JP6647349B2 - Method of manufacturing electrode lead wire member for non-aqueous battery - Google Patents

Description

The present invention relates to a method for manufacturing an electrode lead wire member for a non-aqueous battery using an organic electrolyte as an electrolyte for a secondary battery such as a lithium ion battery or an electric double layer capacitor (hereinafter referred to as a capacitor).

In recent years, with the rise of global environmental problems, the spread of electric vehicles and the effective use of natural energy such as wind power and solar power have become issues. Accordingly, in these technical fields, secondary batteries such as lithium ion batteries and capacitors have attracted attention as storage batteries for storing electric energy. In addition, the outer container that stores the lithium ion battery used for electric vehicles, etc., has a flat bag created by using a battery exterior laminate in which aluminum foil and a resin film are laminated, or is drawn or stretched. A molded container is used to reduce the thickness and weight.
By the way, the electrolyte of a lithium ion battery has the property of being susceptible to moisture and light. For this reason, as a packaging material for a lithium ion battery, a battery packaging laminate excellent in waterproofness and light shielding properties, in which a base layer made of polyamide or polyester and an aluminum foil are laminated, is used.

  In order to store a lithium ion battery in a storage container prepared using such a battery exterior laminate, for example, as shown in FIG. The tray-like shape having the base 31 is formed by drawing or the like, and accessories such as a lithium ion battery (not shown) and electrodes are accommodated in the recess 31 of the tray. Next, as shown in FIG. 3 (b), the battery is wrapped with a lid member 33 made of a laminate for battery exterior stacked from above, and the tray flange portion 32 and the four side edges 34 of the lid member 33 are heat-sealed. And seal the battery. In the storage container 35 formed by such a method of mounting the batteries in the recesses 31 of the tray, the batteries can be stored from above, so that the productivity is high.

In the above-described loading container 30 of the lithium ion battery shown in FIG. 3A, the depth of the tray (hereinafter, the depth of the tray is sometimes referred to as “squeezing”) is conventionally the same as that of a small lithium ion battery. Was about 5 to 6 mm. However, in recent years, storage containers for large batteries have been demanded for applications such as electric vehicles. In order to manufacture a storage container for a large battery, it is necessary to form a tray with a deeper drawing, which is increasing technical difficulty.
In addition, when moisture enters the inside of the lithium ion battery, the electrolyte is decomposed by the moisture and a strong acid is generated. In this case, the strong acid generated from the inside of the battery exterior laminate penetrates, and as a result, the aluminum foil is corroded and deteriorated by the strong acid, electrolyte leakage occurs, and the battery performance deteriorates only. However, there is a problem that the lithium ion battery may ignite.

JP 2000-357494 A

  As a measure for preventing the surface layer of the aluminum foil and the electrode lead wire member constituting the above-mentioned laminate for battery exterior from being corroded by a strong acid, Patent Document 1 discloses that the surface of the aluminum foil is subjected to a chromate treatment. Although measures to improve the corrosion resistance by forming a chromium treatment film are disclosed, the chromate treatment is a problem from the viewpoint of environmental measures because chromium, which is a heavy metal, is used. It cannot be used because it is a harmful substance, and a chromate treatment solution of trivalent chromium is used. Further, there is a problem that the effect of improving the corrosion resistance is small in the chemical conversion treatment other than the chromate treatment.

  In the conventional electrode lead wire member, of both the positive electrode and the negative electrode, the aluminum material as the positive electrode member has good electrolytic solution resistance, but the copper plate as the negative electrode member has nickel plating on the surface layer. And further chromate treatment of trivalent chromium results in poor electrolytic solution resistance.

The present invention has been made in view of the above circumstances, and even if the electrolytic solution of a lithium ion battery reacts with moisture to generate hydrofluoric acid and increases the corrosiveness, avoids the adverse effect of the lithium ion battery and avoids the adverse effects. It is an object of the present invention to provide a method of manufacturing an electrode lead wire member for a non-aqueous battery with improved corrosion resistance so as to extend the life of the battery.

