Blade type battery and manufacturing method therefor

Abstract

Provided are: a blade type battery comprising a lid body structure that is simple with a small number of components and is capable of surely preventing leakage of an electrolytic solution and ingress of moisture or the like from the outside; and a manufacturing method therefor.　A sealed blade-type battery 17 includes a lid body 1 provided so as to close an opening of a battery container 16. The lid body 1 comprises: a terminal member 2 corresponding to a positive electrode and a negative electrode; a sealing plate 3 having an attachment hole 5 for attaching the terminal member 2; and a sealing material 4 for attaching the terminal member 2 to the attachment hole 5 of the sealing plate 3 and sealing the terminal member. The sealing material 4 contains a polyarylene sulfide resin as a thermoplastic resin and contains an acrylic ester. The terminal member 2 has a hydroxyl group-containing coating film on the outer peripheral surface thereof. The sealing plate has a hydroxyl group-containing coating film on an inner wall surface of the attachment hole. The terminal member 2 is sealed in the attachment hole 5 of the sealing plate 3 with the sealing material 4 interposed therebetween.

Description

Blade-type battery and method for manufacturing the same

[0001] The present invention relates to a blade-type battery and a method for manufacturing the same. The present invention relates to a sealed blade-type battery having a simple structure and excellent sealing properties, and a method for manufacturing the same.

[0002] Rechargeable batteries such as lithium-ion batteries, which can be repeatedly charged and discharged, are widely used in various fields, including mobile devices such as mobile phones and laptops, transport vehicles such as automobiles and aircraft, and facilities such as factories, schools, and hospitals.

[0003] These rechargeable batteries generally have a structure in which an electrode body, comprising a positive electrode and a negative electrode, is housed in a battery container with an opening and sealed by a lid. The lid is provided with mounting holes corresponding to the positive and negative electrodes. Terminal members are inserted through the mounting holes and connected to lead wires drawn out from the electrode body inside the battery container, thereby enabling electrical conductivity between the inside and outside of the battery.

[0004] However, when a flammable liquid is used as the electrolyte in a secondary battery, the battery cover requires a highly sealing structure that can prevent leakage.

[0005] For example, Patent Document 1 discloses a battery comprising a case having terminal lead-out holes, electrode terminals penetrating the terminal lead-out holes, and a sealing member provided between the case and the electrode terminals, wherein the base portion of the electrode terminals has a deformation suppression portion having a contact wall that contacts the outer peripheral end surface of the flat plate portion of the sealing member (Claims).

[0006] Patent Document 2 discloses a lid structure in which a hole is formed in a metal lid, a thermoplastic resin seal gasket having a cylindrical portion is inserted from the back side of the lid, and a metal external terminal is inserted into the cylindrical portion of the seal gasket, and the inner surface of the hole in the lid and the outer surface of the cylindrical portion of the seal gasket, and the inner surface of the cylindrical portion of the seal gasket and the outer surface of the external terminal are joined by laser processing (claims).

[0007] Patent Document 3 discloses a lid for a sealed battery, comprising a terminal member, a sealing plate having mounting holes for attaching the terminal member, and a sealing material containing a thermoplastic resin and an inorganic filler, wherein the terminal member is attached to the mounting holes with the sealing material joined to it (claims). Furthermore, Patent Document 3 states that the thermoplastic resin of the sealing material includes a polyarylene sulfide resin (claims), that the sealing material is joined to the sealing plate and the terminal member by an anchoring effect at the surfaces in contact, that laser treatment, sandblasting, etc. are given as examples of surface roughening treatment for the anchoring effect (paragraph

[0034] ), and that the sealing material can be molded integrally with the sealing plate and the terminal member by injection molding (paragraph

[0035] ).

[0008] Japanese Patent Publication No. 2021-028888, Japanese Patent Publication No. 2012-33339, Japanese Patent Publication No. 2022-103899

[0009] As mentioned above, sealed batteries such as lithium-ion secondary batteries require reliable prevention of electrolyte leakage, and various lid structures have been considered for this purpose.

[0010] However, lid structures like those in Patent Documents 1 and 2 above have a large number of parts and increase the number of manufacturing steps, resulting in reduced production efficiency.

[0011] Although the lid described in Patent Document 3 above has a relatively simple structure, the presence of inorganic fillers contained in the sealing material may cause voids to form on the contact surface between the terminal member and the sealing material, or between the sealing plate and the sealing material. If moisture originating from air is present in such voids, that moisture may cause the electrolyte in the electrolyte solution (for example, LiPF4) to be affected. ６ There is a risk that toxic hydrogen fluoride may be generated from fluorine-containing compounds such as these.

