JP2001148234A - Electrochemical device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electrochemical device that is superior in sealing property and superior in anti-leakage of liquid, and provide its manufacturing method. SOLUTION: This is an electrochemical device having a sheathing body and an electrochemical element enclosed in this body, and above sheathing body is a laminate positive layer having metal layer and heat-adhesive resin layer, and above electrochemical device is tight sealed at the seal portion where heat-adhesive resin layer of above sheathing body is mutually heat bonded, and has outlet terminals that lead to outside through above seal portion, and one of these outlet terminals is made as the electrochemical device in which at least the part corresponding to above seal portion is rough-surfaced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrochemical device such as a polymer lithium secondary battery and an electric double layer capacitor, and a method of manufacturing the same. It relates to a manufacturing method.

[0002]

2. Description of the Related Art In recent years, carbon materials, tin oxide, silicon oxide and the like have been used as negative electrode active materials called lithium secondary batteries.
Secondary batteries are used or considered for various electronic products and electric vehicles. These lithium secondary batteries are
A so-called electrolyte solution in which an electrolyte salt is dissolved in a liquid solvent is used. Batteries using an electrolytic solution have the advantage of low internal resistance, but, on the other hand, have the problem of liability to leak and ignition. To address such problems, for example, a gel polymer solid electrolyte comprising a polymer, an electrolyte salt and a solvent has recently been spotlighted.

[0003] Such a gel-like polymer solid electrolyte is
In some cases, the conductivity is close to that of a liquid and shows a value on the order of 10 ⁻³ S · cm ⁻¹ .

A battery using a solid polymer electrolyte does not leak easily because it does not use a liquid electrolyte. Therefore,
Unlike a conventional battery using a liquid electrolyte, it is not necessary to mechanically caulk with a metal container and a polymer packing in question. In a battery using a polymer solid electrolyte, liquid leakage can be prevented only by using a laminate film composed of a polymer film and a metal foil as an outer package (container).

However, the adhesion between the lead terminal (metal foil) extending from the inside of the battery to the outside and the polymer film (thermally adhesive resin layer) on the innermost surface of the laminate film is insufficient, and the sealing property of the battery is poor. However, this is not sufficient, and this has been a problem in terms of the cycle life of the battery.

In order to improve the above-mentioned drawbacks, Japanese Patent Application Laid-Open
No. 2,896,989 discloses a thin sealed battery in which a power generation element containing both positive and negative electrodes and an electrolyte is housed in an outer package composed of a laminate sheet in which a heat-fusible resin layer is fixed to both surfaces of a metal layer. A current collecting tab made of metal is provided on each of the positive and negative electrodes, and each of the current collecting tabs is led out of the battery from a terminal lead-out part of the exterior body, and the terminal lead-out part has a terminal and an exterior body surface. A thin sealed battery characterized by being sealed by heat-sealing with a heat-sealing modified resin layer interposed is disclosed.

However, the above-mentioned heat-fused modified resin layer has a disadvantage that the sealing property is still insufficient.
Analysis of this cause revealed that the adhesion between the terminal (metal) and the modified resin layer was reduced by the lithium salt-containing organic electrolyte, but the electrolyte did not touch the terminal seal at the time of injection. It was very difficult to make batteries.

[0008]

SUMMARY OF THE INVENTION An object of the present invention is to provide an electrochemical device having excellent sealing properties and excellent liquid leakage resistance.

[0009]

This and other objects are attained by the present invention described below. (1) An electrochemical device having an exterior body and an electrochemical element enclosed in the exterior body, wherein the exterior body is a laminate film having a metal layer and a heat-adhesive resin layer. The chemical device has a lead-out terminal that is sealed and sealed by a heat-sealed seal portion between the heat-adhesive resin layers of the exterior body, and leads to the outside through the seal portion. Is an electrochemical device in which at least a portion corresponding to the seal portion is roughened. (2) The lead terminal has a surface roughness Ra = 0.06-
The electrochemical device according to the above (1), which is roughened to a roughness of 0.20 μm. (3) The electrochemical device according to (1) or (2), wherein the heat-adhesive resin layer of the laminate film is a polypropylene resin. (4) The above (1) to (3) having an acid-modified polypropylene between the heat-adhesive resin layer of the seal portion and the lead-out terminal.
Any of the electrochemical devices. (5) The electrochemical device according to any one of (1) to (4), wherein the acid-modified polypropylene is applied as a dispersion dispersed in an organic solvent. (6) The above (1) to lithium ion secondary battery
The electrochemical device according to any one of (5). (7) The above (1) to the electric double-layer capacitor
The electrochemical device according to any one of (5).

