JP2003124078A - Electric double layer capacitor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve manufacturability of an electric double layer capacitor. SOLUTION: The electric double layer capacitor comprises a laminate 10, and a container 20 made of a laminating film having an intermediate layer of a metal between resin films in a state in which terminals 13a, 13b externally protrude. The container 20 is formed in a divided structure of a receiving case 21 and a cover 22 having recesses 23, 26 of a predetermined depth corresponding to the laminating thickness of the laminate 10, flanges 24, 27 are respectively provided on the peripheries of the case 21 and the cover 22, and the flanges 24, 27 are sealed by heat-sealing.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to an electric double layer capacitor.

[0002]

2. Description of the Related Art In recent years, as a variety of power storage devices (driving power sources for electric vehicles, etc.), attention has been paid to the application technology of electric double layer capacitors, which can be rapidly charged and have a long charge / discharge cycle life.

An electric double layer capacitor is constructed by alternately stacking a certain number of positive electrode bodies and negative electrode bodies with a separator interposed therebetween. These laminates are dipped in an electrolytic solution and housed in a container (Japanese Patent Laid-Open No. 2000-200738).
No. 11-274014).

[0004]

FIG. 7 illustrates an example of an electric double layer capacitor, in which 1 is a container for accommodating a capacitor body (not shown) together with an electrolytic solution, and 2 is an outside of the container 1. A pair of terminal plates that are pulled out (aluminum electrodes)
Each of the terminal plates 2a and 2b is bonded inside the container 1 to the multi-layered portion of the lead portion of the corresponding polarity.

In the capacitor body, the collector electrodes of the positive electrode body and the negative electrode body are formed of aluminum foil, and an activated carbon electrode (polarizable electrode) is formed on one surface thereof. The lead portions are formed on these collector electrodes, and the terminal plate 2 is joined to the multi-layer portion that collects these same poles. For joining with the terminal plate 2, ultrasonic welding, spot welding, or the like is used so as to ensure good electrical conductivity and not damage the lead portion of the aluminum foil.

The inside of the container 1 is sealed in a vacuum while the main body of the capacitor is stored, immersed in an electrolytic solution, and excess electrolytic solution is extracted. The electric double layer capacitor as a product is
When applied to the drive power source of an electric vehicle, many are connected in series / parallel (for example, in series connection, the terminal boards 2a and 2b are connected).
The different polarities are sequentially joined) to form an assembled battery of the required capacity.

In such an electric double layer capacitor, while the pair of terminal plates 2a and 2b are drawn out to the outside, the capacitor body must be shielded from the outside air. Therefore, it is conceivable that the container 1 is formed into a bag shape with a laminated film having a laminated structure (for example, aluminum laminate) including a resin film and a metal intermediate layer, and sealed by heat sealing or the like.

However, it is difficult to put such a capacitor body in the bag-shaped container 1. Since the container 1 has a size with almost no gap with respect to the capacitor main body, it is difficult to insert the capacitor main body, and there is a possibility that the laminated collector electrode, activated carbon electrode, and separator are displaced when being inserted. In addition, in the bag-shaped container 1, the insertion port needs to be widened in accordance with the capacitor body.

Therefore, there is a problem that manual work is difficult, workability is poor, and automation is not easy.

There is a method in which the capacitor body is wrapped in a resin sheet or the like, and the whole is heated to a high temperature for a predetermined time and laminated (see Japanese Patent No. 3005992). However, if the whole is heated in this way, the number of steps is reduced. This will increase the production cost.

The present invention solves these problems,
An object is to provide an electric double layer capacitor having excellent manufacturability.

[0012]

According to a first aspect of the present invention, a certain number of positive electrode bodies and negative electrode bodies are alternately laminated with a separator interposed therebetween, and each positive electrode body and a part of each negative electrode body are leaded. Join the multi-layered parts of the same pole to the terminals as parts,
In an electric double layer capacitor obtained by accommodating these laminated bodies in a container made of a laminated film having a metal intermediate layer between resin films in a state where terminals are projected to the outside, the container is laminated with the laminated body. It is formed as a divided structure of a receiving case and a cover, each of which has a recess with a predetermined depth corresponding to the thickness, and flanges are provided around the receiving case and around the cover, and these flanges are heat-sealed. Sealed by.

According to a second aspect of the present invention, a certain number of positive electrode bodies and negative electrode bodies are alternately laminated with a separator interposed therebetween, and a part of each positive electrode body and each negative electrode body is used as a lead portion to connect the same poles. In an electric double layer capacitor formed by joining the multi-layered portion to each terminal and accommodating these laminated bodies in a container made of a laminated film having a metal intermediate layer between resin films in a state where the terminals are projected to the outside, The container is formed in a divided structure of a receiving case having a recess having a depth substantially equal to the laminated thickness of the laminated body and a flat cover, and flange portions are provided around the receiving case and around the cover. , These flanges are sealed by heat sealing.