[0012] The object of the present invention is to provide a blade-type battery and a method for manufacturing the same, which have a small number of parts, a simple structure, and a lid structure that can reliably prevent electrolyte leakage and the intrusion of moisture from the outside.

[0013] The inventors of the present invention conducted studies to solve the above problems. As a result, they found that by selecting a combination of coating components applied to the outer surface of the terminal member and the inner wall surface of the mounting hole of the sealing plate, and components contained in the sealing material, a blade-type battery with a simple structure and excellent sealing performance can be obtained, and thus completed the present invention. Specifically, the present invention encompasses the following embodiments (1) to (9). In this specification, the expression "~" includes the numerical values ​​at both ends. That is, "X~Y" is synonymous with "X or more and Y or less".

[0014] (1) A sealed blade-type battery comprising a battery container having openings at both ends, an electrode body having a positive electrode and a negative electrode housed in the battery container, and a lid provided to close the openings, wherein the lid comprises terminal members corresponding to the positive electrode and the negative electrode, a sealing plate having mounting holes for attaching the terminal members, and a sealing material for attaching and sealing the terminal members in the mounting holes of the sealing plate, the sealing material comprising a polyarylene sulfide resin as a thermoplastic resin and also comprising an acrylic acid ester, the terminal members having a hydroxyl group-containing film on their outer circumferential surface, the sealing plate having a hydroxyl group-containing film on the inner wall surface of the mounting holes, and the terminal members being sealed in the mounting holes of the sealing plate via the sealing material.

[0015] (2) The blade-type battery according to (1) above, wherein the sealing material contains 0.1% by mass or more and 20% by mass or less of acrylic acid ester.

[0016] (3) The blade-type battery according to (1) above, wherein the acrylic acid ester is one or more selected from the group consisting of methyl acrylate, ethyl acrylate, butyl acrylate, 2-dimethylaminoethyl acrylate, and 2-hydroxyethyl acrylate.

[0017] (4) The blade-type battery according to (1) above, wherein the hydroxyl group-containing film has an oxygen content of 0.1% by mass or more and 50% by mass or less as measured by EPMA in the surface layer up to a depth of 3 μm from the outermost surface.

[0018] (5) The blade-type battery according to (1) above, wherein the sealing material contains one or more polyolefins selected from the group consisting of polyethylene and polypropylene.

[0019] (6) The blade-type battery according to (5) above, wherein the sealing material contains 0.1% by mass or more and 40% by mass or less of the polyolefin.

[0020] (7) The blade-type battery according to (1) above, wherein the sealing material contains polydimethylsiloxane as an additive.

[0021] (8) The blade-type battery according to (1) above, wherein the terminal member of the lid provided at one end of the battery container corresponds to the positive electrode, and the terminal member of the lid provided at the other end of the battery container corresponds to the negative electrode.

[0022] (9) A method for manufacturing a blade-type battery as described in any of (1) to (8) above, comprising: arranging the sealing plate and the terminal member constituting the lid in a mold of an injection molding apparatus, and arranging them with a gap between the mounting hole of the sealing plate and the terminal member; injecting a resin for forming the sealing material into the mold; and removing the lid, which is sealed by the sealing material with the terminal member joined to the mounting hole of the sealing plate, from the mold.

[0023] According to the present invention, it is possible to provide a sealed blade-type battery that has a small number of parts, a simple structure, and a lid structure that can reliably prevent electrolyte leakage and the intrusion of moisture from the outside. According to the present invention, such a blade-type battery can be manufactured efficiently.

