Nickel-hydrogen secondary battery

Claim 2

In a nickel-hydrogen secondary battery comprising a single or multi-cell array with each cell made up of at least a nickel oxi-hydroxide cathode plate, a hydrogen anode plate a separator containing a liquid electrolyte disposed between and extending from the anode plate to the cathode plate, and a hydrogen ambient atmosphere which is accessible to the anode plate, so that said electrolyte provides a conductive path between said cathode and anode plates and energy conversion is effected through charge and discharge in accordance with the simplified reversible overall equation, NiOOH + 1/2 H.sub.2 ⃡Ni(OH).sub.2 the improvement comprising means defining an oxygen return path between the ends of each cell to prevent an asymmetric buildup of oxygen produced during charging said oxygen recombining with hydrogen.

Claim 3

The improved secondary battery of claim 1 wherein the cells of an array are arranged with single positives (cathodes) such as to allow part or all of the oxygen generated at the cathode of one cell to reach the anode of the following cell unit by diffusion.

Claim 4

In a nickel-hydrogen battery which is capable of being charged and discharged in accordance with the simplified overall reversible reaction equation NiOOH + 1/2H.sub.2 ⃡Ni(OH).sub.2 and which comprises at least two unit cells with each cell comprising a nickel oxi-hydroxide cathode plate having first and second opposite sides, a hydrogen anode plate having first and second opposite sides, separator means containing a liquid electrolyte extending between the first side of said cathode plate and the first side of said anode plate so as to provide a conductive path therebetween, and a porous gas-distributor means located adjacent to the second side of said anode plate for conducting an ambient hydrogen atmosphere to said anode plate; the improvement comprising means defining a reservoir for receiving electrolyte which is displaced from within each cell as a result of gas evolution and for returning said electrolyte to said each cell, said reservoir-defining means comprising a porous member disposed in engaging relation with the second side of said cathode plate and non-engaging relation with any anode plate in said battery.

Claim 5

In a nickel-hydrogen battery which is capable of being charged and discharged in accordance with the simplified overall reversible reaction equation NiOOH + 1/2H.sub.2 ⃡Ni(OH).sub.2 and which comprises at least two unit cells with each cell comprising a nickel oxi-hydroxide cathode plate having first and second opposite sides, a hydrogen anode plate having first and second opposite sides, separator means containing a liquid electrolyte extending between the first side of said cathode plate and the first side of said anode plate so as to provide a conductive path therebetween, and a porous gas-distributor means located adjacent to the second side of said anode plate for conducting an ambient hydrogen atmosphere to said anode plate; the improvement comprising means defining a reservoir for receiving electrolyte which is displaced from within each cell as a result of gas evolution and for returning said electrolyte to said each cell, said reservoir-defining means comprising a porous member disposed in engaging relation with the second side of said cathode plate and non-engaging relation with any anode plate in said battery.

Claim 6

An improved battery according to claim 3 wherein said cells are disposed so that a cathode plate of one cell is in back-to-back relation with a cathode plate of another cell, and said reservoir-defining means extends between said back-to-back cathode plates.

Claim 7

An improved battery according to claim 4 wherein said reservoir-defining means comprises two porous members located between said back-to-back cathode plates, and further including at least one membrane separating said porous members.

Claim 8

An improved battery according to claim 5 wherein said membrane is gas permeable.

Claim 9

An improved battery according to claim 6 wherein said membrane is a microporous hydrophobic material.

Claim 10

An improved battery according to claim 5 having at least two membranes separating said porous members.

Claim 11

An improved battery according to claim 3 wherein said cells are in a stacked array, with said reservoir-defining means comprising a separate porous member for each cell.

Claim 12

An improved battery according to claim 3 wherein said separator means and said reservoir-defining means comprise porous members with the pores of said reservoir-defining means having a larger average size than the pores of said separator means.

Claim 13

An improved battery according to claim 3 wherein said cells are arranged in a stack, and further including means providing a path for equilibrating electrolyte liquid between the ends of each cell to prevent imbalance of accumulating water generated by reaction of oxygen with hydrogen.

Claim 14

In a nickel-hydrogen battery which is capable of being charged and discharged in accordance with the simplified overall reversible reaction equation NiOOH + 1/2H.sub.2 ⃡Ni(OH).sub.2 and which comprises one or more nickel oxi-hydroxide cathode plates and one or more anode plates each having first and second sides, separator means containing a liquid electrolyte extending between the first side of each cathode plate and the first side of each anode plate that is adajcent to each said cathode plate so as to provide a conductive path therebetween, and porous gas-distributor means located adjacent to the second side of each anode plate for conducting an ambient hydrogen atmosphere to each anode plate; the improvement comprising means defining a reservoir for receiving electrolyte which is displaced from its normal location in each cathode plate and each separator means as a result of gas evolution and for returning said electrolyte to said normal location, said reservoir-defining means being porous and disposed in engaging relation with the second side of each cathode plate and non-engaging relation with any anode plate and any separator means.