  The present invention provides a storage container for a non-aqueous battery using an organic electrolyte as an electrolytic solution, in a portion where a laminate film laminate of an exterior material is joined to an electrode lead wire member, on an outer surface of the electrode lead wire member, The technical idea is to improve the corrosion resistance against a corrosive electrolytic solution by laminating a thin film coating layer in a pattern in the manner described above. The thin film coating layer is made of a resin having a hydroxyl group-containing polyvinyl alcohol skeleton or a copolymer resin thereof.

In order to solve the above-mentioned problems, the present invention is a method for manufacturing an electrode lead wire member drawn out of a non-aqueous battery storage container, comprising: a corrosion-resistant thin-film coating layer on a surface of a metal lead-out portion ; Layers are sequentially laminated, the thin film coating layer contains a resin having a skeleton of a hydroxyl group-containing polyvinyl alcohol or a copolymer resin thereof, and a substance made of a metal fluoride or a derivative thereof, A thin-film coating layer is formed on the surface of the lead-out portion by printing on the surface of the lead-out portion, along a direction in which the sealant layer is stacked so as to intersect the longitudinal direction of the lead-out portion, and is formed in a band-like pattern wider than the sealant layer. becomes, the thin film coating layer was heated and dried, producing side of the electrode lead wire member characterized by comprising by water by Rukoto crosslinked or amorphized To provide.

  Further, it is preferable that the thin film coating layer contains a substance which is made of a metal fluoride or a derivative thereof and has a hydroxyl group-containing resin having a skeleton of polyvinyl alcohol or a copolymer resin thereof, which crosslinks the thin film coating layer.

In addition, it is preferable that the metal fluoride or a derivative thereof is a substance containing an F ⁻ ion that forms a passivation of aluminum fluoride.

  Further, the thin film coating layer is formed on the surface of the lead-out portion by printing on the surface of the lead-out portion, in a direction in which the sealant layer intersects in the longitudinal direction of the lead-out portion and is laminated into a band-like pattern wider than the sealant layer. Preferably, it is formed. As a result, the thin film coating layer is not attached to the junction between the current collector inside the non-aqueous battery and the electrode lead wire member, or the portion where the non-aqueous battery is joined in series or in parallel, so that joining by ultrasonic waves or resistance welding is performed. In this case, since there is no thin film coating layer at the joining portion, there is an advantage that the joining property is improved.

  Further, the sealant layer is preferably a maleic anhydride-modified polyolefin-based resin film or an epoxy functional group-modified polyolefin-based resin film.

  Further, the thickness of the sealant layer is 50 μm or more and 300 μm or less, and the thickness of the thin film coating layer is 0.1 to 5.0 μm, and the lead-out portion on which the thin film coating layer is formed and the thin film coating layer The peel strength between the sealant layer and the sealant layer laminated thereon is measured by a peeling measurement method A specified in JIS C6471, and is preferably 40 N / inch or more.

  In addition, it is preferable that both ends of the electrode lead wire member as viewed in a cross section along the bonding portion with the exterior material are crushed to be thinner than a central portion of the cross section.

The electrode lead wire member, a thin film coating layer made of a resin having a hydroxyl group-containing polyvinyl alcohol skeleton or a copolymer resin thereof, is heat-treated, crosslinked or non-crystallized to have water resistance, and the electrode lead wire member has It is possible to suppress leakage of the electrolytic solution from both ends viewed from the cross section to the outside and entry of moisture in the atmosphere into the inside.
When both ends of the electrode lead wire member viewed in cross section are crushed and made thinner than the center portion of the cross section, the adhesion between the electrode lead wire member and the laminate film laminate is improved, and the gap portion is reduced. Thus, leakage of the electrolyte to the outside and entry of moisture in the atmosphere into the inside are reduced.

It is a perspective view showing an example of a storage container for batteries. It is a schematic sectional drawing which shows an example of the battery exterior laminated body used for a battery storage container. It is a perspective view which shows the process of putting a lithium ion battery in a storage container in order. (A) is a perspective view showing an example of an electrode lead wire member according to the present invention, and (b) is a cross-sectional view taken along line SS of (a). It is a top view showing an example of an electrode lead member concerning the present invention. It is a measurement result which measured the thin film coating layer with the differential thermal analyzer.