[0024] This is a schematic plan view illustrating the shape of the lid in the blade-type battery according to this embodiment. This is a schematic cross-sectional view of the lid, showing a cross section perpendicular to the line X-X in Figure 1. This is a schematic perspective view illustrating the shape of the lid shown in Figures 1 and 2. This is a schematic plan view illustrating the shape of another lid in the blade-type battery according to this embodiment. This is a schematic cross-sectional view of the lid, showing a cross section perpendicular to the line Y-Y in Figure 4. This is a schematic cross-sectional view showing a cross section of the region in Figure 2 where the sealing plate, terminal member and sealing material are joined. This is a schematic diagram illustrating the entire blade-type battery according to this embodiment. This is a schematic diagram illustrating the process for manufacturing the lid of the blade-type battery according to this embodiment. This is a schematic diagram illustrating the process following the process shown in Figure 8. This is a schematic diagram illustrating the process following the process shown in Figure 9. This is a plan view of the test lid used in the evaluation test of the embodiment. This is a cross-sectional view perpendicular to the line A-A in Figure 11. This is a cross-sectional view perpendicular to the line B-B in Figure 11. This is a cross-sectional view of the region in Figure 11 where the sealing plate, terminal member and sealing material are joined. This is a diagram illustrating the shape of the test cover shown in Figure 11. This is a top view of the sealing plate used in the test cover shown in Figure 11. This is a bottom view of the sealing plate used in the test cover shown in Figure 11. This is a plan view of the terminal member used in the test cover shown in Figure 11. This is a front view of the terminal member used in the test cover shown in Figure 11. This is a schematic plan view showing an example of a cover according to another embodiment. This is a schematic cross-sectional view showing a cross section of Figure 20. This is a schematic diagram illustrating the process for manufacturing the cover shown in Figure 20. This is a schematic diagram illustrating the process following the process shown in Figure 22. This is a schematic diagram illustrating the process following the process shown in Figure 23. This is a schematic plan view showing an example of a cover according to another embodiment. This is a schematic plan view showing an example of a cover according to another embodiment.

[0025] The following describes embodiments of the present invention (hereinafter referred to as "these embodiments"). The present invention is not limited to the following embodiments, and various modifications are possible without altering the essence of the invention.

[0026] (Blade-type battery) The blade-type battery according to this embodiment is a sealed blade-type battery comprising a battery container having openings at both ends, an electrode body having a positive electrode and a negative electrode housed in the battery container, and a lid provided to close the openings, wherein the lid comprises terminal members corresponding to the positive electrode and the negative electrode, a sealing plate having mounting holes for attaching the terminal members, and a sealing material for attaching and sealing the terminal members in the mounting holes of the sealing plate, wherein the sealing material contains a polyarylene sulfide resin as a thermoplastic resin and also contains an acrylic acid ester, the terminal members have a hydroxyl group-containing film on their outer circumferential surface, the sealing plate has a hydroxyl group-containing film on the inner wall surface of the mounting holes, and the terminal members are sealed in the mounting holes of the sealing plate via the sealing material.

[0027] A blade-type battery refers to a battery having a flat, rectangular shape as shown in Figure 7 below. The battery container is a container that houses an electrode body having a positive electrode and a negative electrode, and has openings at both ends. The blade-type battery according to this embodiment has a sealed structure in which a lid is provided to close the above openings. The terminal members of the lid and the electrode body inside the battery container are electrically connected via lead wires.

[0028] (Cover) The cover of the blade-type battery according to this embodiment comprises terminal members corresponding to the positive electrode and the negative electrode, a sealing plate having mounting holes for attaching the terminal members, and a sealing material for attaching and sealing the terminal members in the mounting holes of the sealing plate. The cover can be arranged such that the terminal member of the cover provided at one end of the battery container corresponds to the positive electrode, and the terminal member of the cover provided at the other end of the battery container corresponds to the negative electrode.

[0029] Figures 1 to 3 show an example illustrating the cover of a blade-type battery according to this embodiment. Figure 1 is a schematic plan view showing the shape of the cover, Figure 2 is a schematic cross-sectional view of the cover showing a cross section perpendicular to the line X-X in Figure 1, and Figure 3 is a schematic perspective view showing the shape of the cover shown in Figures 1 and 2.

[0030] As shown in Figures 1 to 3, the lid body 1 includes a terminal member 2, a sealing plate 3 having a mounting hole 5, and a sealing material 4 for attaching the terminal member 2 to the mounting hole 5. As the terminal member, an aluminum electrode, a copper electrode, or the like can be used. As the sealing plate, an aluminum base material or the like can be used. The lid body 1 has an explosion-proof valve 8 provided at an arbitrary position separate from the regions of the terminal member 2 and the sealing material 4. The explosion-proof valve 8 is a member having a safety function for releasing the internal pressure and reducing the pressure when the internal pressure of the battery container rises beyond a set level.

[0031] Figures 4 and 5 show an example for explaining another lid body in the blade-type battery according to the present embodiment, Figure 4 is a plan view schematically showing the form of the lid body, and Figure 5 is a cross-sectional view schematically showing the cross section of the lid body perpendicular to the Y-Y line in Figure 4.

