JP2006326879A - Resin coated metal sheet, housing for electric cell equipped with resin coated metal sheet and electric cell equipped with housing - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a resin coated metal sheet capable of keeping the good adhesiveness of an adhesive and a metal sheet even after the elapse of a long time and capable of enhancing the adhesiveness with a resin product, a housing equipped with the resin coated metal sheet and an electric cell equipped with the housing. <P>SOLUTION: The resin coated metal sheet 10 is equipped with the substrate metal sheet 1 and the adhesive resin layers 2a and 2a formed on the outermost surface of at least one side of the substrate metal sheet 1. The adhesive resin layers 2a and 2a are based on a polypropylene resin and the thickness of each of the adhesive resin layers 2a and 2a is 15 μm or below. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a resin-coated metal plate, a battery casing provided with the resin-coated metal plate, and a battery including the casing, and particularly, a polyolefin-based resin casing suitably used for a nickel-metal hydride battery or the like. The present invention relates to a resin-coated metal plate that can suitably reinforce a body, a polyolefin resin casing provided with the metal plate, and a battery including the casing.

  In nickel-metal hydride batteries (hereinafter referred to as “Ni-MH batteries”) used in hybrid cars and the like, a housing made of polyolefin resin (especially polypropylene resin) has been widely used. ing. On the other hand, Ni-MH battery housings that are actively researched to reduce the size, weight, and output of resin housings have good heat dissipation and gas generated by electrolytic reaction. It is desirable to have a strength that can withstand stress caused by the above. In order to ensure such strength with only the resin, it is necessary to increase the thickness of the casing. However, if the casing is increased in thickness, it is difficult to reduce the size of the Ni-MH battery. Therefore, recently, development for practical use of a metal plate, particularly a casing made of a steel plate, has been carried out.

  Compared with a resin casing, the casing made of a steel sheet has advantages that it is thin and easily secures strength, and is excellent in shielding and releasing heat of gas generated by an electrolytic reaction. On the other hand, the following disadvantages are conceivable for a steel plate casing.

  First, when manufacturing the case with a steel plate, forming such as rib processing is required. However, such processing generally requires multi-stage press processing, which increases processing costs. Second, since the electrolytic solution of the Ni-MH battery is alkaline, it is possible to apply a normal zinc-based plated steel sheet or aluminum-based plated steel sheet that is easily corroded by the alkaline electrolytic solution to at least the surface that contacts the electrolytic solution. difficult. Therefore, it is necessary to go through a plating process that is not very common in the steel sheet manufacturing process such as offline Ni plating, which increases costs. Thirdly, if it is attempted to secure the above-mentioned strength only with a steel plate, even if the thickness is reduced as compared with the conventional case, the mass tends to increase and it is difficult to reduce the weight.

  Therefore, in order to solve these problems, a technique for manufacturing a casing by integral composite molding of resin and metal has been studied. For example, in Patent Document 1, a laminate of a thermoplastic resin film, or a coil original plate pre-coated with a thermoplastic resin, or a stamped and formed metal part punched out from a metal plate of a sheet original plate is mounted in a mold, and the laminate A technique related to a method for manufacturing an electronic device casing is disclosed, in which component parts such as ribs and bosses are integrally molded on a layer surface or a precoat layer surface with a thermoplastic resin formed by injection molding. According to this technology, it is possible to produce an electronic device casing made of composite molding of a metal plate and a thermoplastic resin by a highly productive method.

Patent Document 2 uses a thermosetting coating system containing a rust preventive agent in the primer layer and an adhesive composition composed of an epoxy ester resin, a resol type phenol resin, a carboxyl group-modified polypropylene, and the like. -Techniques relating to polypropylene film laminates are disclosed. According to this technique, a resin-coated metal plate having excellent adhesion processability and corrosion resistance is provided.
JP 2001-315162 A JP 63-1111049 A

  Here, the housing manufactured by integral composite molding of resin and metal plate has good adhesion between resin and metal plate not only immediately after manufacture but also after long-time use. It is hoped that Furthermore, for example, when the Ni-MH battery is used, water or electrolyte may come into contact with the casing, or the casing may be exposed to a high-temperature and high-humidity environment. It is desirable to ensure the sex.

  However, the technique disclosed in Patent Document 1 has a problem that the adhesion between the resin and the metal plate is likely to be lowered, and it is difficult to improve the durability of the electronic device. In the technique disclosed in Patent Document 2, the adhesive layer and the laminate film are bonded on the steel plate, and the adhesiveness between the laminate film and the resin product is not studied.

  Therefore, the present invention is a resin-coated metal that can maintain good adhesion between the adhesive and the metal plate even after a long time and can improve the adhesion with the resin product. It is an object to provide a plate, a battery casing provided with the resin-coated metal plate, and a battery including the casing.

