KR101462047B1 - Electrode lead wire member for nonaqueous battery - Google Patents

Abstract

The present invention provides an electrode lead wire member for a non-aqueous electrolyte cell having improved corrosion resistance so that the life of a lithium ion battery is prolonged.
The present invention relates to an electrode lead wire member (18) drawn out from a storage container for a non-aqueous cell battery using a laminate film laminate having at least a metal foil and a first sealant layer made of a sealant resin film as a casing, Film coating layer 22 and a sealant resin film using the same kind of resin as the first sealant layer, and a thermal seal is applied to the first sealant layer, Wherein the thin film coating layer (22) has a width of at least 2 mm or more in the longitudinal direction of the extruded encapsulation portion, a width narrower than that of the second sealant layer (23) And the electrode lead wire member 18 is formed in a strip-like pattern.

Description

[0001] ELECTRODE LEAD WIRE MEMBER FOR NONAQUEOUS BATTERY [0002]

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

In recent years, with the rise of environmental problems worldwide, effective use of natural energy such as the spread of electric vehicles, wind power generation, and photovoltaic power generation has become a problem. Accordingly, in these technical fields, a secondary battery or a capacitor such as a lithium ion battery is attracting attention as a battery for storing electric energy. An external container for storing a lithium ion battery used in an electric vehicle or the like may be a flat bag manufactured by using a laminate for battery exterior lamination of an aluminum foil and a resin film, A molding container made by molding is used so that a thin and lightweight material is being produced.

However, the electrolyte of a lithium ion battery has a property of being weak to moisture and light. For this reason, a laminate for battery exterior lamination, which is laminated with a base resin film made of polyamide or polyester and an aluminum foil and is excellent in waterproof property and light shielding property, is used as an exterior material for a lithium ion battery.

In order to accommodate the lithium ion battery in the storage container manufactured using such battery external laminate, for example, as shown in Fig. 3 (a), a battery external laminate is used in advance to have the recess 31 A shape on the tray is formed by drawing or the like, and accessories such as a lithium ion battery (not shown) and an electrode 36 are accommodated in the concave portion 31 of the tray. 3 (b), the lid 33 made of a laminate for covering the battery is stacked from above to wrap the battery, and the flange portion 32 of the tray and the side edge portions 34 of the lid member 33 ) Is heat-sealed to seal the battery. The storage container 35 formed by the method of placing the battery on the concave portion 31 of such a tray can store the battery from above, so productivity is high.

In the case of the conventional small-sized lithium ion battery, the depth of the tray (hereinafter, the depth of the tray may be referred to as " drawing ") in the placement container 30 of the lithium ion battery shown in FIG. 5 to 6 mm. However, in recent years, there has been a demand for a storage container for a large-sized battery in applications such as electric vehicles. In order to manufacture a storage container for a large-sized battery, it is necessary to form a tray of a deeper drawing, and technical difficulties are increasing.

Further, when water penetrates into the interior of the lithium ion battery, the electrolytic solution is decomposed by moisture and a strong acid is generated. In this case, the strong acid generated from the inside of the laminate for battery exterior penetrates, and as a result, the aluminum foil is corroded by the strong acid and is deteriorated to cause leakage of the electrolytic solution, resulting in deterioration of battery performance, .

Japanese Patent Application Laid-Open No. 2000-357494

As a countermeasure for preventing corrosion of the surface layer of the aluminum foil or the electrode lead wire constituting the battery external laminate by strong acid, Patent Document 1 discloses a method for producing a chromium-treated film by performing chromate treatment on the surface of an aluminum foil However, chromate treatment is a problem from the standpoint of environmental countermeasures because chromium, which is a heavy metal, is used, and hexavalent chromium can not be used because it is a harmful substance that affects the human body. Therefore, a chromate treatment solution of trivalent chromium is used, or a treatment liquid containing a chromium trihydroxide compound, a chromic trivalent carbonate compound and a water-soluble resin, a treatment containing an aqueous solution of hydrofluoric acid, a chromic acid trivalent compound and a water- Liquid. In addition, there is a problem that the effect of improving the corrosion resistance is small in the chemical treatment other than the chromate treatment.

Further, in the conventional electrode lead wire member, the aluminum member, which is the electrode member of the positive electrode, of both electrodes of the positive electrode and the negative electrode is good in electrolytic solution resistance, but the copper plate which is the electrode member of the negative electrode is provided with nickel plating on the surface layer, The electrolytic solution is poor in electrolytic solution property.

An object of the present invention is to provide an electrode lead wire member for a non-aqueous battery having improved corrosion resistance so that the life of a lithium ion battery is extended.

The present invention relates to a storage container for a battery, characterized in that the outer surface of the lead-out portion of the electrode lead wire member at the junction of the laminate film laminate of the casing and the lead- And the coating layer is laminated to improve the corrosion resistance to the corrosive electrolytic solution. The thin film coating layer is composed of a resin having a skeleton of a polyvinyl alcohol containing a hydroxyl group or a copolymer resin thereof.