[0032] As shown in Figures 4 and 5, the lid body 10, similarly to the lid body 1 in Figures 1 to 3, includes a terminal member 2, a sealing plate 3 having a mounting hole 5, and a sealing material 4 for attaching the terminal member 2 to the mounting hole 5. The lid body 10 has a liquid injection hole 11 provided at an arbitrary position separate from the regions of the terminal member 2 and the sealing material 4. The liquid injection hole 11 is a hole for injecting an electrolytic solution into the battery container. A sealing plug (not shown) is attached to the liquid injection hole so that the electrolytic solution in the battery container does not leak to the outside.

[0033] (Terminal Member) The terminal member according to this embodiment only needs to cover the mounting hole, and its shape and size are not particularly limited. For example, as shown in the plan views of Figures 1 and 4, a terminal member having a contour consisting of two straight sections 6 and two curved sections 7 may be used. Such a contour shape is sometimes called "oval" and is similar in shape to the track (running surface) of an athletics stadium. The two straight sections 6 are spaced apart from each other and run almost parallel to each other in the longitudinal direction of the cover. The curved section 7 is arranged to connect with the straight sections 6. When the contour is viewed clockwise in Figures 1 and 4, it shows a configuration in which the first straight section 6A, the first curved section 7A, the second straight section 6B, and the second curved section 7B are connected in that order. The curved sections may draw curves with arbitrarily changed radii of curvature. The straight sections can be selected from a range of 5 to 100 mm, and the radii of curvature of the curved sections can be selected from a range of 0.1 to 30 mm. Furthermore, the terminal member is preferably shaped or sized to correspond to the mounting hole, and a range of 10 to 90% of the vertical or horizontal length of the mounting hole can be selected.

[0034] The terminal member can be selected to have any shape and dimensions in the thickness direction. For example, as shown in the cross-sectional views of Figures 2 and 5, it may have a substantially flat thickness. The thickness can be selected in the range of 0.1 to 100 mm. In this specification, when indicating the shape or dimensions of the cover and terminal member, the longitudinal direction is sometimes referred to as the "lateral direction," and the direction different from the lateral direction is sometimes referred to as the "vertical direction." The terminal member should be positioned so as not to overlap with the location where the explosion-proof valve or liquid injection hole is installed. The length of the terminal member should be within the range of the length of the cover. For example, the lateral length of the terminal member can be selected to be 10 to 90% of the sealing plate, and the vertical length can be selected to be 10 to 90% of the sealing plate.

[0035] The blade-type battery according to the present embodiment is provided with lids at both ends of the battery container, and the terminal members provided on the lids function corresponding to the positive electrode and the negative electrode of the electrode assembly housed in the battery container. The terminal members at both ends can be electrically connected to the positive electrode and the negative electrode of the electrode assembly by lead wires. Regarding the lids according to the present embodiment, it is preferable to arrange the terminal member disposed on the lid provided at one end of the battery container to correspond to the positive electrode, and the terminal member disposed on the lid provided at the other end of the battery container to correspond to the negative electrode. For example, the lid 1 having the explosion-proof valve 8 shown in FIG. 1 may be arranged to correspond to the positive electrode, and the lid 10 having the liquid injection hole 11 shown in FIG. 4 may be arranged to correspond to the negative electrode.

[0036] (Joint Structure) In FIG. 2, the joint structure 9 in the region where the terminal member 2 and the sealing plate 3 are joined via the sealing material 4 is indicated by a broken line. FIG. 6 is an enlarged view showing the joint structure 9. As shown in FIG. 6, the terminal member 2 has a flange portion 12 on its outer peripheral surface, and the sealing material 4 may have a structure provided with a first flange locking portion 13 on the side facing the flange portion 12. The sealing plate 3 has a flange portion 14 on the inner wall surface of the mounting hole 5, and the sealing material 4 may have a structure provided with a second flange locking portion 15 on the side facing the flange portion 14. By providing such a locking structure, the terminal member and the sealing plate are more firmly joined via the sealing material, and a sealing structure with excellent sealing performance (airtightness) can be realized.

[0037] The number of flange portions provided on the outer peripheral surface of the terminal member is not limited. One or two or more flange portions may be provided. For example, the terminal member 2 shown in FIG. 6 has two flange portions, namely a first flange portion 12A and a second flange portion 12B. In addition, the height and the protruding length of the flange portion are not limited. The height and the protruding length can be selected in the range of 10 to 90% with respect to the thickness of the terminal member.

[0038] (Shape of Sealing Material) The sealing material is disposed around the terminal member, as it is used to join and attach the terminal member to the mounting hole of the sealing plate. The sealing material is not particularly limited in shape or size, as long as it can reliably seal the terminal member in the mounting hole. For example, in the case of the lid shown in Figures 1 to 6, since the flange portion is provided on the outer peripheral surface of the terminal member 2, the sealing material is arranged in a stepped manner so as to surround the flange portion 12.