[0010]

By using a lead terminal having a roughened surface, the adhesion between the heat seal resin on the innermost surface of the outer package and the lead terminal (aluminum, nickel, etc.) is improved, and the sealing property is improved. It is possible to obtain an electrochemical device such as a battery and an electric double layer capacitor excellent in liquid leakage resistance.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION An electrochemical device according to the present invention is an electrochemical device having an exterior body and an electrochemical element sealed in the exterior body, wherein the exterior body is thermally bonded to a metal layer. A laminate film having a conductive resin layer,
The electrochemical device has a lead-out terminal that is sealed and sealed by a heat-sealed seal portion between the heat-adhesive resin layers of the exterior body, and leads to the outside through the seal portion.
Any of the lead terminals has at least a portion corresponding to the seal portion roughened.

As described above, by roughening at least one of the sealing portions of the lead-out terminal, the adhesion to the laminate film becomes extremely good, and liquid leakage, gas leakage, and the like can be prevented. The lead terminals usually have two positive and negative terminals, but it is sufficient that at least one of them is roughened, and preferably all of them are roughened.

As the lead-out terminal, aluminum, nickel, copper, stainless steel or a metal wire or a metal foil having a surface treated with zinc, nickel, tin or the like is used. Is preferred.

The size of the lead-out terminal is not particularly limited, but usually, the width is 3 to 5 mm and the thickness is 50 to 50 mm.
It is about 100 μm. The length is not particularly limited, and may be a necessary length depending on the type and use of the electrochemical device, but is usually about 5 to 30 mm.

The surface roughening method includes chemical treatment such as alkali treatment, electrochemical treatment such as electrolysis, and mechanical treatment such as sand blast. Among them, a large amount of treatment is possible. Chemical treatment that can easily control the degree of the above is preferable. The surface roughening may be at least performed on a seal portion in contact with the laminate film or a part thereof, but may be performed on the entire lead-out terminal. When processing a part of the seal portion, it is more than 1/2, especially 2
It is desirable that at least / 3 be processed.

As for the degree of surface roughening, the average surface roughness R
a: 0.06 to 0.20 μm, particularly 0.065 to 0.1
It is preferably about 80 μm. When the surface is roughened by electrochemical treatment, the diameter of the formed pores is about 100 to 400 °. The pore density of the formed pores is preferably about 1 × 10 ⁷ to 2 × 10 ⁸ /0.5 mm ² .

The electrochemical element obtained by welding the roughened lead terminals to the positive and negative electrodes having the solid polymer electrolyte is inserted into a laminate film package, and the opening is heat-silled.

Next, the electrochemical device of the present invention will be described with reference to the drawings. FIG. 1 shows a schematic structure of the electrochemical device of the present invention. FIG.
FIG. 2 is a partial cross-sectional view taken along the line AA ′ in FIG.

The electrochemical device 1 shown in FIG.
The electrochemical element 10 shown in FIG. 1A is inserted into an outer package 20 formed in a bag shape by the first seal portion 21 shown in FIG. The second seal portion 22 is formed by housing the outer case 20 in a state of being protruded to the outside, and sealing the opened end surface of the exterior body 20 by heat fusion with the lead-out terminals 13 and 14 interposed therebetween. Electrochemical device 1
Has a structure in which the electrochemical element body 10 is sealed in the exterior body 20 and the lead-out terminals 13 and 14 protrude from the second seal portion 22 to the outside.

The electrochemical element 10 includes positive and negative electrodes 11 and 12 composed of a current collector such as an aluminum foil or a copper foil, and a solid polymer electrolyte (not shown). As shown in FIG. 1A, lead terminals 13 and 14 are connected to the positive and negative electrodes 11 and 12, respectively. Outgoing terminals 13, 14
Is a metal such as aluminum, copper, nickel, and stainless steel, and is configured in a lead shape having a rectangular or circular cross section. The lead-out terminals 13 and 14 conceptually have seal portions 13a and 14a in regions covered by the second seal portion 22, respectively.