In order to solve the above problems, the present invention is an electrode lead wire member drawn out from a storage container for a non-aqueous cell battery using a laminate film laminate having at least a first sealant layer made of a metal foil and a sealant resin film as a sheathing material, And a second sealant layer made of a sealant resin film using the same kind of resin as the first sealant layer and thermally bonded to the first sealant layer is formed on the surface of the lead- And the thin film coating layer is formed in a band-like pattern with a width of at least 2 mm or more in the longitudinal direction of the lead-out encapsulation portion, a width narrower than or equal to or greater than that of the second sealant layer And an electrode lead wire member.

In addition, the thin film coating layer may be formed by a chemical treatment with a treatment liquid containing a chromium trihydroxide compound and a water-soluble resin, a chemical treatment with a treatment liquid containing a chromium trihydroxide compound and a chromium tri-chromate compound and a water-soluble resin, A chromate treatment, a phosphate treatment, a zirconium treatment, and a triazinethiol treatment with a treatment liquid containing a chromate carbonate compound and a water-soluble resin, desirable.

In addition, among the lead-out encapsulation portions, a portion connecting the lead-out encapsulation portion to the current collecting portion of the electrode body of the non-aqueous cell and a portion connecting the electrode lead-wire members drawn out from the plural non- , The thin film coating layer is not formed and a part of the surface of the lead-out encapsulating part is subjected to a chemical treatment with a treatment liquid containing a chromium trifluoride compound and a water-soluble resin, a chromium trihydroxide compound, a trivalent chromium compound, A chemical treatment with a treatment liquid containing a resin, a chemical treatment with a treatment liquid containing a hydrofluoric acid aqueous solution, a chromic triacid compound and a water-soluble resin, a chromate treatment, a phosphate treatment, a zirconium treatment and a triazinethiol treatment It is preferable that none of them is carried out.

Further, it is preferable that the thin film coating layer is made of a resin containing a hydroxyl group.

It is also preferable that the thin film coating layer comprises a resin having a skeleton of a polyvinyl alcohol containing a hydroxyl group or a copolymer resin thereof.

Also, as described above, it is preferable that the thin film coating layer is rendered water-resistant by being crosslinked or uncrystallized by heat treatment.

It is preferable that the second sealant layer is a polyolefin-based sealant resin film modified with maleic anhydride or a polyolefin-based sealant resin film modified with an epoxy functional group.

The thickness of the second sealant layer is not less than 50 μm and not more than 300 μm and the thickness of the thin film coating layer is in the range of 0.2 to 5.0 μm and the interlayer peel strength of the thin film coating layer and the second sealant layer stacked thereon is not less than JIS Measured by the peel measurement method A specified in C6471, and is preferably 10 N / inch or more.

Here, N / inch corresponds to N / 25.4 mm.

A part for joining the lead-out sealing part to the current collecting part of the electrode body inside the non-aqueous cell and a part for joining the electrode lead-wire member drawn out from the plural non-aqueous-system battery storage containers in series or in parallel are not subjected to chemical conversion treatment, Since the electrolyte membrane is not adhered, there is no electrolyte-resistant film on the interface to be bonded at the time of bonding by ultrasonic bonding, resistance welding, or contact connection using a screw or the like, bonding property is improved.

A thin film coating layer made of a resin having a polyvinyl alcohol skeleton containing a hydroxyl group or a copolymer resin thereof in the lead-out encapsulation portion of the electrode lead wire member is rendered water-resistant by being crosslinked or uncured by heat treatment, It is possible to inhibit the electrolytic solution from intruding from both end portions viewed in section.

If both end portions of the lead-out portion of the electrode lead wire member are pressed down and thinner than the center portion of the end face, the lead-out portion of the electrode lead wire member and the laminate film laminate are in close contact with each other, .

The thin film coating layer is formed on the electrode lead wire member cut out by one by covering the thin film coating layer to the cut surface of the electrode lead wire member by coating the thin film coating layer.

1 is a perspective view showing an example of a storage container for a battery.
2 is a schematic cross-sectional view showing an example of a laminate for a battery used in a battery housing container.
3 is a perspective view showing a process of storing a lithium ion battery in a storage container in order.
Fig. 4A is a perspective view showing an example of the electrode lead wire member according to the present invention, and Fig. 4B is a sectional view along the SS line in Fig. 4A.
5 is a perspective view showing a cross-sectional view of a portion of a second sealant layer showing another example of the electrode lead wire member according to the present invention.
6 is a plan view showing an example of the electrode lead wire member according to the present invention.

1 and 2, a description will be made of an example in which the electrode lead wire member according to the present invention is drawn out from a storage container for a lithium ion battery manufactured by using a battery external laminate.

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 manufactured by folding and stacking a laminate body 10 for battery exterior lamination.

Further, the three-sided side edge portion 19 of the battery exterior container 20 is formed as a bag-like shape by heat sealing. The electrode lead wire member 18 is drawn out from the battery outer container 20 as shown in Fig. 3 shows a storage method for a battery storage container of a lithium ion battery manufactured using the electrode lead wire member 18 according to the present invention.

2, the laminate 10 for a battery enclosure comprising a laminate film laminate is formed by laminating the base resin film 11, the aluminum foil 12 and the first sealant layer 13 on the adhesive layers 15, 16).