The electrode lead wire member according to the present invention will be described with reference to FIGS. 1 and 2 by taking as an example a case where the electrode lead wire member is drawn out of a storage container for a lithium ion battery manufactured using the battery exterior laminate.
As shown in FIG. 1, the electrode lead wire member 18 and the lithium ion battery 17 of the present invention are contained in a battery outer container 20 formed by folding the battery outer laminate 10.
Furthermore, the three side edges 19 of the battery outer container 20 are heat-sealed to form a bag. The electrode lead member 18 is drawn out of the battery outer container 20 as shown in FIG. FIG. 3 shows a method of storing the lithium ion battery in the battery container manufactured using the electrode lead wire member 18 according to the present invention.

As shown in FIG. 2, the battery exterior laminate 10 composed of a laminate film laminate has a base layer 11, an aluminum foil 12, and a resin film 13 adhered through adhesive layers 15 and 16, respectively. ing.
As shown in FIG. 4, the electrode lead wire member 18 includes a lead-out portion 21 made of aluminum or a nickel-plated copper plate. On the surface of the lead-out portion 21, the sealant layer 23 has a skeleton of a hydroxyl-containing polyvinyl alcohol. Are laminated via a corrosion-resistant thin-film coating layer 22 made of a resin having the above formula or a copolymer resin thereof.
The thin film coating layer 22 is made of a metal fluoride or a derivative thereof, and is a substance that crosslinks the thin film coating layer made of a resin having a hydroxyl group-containing polyvinyl alcohol skeleton or a copolymer resin thereof and activates the metal surface. Is contained. However, even if metal fluoride or a derivative thereof is not contained, the corrosion resistance of the thin film coating layer is improved.
The thin film coating layer 22 is formed in a pattern on the surface of the lead-out portion 21 by printing.
The thin film coating layer 22 formed on the surface of the lead-out portion 21 is made water-resistant by crosslinking or amorphizing by heat treatment.
In addition, by using a substance that is liberated and acidic in an aqueous solution state, such as metal fluoride, contained in the thin film coating layer, the metal surface is activated, and the metal surface and the film of the thin film coating layer are activated. Are strongly bonded.
By the way, it is known that a thin film coating layer made of a resin having a skeleton of polyvinyl alcohol or a copolymer resin thereof generally has good gas barrier properties. Since the inside of the resin that constitutes the thin film coating layer has few voids, especially in low-humidity atmospheres, it has gas barrier properties even for gas molecules with a small molecular diameter such as hydrogen gas, so it can be used like lithium batteries and capacitors. When a thin film coating layer is used as a component inside a battery in which no water is present in a battery using a non-aqueous electrolyte, it is considered that the barrier property against the electrolyte and moisture is high. Therefore, it has a high barrier property against a substance that corrodes a metal surface such as hydrofluoric acid, and is therefore expected to have an effect of preventing corrosion. As described above, the thin film coating layer formed of a resin having a skeleton of polyvinyl alcohol or a copolymer resin thereof selected from the hydroxyl group-containing substances can improve the corrosion resistance by crosslinking.

The lead portion 21 of the electrode lead member 18 is generally made of an aluminum plate for the positive electrode and a metal obtained by coating a copper plate with nickel plating for the negative electrode. In order to facilitate thermal bonding with the battery exterior laminate 10 made of an aluminum laminate film, a sealant layer 23 is formed and placed in advance at the joint of the electrode lead wire member 18. The sealant layer 23 is preferably laminated on both sides so as to sandwich the lead-out portion 21 from both sides.
If the corrosion-resistant thin-film coating layer 22 is not formed on the surface of the lead-out part 21, the permeation of the electrolytic solution causes a reaction between water and the electrolyte on the surface of the lead-out part 21 to generate hydrofluoric acid. It is said that the corrosion of the portion 21 deteriorates the adhesion. Therefore, it is preferable that the thin layer coating layer 22 made of a resin having a skeleton of hydroxyl group-containing polyvinyl alcohol or a copolymer resin thereof is laminated on at least the surface layer on the battery side of the lead-out portion 21. As shown in FIG. 4B, it is necessary to laminate the thin film coating layer 22 on the entire outer peripheral portion of the cross section of the lead-out portion 21 at the joint portion with the exterior material.
Chromate treatment is widely used as a corrosion prevention measure against electrolytic solution for an aluminum lead-out portion 21 used for an electrode lead wire member according to the prior art. The effect of the chromate treatment is small for the lead-out portion 21 in which nickel is plated. However, it has been found that the electrode lead wire member 18 according to the present invention also has an effect of preventing corrosion with respect to the electrolytic solution with respect to the lead-out portion 21 in which nickel is plated on copper.
From this, it is considered that the mechanism for preventing corrosion of the electrolytic solution by the thin film coating layer 22 of the present invention is different from that of the conventional chromate treatment.
As shown in FIG. 5, the sealant layer 23 may be laminated so as to extend over both the positive electrode and the negative electrode. Thereby, an electrode lead member in which the positive electrode and the negative electrode are integrated can be obtained. Further, since the corrosion prevention effect of the thin film coating layer 22 can be obtained for various metal plates such as an aluminum plate and a nickel-plated copper plate, it is preferable to provide the thin film coating layer 22 on both the lead-out portions 21 of the positive electrode and the negative electrode.