  The present invention will be described below. In order to facilitate understanding of the present invention, reference numerals in the accompanying drawings are appended in parentheses, but the present invention is not limited to the illustrated embodiment.

  1st this invention is equipped with the adhesive resin layer (2a, 2a) provided with the base metal plate (1) and the adhesive resin layer (2a, 2a) formed in the outermost surface of at least one side of the said base metal plate (1). 2a) is a resin-coated metal plate (10) characterized in that the main component is a polypropylene resin and the thickness of the adhesive resin layer (2a, 2a) is 15 μm or less. To solve.

  Here, the form of the base metal plate (1) is not particularly limited as long as the base metal plate (1) has better rigidity, gas barrier property, and heat dissipation than the resin. As a specific example of the base metal plate (1), In addition to steel sheets such as cold-rolled steel sheets and surface-treated steel sheets, aluminum alloy sheets can be used. In addition, the phrase “having a polypropylene resin as a main component” is sometimes described as 50% by mass or more of a polypropylene resin (hereinafter referred to as “PP resin”) in the adhesive resin layer (2a, 2a). ) Is included. Furthermore, specific examples of substances other than the polypropylene resin that can be included in the adhesive resin layers (2a, 2a) include urethane resins and phenol resins. The resin-coated metal plate (10) according to the present invention can be suitably used particularly as a reinforcing material for a battery casing formed of PP resin or the like.

  The second aspect of the present invention includes a base metal plate (1) and an adhesive resin layer (2b, 2b) formed on the outermost surface of at least one side of the base metal plate (1). 2b) is mainly composed of a copolymer resin of a polypropylene resin and an epoxy resin, and the thickness of the adhesive resin layer (2b, 2b) is 15 μm or less. The above problem is solved by the metal plate (11).

  Here, the form of the base metal plate (1) is not particularly limited as long as the rigidity, gas barrier property and heat dissipation are superior to the resin. As a specific example of the base metal plate (1), In addition to steel sheets such as cold-rolled steel sheets and surface-treated steel sheets, aluminum alloy sheets can be used. In addition, “the main component is a copolymer resin of a polypropylene resin and an epoxy resin” means that the adhesive resin layer (2b, 2b) includes a total of copolymer resins of a polypropylene resin and an epoxy resin. It means that it is contained by 50 mass% or more. Furthermore, specific examples of substances other than the above-described resins that can be included in the adhesive resin layers (2b, 2b) include urethane resins and phenol resins. The resin-coated metal plate (11) according to the present invention can be suitably used particularly as a reinforcing material for a battery casing formed of PP resin or the like.

  Moreover, in the said 1st or 2nd this invention, it is preferable that the extender pigment (5, 5, ...) is disperse | distributed to the adhesive resin layer (2a, 2a, or 2b, 2b).

  Specific examples of extender pigments (5, 5,...) According to the present invention include silica and titania (titanium dioxide).

  Furthermore, in the first or second aspect of the present invention, the base metal plate (1) is preferably an alloyed hot-dip galvanized steel plate.

  In addition, in the first or second aspect of the present invention, a base treatment layer (3, 3) that does not contain hexavalent chromium is formed on at least one surface of the base metal plate (1). It is preferable that an adhesive resin layer (2a, 2a, or 2b, 2b) is formed on the surface of the layer (3, 3).

  Here, the form of the ground treatment layer (3, 3) according to the present invention is not particularly limited as long as it does not contain hexavalent chromium. Specific examples of the base treatment layers (3, 3) according to the present invention include a chromium-free chemical conversion treatment solution (for example, Surfcoat EC-2100 manufactured by Nippon Paint Co., Ltd., and hereinafter referred to as “EC2100”). ) And the like formed by chemical conversion treatment. Further, “the adhesive resin layer (2a, 2a, or 2b, 2b) is disposed on the surface of the base treatment layer (3, 3)” means that the adhesive resin layer (2a, 2a, or 2b, 2b). ) And the base metal plate (1) means that a ground treatment layer (3, 3) is disposed. Specific examples of the thickness of the base treatment layer (3, 3) according to the present invention include about several tens of nm to 1 μm.

  The third aspect of the present invention is an integral injection of a resin-coated metal plate (10, 11) according to the first or second aspect of the present invention and / or a molded product obtained by press molding the same and a polyolefin resin. The battery housing (100, 110), which is manufactured by molding, solves the above problem.

  Specific examples of the polyolefin resin according to the present invention include polypropylene. From the viewpoint of reducing the size and weight of the housing (100, 110), it is preferable to make the resin-coated metal plates (10, 11) as thin as possible. Specific examples of the thickness of the resin-coated metal plate (10, 11) according to the present invention include about 0.2 to 0.4 mm.

