JP2008124089A - Aluminum lamination package structure for electric double-layer capacitor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a highly reliable aluminum lamination package structure for electric double-layer capacitor that is resistive to storage for a longer period. <P>SOLUTION: In the aluminum lamination package structure for electric double-layer capacitor, an electric double-layer capacitor 1 is packaged with lamination films 2, 3 constituted with at least aluminum foils 21, 31, protection films 22, 31 provided to one surfaces of the aluminum foils 21, 31 and fused films 23, 33 provided to the other surfaces of the aluminum foils 21, 31, openings of the lamination films 2, 3 are fused for hermetic seal, and an aluminum foil protection film 4 is provided, for shielding contact between the aluminum foils 21, 31 and external air, to the end surface of the fusing portions of the lamination films 2, 3. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an aluminum laminate packaging structure for an electric double layer capacitor using a laminate film.

  At present, packaging using a laminate film is used in various fields. For example, retort pouches for foods, packaging for electronic components that do not like humidity, and recently, lithium batteries, electric double layer capacitors (for example, Patent Document 1). Used widely).

  As described above, the reason why the packaging using the laminate film is widely used includes that the laminate film has excellent gas barrier properties, and that the polymer film to be laminated has excellent heat weldability. . Packaging with a laminate film enables simple packaging, ensures sealing performance, and enables cost reduction.

JP 2006-24660 A

  FIG. 2 schematically shows an example of a conventional aluminum laminate packaging structure for an electric double layer capacitor. As shown in FIG. 2, in the conventional aluminum laminate packaging structure for an electric double layer capacitor, the electric double layer capacitor 1 is disposed between two laminate films 2 and 3 having the same shape, for example, and the peripheral edges of the laminate films 2 and 3 are arranged. Are performed by welding each other. In addition, the electric double layer capacitor 1 and the laminate films 2 and 3 shown in FIG. 2 are exaggerated for convenience of explanation, unlike the actual dimensional ratio.

  Laminate films 2 and 3 are three layers in which protective film layers 22 and 32 as protective films are arranged on at least one surface of aluminum foils 21 and 31 and welding films 23 and 33 as welding films are arranged on the other surface. The electric double layer capacitor 1 is covered by covering the electric double layer capacitor 1 so that the welding films 23 and 33 are opposed to each other, and heat-sealing and sealing the peripheral portion.

  Thus, by packaging the electric double layer capacitor 1 with the laminate films 2 and 3, the volume and weight of the capacitor unit can be reduced.

  Furthermore, in the electric double layer capacitor 1, it is desirable to maintain the environment such as gas components in the unit, that is, in the laminate films 2 and 3 covering the electric double layer capacitor 1, as much as possible at the time of manufacture. If the capacitor 1 is packaged by the laminate films 2 and 3, the cell is completely shielded from the outside air by the gas barrier effect of the aluminum foils 21 and 31, and the environment in the unit (inside the aluminum laminate package), that is, the reduced pressure state. It is possible to maintain the gas components and the like in the initial manufacturing state over a long period of time.

  However, according to the conventional aluminum laminated packaging structure for an electric double layer capacitor shown in FIG. 2, the gas permeation and moisture absorption through the protective films 23 and 33 can be blocked, but the laminated films 2 and 3 The aluminum foils 21 and 31 are exposed and exposed to the atmosphere at the welding cross section, that is, at the end face of the peripheral edge where the laminate films 2 and 3 are welded.

  When the electric double layer capacitor 1 that has been laminated in such a state is placed in an environment such as long-term storage, high humidity, or corrosive atmosphere, the aluminum foils 21 and 31 are corroded from the end surfaces exposed to the atmosphere. There is a possibility that.

  When the aluminum foils 21 and 31 are corroded and the corrosion gradually progresses into the laminated films 2 and 3, the aluminum foils 21 and 31, the protective films 22 and 32, and the welding films 23 and 33 are peeled off from each other, and the laminated films 2 and 3 There is a risk that the gas may permeate from the surfaces of the welding films 23 and 33 into the space sealed by.

  In particular, electrochemical reaction cells such as batteries and capacitors are greatly affected by moisture and oxygen. For example, when moisture enters the unit in the electric double layer capacitor 1, gas is generated due to the influence of the moisture, and a force that pushes the gap between the cells by the gas pressure of the generated gas acts to cause contact resistance of the electrodes. May increase. Therefore, in the aluminum laminate packaging of the electric double layer capacitor, it is necessary to prevent peeling between the aluminum foils 21 and 31, the protective films 22 and 32, and the welding films 23 and 33.

  An object of the present invention is to solve such problems, and to provide an aluminum laminate packaging structure for an electric double layer capacitor that is more reliable and can withstand long-term storage.

  An aluminum laminate packaging structure for an electric double layer capacitor according to a first invention for solving the above-described problem is provided with at least an aluminum foil, a protective film provided on one surface of the aluminum foil, and the other of the aluminum foil. In an aluminum laminate packaging structure for an electric double layer capacitor, wherein the electric double layer capacitor is enclosed by a laminate film composed of a welding film provided on the surface, and the opening of the laminate film is welded and sealed, the welding of the laminate film An aluminum foil protection means for blocking contact between the aluminum foil and outside air is provided on the end face of the part.

  In the aluminum laminated packaging structure for an electric double layer capacitor according to the second invention for solving the above-mentioned problems, the aluminum foil protecting means covers the welded portion of the laminate film and is adhered to the welded portion, It is characterized by comprising an aluminum foil protective film that blocks the contact between the foil and the outside air.