The outer package 20 is made of a laminate film 30 in which a polyolefin resin layer such as polypropylene or polyethylene, a heat-resistant polyester resin layer, or the like is laminated as a heat-adhesive resin layer on both sides of a metal layer such as aluminum. It is configured. The exterior body 20 is shown in FIG.
As shown in FIG. 2, two laminated films 30 are previously heat-bonded to each other on the three sides of the thermo-adhesive resin layers to form a first seal portion 21, which is formed in a bag shape with one side opened. You. Alternatively, a single laminated film may be folded back and the both end faces may be thermally bonded to form a seal portion to form a bag.

In the second seal portion 22 of the electrochemical device 1 of the present invention, as shown in FIG. 2, the lead terminals 13 and 14 are sandwiched between the laminate films 30 constituting the exterior body 20. That is, the exterior body (sealed container) 20 is a laminated bag of a metal foil 20b such as an aluminum foil, a polyolefin (polypropylene or the like) film 20c inside the metal foil 20b, and an insulating film 20a such as a polyamide or polyester outside the metal foil. Is polyolefin film 20
c.

Also, the seal portions 13a, 14 facing the laminate film 30 on both sides of the lead-out terminals 13, 14 are provided.
a is an acid-modified polyolefin (acid-modified polypropylene, etc.)
15 are applied. The electrochemical element to which the lead-out terminals 13 and 14 are welded is housed in the exterior body 20 of the laminate film 30 having a polyolefin inside, and the leading ends of the lead-out terminals 13 and 14 are led out. As a result, the second seal portion (opening) 21 of the exterior body 20 is sealed by being heated and pressed (heat-sealed).

Heretofore, the adhesion between the lead terminal formed of a metal foil or the like and the heat-adhesive resin layer forming the outer package has been insufficient. In the electrochemical device 1 of the present invention, at least the sealing portions 13a and 14a of the lead-out terminals 13 and 14 are subjected to a roughening treatment, and a metal (aluminum, copper, nickel, stainless steel or the like) constituting the lead-out terminal is laminated with a resin or acid. It keeps adhesion to the modified polyolefin resin, and is extremely effective in drawing out the lead-out terminal from the laminate bag and achieving sealing.

Intermediate layer (acid-modified polyolefin resin layer) 1
Reference numeral 5 functions as a heat-adhesive resin layer because the lead terminals 13, 14 and the heat-adhesive resin layer of the laminate film 30 have excellent mutual adhesion. The thickness of the acid-modified polyolefin resin layer 15 is preferably about 3 to 100 μm. Examples of the acid-modified polyolefin resin include acid-modified polyethylene such as carboxylic acid, and acid-modified polypropylene obtained by graft-polymerizing maleic anhydride, and acid-modified polypropylene is particularly preferable.

As such a resin, an acid-modified polypropylene obtained by graft polymerization of maleic anhydride is known, and is sold, for example, by Mitsui Chemicals, Inc. under the trade name Admer. Among these admers, a polypropylene-type admer is particularly preferable, and particularly, as a homopolymer, QF305 (melting point: 160
° C), QF500 (melting point: 165 ° C), QF551 (melting point: 135 ° C) as a copolymer with ethylene, QB
540 (melting point: 150 ° C.), QB550 (melting point: 140)
° C) and QE060 (melting point: 139 ° C).

A similar resin is Modick manufactured by Mitsubishi Chemical Corporation.

Acid-modified polypropylene, which is a kind of acid-modified polyolefin, is sold, for example, by Mitsui Chemicals, Inc. under the trade name “UNISTOL (liquid polyolefin adhesive)”. Acid-modified polyolefins have carboxyl groups in the molecule, so metals (aluminum, steel,
Good adhesion to iron, stainless steel, etc.) and polyolefins.

In the intermediate layer 15 composed of such an acid-modified polyolefin resin layer, the sealing portions 13a, 1
4a. At the time of this lead-out terminal covering step, the lead-out terminal may be welded or bonded to the battery or the electric double layer capacitor before the electrolyte is injected, or may be a single terminal. In any case, it is necessary that the intermediate layer 15 of the present invention is formed and arranged on the lead-out terminals 13 and 14 before the electrolyte is injected.