  4th this invention is equipped with the housing | casing (100,110) and electrolyte solution (50) concerning 3rd this invention, Electrolyte solution (50), the said resin-coated metal plate (10,11), and / or Or the said subject is solved by the battery (1000) characterized by arrange | positioning so that the molded article obtained by press-molding this may not contact at the time of the use.

  Specific examples of the electrolytic solution (50) provided in the battery (1000) according to the present invention include an alkaline electrolytic solution (50). Further, in the present invention, the “arrangement so as not to come into contact during use” means that after the battery (1000) is completed (including when the battery (1000) is used), the electrolytic solution (50) and the resin-coated metal plate (10 11), and / or is arranged in a form that does not come into contact with a molded product obtained by press molding. Furthermore, specific examples of the battery according to the present invention include a Ni-MH battery that is used in a hybrid vehicle and the like.

  According to 1st this invention, since the adhesive resin layer (2a, 2a) which has a polypropylene resin as a main component is formed in the surface of a base metal plate (1), the said adhesive resin layer (2a) 2a) and the base metal plate (1) can be maintained for a long time. Moreover, since the thickness of the adhesive resin layer (2a, 2a) is 15 μm or less, the resin can be suitably bonded to the PP resin product (30) or the like via the adhesive resin layer (2a, 2a). It becomes possible to provide a coated metal plate (10).

  According to 2nd this invention, the adhesive resin layer (2b, 2b) which has as a main component the copolymer resin of a polypropylene resin and an epoxy resin is formed in the surface of a base metal plate (1). Therefore, even if the base metal plate (1) is a steel plate, the adhesiveness between the steel plate (1) and the adhesive resin layers (2b, 2b) can be maintained for a long time via the epoxy resin. become. Moreover, since the thickness of the adhesive resin layers (2b, 2b) is 15 μm or less, it is possible to provide a resin-coated metal plate (11) that can be suitably bonded to a PP resin product (30) or the like. Become.

  In the first or second aspect of the present invention, if the extender pigment (5, 5,...) Is dispersed in the adhesive resin layer (2a, 2a, or 2b, 2b), the adhesive resin layer ( 2a, 2a or 2b, 2b) and the base metal plate (1) can be further improved in adhesion.

  Furthermore, in the first or second aspect of the present invention, if the base metal plate (1) is an alloyed hot-dip galvanized steel plate, the base metal plate (1) and the adhesive resin layer (2a, 2a, or 2b, It becomes possible to easily improve the adhesiveness with 2b).

  In addition, in the first or second aspect of the present invention, a base treatment layer containing no hexavalent chromium between the adhesive resin layer (2a, 2a, or 2b, 2b) and the base metal plate (1) ( If 3, 3) is formed, it becomes possible to provide the resin-coated metal plates (10, 11) that can reduce the environmental load.

  According to the third aspect of the present invention, the polyolefin resin is integrally injected on the adhesive resin layer (2a, 2a, or 2b, 2b) provided on the resin-coated metal plate (10, 11). By carrying out the molding, the polyolefin resin (30) and the base metal plate (1) can be thermally fused via the adhesive resin layer (2a, 2a, or 2b, 2b). Therefore, according to the third aspect of the present invention, it is possible to easily manufacture the casing (100, 110) in a form in which the resin-coated metal plates (10, 11) are bonded to the surface of the polyolefin resin (30). become.

  According to the fourth aspect of the present invention, the battery (1000) includes the housing (100, 110) reinforced by the resin-coated metal plates (10, 11). Therefore, even if the casing (100, 110) is thinned, it becomes possible to ensure rigidity against the pressure of the gas generated inside, and the metal has a heat dissipation property superior to that of the resin. Therefore, a battery (1000) including a housing (100, 110) having excellent heat dissipation can be obtained. In addition, in the battery of the present invention, the electrolytic solution and the resin-coated metal plate and / or the molded product obtained by press-molding the same are arranged so as not to come into contact with each other during use. It becomes possible to maintain the adhesiveness between the metal plate and the polyolefin resin for a long time. Therefore, according to the fourth aspect of the present invention, there is provided a battery (1000) which has excellent rigidity and heat dissipation, can be easily reduced in size, and can further improve durability. It becomes possible.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