The resin having a hydroxyl group-containing polyvinyl alcohol skeleton or a copolymer resin thereof is a resin obtained by saponifying a polymer of a vinyl ester monomer or a copolymer thereof. Examples of vinyl ester monomers include fatty acid vinyl esters such as vinyl formate, vinyl acetate, and vinyl butyrate, and aromatic vinyl esters such as vinyl benzoate. Other monomers to be copolymerized include ethylene, propylene, α-olefins, unsaturated acids such as acrylic acid, methacrylic acid, and maleic anhydride, and vinyl halides such as vinyl chloride and vinylidene chloride. Commercially available products include those manufactured by Nippon Synthetic Chemical Co., Ltd.
It is preferable that the thin film coating layer 22 contains a substance that crosslinks the thin film coating layer made of a metal fluoride or a derivative thereof and having a hydroxyl group-containing polyvinyl alcohol skeleton or a copolymer resin thereof. Examples of the metal fluoride or a derivative thereof include chromium fluoride, iron fluoride, zirconium fluoride, titanium fluoride, hafnium fluoride, zircon hydrofluoric acid and salts thereof, titanium hydrofluoric acid and salts thereof, and the like. Fluoride. These metal fluorides or derivatives thereof, both a material to crosslink the resin or a copolymer resin having a skeleton of polyvinyl alcohol having a hydroxyl group, F to form an aluminum fluoride is passivated ^- ions Since the lead-out portion 21 is made of aluminum, it is considered that the surface of the lead-out portion 21 can be passivated to enhance the effect of preventing corrosion.

In order to form the thin film coating layer 22 on the surface of the lead-out portion 21, for example, a non-crystalline polymer having a skeleton of hydroxyl group-containing polyvinyl alcohol (manufactured by Nippon Synthetic Chemical Co., Ltd.) is 0.2 to 6 wt%. And an aqueous solution in which 0.1 to 3 wt% of chromium (III) fluoride is dissolved, and applied so that the thickness after drying becomes about 0.1 to 5 μm, and then further heat drying and baking in an oven. By performing the crosslinking, the thin film coating layer 22 can be formed.
FIG. 6 shows the thickness after drying using an aqueous solution in which 3 wt% of an amorphous polymer having a hydroxyl group-containing polyvinyl alcohol skeleton (manufactured by Nippon Synthetic Chemical Co., Ltd.) and 1 wt% of chromium (III) fluoride are dissolved. The following shows an example of the result of measurement of a thin film coating layer which was applied so that the thickness became 3 μm and further dried by heating in a 200 ° C. oven using a differential thermal analyzer. When the melting point was confirmed, it was found that there was no peak of the melting point, so that crosslinking had occurred.