4A, the electrode lead wire member 18 is provided with a metal lead-out encapsulating portion 21, and on the surface of the lead encapsulating portion 21, the same material as the first sealant layer 13 A second sealant layer 23 made of a sealant resin film is laminated via a corrosion-resistant thin-film coating layer 22. The second sealant layer 23 is thermally bonded to the first sealant layer when the electrode lead wire member 18 and the battery exterior laminate 10 are bonded.

The lead-and-encapsulate portion 21 of the electrode lead wire member 18 has a portion connecting the lead-out portion to the current collecting portion of the electrode body in the battery and a portion connecting the electrode lead- Since no chemical conversion treatment is performed on the portion to be joined in parallel (chemical conversion unexposed portion 25) and no electrolyte film is attached, bonding by ultrasonic wave welding, resistance welding, At the time of joining by using the adhesive layer, there is no electrolyte-resistant coating on the interface to be bonded, and bonding property is improved. 4 (b), it is preferable that both end portions 24 viewed from the end face are pressed to be thinner than the central portion of the end face of the electrode lead wire member 18, as shown in Fig. 4 (b).

4A shows a state in which the width L in the longitudinal direction of the lead-out encapsulation portion in which the thin film coating layer 22 of corrosion resistance is formed is formed to be wider than the width of the second sealant layer 23 . The width L in the longitudinal direction of the lead-out encapsulating portion formed with the corrosion-resistant thin-film coating layer 22 is 2 mm or more, and in FIG. 5, a state is formed in which the width is narrower than the width of the second sealant layer 23 have. 5, a part of the second sealant layer 23 is cut out so that a part of the thin film coating layer 22 is exposed. In reality, however, the whole of the thin film coating layer 22 is covered with the second sealant layer 23, Lt; / RTI >

The corrosion-resistant thin-film coating layer 22 is formed by a chemical conversion treatment using a chromium trifluoride compound, a chemical treatment with a chromium trihydroxide compound and a trivalent chromium compound, a chemical treatment with a hydrofluoric acid aqueous solution and a trivalent chromium compound, , A phosphate treatment, a zirconium treatment, and a triazinethiol treatment is preferably carried out. As the surface treatment method of aluminum used in the lead-out encapsulating portion 21, there are a method of treating with a treating solution containing a chromium trihydroxide compound and a water-soluble resin, a chromate treatment containing a chromium tetrafluoride compound, a trivalent chromium compound and a water- A chemical treatment with a treatment liquid, a chemical treatment with a treatment liquid containing a hydrofluoric acid aqueous solution, a chromic acid trivalent compound and a water-soluble resin, a chromate treatment with a chromic acid salt or a solution mainly composed of a dichromate salt, Or a treatment with an aqueous solution of a bichromic acid, a phosphate treatment in which an aqueous solution (usually containing fluoride) containing phosphate is treated, a zirconium treatment in which a chromium-free treatment liquid containing zirconium and a water-soluble polymer is treated, a triazinethiol derivative Treatment of triazine thiol with a solution in water or an organic solvent It can be given. Two or more types of these conversion treatments may be performed. With these chemical conversion layers, it is possible to constitute a thin corrosion-resistant coating layer 22 on the surface of the lead-out encapsulation portion 21. As the water-soluble resin of the thin-film coating layer 22, a resin containing a hydroxyl group can be mentioned. As the trivalent chromium compound, chromium fluoride (III) can be mentioned. The above-mentioned trivalent chromium carbonate compound may be a compound (basic chromium carbonate (III)) in which trivalent chromium carbonate and trivalent chromium hydroxide are combined.

In the case where the lead sealant 21 of the electrode lead wire member 18 is made of aluminum, the thin film coating layer 22 is formed of a resin having a skeleton of polyvinyl alcohol containing a hydroxyl group or a thin film made of the copolymer resin It is preferable that the coating layer is crosslinked and further contains a substance which is made of a metal fluoride or a derivative thereof and which passivates the surface of aluminum. However, the corrosion resistance of the coating layer is improved even when the fluorinated metal or its derivative is not contained. The thin film coating layer 22 formed on the surface of the lead-out encapsulating portion 21 is rendered water-resistant by being crosslinked or uncured by heat treatment.

A thin film coating layer composed of a corrosion-resistant layer formed by a chemical conversion treatment layer and a resin having a skeleton of a polyvinyl alcohol containing a hydroxyl group or a thin film coating layer composed of the copolymer resin can be used in combination. In this case, after a chemical treatment is performed on the surface of a part of the metal lead-out encapsulating portion 21, a resin having a skeleton of polyvinyl alcohol containing a hydroxyl group on the converted layer or a thin film coating layer made of the copolymer resin It is possible.

In the case where the material of the lead sealant 21 of the electrode lead wire member 18 is a metal coated with a nickel plating on the copper plate, the thin film coating layer is subjected to a conversion treatment by a treatment liquid containing a chromium trifluoride compound and a water- , A chemical treatment with a treatment liquid containing a chromium tri-fluoride compound, a trivalent chromium compound and a water-soluble resin, a chemical treatment with a treatment liquid containing a hydrofluoric acid aqueous solution, a chromic tri-carbonate compound and a water-soluble resin, or a triazine thiol treatment , Or a resin having a polyvinyl alcohol skeleton containing a hydroxyl group or a thin film coating layer composed of the copolymer resin is crosslinked and a substance which is composed of a metal fluoride or a derivative thereof and passivates the metal surface Is preferably contained.