1. Resin-Coated Metal Plate FIGS. 1A and 1B are cross-sectional views schematically showing a part of the resin-coated metal plate of the present invention according to the first and second embodiments. As shown in FIG. 1A, a resin-coated metal plate 10 according to the first embodiment includes a base metal plate 1 and an adhesive resin layer 2a formed on the outermost surfaces on both sides of the base metal plate 1. 2a, and base treatment layers 3 and 3 are formed on the surface of the base metal plate 1. In the resin-coated metal plate 10, the base metal plate provided with the adhesive resin layers 2 a and 2 a mainly composed of PP resin on both sides is the cold-rolled steel plate 1. For example, EC2100 is applied to the cold-rolled steel plate 1. The base treatment layers 3 and 3 are formed by a method such as baking. The base metal is subjected to a process such as applying and baking an adhesive resin in which extender pigments 5, 5,... Are dispersed on the surface of the base metal plate 1 on which the base treatment layers 3 and 3 are formed. The resin-coated metal plate 10 in which the adhesive resin layers 2a and 2a are disposed on both sides of the plate 1 is manufactured.
On the other hand, the resin-coated metal plate 11 according to the second embodiment is an adhesive mainly composed of a copolymer resin of PP resin and epoxy resin instead of the adhesive resin layers 2a and 2a according to the first embodiment. Except for the provision of the conductive resin layers 2b and 2b, it has the same configuration as that of the first embodiment (see FIG. 1B).

1.1. Base metal plate The form of the base metal plate 1 provided in the resin-coated metal plates 10 and 11 is superior in the rigidity, gas barrier property, and heat dissipation to the resin used for the conventional Ni-MH battery casing and the like. If it is, it will not specifically limit, As a specific example, an aluminum alloy plate etc. other than a cold-rolled steel plate (for example, low carbon steel, ultra-low carbon steel etc.), a plated steel plate, etc. can be mentioned. However, in corrosive environments where contact with alkaline electrolytes is a concern, steel sheets that are not galvanized (for example, Ni-plated steel sheets) are used from the standpoint of providing a base metal sheet with good corrosion resistance. It is preferable to do this. In an environment where corrosion resistance is not so required, a zinc-based plated steel sheet, an aluminum-based plated steel sheet, an aluminum alloy sheet, or the like can be used.
On the other hand, when using a plated steel plate as the base metal plate, it is preferable to use an galvannealed steel plate from the viewpoint of improving the adhesion between the base metal plate and the adhesive resin layer.

1.2. Ground treatment In the resin-coated metal plates 10 and 11 of the present invention, the ground metal plate 1 is grounded from the viewpoint of improving the adhesion between the base metal plate 1 and the adhesive resin layers 2a and 2a (or 2b and 2b). It is preferable that the treatment layers 3 and 3 are formed. The base treatment layers 3 and 3 can be formed by a general chemical conversion treatment method. Specific examples of the chemical conversion treatment method include conventional chromate treatment. However, from the viewpoint of reducing the environmental load, it is preferable to form the base treatment layers 3 and 3 using a chromium-free base treatment solution that does not contain hexavalent chromium or lead. Specific examples of the ground treatment liquid include EC2100 and Surfcoat NC-10 manufactured by Nippon Paint Co., Ltd.

1.3. Adhesive Resin Layer Adhesive resin layers 2a and 2a provided on the resin-coated metal plate 10 according to the first embodiment include PP resin as a main component. Therefore, according to the present invention, for example, the PP resin product and the resin-coated metal plate 10 are heat-sealed via the adhesive resin layers 2a and 2a, so that the PP resin product is coated with the present invention. The metal plate 10 can be reinforced.

  On the other hand, the adhesive resin layers 2b and 2b included in the resin-coated metal plate 11 according to the second embodiment include a copolymer resin of a PP resin and an epoxy resin as a main component. That is, since the adhesive resin layers 2b and 2b are also provided with a PP resin, even the resin-coated metal plate 11 according to the present embodiment can be firmly bonded to the PP resin product. Furthermore, the adhesive resin layers 2b and 2b according to the present embodiment are provided with an epoxy resin. Therefore, the PP resin product and the base metal plate 1 can be bonded more firmly. In addition, when bonding PP resin product and the resin coating metal plate concerning this invention, there exists a tendency for a steel plate to adhere less to PP resin products than an aluminum alloy plate etc. Therefore, in such a case, it is preferable to use the adhesive resin layers 2b and 2b according to the second embodiment from the viewpoint of easily improving the adhesiveness between the PP resin product and the resin-coated metal plate.

  In the present invention, the adhesive resin layers 2a and 2b are not particularly limited as long as the main component is a PP resin and a copolymer resin of a PP resin and an epoxy resin, respectively. As long as the adhesiveness is not lowered, other substances may be contained. Specific examples of the other substances include urethane resins and phenol resins.

  Further, in the resin-coated metal plates 10 and 11, when the resin-coated metal plates 10 and 11 are attached to a PP resin product or the like, stress concentrates and the adhesive resin layers 2a and 2b break. From the standpoint of preventing or the like, the thickness is set to 15 μm or less. The thickness of the adhesive resin layers 2a and 2b (hereinafter referred to as “adhesive thickness”) is not particularly limited as long as it is 15 μm or less, but the surface of the base metal plate is smooth. In some cases, it is preferable to make the thickness of the adhesive as thin as possible (for example, 0.5 μm or less). With such a thickness, it is possible to easily prevent breakage starting from the adhesive resin layers 2a and 2b. On the other hand, when the surface of the base metal plate is rough, it is preferable to make the thickness of the adhesive relatively thick (for example, about 10 μm). With such a thickness, the resin-coated metal plates 10 and 11 having good adhesion can be obtained.