As described above, when the thin film coating layer 22 is laminated on the surface of the lead-out portion 21, the pressure resistance of the thin film coating layer 22 is high, so that even if the thickness of the polypropylene layer or the polyethylene layer as the sealant layer 23 is reduced. Since the pressure resistance can be maintained, the penetration of moisture into the inside of the lithium-ion battery from the edge portion (side edge portion) of the lead-out portion 21 is reduced, and the deterioration of the lithium-ion battery electrolyte over time is reduced, thereby shortening the product life of the battery. become longer.
Furthermore, even when a very small amount of water enters the battery and the electrolytic solution and the water react to decompose and the electrolytic solution is decomposed to generate hydrofluoric acid, it contains a hydroxyl group laminated on the surface of the lead-out portion 21. Since the thin film coating layer 22 made of a resin having a skeleton of polyvinyl alcohol or a copolymer resin thereof has a small free volume, it has a high gas barrier property, and can diffuse to the outside along the sealant layer, and a small amount of hydrofluoric acid can be formed. Even if it comes into contact with the surface of the aluminum plate, which is the lead-out portion 21, corrosion of the lead-out portion 21 is prevented by the passivation film formed on the surface of the aluminum plate, and interlayer bonding between the lead-out portion 21 and the sealant layer 23 is performed. The strength is maintained, the pressure strength is increased, and problems such as battery leakage do not occur.

The thickness of the sealant layer 23 to be joined in advance is preferably 50 to 300 μm, and most preferably 50 to 150 μm in consideration of waterproofness. If the thickness of the lead-out part 21 is 200 μm or more, a through hole may be formed at the edge of the lead-out part 21 and the electrolyte may not be sealed. Therefore, as shown in FIG. 4 (b), both ends 24 of the lead-out portion 21 as viewed in a cross section along the joint with the exterior material may be crushed to be thinner than the center of the cross section. preferable. Thereby, the thickness of the sealant layer 23 to be joined in advance can be reduced.
The thickness of the thin film coating layer 22 composed of a resin having a hydroxyl group-containing polyvinyl alcohol skeleton or a copolymer resin thereof is preferably 0.1 to 5.0 μm, more preferably 0.5 to 3 μm. With the thickness of the thin film coating layer, the performance of moisture proof and adhesive strength is increased.

The thin film coating layer 22 is applied to a necessary portion of the lead-out section 21 by a printing method. As a printing method, a known printing method such as an ink jet method, a dispenser method, and a spray coat method can be used. The printing method that can be used in the present invention is arbitrary. However, since it is necessary to print not only the surface layer of the lead-out portion 21 but also the edge portion of the electrode lead member viewed from the cross section, an ink jet method and a dispenser method are preferable. In particular, in a dispenser method, when an experiment was performed using a coating head capable of printing with a width as thin as about 10 mm, it was found that the method was the most suitable method.
As the sealant layer 23 to be bonded to the electrode lead wire member in advance, it is preferable to use the same or similar resin film as the resin film 13 used as the innermost layer of the aluminum laminated film 10, and the resin film 13 is generally used. In the case of polypropylene, the sealant layer 23 is made of unstretched polypropylene (CPP), a film of maleic anhydride-modified propylene alone, or a film of polypropylene modified with a monomer having an epoxy functional group such as glycidyl methacrylate. , And a multilayer film of this and polypropylene. Even when the resin film 13 is polyethylene, the sealant layer 23 may be polyethylene, maleic anhydride-modified polyethylene, or polyethylene alone modified with a monomer having an epoxy functional group such as glycidyl methacrylate. And a multilayer film with the copolymer thereof. In this case, a maleic anhydride or acrylic acid copolymer, polyethylene modified with glycidyl methacrylate, or the like may be used on the surface that comes into contact with the electrolytic solution.

  Examples of the non-aqueous battery to which the present invention is applied include a battery using an organic electrolyte for an electrolyte such as a lithium ion battery or an electric double layer capacitor as a secondary battery. As the organic electrolyte, a medium using a carbonate such as propylene carbonate (PC), diethyl carbonate (DEC), or ethylene carbonate as a medium is generally used, but is not particularly limited to this.

(Measuring method)
-Measuring method of adhesive strength between lead-out part of electrode lead wire member and sealant layer: JIS C6471 "Copper clad laminate test for flexible printed wiring board" using a measurement sample obtained by heat sealing an aluminum laminate film on the sealant layer The method was used for measurement.
Method for measuring electrolyte strength retention: A 50 × 50 mm (heat seal width: 5 mm) four-sided bag was formed using the battery exterior laminate, and 1 mol / liter of LiPF ₆ was added thereto. 0.5 wt% of pure water was added to the PC / DEC electrolyte, and 2 cc of the pure water was weighed, filled and packaged. In this four-sided bag, a thin-film coating layer is printed on a part of the surface of the lead-out portion of the electrode lead member by a dispenser method, and a sealant layer is laminated on the thin-film coating layer by heat sealing. After the members are put in the oven at 60 ° C. for 100 hours, the interlayer adhesive strength (k2) between the thin film coating layer and the sealant layer of the electrode lead wire member is measured.
Here, the interlayer adhesion strength (k1) between the thin film coating layer before exposure to the electrolyte solution and the polypropylene (PP) film as the sealant layer, which was measured in advance, and the interlayer adhesion after exposure to the electrolyte solution The ratio with the strength (k2) was defined as an electrolyte strength holding ratio K = (k2 / k1) × 100 (%).
(measuring device)
・ Measurement device for adhesive strength: Shimadzu Corporation, Model: AUTOGRAPH AGS-100A tensile tester