The thin film coating layer 22 is formed on the surface of the lead-out encapsulation portion 21 in a strip-like pattern by printing. 4 (b), when the end portions 24 viewed from the end face are pressed and the thickness is thinner than the central portion of the end surface, the lead-out end portions 21 of the electrode lead wire member 18, It is preferable that the thin film coating layer 22 is formed on all sides of the lead-out encapsulating portion 21 including the thin film coating layer 24. The thin film coating layer 22 is formed in a strip-like pattern with a width equal to or greater than the width of the second sealant layer 23. [ The outer side in the width direction of the thin film coating layer 22 is the untreated untreated portion 25 and the thin film coating layer 22 is not formed on the outer surface of the thin film coating layer 22, A chemical treatment with a treatment liquid containing a compound and a water-soluble resin, a chemical treatment with a treatment liquid containing a chromium tri-fluoride compound, a chromium tri-chromate compound and a water-soluble resin, a treatment with a fluoric acid aqueous solution and a trivalent chromium compound and a water- There is no chemical conversion treatment group consisting of a chemical treatment by a treatment solution, a chromate treatment, a phosphate treatment, a zirconium treatment, and a triazinethiol treatment.

In the lead-out encapsulation portion 21 of the electrode lead wire member 18, generally, an anode is an aluminum plate, and a cathode is a metal coated with a nickel plating on a copper plate. The lead sealant 21 of the electrode lead wire member 18 and the first sealant layer 10 of the laminate body 10 for a battery are laminated in order to facilitate thermal bonding with the aluminum laminate film used as the battery laminate body 10 13, a second sealant layer 23 made of the same sealant resin film as that of the first sealant layer 13 of the laminate for external battery 10 is formed in advance.

If the thin film coating layer 22 of corrosion resistance is not formed on the surface layer of the lead-out encapsulating portion 21 of the electrode lead wire member 18, The water and the electrolytic solution react with each other in the surface layer to generate hydrofluoric acid and corrodes the lead sealing portion 21 of the electrode lead wire member 18 to deteriorate the adhesion between the electrode lead wire member 18 and the battery laminate 10 have. Therefore, at least the surface layer on the battery side of the lead-out encapsulation portion 21 of the electrode lead wire member 18 is laminated with a thin film coating layer 22 made of a resin having a polyvinyl alcohol skeleton containing a hydroxyl group or its copolymer resin . It is necessary to laminate the thin film coating layer 22 on the entire outer peripheral portion of the end surface of the lead sealing portion 21 of the electrode lead wire member 18.

As a countermeasure for preventing the corrosion of the electrode lead wire member made of aluminum by the electrolytic solution, the chromate treatment is known and used in the prior art. Compared to aluminum electrode lead wire members, it is also known that the effect of chromate treatment is small in metal electrode lead wire members coated with nickel plating on copper plates. However, in the present invention, it has been found that the metal electrode lead wire member coated with nickel plating on the copper plate has an effect of electrolytic solution resistance. Therefore, the conventional chromate method may be different from the corrosion deterioration preventing mechanism.

The resin having a skeleton of a polyvinyl alcohol containing a hydroxyl group or a copolymer resin thereof is a resin obtained by saponifying a polymer of a vinyl ester monomer or a copolymer thereof. Examples of the vinyl ester monomer 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 unsaturated acids such as ethylene, propylene, alpha -olefins, acrylic acid, methacrylic acid and maleic anhydride, and vinyl halides such as vinyl chloride and vinylidene chloride. A commercially available product is G Polymer Resin (trade name) manufactured by Nippon Gosei Kagaku Co., Ltd.

The thin film coating layer 22 is formed by crosslinking a thin film coating layer composed of a resin having a skeleton of polyvinyl alcohol containing a hydroxyl group or a copolymer resin thereof and further comprising a metal fluoride or a derivative thereof, It is preferable to contain a substance to be ignited. The fluorinated metal or its derivative is a substance containing F ^- ions forming a fluoride of passive aluminum, and examples thereof include chromium fluoride, iron fluoride, zirconium fluoride, titanium fluoride, hafnium fluoride, zirconium hydrofluoric acid and salts thereof, And fluorides such as hydrofluoric acid and salts thereof.

In order to form the thin film coating layer 22 on the surface layer of the lead-out encapsulation portion 21 of the electrode lead wire member 18, an amorphous polymer having a skeleton of polyvinyl alcohol containing hydroxyl group (Nippon Gosei Gaga And 0.2 to 6 wt% of chromium (III) chloride, and 0.1 to 3 wt% of chromium (III) chloride to obtain a thickness of 0.2 to 5 mu m after drying, The thin film coating layer 22 can be formed by heating and drying in an oven and baking adhesion and crosslinking.

