JP2972968B2 - Laminated cell and method of manufacturing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laminated structure of cells such as a button type battery or an electric double layer capacitor used as a main power supply or a sub power supply of various electronic devices.

[0002]

2. Description of the Related Art Conventional button-type batteries or button-type electric double-layer capacitors (hereinafter referred to as cells) of this type often require a high voltage depending on the application of electronic equipment using them. As shown in the cross-sectional view of FIG. 3, two or more cells were stacked in series and integrated. In this conventional example, a connection terminal C7 made of a cylindrical can is laser-welded on the negative electrode can 1 of the cell B20 at a welding point 5b, and then the cell A10 is inserted into the connection terminal C. The cell A and the connection terminal C are irradiated with a laser from the side surface of the connection terminal C in order to secure electrical connection, and the anode can 2 of the cell A and the connection terminal C are welded at a welding point 5d. I have.

Incidentally, reference numeral 6 denotes a laser beam. Such a prior art is disclosed in JP-A-63-268219 and JP-A-63-268222.

[0004]

In the prior art, it is necessary to increase the fitting accuracy between the outer diameter of the cell and the inner diameter of the connection terminal C. If the gap between the outer diameter of the cell and the inner diameter of the connection terminal C is too large, there is a disadvantage that laser welding cannot be performed.

On the other hand, if the gap between the outer diameter of the cell and the inner diameter of the connection terminal C is too small, the periphery of the bottom of the connection terminal C is deformed downward when the cell is inserted into the connection terminal C formed of a cylindrical can. It happens. When the degree of this deformation increases, the peripheral portion of the bottom of the connection terminal C electrically connected to the negative electrode can 1 comes into contact with the positive electrode can 2 and short-circuits the cell B.

Further, the prior art for irradiating a laser from the side periphery of the connection terminals C, is to be laser irradiated
If the laser is irradiated without a stacked cell ,
There was a safety disadvantage that the workers nearby were directly irradiated. Furthermore, in the prior art, the laser welding of the cell B and the connection terminal C is performed in the vertical direction, and the laser welding of the cell A and the connection terminal C is performed in the horizontal direction. Had the disadvantage of becoming inconsistent.

The present invention solves the above-mentioned problems, and provides a laminated cell and a method of manufacturing the same that do not cause poor welding between the cell and the connection terminal and between the connection terminals and do not cause short-circuit of the cell due to deformation of the connection terminal. The purpose is to provide. Also,
An object of the present invention is to solve the above-mentioned problems and to provide a laminated cell to a worker by a safe manufacturing method.

Further, according to the present invention, the above-mentioned problems can be solved and all the welding portions 5a, 5b, 5c (see FIG. 1) can be welded by laser irradiation in the vertical direction. An object of the present invention is to provide a stacked cell and a method for manufacturing the stacked cell, which can be easily automated in mass production because it is not necessary to lay down or change the arrangement of the laser welding machine.

[0009]

In order to achieve the above object, a means adopted by the present invention is to interpose a connection terminal composed of two disks between cells. further,
The means adopted by the present invention is that the connection terminal B is provided on the negative electrode can of the cell B.
, A step of laser welding the connection terminal B and the negative electrode can, a step of arranging the connection terminal A on the positive electrode can of the cell A, a step of laser welding the connection terminal A and the positive electrode can, The stacked cell is manufactured by a manufacturing method including a step of stacking the cells A and B so that the connection terminals A and B are in contact with each other, and a step of laser-welding the outer periphery of the connection terminals A and B.

[0010]

In the laminated cell according to the first aspect, two connection terminals are interposed between the cells and the connection terminals are welded to each other, so that the cells are reliably electrically connected to each other. In this case, the connection terminals are also welded to the respective cells and are electrically connected. As described above, in order to weld the connection terminal and the connection terminal, there is an advantage that it is not necessary to tighten the dimensional accuracy and the gap accuracy between the cell and the connection terminal as compared with the welding of the cell and the connection terminal formed of the cylindrical can. .

According to the method for manufacturing a laminated cell according to the second aspect, the cell is not inserted into the connection terminal formed of the cylindrical can, so that the laminated cell can be produced without deforming the connection terminal. Further, since the overlapped connection terminals are laser-welded from above, laser welding is surely tried.

[0012]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a sectional view of a laminated cell showing one embodiment of the present invention,
FIGS. 2A and 2B are perspective views in which connection terminals are welded to cells. That is, FIG. 2A is a perspective view in which the connection terminal 3 is placed on the positive electrode can 2 of the cell A10 and then laser-welded at the welding location 5a.

