LAYER CELL, ASSEMBLED BATTERY INCLUDING LAYER CELL, AND METHOD FOR ASSEMBLING LAYER CELL

• US 20140065470A1
• Filed: 11/29/2012
• Published: 03/06/2014
• Est. Priority Date: 12/19/2011
• Status: Active Grant

• Current Assignee: Exergy Power Systems, Inc.
• Original Assignee: Exergy Power Systems, Inc.
• Inventors: Tsutsumi, Kaduo, Nakoji, Masateru
• Granted Patent: US 9,876,251 B2
• Time in Patent Office: Days
• US Class Current: 429/164
• CPC Class Codes: C25B 1/02 Hydrogen or oxygen
• CPC Class Codes: H01M 10/04 Construction or manufacture in general H01M10/058, H01M10/12, H01M10/28, H01M10/38 take precedence
• CPC Class Codes: H01M 10/0422 Cells or battery with cylindrical casing
• CPC Class Codes: H01M 4/383 Hydrogen absorbing alloys
• CPC Class Codes: H01M 4/50 of manganese
• CPC Class Codes: H01M 4/75 Wires, rods or strips
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• CPC Class Codes: Y02P 70/50 Manufacturing or production processes characterised by the final manufactured product
• CPC Class Codes: Y10T 29/4911 including sealing

Abstract

Layer cell includes an outer casing, positive electrode, negative electrode, separator disposed between the positive electrode and the negative electrode, and electrically conductive current collector passing through the positive electrode, the negative electrode and the separator in an axial direction of the outer casing. The positive electrode, the negative electrode and the separator are stacked in the axial direction of the outer casing. First electrode which is one of the positive electrode and the negative electrode is in contact with an inner surface of the outer casing, but is not in contact with the current collector. Second electrode which is the other electrode is not in contact with the outer casing, but is in contact with the current collector. An outer edge of the second electrode is covered with the separator. Peripheral edge of a hole, in the first electrode is covered with the separator.

Claims

1. A layer cell comprising:

a tubular outer casing;

a positive electrode;

a negative electrode;

a separator disposed between the positive electrode and the negative electrode; and

an electrically conductive current collector passing through the positive electrode, the negative electrode and the separator in an axial direction of the outer casing, wherein

the positive electrode, the negative electrode and the separator are stacked in the axial direction of the outer casing,

a first electrode which is one of the positive electrode and the negative electrode comes into contact with an inner surface of the outer casing so as to be electrically connected to the inner surface of the outer casing, but is not in contact with the current collector,

a second electrode which is the other one of the positive electrode and the negative electrode is not in contact with the inner surface of the outer casing, but comes into contact with the current collector so as to be electrically connected to the current collector,

an outer edge of the separator is covered with the first electrode,

a peripheral edge of a hole, through which the current collector passes, in the separator is covered with the second electrode,

an outer edge of the second electrode is covered with the separator, and

a peripheral edge of a hole, through which the current collector passes, in the first electrode is covered with the separator.

2. The layer cell according to claim 1, wherein

the first electrode is enclosed with a bag-shaped first separator in a state that an outer edge of the first electrode is exposed at the outside of the first separator, and

the second electrode is enclosed with a bag-shaped second separator in a state that a peripheral edge of a hole, through which the current collector passes, in the second electrode is exposed at the outside of the second separator.

3. The layer cell according to claim 1, wherein

the current collector has a side surface on which a groove is formed,

a diameter of the narrowest portion of the current collector is larger than a diameter of the hole, through which the current collector passes, in the second electrode, and

a diameter of the thickest portion of the current collector is smaller than a diameter of the hole, through which the current collector passes, in the first electrode.

4. The layer cell according to claim 1, wherein

the negative electrode contains a hydrogen storage alloy.

5. The layer cell according to claim 4, wherein

each of the positive electrode and the negative electrode is an electrode that is charged and discharged, and is also an electrode that applies electrolysis to an electrolyte retained in the layer cell with an electric current fed from the outside.

6. The layer cell according to claim 4, wherein

a charge-capacity of the negative electrode is smaller than a charge-capacity of the positive electrode.

7. The layer cell according to claim 6, further comprising:

a hydrogen storage chamber disposed inside the outer casing, for storing hydrogen gas generated from the negative electrode.

8. The layer cell according to claim 7, wherein

the negative electrode is charged in such a manner that the hydrogen storage alloy contained in the negative electrode stores the hydrogen gas stored in the hydrogen storage chamber.

9. The layer cell according to claim 4, wherein

the positive electrode contains manganese dioxide.

10. The layer cell according to claim 7, wherein

the outer casing has a side portion formed into a cylindrical shape,

the outer casing has bulging portions that have a dome shape at axial two ends thereof, and

the hydrogen storage chamber is provided in each of the bulging portions.

11. An assembled battery comprising a plurality of layer cells according to claim 1, the layer cells being connected to each other via a columnar metal fitting, wherein

in each of the layer cells, the outer casing has a cylindrical body portion made of a metal, and lid portions for covering openings formed at axial two ends of the body portion, and the current collector passes through the lid portions,

the metal fittings has a top surface and a bottom surface each having a connection cavity formed thereon,

the end of the current collector in one of the layer cells is fittable into the connection cavity formed on the top surface of the metal fitting,

the end of the current collector in the different one of the layer cells adjoining the layer cell is fittable into the connection cavity formed on the bottom surface of the metal fitting, with an insulator interposed between the end and the connection cavity, and

the bottom surface of the metal fitting is electrically connected to the outer casing in the different layer cell.

12. An assembled battery comprising a plurality of layer cells according to claim 1, wherein

the outer casing in each of the layer cells has a one end-closed container having a rectangular section, and a lid member for covering an opening of the container, and

the layer cells are connected to each other such that the container in one of the layer cells and the lid member in the different one of the layer cells adjoining the layer cell are in surface contact with each other.

14. The layer cell according to claim 1, wherein

the first electrode is enclosed with a bag-shaped first separator in a state that an outer edge of the first electrode is exposed at the outside of the first separator.

15. The layer cell according to claim 1, wherein

the second electrode is enclosed with a bag-shaped second separator in a state that a peripheral edge of a hole, through which the current collector passes, in the second electrode is exposed at the outside of the second separator,

the positive electrode contains manganese dioxide.

13. A method for assembling a layer cell, comprising:

a first step of previously preparing a current collector having a side surface on which a screw groove is formed, and a round rod having a smaller outer diameter than a diameter of a root of a screw groove on the current collector;

a second step of assembling an electrode group in such a manner as to sequentially insert a positive electrode and a negative electrode into the round rod with a separator interposed between the positive electrode and the negative electrode and stack the electrodes;

a third step, to be carried out subsequent to the second step, of disposing presser plates on two ends of the electrode group to hold the electrode group and applying pressure to the presser plates to compress the electrode group;

a fourth step of pulling out the round rod while maintaining the compressed state;

a fifth step of pushing the current collector instead of the round rod into the electrode group while rotating the current collector, and then screwing the current collector into a screw hole formed on the center of the presser plate to assemble an electrode assembly while maintaining the compressed state of the electrode group;

a sixth step of putting the electrode assembly into the outer casing under pressure;

a seventh step of deaerating the outer casing;

an eighth step of injecting an electrolyte solution into the outer casing; and

a ninth step, to be carried out subsequent to the eighth step, of attaching a lid to the outer casing to seal the outer casing.