In coating, the acid-modified polyolefin resin is preferably applied as a dispersion which is finely divided and dispersed in an organic solvent (dispersion medium) such as toluene. By using the dispersion, affinity with the surface of the roughened lead terminal is increased, and a stronger adhesive force can be obtained. The average primary particle diameter of the acid-modified polyolefin resin to be dispersed is preferably 5 to 15 μm.
It is about. As a method for applying the acid-modified polyolefin resin, it may be directly applied or printed, but spray is preferred.

As the dispersion dispersion medium, an organic solvent such as toluene and xylene is preferable. The amount of the dispersion dispersed in these solvents is preferably about 15 to 30% by weight based on the dispersion medium.

After the lead-out terminal coating step, the battery positive electrode and the battery negative electrode having the lead-out terminal subjected to the above treatment and the element having the polymer film are immersed in a lithium salt-containing organic electrolytic solution to be impregnated with the electrolytic solution. A liquid injection step is performed in which the polymer film is converted into a polymer solid electrolyte to produce an electrochemical element.

Then, the electrochemical element was inserted into a laminate bag made of metal and resin, and the opening was heat-sealed.
An electrochemical device is obtained by a sealing process.

In order to ensure insulation between the metal foil forming the laminate film and the lead-out terminal, the laminate film constituting the outer package is formed from the inner layer side with a heat-adhesive resin layer / polyester resin layer / metal foil / polyester. It is preferable to use a laminate film having a laminated structure of resin layers. By using such a laminated film, the high melting point polyester resin layer remains without melting at the time of thermal bonding, so that a separation distance between the lead terminal and the metal foil of the exterior body can be secured, and insulation can be ensured. . Therefore, the thickness of the polyester resin layer of the laminate film is preferably about 5 to 20 μm.

The electrochemical device of the present invention can be used as a lithium secondary battery or an electric double layer capacitor as described below.

<Lithium rechargeable battery> Lithium 2 of the present invention
Although the structure of the secondary battery is not particularly limited, it is generally composed of a positive electrode, a negative electrode, and a solid polymer electrolyte, and is suitably applied to a sheet-type battery, a cylindrical battery, and the like.

The electrode to be combined with the solid polymer electrolyte may be appropriately selected from those known as electrodes for lithium secondary batteries, and is preferably used as an electrode active material and a gel electrolyte. Is used.

For the negative electrode, a negative electrode active material such as a carbon material, a lithium metal, a lithium alloy or an oxide material is used. For the positive electrode, an oxide or the like capable of intercalating / deintercalating lithium ions is used. It is preferable to use a suitable positive electrode active material. By using such an electrode, a lithium secondary battery having excellent characteristics can be obtained.

The carbon material used as the electrode active material may be appropriately selected from, for example, mesocarbon microbeads (MCMB), natural or artificial graphite, resin fired carbon material, carbon black, carbon fiber and the like. These are used as powders. Above all, graphite is preferred, and its average particle size is preferably 1 to 30 μm, particularly preferably 5 to 25 μm.

Lithium ion is intercalated day
Intercalatable oxides include lithium
Composite oxides are preferred, for example, LiCoO_Two, LiM
n_TwoO _Four, LiNiO_Two, LiV_TwoO_FourAnd the like.
The average particle size of these oxide powders is about 1 to 40 μm.
It is preferred that

If necessary, a conductive additive is added to the electrode. Preferred examples of the conductive auxiliary agent include metals such as graphite, carbon black, carbon fiber, nickel, aluminum, copper, and silver. Particularly, graphite and carbon black are preferable.

The electrode composition of the positive electrode is as follows: active material: conductive auxiliary agent: gel electrolyte = 30 to 90: 3 to 10: 1 by weight.
The range of 0 to 70 is preferable. In the negative electrode, active material: conductive auxiliary agent: gel electrolyte = 30 to 90: 0 to 10: 1 by weight ratio.
A range from 0 to 70 is preferred. The gel electrolyte is not particularly limited, and a commonly used gel electrolyte may be used. Also,
An electrode containing no gel electrolyte is also preferably used. In this case, a fluorine resin, a fluorine rubber, or the like can be used as the binder, and the amount of the binder is about 3 to 30 wt%.