As described above, when the thin film coating layer 22 is laminated on the surface layer surface of the lead sealant 21 of the electrode lead wire member 18, the pressure resistance of the thin film coating layer 22 is high, The intrusion of moisture from the edge portion (side edge portion) of the lead sealing portion 21 of the electrode lead wire member 18 into the inside of the lithium ion battery can be suppressed even if the thickness of the propylene layer or the polyethylene layer is made thin The deterioration with time of the electrolytic solution of the lithium ion battery is reduced, so that the product life of the battery can be prolonged.

In addition, even when hydrofluoric acid is generated by a small amount of moisture entering the battery and electrolytic solution reacting with water to decompose the electrolytic solution, the electrolytic solution is decomposed by the electrolytic solution containing hydroxyl groups stacked on the surface layer surface of the lead- Since the thin film coating layer 22 made of a resin having a polyvinyl alcohol skeleton or a copolymer resin thereof has a small free volume, it has a high gas barrier property and diffuses to the outside along the second sealant layer 23, Even if hydrofluoric acid of the electrode lead wire member 18 comes into contact with the surface of the aluminum plate as the lead-out sealing portion 21 of the electrode lead wire member 18, the lead- 21 is prevented and the interlaminar bond strength between the lead sealing portion 21 of the electrode lead wire member 18 and the second sealant layer 23 is maintained to maintain the withstand voltage strength, Does not occur.

The thickness of the second sealant layer 23 to be bonded in advance is preferably 50 to 300 mu m, and most preferably 50 to 150 mu m in consideration of the waterproofness. When the thickness of the lead-out encapsulating portion 21 of the electrode lead wire member 18 is 200 탆 or more, there is a case in which a through hole is formed at the edge of the lead encapsulating portion 21 of the electrode lead wire member 18 and the electrolyte can not be sealed have. Here, by crushing the edge of the electrode lead wire member 18, the thickness of the second sealant layer 23 to be bonded in advance can be reduced.

The thickness of the thin film coating layer 22 made of a resin having a polyvinyl alcohol skeleton containing a hydroxyl group or a copolymer resin thereof is preferably 0.1 to 10 占 퐉, more preferably 0.2 to 5.0 占 퐉, and most preferably 0.5 to 3 占 퐉 to be. The thickness of the thin film coating layer 22 increases the moisture resistance and the adhesive strength.

The thin film coating layer 22 is applied to a necessary portion of the lead encapsulation portion 21 of the electrode lead wire member 18 by a printing method. As the printing method, it is possible to use a known printing method such as an ink jet method, a dispenser method, and a spray coat method. The printing method that can be used in the present invention is not limited to the surface layer of the front and back surfaces of the lead-out encapsulation portion 21 of the electrode lead wire member 18 but also the surface of the lead edge portion 18 of the electrode lead- An inkjet method and a dispenser method are preferable because it is necessary to print the ink. Particularly, in the case of the dispenser method, an experiment using an application head capable of printing with a narrow width of about 10 mm width was found to be the most suitable method. In addition, it is preferable to continuously form the thin film coating layer on the loop-shaped electrode lead wire member by the printing method in view of increasing the working efficiency. However, when the loop-shaped electrode lead wire member is cut by one electrode lead wire member, the thin film coating layer is not formed on the cut surface.

On the other hand, according to the method of applying the thin film coating layer to the electrode lead wire members cut out one by one, it is preferable that the thin film coating layer is formed on the cut surface of the electrode lead wire member.

The second sealant layer 23 that has been previously bonded to the lead sealing portion 21 of the electrode lead wire member 18 is made of the same kind of resin as the first sealant layer 13 of the laminate body 10 for battery external use A sealant resin film is used. As the sealant resin film using the same kind of resin used for the first sealant layer 13 and the second sealant layer 23, when a polypropylene resin is used which is generally used, a film of a maleic anhydride-modified propylene alone Alternatively, it may be a single film of polypropylene modified with a monomer having an epoxy functional group such as glycidyl methacrylate, or a single film obtained by kneading an epoxy resin and a polypropylene resin to be aligned, or a multilayer film of polypropylene and polypropylene. In the case of selecting a polyethylene-based resin, a polyethylene single-modified with a monomer having an epoxy functional group such as maleic anhydride-modified polyethylene or glycidyl methacrylate, or a single polyethylene modified with an epoxy resin and a polyethylene resin It may be a single film or a multilayer film of polyethylene and its copolymer. In this case, even if a copolymer of maleic anhydride or acrylic acid, polyethylene modified with glycidyl methacrylate or the like is used on the surface of the second sealant layer 23 in contact with the thin film coating layer 22 serving as an electrolyte solution layer desirable.

As shown in Fig. 6, the second sealant layer 23 may be laminated so as to extend over both the positive electrode and the negative electrode. Thereby, the electrode lead wire member in which the anode and the cathode are integrated can be obtained. Since the corrosion preventive effect of the thin film coating layer 22 is obtained for various metal plates such as an aluminum plate and a nickel plated copper plate, it is preferable to form the thin film coating layer 22 on both the lead-out encapsulation portions 21 of the positive electrode and the negative electrode Do.

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

Example

(How to measure)

Method of Measuring Bond Strength between Leaded-Out Encapsulation Portion of Electrode Lead Wire Member and Second Sealant Layer: Measured by a measuring method prescribed in JIS C6471 "Test method of copper clad laminate for flexible printed wiring board".

