JP4308591B2 - Manufacturing method of electric double layer capacitor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To easily secure an excellent joining state even in connecting a plurality of electric double layer capacitors and to easily deform a lead for positioning in an electrode structure comprising a container for sealing an electrode body together with an electrolytic solution and the lead pulled out from the electrode body to the outside of a case. <P>SOLUTION: While the lead 10 is constituted into the knitted body 11 of conductors, a resin seal part 12 for closing a gap between the knitted body 11 and the container and a resin filling part 13 for filling the mesh of the knitted body at a part corresponding to the seal part 12 are provided. <P>COPYRIGHT: (C)2005,JPO&amp;NCIPI

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for manufacturing an electric double layer capacitor. In particular, the present invention relates to a method of manufacturing an electric double layer capacitor according to an improvement of a terminal suitable for a lead drawn from a positive electrode body and a negative electrode body to the outside of a container .
[0002]
[Prior art]
2. Description of the Related Art In recent years, attention has been focused on application technologies of electric double layer capacitors that can be rapidly charged and have a long charge / discharge cycle life as various power storage devices (see Patent Documents 1 to 3).
[0003]
In FIG. 5, an example of the electric double layer capacitor will be described. 2 is a container for storing a capacitor main body (not shown) together with an electrolyte, 1 is a pair of terminals drawn out of the container 2 from the capacitor main body, Each terminal 1a, 1b is formed in a short shape from a metal (for example, aluminum) plate that is lightweight and has low electrical resistance, and is joined to the bundling portion of the corresponding lead portion inside the container 2.
[0004]
The capacitor body is composed of a positive electrode body, a negative electrode body, and a separator, and is composed of a laminate in which these are alternately stacked. The positive electrode body and the negative electrode body are composed of a collecting electrode and polarizable electrodes (activated carbon electrodes) formed on both surfaces thereof. These collector electrodes are made of a rectangular metal foil (for example, an aluminum foil), and a strip-shaped lead portion is formed integrally with one side of the rectangular plane. The lead portions of the collector electrode are bundled with the same polarity, and terminals 1a and 1b having polarities corresponding to the binding portions are joined.
[0005]
The capacitor body is immersed in the electrolytic solution and accommodated in the container 2. The container 2 is configured as a bag having one side opened from a resin laminated film (for example, aluminum laminate) having a metal intermediate layer, and a pair of terminals 1a and 1b (part of them) are formed from the opening. Drawn outside. The inside of the container 2 is vacuum-evacuated to remove excess electrolyte and air and moisture, and is sealed (heat-sealed) so that the opening of the bag sandwiches the pair of terminals 1a and 1b in a vacuum state. 2a is the heat welding part.
[0006]
As another example, an electrode structure that can be applied to an electric double layer capacitor is disclosed in which a surface treatment layer is formed on aluminum constituting a lead drawn from the electrode body to the outside of the container. (See Patent Document 4). A sealant layer is laminated on the surface treatment layer of aluminum, and the opening of the container is sealed (heat sealed) so as to sandwich this part.
[0007]
[Patent Document 1]
JP 2000-200740 [Patent Document 2]
Japanese Patent Laid-Open No. 11-87195 [Patent Document 3]
JP 07-94374 [Patent Document 4]
JP2000-155713A [0008]
[Problems to be solved by the invention]
In the example of FIG. 5, the pair of terminals 1 a and 1 b together with the lead portion of the collector electrode constitute a lead that is drawn out of the container 2 from the electrode body (positive electrode body and negative electrode body). For such a terminal 1, a good conductor such as aluminum is used in order to keep the internal resistance of the electric double layer capacitor small, and the thickness is set to be equal to or greater than the bundling portion of the lead portion. Since the pair of terminals 1 are thick and are not easily deformed, there is a problem that it is difficult to ensure a good bonding state even when a plurality of electric double layer capacitors are connected.
[0009]
An object of the present invention is to provide an effective means for solving such a problem.
[0010]
[Means for Solving the Problems]
In the first invention, a step of composing a laminated body in which these are alternately stacked from a positive electrode body, a negative electrode body, and a separator, a step of creating a terminal, and correspondence of polarity as a lead to each of the positive electrode body and the negative electrode body of the laminated body A step of bonding one end of the terminal to be opened, the container is formed in a container formed of a resin laminated film having a metal intermediate layer together with the electrolyte solution, and the other end of each terminal protrudes to the outside of the container. In the method of manufacturing an electric double layer capacitor comprising the step of sealing a part by heat sealing, the step of creating the pair of terminals includes a step of creating a knitted body of conductors as terminals, and a portion corresponding to the sealed portion of the container the step of creating a fill portion of the resin to fill the meshes of knitting, the step of creating a seal portion of the resin for closing the gap between the container to the outer shape of the knitting of the portion corresponding to the sealing portion of the container, in that it comprises And butterflies.