  Further, in the resin-coated metal plates 10 and 11, extender pigments 5, 5,... Are preferably dispersed in the adhesive resin layers 2a, 2b. By setting it as this form, it becomes possible to improve the adhesiveness of adhesive resin layer 2a, 2b and the base metal plate 1. FIG. Specific examples of extender pigments 5, 5,... That can be used in the present invention include titania and silica. Among these, titania is preferably used. Moreover, when it is set as the form provided with extender pigment 5, 5, ..., the addition amount of the extender pigment is preferably 10 to 10% of the solid content of the total dry mass of the resin constituting the adhesive resin layer and the extender pigment. It is 50 mass%, More preferably, it is 15-30 mass%. As a specific example of the method for dispersing the extender pigments 5, 5,... In the adhesive resin layers 2a, 2b, in a PP resin dissolved in a solvent or a copolymer of a PP resin and an epoxy resin. Examples of the method include dispersion.

  In addition, in the said description, although the form in which the adhesive resin layer was formed in the both surfaces side of the base metal plate was described, the resin-coated metal plate of this invention is not limited to the said form, The base metal plate The form by which the adhesive resin layer is formed only in the single side | surface side may be sufficient. When the adhesive resin layer is formed only on one side of the base metal plate, the other side is preferably subjected to the same treatment as the base treatment or other chemical conversion treatment from the viewpoint of corrosion resistance.

  In the above description, the adhesive resin layers 2a and 2b are formed on the surface of the base metal plate 1 by applying and baking the adhesive resin in which the extender pigments 5, 5,... Are dispersed. The method for forming the adhesive resin layer is not limited to this method. For example, a method of forming an adhesive resin layer on one side or both sides of a base metal plate by pressure bonding a resin film formed of an adhesive resin constituting the adhesive resin layer and a base metal plate It is also possible to use.

2. Battery Housing FIGS. 2A and 2B are horizontal cross-sectional views schematically showing the battery housing of the present invention according to the first and second embodiments. As shown in FIGS. 2 (A) and 2 (B), the battery casing 100 (or 110) of the present invention includes a frame formed of a PP-based resin 30, and is formed on two opposing surfaces of the frame. The resin-coated metal plates 10 and 10 (or 11, 11) according to the present invention are provided. And this housing | casing 100 puts PP-type resin 30 of a molten state in the metal mold | die (not shown) provided with a pair of resin-coated metal plates 10 and 10 (or 11, 11) arrange | positioned at specific intervals. It is manufactured by extruding and integrally injection-molding the PP resin 30 and the resin-coated metal plate 10, 10 (or 11, 11). As described above, according to the present invention, the resin-coated metal plates 10 and 10 (or 11 and 11) are provided on the two opposing surfaces of the frame body formed of the PP resin, and thus no metal plate is provided. Rigidity, heat dissipation, and gas barrier properties can be improved compared to conventional battery casings.

3. Battery FIGS. 3A and 3B are schematic views showing an example of a battery of the present invention and a battery housing provided in the battery. 3A is an external view schematically showing a part of a stacked Ni-MH battery including the battery casing of the present invention, and FIG. 3B is shown in FIG. It is a horizontal sectional view which shows roughly the example of the form of the battery case of the present invention with which the battery shown is shown.

  As shown in FIG. 3A, the Ni-MH battery 1000 of the present invention includes a frame body 500 and housings 110a, 110a,..., And a housing 110a including battery cells inside the frame body 500. 110a are stacked in series. On the other hand, as shown in FIG. 3 (B), the casing 110a provided in the Ni-MH battery 1000 includes a frame body formed of the PP resin 30 and the resin-coated metal plates 11 and 11, and includes a PP system. A space surrounded by the resin is filled with an alkaline electrolyte 50. That is, the electrolytic solution 50 and the resin-coated metal plates 11 and 11 provided in the casing 110a according to the present invention are separated by the PP resin 30 and the space in the PP resin frame is filled with the electrolytic solution 50. Then, the electrolytic solution 50 and the resin-coated metal plates 11 and 11 do not contact each other.

