Bipolar unit cell, method for manufacturing the same, and bipolar battery including the same

Abstract

According to one embodiment of the present invention, a bipolar unit cell is provided, comprising a positive electrode including a positive electrode current collector and a positive electrode material layer formed on one surface of the positive electrode current collector such that a blank positive electrode portion is formed on the frame; a negative electrode including a negative electrode current collector and a negative electrode material layer formed on one surface of the negative electrode current collector such that a blank negative electrode portion is formed on the frame; and a separation membrane, wherein the positive electrode material layer and the negative electrode material layer are stacked facing each other with the separation membrane in between, and one or more of the group consisting of the positive electrode material layer, the negative electrode material layer, and the separation membrane contains a cured gel electrolyte; a method for manufacturing the same; and a bipolar battery having a structure in which two or more of the bipolar unit cells are stacked.

Claims

1. A positive electrode comprising a positive electrode current collector and a positive electrode material layer formed on one surface of the positive electrode current collector such that a blank positive electrode portion is formed on the frame, A negative electrode comprising a negative electrode current collector and a negative electrode material layer formed on one surface of the negative electrode current collector such that a blank negative electrode portion is formed on the frame, Includes a separation membrane, The positive electrode material layer and the negative electrode material layer are stacked facing each other with a separation film in between. A bipolar unit cell in which one or more components selected from the group consisting of the positive electrode layer, the negative electrode layer, and the separation membrane contain a cured gel electrolyte.

2. The bipolar unit cell according to claim 1, wherein the positive electrode, the negative electrode, and the separation membrane are bonded to each other by the cured gel electrolyte.

3. A bipolar unit cell according to claim 1, wherein a positive electrode insulating layer is formed on the blank positive electrode portion, and a negative electrode insulating layer is formed on the blank negative electrode portion.

4. The bipolar unit cell according to claim 1, wherein a conductive layer is formed on at least one of the other surfaces of the positive electrode current collector and the other surface of the negative electrode current collector.

5. The bipolar unit cell according to claim 4, wherein the conductive layer is formed over an area of ​​90% to 100% of the exposed area of ​​the other side of the positive electrode current collector or the other side of the negative electrode current collector.

6. The bipolar unit cell according to claim 4, wherein the conductive layer is a conductive tape or conductive sealant containing copper or carbon.

7. The bipolar unit cell according to claim 1, further comprising a sealing member for sealing the opening between the positive electrode current collector and the negative electrode current collector.

8. The bipolar unit cell according to claim 7, wherein the sealing member is a polymer film formed on the inside of the opening between the positive electrode current collector and the negative electrode current collector, or in a form that connects the other surface of the positive electrode current collector and the other surface of the negative electrode current collector.

9. The bipolar unit cell according to claim 1, wherein the positive electrode material layer is a dry positive electrode.

10. The bipolar unit cell according to claim 1, wherein the positive electrode current collector is an Al current collector and the negative electrode current collector is a Cu current collector.

11. A method for manufacturing a bipolar unit cell as described in claim 1, (a) Prepare the positive and negative electrodes by forming a positive electrode material layer on one surface of the positive electrode current collector so that a blank positive electrode area is formed on the frame, and a negative electrode material layer on one surface of the negative electrode current collector so that a blank negative electrode area is formed on the frame, and prepare the separation membrane, (b) Impregnating one or more gel electrolyte compositions selected from the group consisting of the positive electrode material layer, the negative electrode material layer, and the separation membrane, (c) A method for manufacturing a bipolar unit cell, comprising laminating the positive electrode material layer and the negative electrode material layer with the separation membrane interposed between the positive electrode and the negative electrode in a state where the positive electrode material layer and the negative electrode material layer face each other, and then curing the gel electrolyte composition.

12. The method for manufacturing a bipolar unit cell according to claim 11, wherein the positive electrode, the negative electrode, and the separation membrane are bonded and integrated by curing of the gel electrolyte.

13. The method for manufacturing a bipolar unit cell according to claim 11, wherein, when impregnating the positive electrode material layer or the negative electrode material layer with the gel electrolyte composition, the method is carried out with masking tape attached to one or more of the blank portions of the positive electrode and the blank portions of the negative electrode.

14. The method for manufacturing the bipolar unit cell is as follows: A method for manufacturing a bipolar unit cell according to claim 11, further comprising forming a positive electrode insulating layer on the positive electrode blank portion and forming a negative electrode insulating layer on the negative electrode blank portion.

15. The method for manufacturing the bipolar unit cell is as follows: The method for manufacturing a bipolar unit cell according to claim 11, further comprising forming a conductive layer on at least one of the other surfaces of the positive electrode current collector and the other surface of the negative electrode current collector.

16. The method for manufacturing a bipolar unit cell according to claim 11, further comprising sealing the opening between the positive electrode current collector and the negative electrode current collector with a sealing member after (c) above.

17. The method for manufacturing a bipolar unit cell according to claim 11, wherein the positive electrode material layer is formed by dry mixing a positive electrode active material, a conductive agent, and a binder containing a fibrous polymer, molding this into a freestanding film, and then adhering it to one surface of the positive electrode current collector.

18. A bipolar battery having a structure in which two or more of the bipolar unit cells described in any one of claims 1 to 10 are stacked, The aforementioned bipolar unit cells are stacked so that current collectors with opposite polarities face each other, forming a bipolar battery.

19. The bipolar battery according to claim 18, wherein a conductive layer is located between the two or more unit cells, and the bipolar unit cells are bonded to each other by the conductive layer.

20. The bipolar battery according to claim 18, wherein electrode terminals are formed on the outermost electrode of the outermost bipolar unit cell among the bipolar unit cells.

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