Method of measuring the electrolyte strength retention ratio: Using a laminate for battery external application, a 4-chamber bag having a size of 50 mm × 50 mm (heat seal width = 5 mm) was prepared, and a PC / DEC electrolytic solution containing LiPF _{6 in an amount} of 1 mol / , Pure water was added in an amount of 0.5 wt%, and 2 cc thereof was weighed, filled and packed. A thin film coating layer was printed on a part of the lead-out encapsulating portion of the electrode lead wire member in the dispenser manner and the electrode lead wire member in which the second sealant layer was laminated by heat sealing was placed on the thin film coating layer. After storage for a time, the interlaminar bond strength (k2) between the electrode lead wire member and the second sealant layer is measured.

Here, the interlaminar bond strength (k1) between the lead-out encapsulation portion of the electrode lead wire member and the polypropylene (PP) film as the second sealant layer before exposure to the electrolytic solution previously measured and the interlaminar bond strength (k2) was defined as the electrolyte strength retention ratio K = (k2 / k1) x 100 (%).

(Measuring device)

Measuring apparatus of adhesive strength: manufactured by Shimadzu Corporation, type: AUTOGRAPH AGS-100A tensile test apparatus

(Example 1)

As the lead-out encapsulating portion of the electrode lead wire member for a lithium battery, an aluminum piece having a thickness of 200 탆 and cut into a size of 50 mm wide × 60 mm long was used. 1 wt% of an amorphous polymer having a skeleton of polyvinyl alcohol containing hydroxyl groups (trade name: G Polymer resin, manufactured by Nippon Gosei Kagaku Co., Ltd.) and 1 wt% of chromium (III) chloride on the surface of the aluminum- Coated on both sides with a dispenser so as to have a thickness of 1 mu m after heat-drying using the dissolved aqueous solution, and a thin film coating layer having a width of 10 mm was laminated on the central portion in the longitudinal direction of the lead- Further, the resin was heated and dried in an oven at 200 deg. C, and simultaneously crosslinked to obtain an electrode lead wire member of Example 1. At this time, it was confirmed that not only the surface layer of the front and back surfaces of the lead-out encapsulation portion of the electrode lead wire member of Example 1, but also the thin film coating layer was coated on both end surfaces in the direction perpendicular to the longitudinal direction of the lead encapsulation portion of the electrode lead wire member.

Further, a single layer film of a maleic anhydride-modified polypropylene film (polypropylene series resin manufactured by Mitsui Chemicals, Inc., product name: Admae QE060) was laminated on the thin film coating layer of the lead-out encapsulation portion of the electrode lead wire member of Example 1, Thick film) was bonded on both sides by heat sealing. Further, an aluminum laminate film having a thickness of 120 占 퐉 and made of an aluminum foil (thickness 20 占 퐉) / maleic anhydride-modified polypropylene film (thickness 100 占 퐉) was heat sealed to manufacture a part of the battery storage container of Example 1 Respectively.

The test piece for measuring the bonding strength was cut out from a part of the battery storage container of Example 1 and taken out. The bonding strength between the aluminum laminate film and the lead-out sealing portion of the electrode lead wire member was measured and found to be 46 N / inch .

The electrolyte strength retention ratio K was measured for a portion of the cell storage container of Example 1, where K = 88%.

10 or 15 sheets of aluminum foil (20 mu m in thickness) were superimposed on one end portion in the longitudinal direction of the lead-and-encapsulate portion of the electrode lead wire member and bonded by ultrasonic waves (using an ultrasonic adapter manufactured by Branson) All were joined without problems.

(Example 2)

Nickel sulfamic acid plating was plated to a thickness of 2 to 5 占 퐉 on the surface of a copper plate piece having a thickness of 200 占 퐉 (50 mm in width × 60 mm in length) as a lead-out portion of an electrode lead wire member for a lithium battery. 1 wt% of an amorphous polymer having a skeleton of polyvinyl alcohol containing hydroxyl groups (trade name: G Polymer resin, manufactured by Nippon Gosei Kagaku Co., Ltd.) and 1 wt% of chromium fluoride (III) were placed in the nickel plated lead- % Dissolved solution in a thickness of 1 mu m by a dispenser, and a thin film coating layer having a width of 20 mm was laminated on the central portion in the longitudinal direction of the extruded encapsulation portion in a strip shape. Further, the resin was heated and dried in an oven at 200 캜, and the resin was baked and crosslinked to obtain an electrode lead wire member of Example 2.

On the thin film coating layer of the lead-out portion of 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 part of the battery storage container of Example 2.

The test piece for measuring the bonding strength was cut out from a part of the battery storage container of Example 2 and the bonding strength between the aluminum laminate film and the lead-out sealing portion of the electrode lead wire member was measured. As a result, an adhesive strength of 44 N / Respectively.

In addition, the electrolyte strength retention ratio K was measured for a part of the cell storage container of Example 2, and the result was K = 78%.

In addition, 10 or 15 copper foils (20 mu m in thickness) were superimposed on one end portion in the longitudinal direction of the lead-and-encapsulate portion of the electrode lead wire member and bonded by ultrasonic wave (using an ultrasonic adapter manufactured by Branson) It was joined without problems.