  On the other hand, FIG. 4 schematically shows another example of the Ni-MH battery casing. The casing 900 shown in FIG. 4 is manufactured by integrally injection-molding the resin-coated metal plates 11 and 11 and the PP resin 30, and an electrolytic solution is formed in a space surrounded by the PP resin 30 and the resin coatings 11 and 11. 50 is filled. Thus, when the electrolytic solution 50 and the resin-coated metal plates 11 and 11 come into contact, the resin-coated metal plates 11 and 11 are corroded by the electrolytic solution 50, and the resin-coated metal plates 11 and 11 and the PP resin 30 There is a possibility that the adhesiveness of the resin may deteriorate. In view of this, the battery 1000 according to the present invention is provided with a casing 1000a that is arranged so that the electrolytic solution 50 and the resin-coated metal plates 11 and 11 are not in contact with each other, and provides a battery 1000 that can improve durability. Yes.

  In addition, the housing | casing 110a with which the battery of this invention is equipped is equipped with the resin coating metal plates 11 and 11 on the surface of PP-type resin 30. FIG. Therefore, it is possible to improve rigidity, gas barrier properties, and heat dissipation properties as compared with a conventional housing that does not include the resin-coated metal plates 11 and 11. In particular, in the case 110a, by disposing a resin-coated metal plate on the surface of the PP-based resin, the rigidity and gas barrier properties are improved while reducing the thickness of the case. Therefore, according to the present invention, it is possible to provide a Ni-MH battery that can be easily downsized without degrading performance.

  In the above description, the case of FIG. 3B is illustrated as the case provided in the battery of the present invention. However, the case according to the present invention is not limited to the form, and the electrolyte and Other forms may be used as long as they are arranged so as not to contact the resin-coated metal plate. FIG. 5 shows another example of the casing according to the present invention.

  The casing 200 shown in FIG. 5 also does not contact the electrolytic solution 50 and the resin-coated metal plates 11 and 11 after the electrolytic solution 50 is filled. Therefore, even if the battery of the present invention includes the casing 200 of the form, the durability can be improved.

As described above, in the battery according to the present invention, when the filling of the electrolytic solution into the space in the PP resin frame is completed, the electrolytic solution and the resin-coated metal plate do not come into contact with each other. When the space is filled, the electrolytic solution and the resin-coated metal plate may come into contact with each other. Therefore, when there is a concern about contact at the time of electrolyte solution filling, it is preferable to use a base metal plate having good corrosion resistance against the electrolyte solution. Specific examples of the base metal plate include Ni-plated steel plates and cold-rolled steel plates.
On the other hand, when contact at the time of electrolyte solution filling is not a concern, from the viewpoint of improving the adhesion with the PP resin, an alloyed hot-dip galvanized steel sheet is used as the base metal plate, and PP is used as the adhesive resin layer. It is preferable to use a resin mainly composed of a copolymer resin of an epoxy resin and an epoxy resin.

  Hereinafter, the present invention will be described in more detail by way of examples.

<Example 1>
1.1. Preparation of test piece [Pretreatment]
A cold-rolled steel plate (plate thickness: 0.7 mm, surface roughness: 0.6 to 2.0 μm) was subjected to chromium-free chemical conversion treatment (treatment liquid: EC2100) as a base treatment. As a treatment method, the above treatment liquid was applied to the surface of the cold-rolled steel plate by a bar coating method, and then heated and baked in a hot air oven so that the plate temperature was about 230 ° C. In addition, Si contained in the base treatment layer formed by the base treatment was 20 mg / m ² .

[Formation of adhesive resin layer]
Next, an adhesive resin layer was formed on the surface of the base treatment layer formed by the above treatment. As the adhesive resin, the following were used.

(1) SC483 (manufactured by Sony Chemical Corporation)
The main component is a polyolefin resin and a bisphenol A solid epoxy resin, and a urethane resin and a phenol resin are contained. In a solution in which SC483 is dissolved in a solvent containing toluene, 2-methyl-2-propanol, and cyclohexane, 10 to 15% by mass of polyolefin resin (including polypropylene resin), 12% by mass of bisphenol A type solid epoxy resin, 5 mass% or less urethane resin and 5 mass% or less phenol resin were contained.
(2) Unistor R300 (Mitsui Chemicals)
The main component is a ternary (propylene, ethylene, butene) random polypropylene resin (1% carboxylic acid modification). A solution in which Unistor R300 (hereinafter referred to as “R300”) was dissolved in a solvent containing toluene and methyl ethyl ketone contained 18% by mass of a ternary random polypropylene resin.
(3) SW2214 (manufactured by Sumitomo 3M Limited)
The main component is an epoxy resin.
In this example, a material obtained by adding titania (CR50 manufactured by Ishihara Sangyo Co., Ltd.) to the adhesive resin was also used. The amount of titania added was 20% of the total dry mass of the adhesive resin and titania.

  The adhesive resin (containing titania but not containing titania) was applied to the surface of the base treatment layer by the barcode method, and baked in a hot air oven so that the plate temperature was about 200 ° C. The thickness of the adhesive resin layer formed through this process was 10 μm for SC483, 7 μm for R300, and 10 μm for SW2214.

