Cylindrical nickel-zinc cell with negative can
View Patent ↗A nickel-zinc battery cell is formed with a negative can, a positive cap, and a jelly roll of electrochemically active positive and negative materials within. The inner surface of the can is protected with an anticorrosive material that may be coated or plated onto the can. Good electrical contact between the jelly roll and the cap is achieved through folding the nickel substrate over to contact a positive current collection disk.
1. A nickel-zinc rechargeable battery cell, the battery comprising:
(a) a base metal can having a bottom and a cylindrical side, said base metal can comprising a first anticorrosive material coated, plated or clad onto the base metal can or residing between the base metal can and electrode material, the first anticorrosive material selected from the group consisting of tin, copper/tin alloy, zinc, silver, conductive carbon, brass, a non-wettable polymer layer and combinations thereof;
(b) a negative current collector disk disposed at the bottom of the can and in electrical contact with the can;
(c) a jelly roll comprising a positive electrode, a negative electrode, and one or more separators in between, said jelly roll is disposed above the negative current collector disk and said negative electrode is in electrical contact with the negative current collector disk;
(d) a positive current collector disk disposed above of the jelly roll and in electrical contact with the positive electrode;
(e) a vent assembly disposed on top of the positive current collector disk, said vent assembly is electrically connected with the positive current collector disk and electrically insulated from the can; and
(f) an alkaline electrolyte.
2. The cell of claim 1 , wherein the first anticorrosive material is zinc.
3. The cell of claim 1 , wherein the negative current collector disk comprises copper.
4. The cell of claim 3 , wherein the negative current collector disk is coated with a second anticorrosive material.
5. The cell of claim 4 , wherein the second anticorrosive material is selected from the group consisting of tin, copper/tin alloy, zinc, silver, conductive carbon, brass, and combinations thereof.
6. The cell of claim 1 , further comprising a spring mechanism disposed in between the negative current collector disk and the bottom of the can, said spring mechanism configured to absorb shock and vibration of the can.
7. The cell of claim 1 , wherein an outer layer of the jelly roll is the negative electrode.
8. The cell of claim 7 , wherein the outer layer electrically contacts the can.
9. The cell of claim 1 , wherein the can includes a beaded area above the jelly roll.
10. The cell of claim 9 , further comprising an insulator disposed above the jelly roll against the can below the beaded area.
11. The cell of claim 1 , wherein the positive electrode of the jelly roll comprises a nickel foam and a positive active material, said nickel foam folded over at the positive end of the jelly roll and lies between the positive current collector disk and the jelly roll, wherein the fold of each wind of the nickel foam overlaps another and the separator, such that the nickel foam forms a plate and does not electrically contact with the negative electrode.
12. The cell of claim 1 , wherein the vent assembly comprises a vent seal made of a hydrophobic gas permeable membrane.
13. The cell of claim 1 , wherein one or more tabs of the positive current collector disk are welded to the vent assembly.
14. The cell of claim 1 , wherein the vent assembly comprises a vent cap and a seal gasket, said seal gasket is not conductive and electrically insulates the vent assembly from the can.
15. The cell of claim 7 , wherein the first anticorrosive material is the non-wettable polymer layer attached to the outer layer of the jelly roll.
16. The cell of claim 15 , wherein the first anticorrosive material is attached to the separator extending beyond the last winding of the negative electrode.
17. The cell of claim 15 , wherein the first anticorrosive material comprises one or more hydrophobic polymer sheets.
18. The cell of claim 17 , wherein said one or more hydrophobic polymer sheets comprise a polyolefin microporous membrane.