(Example 3)

A part of the electrode lead wire member and the battery housing container of Example 3 were obtained in the same manner as in Example 1 except that the thin film coating layers were laminated at a center portion in the longitudinal direction of the lead-out encapsulation portion with a width of 2 mm.

A test piece for measuring the bonding strength was cut out from a part of the battery storage container of Example 3 and taken out. The bonding strength between the aluminum laminate film and the lead-out sealing portion of the electrode lead wire member was measured. As a result, an adhesive strength of 48 N / Respectively.

Further, the electrolyte strength retention ratio K of the electrolyte storage container of Example 3 was measured to be K = 86%.

10 or 15 sheets of aluminum foil (20 mu m in thickness) were superimposed on one end portion in the longitudinal direction of the lead-and-encapsulate portion of the electrode lead wire member and bonded by ultrasonic wave (using an ultrasonic adapter manufactured by Branson) All were joined without problems.

(Comparative Example 1)

A part of the electrode lead wire member and the battery storage container of Comparative Example 1 were obtained in the same manner as in Example 1 except that the thin film coating layer was formed on the entire surface of the aluminum piece.

A test piece for measuring the bonding strength was cut out from a part of the battery storage container of this Comparative Example 1 and the bonding strength between the aluminum laminate film and the lead-out sealing portion of the electrode lead wire member was measured. As a result, an adhesive strength of 54 N / Respectively.

Further, the electrolyte strength retention ratio K of the electrolyte storage container of Comparative Example 1 was measured to be K = 76%.

Further, ten or fifteen sheets of aluminum foil (20 mu m in thickness) were superimposed on one end portion in the longitudinal direction of the lead-and-encapsulate portion of the electrode lead wire member and bonded by ultrasonic wave (using an ultrasonic adapter manufactured by Branson) There was no problem in the case of covering 10 sheets, but when 15 sheets were superimposed, it was peeled off at the interface between the aluminum piece and the aluminum foil, and it was found that the bonding was weak.

(Comparative Example 2)

A portion of the electrode lead wire member and the battery storage container of Comparative Example 2 were formed in the same manner as in Example 2 except that the thin film coating layer having a width of 20 mm was laminated on the central portion in the longitudinal direction of the lead- .

A test piece for measuring the bonding strength was cut out from a part of the battery storage container of Comparative Example 2 and taken out. The bonding strength between the aluminum laminate film and the lead-out sealing portion of the electrode lead wire member was measured. As a result, an adhesive strength of 46 N / Respectively.

In addition, the electrolyte strength retention ratio K was measured on a part of the battery storage container of Comparative Example 2, where K = 10% or less. The electrode lead wire member and the second sealant layer caused delamination.

10 or 15 sheets of aluminum foil (20 mu m in thickness) were superimposed on one end portion in the longitudinal direction of the lead-and-encapsulate portion of the electrode lead wire member and bonded by ultrasonic wave (using an ultrasonic adapter manufactured by Branson) All were joined without problems.

(Comparative Example 3)

A part of the electrode lead wire member and the battery storage container of Comparative Example 3 were obtained in the same manner as in Example 1, except that the thin film coating layers were laminated in the longitudinal center portion of the lead-out encapsulation portion with a width of 1 mm.

The test piece for measuring the bonding strength was cut out from a part of the battery storage container of Comparative Example 3 and taken out. The bonding strength between the aluminum laminate film and the lead-out sealing portion of the electrode lead wire member was measured. Respectively.

Further, the electrolyte strength retention ratio K of the battery storage container of Comparative Example 3 was measured to be K = 31%, and the resistance to the electrolyte solution was weak.

10 or 15 sheets of aluminum foil (20 mu m in thickness) were superimposed on one end portion in the longitudinal direction of the lead-and-encapsulate portion of the electrode lead wire member and bonded by ultrasonic wave (using an ultrasonic adapter manufactured by Branson) All were joined without problems.

Table 1 shows the above results.

Examples 1 to 3 were prepared by mixing 1 wt% of an amorphous polymer having a skeleton of a hydroxyl group-containing polyvinyl alcohol (trade name: G polymer resin, manufactured by Nippon Gosei Chemical Co., Ltd.) and 1 wt% of chromium (III) Is coated on the lead-out encapsulation portion of the electrode lead wire member by using the mixed aqueous solution to laminate the thin film coating layer. These thin film coating layers have a thickness of 1 mu m after heat-drying, and are formed to have a width of at least 2 mm or more in the longitudinal direction of the lead-out encapsulation portion. The bonding strength between the electrode lead wire member and the second sealant layer was 40 N / inch or more. Further, the lead-encapsulation portion of the electrode lead wire member in which the thin film coating layer was formed under the second sealant layer had the electrolyte strength retention ratio K of 78% or more, and the electrolyte solution of the lithium battery also had corrosion resistance.

In Example 3, the thin-film coating layer was laminated at a central portion in the longitudinal direction of the lead-out encapsulation portion with a width of 2 mm. The bonding strength between the lead-out encapsulation portion of the electrode lead wire member and the second sealant layer was 48 N / inch, The retention ratio K was as high as 86% and had corrosion resistance to the electrolytic solution.