[0011]
According to a second aspect of the present invention, in the method for manufacturing an electric double layer capacitor according to the first aspect , the terminal is formed in a knitted body of thin aluminum wires .
[0012]
According to a third aspect of the present invention, in the method for manufacturing the electric double layer capacitor according to the first or second aspect of the invention, the outer shape of the knitted body of the terminal is made short .
[0013]
According to a fourth aspect of the present invention, in the method for manufacturing the electric double layer capacitor according to any one of the first to third aspects, a resin filling portion that fills the mesh of the knitted body, and the knitted body and the container, The resin seal portion for closing the gap is made of PP material .
[0017]
【The invention's effect】
In 1st invention-4th invention, the sheet | seat part of a knitted body is heat-welded to the inner layer (resin) of a container by the sealing (heat seal) process of a container, and the clearance gap between a knitted body and a container is sealed. . By the filling portion that fills the mesh of the knitted body, the sealing performance of the container is ensured, and leakage of the electrolyte from the knitted body is also prevented .
[0018]
The filling portion is not limited to the entire terminal (the knitted body of the conductor), but is limited to the local portion that covers the sealing portion (thermal welding portion) of the container. The inner portion and the outer portion of the container that sandwich the portion are flexible. Since it remains in the deformable knitted state, it is easy to bend it for alignment, and it is easy to ensure a good connection (joining) state of the terminals. Electricity has the property of intensively flowing on the surface of the conductor, and by forming the conductor in a knitted body, the surface area can be efficiently obtained, so that the electrical conductivity of the terminal is also increased .
[0019]
Even in the case where the sheet portion and the filling portion are different resins, heat sealing between the sealing portion and the filling portion and heat welding between the sheet portion and the inner layer (resin) of the container are obtained by heat sealing. Good coupling (integration) can be realized .
[0020]
In the second invention , by forming the knitted body of a thin aluminum wire, a terminal suitable for a lead having a light weight and high conductivity can be obtained .
[0021]
In the third invention , because of the short shape, the knitted body is easy to bend, and the knitted bodies can be easily joined by overlapping them .
[0022]
In the fourth aspect of the invention , the PP (polypropylene) material of the sheet portion is thermally welded to the container and fused with the PP material of the filling portion by heat sealing, so that the bonding strength between the container and the knitted body is also improved.
[0024]
DETAILED DESCRIPTION OF THE INVENTION
In FIG. 1, reference numeral 10 denotes a pair of terminals drawn out from the capacitor body 30 to the outside of the container 20 (a part of which is indicated by a two-dot chain line). Joined (welded) to the bundling portion.
[0025]
The capacitor body 30 is composed of a positive electrode body, a negative electrode body, and a separator, and is composed of a laminated body in which these are alternately stacked. The positive electrode body and the negative electrode body are composed of a collecting electrode and polarizable electrodes (activated carbon electrodes) formed on both surfaces thereof. These collector electrodes are made of a rectangular metal foil (for example, an aluminum foil), and a strip-shaped lead portion 31 is formed integrally with one side of the rectangular plane. The lead portions 31a and 31b of the collector electrode are bundled with the same polarity, and the terminals 10a and 10b having polarities corresponding to these binding portions are joined as shown in FIG. Reference numerals 32a and 32b are joint portions due to welding of the terminals 10a and 10b and the lead portions 31a and 31b (each bundling portion).
[0026]
The capacitor body 30 is immersed in the electrolytic solution and accommodated in the container 20. The container 20 is configured in a bag shape having one side opened from a resin laminated film (for example, aluminum laminate) having a metal intermediate layer, and a pair of terminals 10a and 10b (part of these) are containers from the opening. 20 is pulled out. The inside of the container 20 is vacuum-evacuated to remove air and moisture together with excess electrolyte solution, and the bag opening is sealed (heat sealed) so that the opening of the bag sandwiches the pair of terminals 10a and 10b. 20a is the heat welding part.
