claim 45 wherein the vent support is dome-shaped.

Claim 50

A case as in claim 46 wherein the vent support has a plurality of openings.

Claim 51

A case as in claim 44 wherein: the vent support has a round base with a recessed portion encircling the base adjacent the shell; and the catalyst support comprises a ring and a foraminous screen encompassed by the ring, the screen fitting over the vent support and vent cover membrane and the ring received within the recessed portion of the base to clamp the catalyst support to the vent support and sandwich the vent cover membrane between the catalyst support and the vent support.

Claim 52

A case as in claim 41 wherein the shell and vent support are plastic.

Claim 53

A case as in claim 44 wherein the shell and vent support are plastic.

Claim 54

A case as in claim 41 wherein the vent cover membrane comprises a microporous polymer membrane.

Claim 55

A case as in claim 44 wherein the vent cover membrane comprises a microporous polymer membrane.

Claim 56

A case as in claim 41 wherein the catalyst comprises a noble metal.

Claim 57

A case as in claim 44 wherein the catalyst comprises a noble metal.

Claim 58

A case as in claim 41 wherein the catalyst is selected from the group consisting of platinum, platinized carbon, and rhodium.

Claim 59

A case as in claim 44 wherein the catalyst is selected from the group consisting of platinum, platinized carbon, and rhodium.

Claim 60

A case as in claim 41 wherein the shell further comprises a substantially planar anode panel and a substantially planar cathode panel, spaced from and substantially parallel to the anode panel, so that the case is prismatic in shape, and wherein the vent extends into the case interior from the anode panel.

Claim 61

A case as in claim 44 wherein the shell further comprises a substantially planar anode panel and a substantially planar cathode panel, spaced from and substantially parallel to the anode panel, so that the case is prismatic in shape, and wherein the vent extends into the case interior from the anode panel.