[Preparation of test specimen for evaluation]
The resin-coated metal plate produced by the above process was cut into a size of 80 mm × 25 mm. And as shown in FIG. 6, the adhesive resin layer surface of the said resin coating metal plate opposes through the polypropylene piece which cut out the commercially available polypropylene plate (made by Sumitomo Chemical Co., Ltd.) of thickness 1mm to 10 mm x 25 mm. What was arranged in this way was heated for 5 minutes at 200 ° C. in a hot press apparatus. Then, pressurization was performed for 3 minutes at a pressure of 2.94 MPa in a temperature environment of 200 ° C., and subsequently cooling while applying pressure of 2.94 MPa to obtain a test specimen for evaluation (see FIG. 6).
The following performances were investigated using the test specimens thus produced.

1.2. Performance survey 1) Adhesive strength (as is)
The shear strength of the test specimen for evaluation was measured by carrying out a shear tensile test using a tensile tester (Toyo Seiki Seisakusho "Strograph").
2) Boiling-resistant water After the test specimen for evaluation was immersed in boiling water for 6 hours, the shear strength of the test specimen for evaluation was measured by the same method as in 1) above.
The results are shown in Table 1.

表１において、接着強さの「そのまま」とは、沸騰水に浸漬させていない評価用試験片のせん断強さ（ＭＰａ）を、「耐沸騰水」とは、耐沸水性試験後における評価用試験片のせん断強さ（ＭＰａ）を、それぞれ意味している。なお、本試験では、同一形態の評価用試験片を２枚以上作製し、その一部を接着強さ試験に、残りを耐沸水性試験に使用した。

In Table 1, “As is” of the adhesive strength means the shear strength (MPa) of the test piece for evaluation not immersed in boiling water, and “Boiling water” means for evaluation after the boiling water resistance test. It means the shear strength (MPa) of the test piece. In this test, two or more test pieces of the same form were prepared, a part of which was used for the bond strength test and the rest was used for the boiling water resistance test.

  In the test piece (1-5) using SW2214 as the adhesive resin, the adhesive resin layer and the cold-rolled steel sheet were not bonded at all, and the shear strength was 0 MPa. On the other hand, in the test piece (1-1 to 1-4) using SC483 or R300 containing a polypropylene resin, the shear strength including the test piece used in the following Example 2 and Example 3 is low. It was 8.82 MPa or more. Especially, the test piece (1-1, 1-2) using SC483 containing a polypropylene resin and an epoxy resin is the test piece (1-3, 1-4) using R300 which does not contain an epoxy resin. The shear strength value was large and the adhesiveness was excellent regardless of whether or not the boiling water test was conducted. Moreover, from the value of boiling water resistance, the test piece (1-2, 1-4) to which titania is added is more resistant to boiling water than the test piece (1-1, 1-3) to which titania is not added. The value of the later shear strength was large, and it was confirmed to have good boiling water resistance.

<Example 2>
2.1. Preparation of test piece The cold-rolled steel sheet used in Example 1 was subjected to the same chromium-free chemical conversion treatment as in Example 1 to form a base treatment layer as a base treatment, and titania (CR50) was added to the base treatment layer. The resin-coated metal plate was produced by applying and baking SC483. Here, the addition amount of titania was 0 to 40% by mass with respect to the total dry mass of the resin and titania, and the coating, baking, and cooling conditions were the same as in Example 1. Moreover, the thickness of the adhesive resin layer formed on the cold-rolled steel sheet was set to two levels of 4 μm and 10 μm.
The resin-coated metal plate thus produced was cut into the same size as in Example 1, and an evaluation test piece having the same form as in Example 1 was produced. And the following performance was investigated using this test piece for evaluation.

2.2. Performance survey 1) Adhesive strength (as is)
The shear strength of the test specimen for evaluation was measured by conducting a shear tensile test using a tensile tester (“Strograph” manufactured by Toyo Seiki Seisakusho Co., Ltd.).
2) Boiling-resistant water After the test specimen for evaluation was immersed in boiling water for 6 hours, the shear strength of the test specimen for evaluation was measured by the same method as in 1) above.
The results are shown in Table 2.

  From Table 2, regardless of the thickness of the adhesive resin layer and the amount of titania added, the shear strength of the test piece for evaluation (as it was) for which the boiling water resistance test was not performed was almost constant. On the other hand, after the boiling water test, the test piece (2-5 to 2-8) having the adhesive resin layer thickness of 10 μm is the test piece (2-1 to 2-4) having the same thickness of 4 μm. In particular, the value of boiling water resistance of the test piece (2-6) including an adhesive resin layer having a thickness of 10 μm to which 20% by mass of titania was added was good. On the other hand, when a test piece (2-3, 2-4) having an adhesive resin layer with a thickness of 4 μm to which 30% by mass of titania is added is immersed in boiling water, the resin-coated metal plate peels from the polypropylene piece. did. This is presumably because the proportion of the extender pigment in the adhesive was large, and the adhesiveness of the adhesive necessary for bonding the housing and the steel sheet could not be ensured.