Claim 15

In a nickel-hydrogen battery which is capable of being charged and discharged in accordance with the simplified overall reversible reaction equation NiOOH + 1/2H.sub.2 ⃡Ni(OH).sub.2 and which comprises one or more nickel oxi-hydroxide cathode plates and one or more anode plates each having first and second sides, separator means containing a liquid electrolyte extending between the first side of each cathode plate and the first side of each anode plate that is adajcent to each said cathode plate so as to provide a conductive path therebetween, and porous gas-distributor means located adjacent to the second side of each anode plate for conducting an ambient hydrogen atmosphere to each anode plate; the improvement comprising means defining a reservoir for receiving electrolyte which is displaced from its normal location in each cathode plate and each separator means as a result of gas evolution and for returning said electrolyte to said normal location, said reservoir-defining means being porous and disposed in engaging relation with the second side of each cathode plate and non-engaging relation with any anode plate and any separator means.

Claim 16

An improved battery according to claim 12 comprising at least two unit cells each having a nickel oxy-hydroxide cathode plate, an anode plate and an electrolyte-containing separator means extending between its said cathode and anode plates, said cells being disposed so that a cathode plate of one cell is in back-to-back relation with a cathode plate of the other cell, and said reservoir-defining means extends between said back-to-back cathode plates.

Claim 17

An improved battery according to claim 13 wherein said reservoir-defining means comprises two porous members located between said back-to-back cathode plates, and further including at least one membrane separating said porous members.

Claim 18

An improved battery according to claim 12 comprising at least first and second unit cells with each cell having a nickel oxy-hydroxide cathode plate, an anode plate, an electrolyte-containing separator means between its said cathode and anode plates, a separate reservoir-defining means in the form of a porous member, and a separate gas distributor means, said cells being arranged with their components stacked together in the following order: first cell gas distributor means, first cell anode plate, first cell separator means, first cell cathode plate, first cell reservoir means, second cell gas distributor means, second cell anode plate, second cell separator means, second cell cathode plate, and second cell reservoir means.

Claim 19

An improved battery according to claim 15 wherein said first cell also comprises a gas-porous, electrolyte-impermeable membrane located between said first cell reservoir means and said second cell gas distributor means.

Claim 20

An improved nickel-hydrogen battery which is capable of being charged and discharged in accordance with the simplified overall reversible reaction represented by the equation NiOOH + 1/2H.sub.2 ⃡Ni(OH).sub.2 and which comprises at least two unit cells each having a nickel oxi-hydroxide cathode plate, a hydrogen-containing anode plate, and a separator containing an aqueous liquid electrolyte extending between said cathode and anode plates, said cells being arranged in a stack with their cathode and anode plates arranged in the same order, and means extending lengthwise of the stack for providing a predetermined path for retrieving electrolyte liquid accumulating in one cell in the stack and transferring it to another cell in the same stack so as to prevent imbalance of accumulating water generated by reaction of oxygen with hydrogen.

Claim 21

An improved nickel-hydrogen battery which is capable of being charged and discharged in accordance with the simplified overall reversible reaction represented by the equation NiOOH + 1/2H.sub.2 ⃡Ni(OH).sub.2 and which comprises at least two unit cells each having a nickel oxi-hydroxide cathode plate, a hydrogen-containing anode plate, and a separator containing an aqueous liquid electrolyte extending between said cathode and anode plates, said cells being arranged in a stack with their cathode and anode plates arranged in the same order, and means extending lengthwise of the stack for providing a predetermined path for retrieving electrolyte liquid accumulating in one cell in the stack and transferring it to another cell in the same stack so as to prevent imbalance of accumulating water generated by reaction of oxygen with hydrogen.

Claim 22

In a nickel-hydrogen battery which is capable of being charged and discharged in accordance with the simplified overall reversible reaction equation NiOOH + 1/2H.sub.2 ⃡Ni(OH).sub.2 and which comprises at least two unit cells arranged in a stack with each cell comprising a nickel oxi-hydroxide cathode plate, a hydrogen anode plate, separator means containing a liquid electrolyte extending between said cathode plate and said anode plate so as to provide a conductive path therebetween, and a porous gas-distributor means located adjacent to said anode plate for conducting an ambient hydrogen atmosphere to said anode plate; the improvement comprising means defining a reservoir for receiving electrolyte which is displaced from within each cell as a result of gas evolution and for returning said electrolyte to said each cell, said reservoir-defining means being porous and disposed in engaging relation with each cathode plate and non-engaging relation with any anode plate, and means providing an oxygen return path between the ends of the cells to prevent imbalance of accummulating oxygen in the cells said oxygen recombining with hydrogen.

Claim 23

In a nickel-hydrogen battery which is capable of being charged and discharged in accordance with the simplified overall reversible reaction equation NiOOH + 1/2H.sub.2 ⃡Ni(OH).sub.2 and which comprises at least two unit cells arranged in a stack with each cell comprising a nickel oxi-hydroxide cathode plate, a hydrogen anode plate, separator means containing a liquid electrolyte extending between said cathode plate and said anode plate so as to provide a conductive path therebetween, and a porous gas-distributor means located adjacent to said anode plate for conducting an ambient hydrogen atmosphere to said anode plate; the improvement comprising means defining a reservoir for receiving electrolyte which is displaced from within each cell as a result of gas evolution and for returning said electrolyte to said each cell, said reservoir-defining means being porous and disposed in engaging relation with each cathode plate and non-engaging relation with any anode plate, and means providing an oxygen return path between the ends of the cells to prevent imbalance of accummulating oxygen in the cells said oxygen recombining with hydrogen.