According to a third aspect of the present invention, in the first and second aspects of the present invention, the terminal is projected outside from between the flange portion of the receiving case and the flange portion of the cover, and the terminal and the flange portion of the receiving case are formed. A welding agent for heat sealing is interposed between the terminals and between the terminals and the flange portion of the cover for sealing.

[0015]

According to the first and second aspects of the present invention, the capacitor body can be easily housed in the container made of the laminated film, and the container can be easily sealed by heat sealing. Therefore,
The workability is good, and it is possible to construct a process extremely easily when not only a manual work but also a robot or other machine is operated, automation can be easily performed, and cost reduction can be achieved.

According to the third invention, it is possible to reliably seal between the terminal and the flange portion of the receiving case and between the terminal and the flange portion of the cover.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is an exploded perspective view of the electric double layer capacitor of the first embodiment, 10 is a capacitor body (laminate), 20 is a container formed in a divided structure of a receiving case 21 and a cover 22. Is.

The capacitor body 10 is formed by alternately stacking a certain number of positive electrode bodies and negative electrode bodies with a separator interposed therebetween. As shown in FIG. 2, the collector electrode 11a of the positive electrode body and the collector electrode 11b of the negative electrode body are formed by stamping an aluminum foil, and a pair of activated carbon electrodes and a separator are interposed between the collector electrodes 11a and 11b. To be dressed.

Lead portions 12a, 1 are provided on one side of one side of the rectangular plane of the collector electrode 11a of the positive electrode body and the collector electrode 11b of the negative electrode body.
2b is provided, and the lead portions 12a and 12b having the same polarity are provided.
The terminal plates 13a and 13b (aluminum electrodes) of the polarities corresponding to the multi-layer portion of are joined. The terminal plates 13a, 13b and the lead portions 12a, 12b are joined by ultrasonic welding, spot welding or the like so as to ensure good electrical conductivity and not damage the lead portions 12a, 12b of the aluminum foil. .

The receiving case 21 and the cover 2 of the container 20
2 has a metal intermediate layer (aluminum layer) between resin films.
A laminated film (for example, an aluminum laminated sheet composed of a polyethylene layer, a nylon layer, an aluminum layer, a nylon layer, etc.) is used.

The receiving case 21 is provided with a concave portion 23 having a predetermined depth so as to cover the capacitor body 10 from one laminated surface side, and a flange portion 24 is formed around the concave portion 23.

The wall surface 25 of the concave portion 23 on the side of the terminal plates 13a, 13b is formed into a curved surface so as to match the lead portions 12a, 12b, and the flange portion 24 on the side of the terminal plates 13a, 13b has a part of the terminal plates 13a, 13b outside. It is formed in a size that protrudes into.

The cover 22 is provided with a concave portion 26 having a predetermined depth so as to cover the capacitor body 10 from the opposite side of the case 21, and a flange portion 27 is formed around the concave portion 26.

A wall surface 28 of the recess 26 on the side of the terminal plates 13a, 13b is formed into a curved surface so as to fit the lead portions 12a, 12b, and a flange portion 27 on the side of the terminal plates 13a, 13b has a part of the terminal plates 13a, 13b outside. It is formed in a size that protrudes into.

The depth of the recessed portion 23 of the receiving case 21 and the depth of the recessed portion 26 of the cover 22 are formed such that the sum of these is approximately equal to the laminated thickness of the laminated portion 15 of the capacitor body 10.

In this case, for example, the recess 2 of the receiving case 21
The depth of 3 and the depth of the recess 26 of the cover 22 are formed to be approximately 1/2 of the laminated thickness of the laminated portion 15 of the capacitor body 10.

When the depth of the concave portion 23 of the receiving case 21 is X% of the laminated thickness of the laminated portion 15 of the capacitor body 10, the depth of the concave portion 26 of the cover 22 corresponds to the laminated portion 15 of the capacitor body 10. It may be (100-X)% of the laminated thickness.

Then, as shown in (a) to (c) of FIG.
The laminated portion 15 of the capacitor body 10 is placed in the recess 23 of the receiving case 21, and the cover 22 is placed over the laminated portion 15 to set it.

In this case, the laminated portion 15 of the capacitor body 10 is immersed in the electrolytic solution in advance. In addition, the terminal boards 13a, 1
A welding agent for heat sealing is applied to 3b in order to compensate the fusion property of the receiving case 21 and the cover 22 with the laminated film. A PE (polyethylene) material containing an adhesive is used as the welding agent.