<Example 3>
3.1. Preparation of Specimen Hot-dip galvanized steel sheet (plate thickness 0.7 mm; hereinafter referred to as “GI”), alloyed hot-dip galvanized steel sheet (plate thickness 0.7 mm; hereinafter referred to as “GA”), In addition, the cold-rolled steel sheets used in Examples 1 and 2 were prepared as steel sheets that were subjected to the same chromium-free chemical conversion treatment as in Example 1 to form a base treatment layer, and steel sheets that were not subjected to chemical conversion treatment as the base treatment. did. And the adhesive resin layer (SC483 is 10 micrometers thickness, R300 is 7 micrometers thickness) which consists of said SC483 or R300 was formed in these steel plates. In addition, titania was added to SC483 like Example 1, and application | coating, baking, and cooling conditions were made the same as that of Example 1.
The resin-coated metal plate thus produced was cut into the same size as in Example 1, and an evaluation test piece having the same form as in Example 1 was produced. And the following performance was investigated using this test piece for evaluation.

3.2. Performance survey 1) Adhesive strength (as is)
The shear strength of the test specimen for evaluation was measured by carrying out a shear tensile test using a tensile tester (Toyo Seiki Seisakusho "Strograph").
2) Boiling-resistant water After the test specimen for evaluation was immersed in boiling water for 24 hours, the shear strength of the test specimen for evaluation was measured by the same method as in 1) above.
The results are shown in Table 3.

表３中の★印は、鋼板が破断したことを示している。

The asterisk in Table 3 indicates that the steel plate was broken.

  From Table 3, the test pieces (3-9 to 3-12) using GA as a base metal plate are the test pieces (3-1 to 3-4) and cold-rolled steel plates using GI as the base metal plate. It was confirmed that the adhesion strength (as it is m) and the value after the boiling water test were better than the test pieces (3-5 to 3-8). In addition, the test pieces (3-1, 3-2, 3-5, 3-6, 3-9, 3-10) on which the base metal plate was subjected to the base treatment were the test pieces (3- 3, 3-4, 3-7, 3-8, 3-11, 3-12) and better boiling water resistance. Therefore, it was confirmed that it is preferable to use a resin-coated metal plate that has undergone a base treatment.

It is sectional drawing which shows roughly the resin-coated metal plate of this invention concerning 1st Embodiment and 2nd Embodiment. It is a horizontal sectional view showing roughly the case of the present invention concerning the 1st embodiment and the 2nd embodiment. It is the schematic which shows the form example of the housing | casing with which the battery of this invention and the said battery are equipped. It is a horizontal sectional view showing an example of a form of a case roughly. It is a horizontal sectional view which shows roughly the example of the form of the case concerning the present invention. It is the schematic which shows the form of the test piece for evaluation.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Base metal plate 2a, 2b Adhesive resin layer 3 Base treatment layer 5 Extender pigment 10, 11 Resin coated metal plate 30 Frame (product made from PP resin)
100 housing 1000 battery (Ni-MH battery)

Claims (7)

A base metal plate and an adhesive resin layer formed on the outermost surface of at least one side of the base metal plate, the adhesive resin layer having a polypropylene resin as a main component, and the thickness of the adhesive resin layer A resin-coated metal plate characterized by having a thickness of 15 μm or less. A base metal plate and an adhesive resin layer formed on the outermost surface of at least one side of the base metal plate,
The resin-coated metal plate, wherein the adhesive resin layer is mainly composed of a copolymer resin of polypropylene resin and epoxy resin, and the thickness of the adhesive resin layer is 15 μm or less. 3. The resin-coated metal plate according to claim 1, wherein extender pigments are dispersed in the adhesive resin layer. The resin-coated metal plate according to any one of claims 1 to 3, wherein the base metal plate is an alloyed hot-dip galvanized steel plate. A base treatment layer not containing hexavalent chromium is formed on at least one surface of the base metal plate, and the adhesive resin layer is formed on the surface of the base treatment layer. Item 5. The resin-coated metal plate according to any one of Items 1 to 4. It is manufactured by integral injection molding of the resin-coated metal plate according to any one of claims 1 to 5 and / or a molded product obtained by press molding the same and a polyolefin resin. A battery housing. The housing according to claim 6 and an electrolytic solution, wherein the electrolytic solution and the resin-coated metal plate and / or a molded product obtained by press-molding the resin-coated metal plate are not in contact with each other during use. A battery characterized by being arranged.

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