(Example 1)
As a lead portion of the electrode lead wire member for the lithium battery, an aluminum piece obtained by cutting an aluminum plate having a thickness of 200 μm into a size of 50 mm × 60 mm was used. An aqueous solution obtained by dissolving 3 wt% of an amorphous polymer having a hydroxyl group-containing polyvinyl alcohol skeleton (manufactured by Nippon Synthetic Chemical Industry Co., Ltd.) and 1 wt% of chromium (III) fluoride on the surface of the degreased and washed aluminum piece. It was applied on both sides with a 10 μm width type dispenser with a thickness of 1 μm, a thin film coating layer was laminated, and further dried by heating in an oven at 200 ° C., and the resin of the thin film coating layer was baked and crosslinked at the same time. At this time, it was confirmed that the thin-film coating layer was applied not only to the front and back surface layers of the lead-out portion but also to both end surfaces of the lead-out portion.
Furthermore, a monolayer film of a maleic anhydride-modified polypropylene film (polypropylene resin manufactured by Mitsui Chemicals, product name / Admer QE060, formed into a film of 100 μm by a film forming machine) is used on the thin film coating layer on the surface of the outlet portion. ) Was joined by heat sealing to obtain an electrode lead wire member of Example 1.
A 120-μm-thick aluminum laminate film made of aluminum foil (thickness: 20 μm) / maleic anhydride-modified polypropylene film (thickness: 100 μm) was heat-sealed on the sealant layer of the electrode lead wire member of Example 1. A measurement sample using the electrode lead wire member was manufactured.
A test piece for measuring adhesive strength was taken from the measurement sample of Example 1, and the adhesive strength between the lead-out portion and the sealant layer was measured. As a result, an adhesive strength of 46 N / inch was shown.
The result of measuring the electrolyte solution strength retention K of the measurement sample of Example 1 was K = 88%.

(Example 2)
As a lead-out portion of an electrode lead wire member for a lithium battery, a surface of a copper plate piece (size: 50 mm × 60 mm) having a thickness of 200 μm is plated with nickel sulfamic acid plating to a thickness of 2 to 5 μm, and a part thereof contains a hydroxyl group. An amorphous polymer having a skeleton of polyvinyl alcohol (manufactured by Nippon Synthetic Chemical Co., Ltd.) having a thickness of 1 μm is applied using an aqueous solution in which 3% by weight and chromium (III) fluoride are dissolved by 1% by weight. The layers were laminated and further dried by heating in an oven at 200 ° C., and the resin of the thin film coating layer was baked and crosslinked at the same time.
Further, a maleic anhydride-modified polypropylene film single layer (polypropylene resin manufactured by Mitsui Chemicals, product name / Admer QE060 was used to form a 100 μm film using a film forming machine) on the thin film coating layer on the surface of the outlet portion. The two-sided heat bonding was performed by heat sealing to obtain an electrode lead wire member of Example 2.
Using the electrode lead wire member of Example 2, the aluminum laminate film was heat-sealed in the same manner as in Example 1 to obtain a measurement sample of Example 2, and the adhesive strength between the lead portion and the sealant layer was measured. It showed an adhesive strength of 44 N / inch.
In addition, as a result of measuring the electrolyte solution strength retention K for a part of the battery storage container of Example 2, the result was K = 78%.

(Comparative Example 1)
An electrode lead wire member of Comparative Example 1 and a measurement sample were obtained in the same manner as in Example 1 except that the thin film coating layer was not laminated on the aluminum plate, and the adhesive strength between the lead portion and the sealant layer was measured. Inch adhesive strength was shown. The measurement result of the electrolyte solution strength retention K of the measurement sample of Comparative Example 1 was K = 10% or less.