In the production of an electrode, first, an active material and, if necessary, a conductive auxiliary are dispersed in a gel electrolyte solution or a binder solution to prepare a coating solution.

Then, this electrode coating solution is applied to a current collector. The means for applying is not particularly limited, and may be determined as appropriate according to the material and shape of the current collector. Generally, a metal mask printing method, an electrostatic coating method, a dip coating method, a spray coating method, a roll coating method, a doctor blade method, a gravure coating method, a screen printing method, and the like are used.
Thereafter, if necessary, a rolling treatment is performed by a flat plate press, a calender roll, or the like.

The current collector may be appropriately selected from ordinary current collectors according to the shape of the device used by the battery, the method of disposing the current collector in the case, and the like. Generally, aluminum or the like is used for the positive electrode, and copper, nickel, or the like is used for the negative electrode.
Note that a metal foil, a metal mesh, or the like is generally used as the current collector. Although the metal mesh has lower contact resistance with the electrode than the metal foil, a sufficiently low contact resistance can be obtained even with the metal foil.

Then, the solvent is evaporated to produce an electrode. The coating thickness is preferably about 50 to 200 μm.

The polymer film is made of, for example, PEO (polyethylene oxide), PAN (polyacrylonitrile)
And a polymer microporous membrane such as PVDF (polyvinylidene fluoride).

The positive electrode, the polymer film, and the negative electrode are laminated in this order, and pressed to form a battery body.

The electrolyte for impregnating the polymer membrane generally comprises an electrolyte salt and a solvent. As the electrolyte salt, for example, Li
BF ₄ , LiPF ₆ , LiAsF ₆ , LiSO ₃ C
Lithium salts such as F ₃ , LiClO ₄ , and LiN (SO ₂ CF ₃ ) ₂ can be used.

The solvent of the electrolytic solution is not particularly limited as long as it has good compatibility with the above-mentioned solid polymer electrolyte and electrolyte salt, but in a lithium battery or the like, a polar organic solvent which does not decompose even at a high operating voltage. Solvents, for example, ethylene carbonate (abbreviation EC), propylene carbonate (abbreviation PC), butylene carbonate, dimethyl carbonate (abbreviation DMC), diethyl carbonate (abbreviation DE)
C), carbonates such as ethyl methyl carbonate (abbreviated MEC), cyclic ethers such as tetrahydrofuran (THF) and 2-methyltetrahydrofuran, cyclic ethers such as 1,3-dioxolan and 4-methyldioxolan, and γ-butyrolactone Lactone, sulfolane and the like are preferably used. 3-methylsulfolane, dimethoxyethane, diethoxyethane, ethoxymethoxyethane,
Ethyl diglyme or the like may be used.

When a microporous polymer film is immersed in such an electrolytic solution, the polymer film absorbs the electrolytic solution and gels to form a solid polymer electrolyte.

When the composition of the polymer solid electrolyte is represented by polymer / electrolyte, the ratio of the electrolyte is preferably 40 to 90% by weight in view of the strength of the membrane and the ionic conductivity.

<Electric Double Layer Capacitor> The electric 2 of the present invention
Although the structure of the multilayer capacitor is not particularly limited, usually, a pair of polarizable electrodes are arranged via a polymer solid electrolyte, and an insulating gasket is arranged around the polarizable electrode and the polymer solid electrolyte. I have. Such electricity 2
The multilayer capacitor may be any type called a coin type, a sheet type, a laminated type, or the like.

As the polarizable electrode, activated carbon, activated carbon fiber, or the like is used as an active material, and a fluorocarbon resin,
Add fluoro rubber etc. Then, it is preferable to use the mixture formed on a sheet-like electrode. The amount of the binder is about 5 to 15 wt%. Further, a gel electrolyte may be used as the binder.

The current collector used for the polarizable electrode may be a conductive rubber such as a conductive butyl rubber or the like, or may be formed by spraying a metal such as aluminum or nickel. A metal mesh may be provided.

The electric double layer capacitor is formed by combining the above-described polarizable electrode and the solid polymer electrolyte.

The polymer film is made of, for example, PEO (polyethylene oxide), PAN (polyacrylonitrile)
And a polymer microporous membrane such as PVDF (polyvinylidene fluoride).