FIG. 2B is a perspective view showing that the connection terminal 4 is placed on the negative electrode can 1 of the cell B20 and then laser-welded at a welding point 5b. In FIG. 1, a cell A10 is a laminated upper cell such as a button-type battery or a button-type electric double-layer capacitor, and a cell B20 is also a laminated lower-layer cell and is composed of a negative electrode can 1 and a positive electrode can 2, respectively.

Reference numeral 3 denotes a connection terminal A, which is laser-welded to the bottom of the positive electrode can 2 of the cell A at two or more welding points 5a.
Reference numeral 4 denotes a connection terminal B, which is laser-welded to the upper surface of the negative electrode can 1 of the cell B at two or more welding points 5b. The connection terminals 3 and 4 are made of SUS304 stainless steel having a thickness of 0.1 mm. When the connection terminals are discs, the outer diameter is 1 mm longer than the outer diameter of the battery.

After the connection terminals A and B are laser-welded to the cells A and B, respectively,
Are laminated so that the connection terminal A and the connection terminal B are in contact with each other. After the outer diameters of the connection terminals A and B are securely adjusted by an appropriate method, a laser 6 is applied to the outer periphery of the connection terminals 3 and 4 from the cell A side, that is, from above the connection terminals A and B. Welding is performed at the welding point 5C.

A method of irradiating a laser beam from the outer periphery of the connection terminals 3 and 4 for welding is also conceivable. However, if the connection terminals 3 and 4 are slightly warped, a gap is formed between the connection terminals 3 and 4. This is inconvenient because it causes welding defects. In addition, since guide jigs for adjusting the outer diameters of the connection terminals 3 and 4 are actually provided around the stacked cells, it is also difficult to irradiate the stacked cells with a laser beam in the lateral direction. In addition, in the case of laser irradiation from the lateral direction, if laser irradiation is performed in a state where there is no stacked cell, there is a possibility of direct irradiation to an operator, which is not desirable for safety.

After the stacked cell is assembled as described above,
Although not shown in the drawings, the laminated cell is covered with a heat-shrinkable tube except for the exposed portions of the negative electrode can 1 and the positive electrode can 2, and the lead terminals are laser-welded to the negative electrode can 1 and the positive electrode can 2, respectively, to obtain a final product. .

[0018]

As described above, according to the present invention, it is possible to provide a highly reliable laminated cell at a low cost by using the connection terminal having an extremely simple structure and eliminating the conventional disadvantage. Its industrial value is great.

[Brief description of the drawings]

FIG. 1 is a sectional view of a stacked cell according to an embodiment of the present invention.

FIGS. 2A and 2B are perspective views in which connection terminals are welded to cells A and B, respectively, according to an embodiment of the present invention.

FIG. 3 is a cross-sectional view of a conventional stacked cell.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Negative electrode can 2 Positive electrode can 3, 4, 7 Connection terminal 5a, 5b, 5c, 5d Welding point 6 Laser 10 Cell A 20 Cell B

Continuation of the front page (56) References JP-A-63-298961 (JP, A) JP-A-63-268219 (JP, A) JP-A-63-268222 (JP, A) JP-A-63-138661 (JP) JP-A-59-224056 (JP, A) JP-A-59-224055 (JP, A) JP-A-61-24957 (JP, U) JP-A-63-133064 (JP, U) (58) Field surveyed (Int.Cl. ⁶ , DB name) H01M 2/20

Claims (3)

(57) [Claims] 1. The outer diameter of the cell B on the negative electrode can of the cell B
It has a connection terminal B longer than the dimension, and is connected to the connection terminal B.
A connection terminal A, and a positive electrode can of the cell A on the connection terminal A.
And the connection terminal A is smaller than the outer diameter of the cell A.
A stacked cell characterized by a longer length . 2. Between the cell A and the connection terminal A,
Between the connection terminal A and the connection terminal B;
And a welded portion between the cell and the cell B.
Stacked cell. A step of arranging the connection terminal B on the negative electrode can of the cell B; a step of laser welding the connection terminal and the negative electrode can; a step of arranging the connection terminal A on the positive electrode can of the cell A; A step of laser welding the connection terminal and the positive electrode can, a step of laminating the cells A and B so that the connection terminals A and B are in contact with each other, and a step of laser welding the outer periphery of the connection terminals A and B. A method for producing a laminated cell.