(Comparative Example 2)
As a lead portion of an electrode lead wire member for a lithium battery, a surface of a copper plate piece (size: 50 mm × 60 mm) having a thickness of 200 μm is plated with nickel sulfamate having a thickness of about 2 to 5 μm, and a part of polyvinyl chloride containing a hydroxyl group is provided. An amorphous polymer having a skeleton of alcohol (manufactured by Nippon Synthetic Chemical Co., Ltd.) was applied to a thickness of 1 μm using a paint in which 3 wt% and chromium (III) fluoride were mixed at 1 wt%, and a thin film coating layer was laminated. . An electrode lead wire member and a measurement sample of Comparative Example 2 were obtained in the same manner as in Example 1, except that the heat drying treatment was not performed after the lamination.
When the adhesive strength between the lead-out portion and the sealant layer was measured for the electrode lead wire member and the measurement sample of Comparative Example 2, the adhesive strength was 46 N / inch. The measurement result of the electrolyte solution strength retention K of the measurement sample of Comparative Example 2 was K = 10% or less. After the measurement of the electrolyte strength retention, the lead-out portion of the electrode lead member and the sealant layer caused a peeling phenomenon (delamining) due to exposure to the electrolyte.

  The above results are summarized in Table 1. In Table 1, "adhesive strength between the lead-out portion of the electrode lead wire member and the sealant layer" is simply referred to as "adhesive strength".

Example 1 and Example 2 used a paint in which 3% by weight of an amorphous polymer having a hydroxyl group-containing polyvinyl alcohol skeleton (manufactured by Nippon Synthetic Chemical Co., Ltd.) and 1% by weight of chromium (III) fluoride were used. Then, since the thin film coating layer is laminated on the lead portion of the electrode lead wire member, the adhesive strength between the lead portion of the electrode lead member and the sealant layer is 40 N / inch or more. Further, the electrode lead wire member coated with a thin film coating layer between the sealant layer and the lead-out portion was resistant to the electrolyte of the lithium battery and had high pressure resistance.
On the other hand, Comparative Example 1 was a case where the thin film coating layer was not laminated on the electrode lead wire member, but the adhesive strength between the lead portion of the electrode lead wire member and the sealant layer was as high as 54 N / inch. In addition, the electrolyte strength retention rate K is 10% or less, and there is no electrolyte resistance.
Comparative Example 2 is a case in which the thin film coating layer was applied to the electrode lead wire member but was not dried by heating. The adhesive strength between the lead portion of the electrode lead wire member and the sealant layer was 46 N / inch, but the electrolyte strength retention rate K is 10% or less and there is no electrolyte resistance.

DESCRIPTION OF SYMBOLS 10 ... Laminated body for battery exterior, 11 ... Base layer, 12 ... Aluminum foil, 13 ... Resin film, 15, 16 ... Adhesive layer, 17 ... Lithium ion battery, 18 ... Electrode lead wire member, 19 ... Side edge , 20 ... Battery outer container, 21 ... Lead-out part, 22 ... Thin film coating layer, 23 ... Sealant layer, 30 ... Battery mounting container, 35 ... Battery storage container.

Claims (2)

A method for producing an electrode lead wire member drawn from a non-aqueous battery storage container,
On the surface of the metal outlet, a corrosion-resistant thin-film coating layer and a sealant layer are sequentially laminated,
The thin film coating layer comprises a resin having a hydroxyl group-containing polyvinyl alcohol skeleton or a copolymer resin thereof, and a substance made of metal fluoride or a derivative thereof,
The thin film coating layer is formed on the surface of the lead-out portion by printing on a surface of the lead-out portion in a band-like pattern wider than the sealant layer, in a direction in which the sealant layer is stacked so as to intersect the longitudinal direction of the lead-out portion. Become
A method for producing an electrode lead wire member, characterized in that the thin film coating layer is heated and dried and crosslinked or made amorphous to make it water resistant.   The method according to claim 1, wherein the sealant layer is a maleic anhydride-modified polyolefin-based resin film or an epoxy functional group-modified polyolefin-based resin film.

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