[0027]
The pair of terminals 10a, 10b is made by cutting the knitted fabric into a short shape. The fabric is knitted into a mesh structure in which meshes are layered from a lightweight and highly conductive material (thin aluminum wire). As clearly shown in FIGS. 3 and 4, the short knitted body 11 includes a resin seal portion 12 that closes a gap between the container 20 and a resin filling portion 13 that fills a mesh of a portion corresponding to the seal portion 12. Are provided. The seal part 12 and the filling part 13 are integrally formed of the same heat-weldable resin (for example, PP material). 10A is an aluminum wire that hits the warp yarn of the knitted body, and illustration of the aluminum wire that hits the weft yarn is omitted.
[0028]
The sheet portion 12 integrated with the filling portion 13 is thermally welded to the inner layer (resin) of the bag by a sealing (heat sealing) process of the container 20 to seal the gap between the knitted body 11 and the container 20. The filling portion 13 that fills the mesh of the knitted body 11 ensures the sealing performance of the container 20 and prevents leakage of the electrolyte from the knitted body 11.
[0029]
The filling portion 13 is not limited to the entirety of the terminal 10 (knitted body 11) but is limited to a local portion that covers the sealing portion (thermal welding portion 20a) of the container 20, and the inner portion and the outer portion of the container 20 sandwiching the portion 20a. Since the mesh is left in a knitted state that can be flexibly deformed, even when a plurality of electric double layer capacitors are connected in series or in parallel, it is easy to bend the terminal 10 for alignment, It is easy to ensure a joined state.
[0030]
The knitted body 11 has a conductor surface area that is more efficient than a conventional thick plate. Therefore, the knitted body 11 together with the lead part 31 of the collector electrode constitutes a lead that is led out of the container 20 from the electrode body (positive electrode body and negative electrode body). 10 is increased, and the internal resistance of the electric double layer capacitor is also kept small.
[0031]
Since the sheet portion 12 that is heat-welded to the inner layer of the container 20 is integrated with the filling portion 13 that fills the mesh of the knitted body 11, it is difficult to peel off from the knitted body 11, and the knitted body 11 and the container 20 have good bonding strength. can get. It is also conceivable to form the filling portion 13 and the sheet portion 12 separately using different resins. In that case, the sheet portion 12 is assembled to the filling portion 13 of the knitted body 11 and thermally welded to the inner layer of the container 20 and the surface of the filling portion 13 filling the mesh of the knitted body 11 by a bag sealing (heat sealing) process. It is.
[0032]
The electrode structure including the flexible deformable knitted body 11 is not limited to application to an electric double layer capacitor, and can be widely used for various electric devices including other power storage devices. Become.
[Brief description of the drawings]
FIG. 1 is a partial configuration explanatory view of an electric double layer capacitor according to an embodiment of the present invention.
FIG. 2 is an explanatory diagram of the configuration related to the main part.
FIG. 3 is an explanatory diagram of the configuration of terminals similarly;
FIG. 4 is an explanatory view of the configuration of terminals similarly.
FIG. 5 is an external view of an electric double layer capacitor.
[Explanation of symbols]
10 (10a, 10b) Terminal 11 Knitted body 12 Sealing part 13 Filling part 20 Container 20a Sealing part (thermal welding part)
30 Capacitor body 31 (31a, 31b) Lead portion of collector electrode

Claims (4)

A step of composing a laminated body in which a positive electrode body, a negative electrode body, and a separator are alternately stacked, a step of creating a terminal, and joining one end of a terminal corresponding to polarity to each of the positive electrode body and the negative electrode body of the laminated body A step of sealing the opening of the container with a heat seal so that the other end of each terminal protrudes to the outside of the container in a container formed of a laminated film of resin having a metal intermediate layer together with the electrolyte In the method of manufacturing the electric double layer capacitor, the step of creating the terminal includes the step of creating a knitted body of the conductor as the terminal, a resin filling the mesh of the knitted body of the portion corresponding to the sealing portion of the container An electric double layer comprising: a step of creating a filling portion; and a step of creating a resin seal portion that closes a gap between the container and the outer shape of the knitted body corresponding to the sealing portion of the container Method of manufacturing a Yapashita. 2. The method for manufacturing an electric double layer capacitor according to claim 1, wherein the terminal is formed in a knitted body of a thin aluminum wire . The method for manufacturing an electric double layer capacitor according to claim 1, wherein the outer shape of the knitted body is created in a short shape for the terminal . 4. The resin filling portion that fills the mesh of the knitted body and the resin sealing portion that closes the gap between the knitted body and the container are made of PP material. A method of manufacturing an electric double layer capacitor according to claim 1 .

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