  According to the aluminum laminate packaging structure for an electric double layer capacitor according to the present invention described above, the aluminum foil is exposed at the end face of the welded portion of the laminate film for packaging the electric double layer capacitor by providing the aluminum foil protection means. This can prevent the aluminum foil from corroding. Thereby, the structure of a laminate film can be maintained over a long period of time.

  Furthermore, since the layers constituting the laminate film are not peeled off from each other and the gas barrier property of the laminate film can be maintained over a long period of time, the environment in the package in which the electric double layer capacitor is packaged is more than that in the past. It becomes possible to maintain the state at the time of manufacture, and the quality of the electric double layer capacitor can be maintained in a stable state over a longer period than before. As a result, the aluminum laminate packaging structure for electric double layer capacitors can be made more reliable and can withstand long-term storage.

  One embodiment of the present invention is shown below. The aluminum laminate packaging structure for an electric double layer capacitor according to this embodiment is a laminate composed of at least an aluminum foil, a protective film provided on one surface of the aluminum foil, and a welding film provided on the other surface of the aluminum foil. The electric double layer capacitor is enclosed by a film, the opening of the laminate film is welded and sealed, and the electric double layer capacitor is held under reduced pressure.

  Furthermore, in order to prevent the aluminum foil exposed at the end face of the welded portion, which is the portion where the opening of the laminate film is welded, from being in contact with the atmosphere, for example, it is possible to adhere to the laminate film and block the gas flow. Aluminum foil protection means such as covering the end face of the welded portion of the laminate film with a film made of a possible polymer material is provided.

  According to the present embodiment, since the aluminum foil is not exposed to the atmosphere, there is no risk of the aluminum foil being eroded, and the electric double layer capacitor is maintained in the environment during manufacturing for a long time, and stable quality is achieved. Can be maintained.

  An embodiment of an aluminum laminate packaging structure for an electric double layer capacitor according to the present embodiment will be described in detail with reference to the drawings. FIG. 1 is a cross-sectional view schematically showing a state in which the electric double layer capacitor in this embodiment is packaged with a laminate film.

  This embodiment is a structure in which an aluminum foil protective film 4 is added to the above-described conventional aluminum laminated packaging structure for an electric double layer capacitor, and hereinafter, the same members as those shown in FIG. A duplicate description will be omitted. As in FIG. 2, the laminate films 2 and 3 are also exaggerated in FIG.

  As shown in FIG. 1, an aluminum foil protective film 4 as an aluminum foil protective means is provided on the peripheral surfaces of the laminated films 2 and 3 that cover the electric double layer capacitor 1 and are welded to each other in this embodiment. Is provided. That is, the portions of the laminate films 2 and 3 where the aluminum foils 21 and 31 are exposed are covered with the aluminum foil protective film 4 so that the aluminum foils 21 and 31 are not in direct contact with the outside air.

  The aluminum foil protective film 4 is made of a polymer material that can be bonded to at least the protective films 22 and 32. For example, the laminated films 2 and 3 and the aluminum foil protective film are inserted in a state where the welded portions of the laminate films 2 and 3 are inserted into the openings of the aluminum foil protective film 4 folded in half and the welded portions are sandwiched by the aluminum foil protective film 4. By adhering 4, the contact between the aluminum foils 21 and 31 and the outside air can be blocked.

  According to the present embodiment, the above-described configuration prevents the aluminum foils 21 and 31 exposed at the end faces of the laminate films 2 and 3 from being exposed to the atmosphere, thereby preventing the aluminum foils 21 and 31 from being corroded. The shape of the laminate films 2 and 3 can be maintained over a long period of time. Accordingly, the laminate portions of the laminate films 2 and 3 are not peeled off, and the gas barrier properties of the laminate films 2 and 3 can be maintained over a long period of time. As a result, the electric double layer capacitor 1 sealed with the laminate films 2 and 3 can maintain stable quality over a long period of time.

  In FIG. 1, a gap is provided between the welded portions of the laminate films 2 and 3 and the aluminum foil protective film 4, but the welded portions of the laminate films 2 and 3 and the aluminum foil protective film 4 Needless to say, these may be in close contact with each other, and various modifications can be made without departing from the gist of the present invention.

  The present invention is applicable to an aluminum laminate packaging structure for an electric double layer capacitor that maintains an electrochemical reaction cell such as a battery or a capacitor in a sealed state.

It is sectional drawing which shows typically the aluminum laminate packaging structure for electric double layer capacitors which concerns on the Example of this invention. It is sectional drawing which shows typically the conventional aluminum laminated packaging structure for electric double layer capacitors.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Electric double layer capacitor 2, 3 Laminate film 21, 31 Aluminum foil 22, 32 Protective film 23, 33 Welding film 4 Aluminum foil protective film

Claims (2)

  An electric double layer capacitor is contained by a laminate film composed of at least an aluminum foil, a protective film provided on one surface of the aluminum foil, and a welding film provided on the other surface of the aluminum foil, and the laminate film In the aluminum laminate packaging structure for an electric double layer capacitor, in which the opening is welded and sealed, an aluminum foil protection means for blocking contact between the aluminum foil and the outside air is provided on the end face of the welded portion of the laminate film. Aluminum laminated packaging structure for electric double layer capacitors.   The said aluminum foil protection means consists of an aluminum foil protective film which covers the welding part of the said laminate film, is adhere | attached on the said laminate film, and interrupts | blocks the contact of the said aluminum foil and external air. Aluminum laminated packaging structure for electric double layer capacitors.

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