As the electrolyte salt, (C ₂ H ₅ ) ₄ NB
F ₄ , (C ₂ H ₅ ) ₃ CH ₃ NBF ₄ , (C ₂ H ₅ ) ₄ PB
F _4, and the like.

The non-aqueous solvent used for the electrolytic solution may be various known ones, and propylene carbonate, ethylene carbonate, γ-
Butyrolactone, acetonitrile, dimethylformamide, 1,2-dimethoxyethane, sulfolane alone or a mixed solvent is preferred.

When a microporous polymer film is immersed in such an electrolytic solution, the polymer film absorbs the electrolytic solution and gels to form a solid polymer electrolyte.

When the composition of the polymer solid electrolyte is represented by polymer / electrolyte, the ratio of the electrolyte is preferably 40 to 90% by weight in view of the strength of the membrane and the ionic conductivity.

As the insulating gasket, an insulator such as polypropylene or butyl rubber may be used.

[0063]

[Example 1] (Preparation of battery) An aluminum foil roughened by etching with an alkali was used as a positive electrode terminal. Nickel foil not particularly roughened was used for the negative electrode terminal. In addition, in order to improve the adhesiveness between the heat seal resin on the innermost surface of the outer package and the terminals (aluminum, nickel), acid-modified polypropylene was applied to the surfaces of these terminals. At this time, the average surface roughness Ra of the roughened portion of the terminal is 0.066.
μm.

As an acid-modified polypropylene which is a kind of acid-modified polyolefin, “UNISTOL” manufactured by Mitsui Chemicals, Inc.
R-200 "was used. Unistor R-200 is a dispersion in which acid-modified polypropylene fine particles are dispersed in toluene (25 wt% of acid-modified polypropylene fine particles (average primary particle size: 10 μm) are added to toluene). Unistor R-200 is about 4mm wide, about 40mm long and 0.08mm thick
Was spray-coated on the aluminum foil and the nickel foil. After the application, the film was placed in a drying oven at 200 ° C. for 20 minutes and adhered. These foils become the external connection terminals 13 and 14.

The electrodes were LiCoO ₂ , carbon black (HS-100, manufactured by Denki Kagaku Kogyo), PVDF
(Polyvinylidene fluoride) was applied to an aluminum foil by a doctor blade method to prepare. The negative electrode is mesocarbon microbeads (MCMB), HS-10
0, made of PVDF was applied to copper foil by a doctor blade method. A microporous PVDF membrane was used as a polymer solid electrolyte. Positive and negative electrodes are 31 mm wide and 41 mm long
Cut into pieces. The separator was cut into a width of 33 mm and a length of 43 mm.

The battery body was prepared as follows. First, the positive electrode and the separator were laminated and laminated by hot pressing.
The laminating conditions were 150 ° C. and a pressure of 5 kgcm ⁻² for 2 minutes. A negative electrode was laminated thereon and laminated similarly.

The aluminum current collector of this battery element was resistance-welded with the above-mentioned aluminum output terminal, and the copper current collector was similarly resistance-welded with the above-mentioned nickel output terminal. This battery element is EC
(Ethylene carbonate) and DMC (dimethyl carbonate) were immersed for 30 minutes in 330 ml of an electrolyte obtained by dissolving 1 M of LiPF _{6 in} a mixed solvent of 1: 2 by volume. After taking out the battery body from the electrolyte, the electrolyte adhering to the electrode surface was wiped off. This battery element absorbed the electrolytic solution and became a gel state. PET (12 μm) / aluminum (20 μm) / PET (12 μm) / PP (80 μm)
The battery element was inserted into a laminate bag (the innermost layer was PP), and the opening was heat-sealed to produce 100 sheet-type polymer lithium secondary batteries. In the above, PET: polyethylene terephthalate, PP: polypropylene.

Table 1 shows the number of leaks when each sample was fully charged and stored at room temperature for 90 days. As is clear from Table 1, all the batteries of the present invention did not cause liquid leakage.

[0069]

[Table 1]

Example 2 In Example 1, an aluminum foil roughened by etching with acid was used as a positive electrode terminal, and a nickel foil roughened by etching with acid was used as a negative electrode terminal. At this time, the average surface roughness Ra of the roughened portions of the positive and negative terminals was 0.15 μm in both cases. Otherwise, a sheet-type polymer lithium ion secondary battery was prepared and evaluated in the same manner as in Example 1. As a result, no battery leaked. Table 1 shows the results.