On the other hand, in Comparative Example 1, the thin film coating layer was formed on the entire surface of the aluminum lead piece in the lead-out encapsulation portion of the electrode lead wire member, and the adhesion strength between the lead encapsulation portion of the electrode lead wire member and the second sealant layer was as high as 54 N / inch And the electrolytic solution strength retention ratio K was 76%. However, there was a problem that bonding with the aluminum foil was weak.

In Comparative Example 2, the thin-film coating layer was applied to the lead-out encapsulation portion of the electrode lead wire member, but not heated and dried. The bonding strength between the lead-out encapsulation portion of the electrode lead wire member and the second sealant layer was 46 N / inch, The retention rate K was 10% or less, and there was no corrosion resistance to the electrolytic solution.

In Comparative Example 3, the thin-film coating layer was laminated at a central portion in the longitudinal direction of the lead-out encapsulation portion with a width of 1 mm, and the bonding strength between the lead-out encapsulation portion of the electrode lead wire member and the second sealant layer was 52 N / inch, K was as small as 31%, and there was no corrosion resistance against the electrolytic solution.

In view of the above, it has been found that it is necessary that the thin film coating layer is an electrode lead wire member formed in a strip-like pattern with a width of at least 2 mm or more in the longitudinal direction of the lead-out encapsulation portion. The electrode lead wire member according to the present invention can be used as an electrode lead wire member for a non-aqueous battery using an organic electrolyte for an electrolyte such as a lithium ion battery or an electric double layer capacitor (hereinafter referred to as " capacitor ") as a secondary battery.

L ... The width of thin film coating layer, 10 ... Laminate film laminate (laminate for battery exterior laminate), 11 ... Base resin film, 12 ... Aluminum foil, 13 ... The first sealant layer, 15,16 ... Adhesive layer, 17 ... Lithium ion battery, 18 ... Electrode lead wire member, 19 ... Side edge, 20 ... Battery external container, 21 ... The extraction bag portion 22 ... Thin film coating layer, 23 ... Second sealant layer, 24 ... Both end portions seen from the cross section of the lead-out encapsulating portion, 25 ... Untreated part of Mars, 30 ... Battery container, 35 ... Storage compartment for batteries.

Claims (8)

An electrode lead wire member drawn out from a storage container for a non-aqueous cell battery using a laminate film laminate having at least a metal foil and a first sealant layer made of a sealant resin film as a sheathing material,
And a second sealant made of a sealant resin film using the same kind of resin as the first sealant layer and thermally adhered to the first sealant layer is provided on the surface of the lead- Wherein the thin film coating layer is at least 2 mm wide or more in the longitudinal direction of the lead-out encapsulation portion, and the second sealant layer is formed by laminating the first sealant layer and the second sealant layer in this order, Wherein the electrode lead-wire member is formed in a band-like pattern with a width narrower than or equal to the width of the electrode. The method according to claim 1,
Wherein the thin film coating layer is formed by a chemical treatment with a treatment liquid containing a chromium trihydroxide compound and a water-soluble resin, a chemical treatment with a treatment liquid containing a chromium trihydroxide compound, a chromium tri-chromate compound and a water-soluble resin, Characterized in that the chemical conversion layer comprises at least one selected from the group consisting of a chemical conversion treatment consisting of a chemical treatment with a treatment liquid containing a chromium compound and a water-soluble resin, a chromate treatment, a phosphate treatment, a zirconium treatment and a triazine thiol treatment Electrode lead wire member. 3. The method according to claim 1 or 2,
A portion of the lead-out encapsulation portion, to which the lead-out encapsulation portion is connected to the current collecting portion of the electrode body of the non-aqueous cell, and a portion to which the electrode lead- A thin film coating layer is not formed and a part of the surface of the lead-out encapsulating part is subjected to a chemical treatment by a treatment liquid containing a chromium trihydrofluoride compound and a water-soluble resin, a chromium trihydroxide compound, a trivalent chromium compound and a water- Any of the chemical conversion treatment groups consisting of a chemical treatment by a treatment solution, a chemical treatment by a treatment solution containing a hydrofluoric acid aqueous solution, a chromic trivalent compound and a water-soluble resin, a chromate treatment, a phosphate treatment, a zirconium treatment, and a triazinethiol treatment And the electrode lead wire member is not carried out. 3. The method according to claim 1 or 2,
Wherein the thin film coating layer is made of a resin containing a hydroxyl group. 3. The method according to claim 1 or 2,
Wherein the thin film coating layer comprises a resin having a skeleton of polyvinyl alcohol containing a hydroxyl group or a copolymer resin thereof. delete 3. The method according to claim 1 or 2,
Wherein the second sealant layer is a polyolefin-based sealant resin film modified with maleic anhydride or a polyolefin-based sealant resin film modified with an epoxy functional group. 3. The method according to claim 1 or 2,
Wherein the thickness of the second sealant layer is 50 占 퐉 or more and 300 占 퐉 or less and the thickness of the thin film coating layer is 0.2 to 5.0 占 퐉 and the interlayer peel strength between the thin film coating layer and the second sealant layer stacked thereon is JIS C6471 Wherein the electrode lead wire member is measured by the peeling measurement method A specified in the above item (1).

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