Next, in this set state, the receiving case 21 and the flange portions 24 and 27 of the cover 22 are sealed by heat sealing while the inside of the container 20 is evacuated.

By heat sealing, the terminal boards 13a, 13b
This welding agent melts and the flange portions 24 and 27 of the receiving case 21 and the cover 22 are surely welded to the terminal plates 13a and 13b, and the mating surfaces of the flange portions 24 and 27 are surely welded.

The sectional structure of the electric double layer capacitor thus manufactured is shown in FIGS. 4 (a) and 4 (b).

As described above, the container 20 for accommodating the capacitor body 10 is constituted by the receiving case 21 and the cover 22 which are divided in the stacking direction of the capacitor body 10, and
Since the flanges 24 and 27 are sealed by heat sealing, they are easy to manufacture.

When the capacitor body 10 is housed in the container 20, the laminated portion 15 of the capacitor body 10 is received in the case 2.
It is only necessary to place it in the concave portion 23 of No. 1 and cover it with the cover 22. The laminated collector electrodes 11a and 11b, the activated carbon electrode, and the separator are not displaced and can be easily accommodated in the container 20. Moreover, it can be easily sealed by heat sealing.

Therefore, the workability is excellent, and the process can be extremely easily set up not only in the manual work but also in the case where the robot or other machine is operated. As a result, the automation can be facilitated and the cost can be reduced. .

On the other hand, since the concave portion 23 of the receiving case 21 and the concave portion 26 of the cover 22 are shallow drawn, molding is easy.

When the depth of the recessed portion 23 of the receiving case 21 and the depth of the recessed portion 26 of the cover 22 are set to be the same (approximately 1 of the laminated thickness of the laminated portion 15 of the capacitor body 10).
In the case of / 2), the receiving case 21 and the cover 22 are made to be a common part, so that the number of parts can be reduced and the cost can be further reduced.

FIG. 5 and FIG. 6 show the second embodiment.
In this, the depth of the recess 32 of the container 30 receiving case 31 is formed to be substantially equal to the laminated thickness of the laminated portion 15 of the capacitor body 10, while the cover 33 is formed in a flat plate shape.

Even in this case, the production can be easily performed, good workability can be secured, and the cost can be reduced.

[Brief description of drawings]

FIG. 1 is an exploded configuration diagram showing a first embodiment.

FIG. 2 is an explanatory diagram of a configuration of a capacitor body.

FIG. 3 is an explanatory diagram of a manufacturing process.

FIG. 4 is a sectional view of the present capacitor.

FIG. 5 is a sectional view showing a second embodiment.

FIG. 6 is an explanatory diagram of a manufacturing process.

FIG. 7 is an explanatory diagram of background art.

[Explanation of symbols]

10 Capacitor body 13a, 13b terminal board 20 containers 21 receiving case 22 cover 23 recess 24 Flange 26 recess 27 Flange 30 containers 31 receiving case 32 recess 33 cover

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Shuichi Araki             Saitama Prefecture Ageo City Oita Ichome Ichibanchi Nissan Di             Within Hazel Industry Co., Ltd.

Claims (3)

[Claims] 1. A certain number of positive electrode bodies and negative electrode bodies are alternately laminated with a separator interposed therebetween, and a part of each positive electrode body and each negative electrode body is used as a lead portion to form a multi-layer portion of the same poles. An electric double layer capacitor, which is joined to a terminal and is housed in a container made of a laminated film having a metal intermediate layer between resin films in a state where these laminated bodies are projected to the outside, wherein the container is It is formed in a divided structure of a receiving case and a cover each having a recess of a predetermined depth corresponding to the laminated thickness of the laminated body, and flange portions are provided around the receiving case and the cover, respectively. An electric double layer capacitor characterized in that a flange portion is sealed by heat sealing. 2. A certain number of positive electrode bodies and negative electrode bodies are alternately laminated with a separator interposed therebetween, and a part of each positive electrode body and each negative electrode body is used as a lead portion to form a multi-layer portion of the same poles. An electric double layer capacitor, which is joined to a terminal and is housed in a container made of a laminated film having a metal intermediate layer between resin films in a state where these laminated bodies are projected to the outside, wherein the container is It is formed in a divided structure of a receiving case having a recess having a depth approximately equal to the laminated thickness of the laminated body and a flat plate-like cover, and flange portions are provided around the receiving case and around the cover. An electric double layer capacitor, characterized in that the portion is sealed by heat sealing. 3. The terminal is projected outside from between a flange portion of a case and a flange portion of a cover, and
3. The electric double layer according to claim 1, wherein a sealing agent is interposed between the terminal and the flange portion of the receiving case and between the terminal and the flange portion of the cover for sealing. Capacitors.