Comparative Example 1 The procedure of Example 1 was repeated except that unsmoothed aluminum foil and nickel foil were coated with Unistor R-200, which is an acid-modified polypropylene, as terminals. In the same manner as in Example 1, a sheet-type polymer lithium ion secondary battery was prepared and evaluated. As a result, the number of leaked batteries was 10. Table 1 shows the results.

Example 3 (Preparation of Capacitor) Active Material: Activated Carbon Powder, Conductive Aid: Acetylene Black, Polymer: PVDF [KynarFlex 2801 (manufactured by Elf Atochem)], (Polyvinylidene fluoride and 6 A polymer solution was prepared by mixing solvent: acetone in a weight ratio of active material: conducting auxiliary agent: polymer: solvent = 8: 1: 1: 15. This was applied to an aluminum foil to form positive and negative electrodes.

A microporous PVDF membrane was used as a polymer solid electrolyte.

Next, the positive electrode and the negative electrode were laminated via a polymer solid electrolyte, and the positive and negative electrodes were welded with the aluminum terminals used in Example 1 and then impregnated with an electrolytic solution. did. The electrolyte used was a solution prepared by dissolving 4-ethylammonium tetrafluoroborate at a concentration of 1 M in propylene carbonate.

Otherwise, the procedure of Example 1 was followed to obtain a capacitor 1. Example 2 A capacitor 2 and a comparative capacitor 1 were manufactured in the same manner as in Comparative Example 1.

The obtained capacitors 1 and 2 and comparative capacitor 1 were evaluated in the same manner as in Example 1. As a result, almost the same results as in the above Examples and Comparative Examples were obtained.

[0077]

As described above, according to the electrochemical device of the present invention, it is possible to provide an electrochemical device having excellent sealing properties and excellent liquid leakage resistance, and a method for producing the same.

[Brief description of the drawings]

FIG. 1 shows the structure of the electrochemical device of the present invention,
(A) is a plan view showing electrodes and lead-out terminals constituting the electrochemical element body, (b) is a plan view showing an exterior body, and (c) is an electric element constituted by enclosing the electrochemical element in the exterior body. It is a top view which shows a chemical device.

FIG. 2 is a partial cross-sectional view taken along line AA of FIG. 1 (c).

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 electrochemical device 10 electrochemical element 11, 12 electrode 13, 14 lead-out terminal 13 a, 14 a seal portion 15 intermediate layer 20 exterior body 21 first seal portion 22 second seal portion 30 laminate film

 ──────────────────────────────────────────────────続 き Continued on the front page F-term (reference) 5H011 AA17 CC02 CC06 CC10 DD13 EE04 FF04 GG01 GG08 HH02 JJ08 JJ15 KK01 5H029 AJ15 AK03 AL02 AL06 AL07 AL12 AM02 AM03 AM04 AM07 AM16 BJ04 CJ05 CJ22 CJ25 DJ02 DJ01 DJ01 DJ01 DJ03 DJ04

Claims (7)

[Claims] 1. An electrochemical device having an exterior body and an electrochemical element enclosed in the exterior body, wherein the exterior body is a laminate film having a metal layer and a heat-adhesive resin layer, The electrochemical device has a lead-out terminal which is sealed and sealed by a heat-sealed seal portion between the heat-adhesive resin layers of the exterior body, and is led out through the seal portion. Either is an electrochemical device in which at least a portion corresponding to the seal portion is roughened. 2. The lead terminal has a surface roughness Ra = 0.0.
2. The electrochemical device according to claim 1, which is roughened to a roughness of 6 to 0.20 [mu] m. 3. The electrochemical device according to claim 1, wherein the heat-adhesive resin layer of the laminate film is a polypropylene resin. 4. An acid-modified polypropylene between the heat-adhesive resin layer of the seal portion and the lead-out terminal.
Any of the electrochemical devices. 5. The electrochemical device according to claim 1, wherein the acid-modified polypropylene is applied as a dispersion dispersed in an organic solvent. 6. A lithium ion secondary battery according to claim 1.
The electrochemical device according to any one of items 1 to 5, 7. An electric double-layer capacitor.
5. The electrochemical device according to any one of 5.