[0039] In the blade-type battery according to the present embodiment, the terminal member has a hydroxyl group-containing film on its outer peripheral surface, the sealing plate has a hydroxyl group-containing film on the inner wall surface of the mounting hole, and the sealing material contains a polyarylene sulfide resin as a thermoplastic resin and further contains an acrylate ester.

[0040] The hydroxyl groups of the hydroxyl group-containing film on the outer peripheral surface of the terminal member and the hydroxyl groups of the hydroxyl group-containing film on the inner wall surface in the mounting hole of the sealing plate interact with the carbonyl groups of the acrylate ester contained in the sealing material, so that the terminal member and the sealing plate are firmly adhered to each other, formation of voids (air layers) at the interface between the two is suppressed, and a lid body with excellent sealing performance can be obtained.

[0041] (Hydroxyl Group-Containing Film) The hydroxyl group-containing film according to the present embodiment can be selected according to the type of metal forming the terminal member and the sealing plate. For example, aluminum hydroxide (Al(OH) ３ ), aluminum oxyhydroxide (AlO(OH)), copper hydroxide (Cu(OH) ２ ), iron(II) hydroxide (Fe(OH) ２ ), and the like, and examples thereof include metal hydroxides (metal hydroxides) such as iron(III) oxyhydroxide (FeO(OH)), or metal oxyhydroxides (metal oxyhydroxides). The hydroxyl group-containing film may also be selected according to the metal forming the terminal member and the sealing plate, for example, aluminum oxide (Al ２ O ３ ), copper(I) oxide (Cu ２ O), copper(II) oxide (CuO), iron(II) oxide (FeO), iron(II,III) oxide (Fe ３ O ４ ), iron(III) oxide (Fe ２ O ３It may also contain metal oxides such as ).

[0042] The hydroxyl group-containing film according to this embodiment can be formed by known methods. For example, formation methods such as laser treatment by irradiation with laser light, hydrated oxide treatment with hot water or hot water, zincate treatment, and chemical conversion treatment containing an organic compound component having hydroxyl groups can be used. Laser treatment is advantageous and preferred in that it creates irregularities on the surface and exhibits an anchoring effect. By laser treatment, a hydroxyl group-containing film can be formed in which oxygen elements are localized on the surface layer such that the oxygen content measured by EPMA in the surface layer up to a depth of 3 μm from the outermost surface is 0.1% by mass or more and 50% by mass or less.

[0043] As described above, in a lid provided with a flange portion on the terminal member and / or sealing plate, the hydroxyl group-containing film is formed on the surface of the flange portion, and an interaction occurs between the hydroxyl groups of the hydroxyl group-containing film and the carbonyl groups of the sealing material, resulting in an even stronger sealing structure.

[0044] (Polyarylene sulfide resin) The sealing material for the blade-type battery according to this embodiment preferably contains polyarylene sulfide resin as a thermoplastic resin. Polyarylene sulfide resin is an insulating resin and has resistance to fluorine-containing compounds and hydrogen fluoride contained in the electrolyte in the electrolyte solution, so it can provide a sealing material with excellent adhesion to metal, chemical resistance, heat and cold resistance, good moldability, etc. The content of polyarylene sulfide resin in the sealing material is preferably 50% by mass or more and 100% by mass or less, the lower limit of the content is more preferably 70% by mass or more, and even more preferably 80% by mass or more. The upper limit of the content is more preferably 99.9% by mass or less, and even more preferably 99.8% by mass or less.

[0045] Polyarylene sulfide resins have a structure in which benzene rings (p-phenylene groups) and sulfur atoms (sulfide bonds) are alternately bonded, similar to polyphenylene sulfide. Specifically, examples include one or more homopolymers or copolymers selected from the group consisting of p-phenylene sulfide units, m-phenylene sulfide units, o-phenylene sulfide units, phenylene sulfide sulfone units, phenylene sulfide ketone units, phenylene sulfide ether units, and biphenylene sulfide units. More specifically, examples include poly(p-phenylene sulfide), polyphenylene sulfide sulfone, polyphenylene sulfide ketone, and polyphenylene sulfide ether. Poly(p-phenylene sulfide) is particularly preferred from the viewpoint of excellent heat resistance and strength properties.

[0046] (Acrylic acid ester) The acrylic acid ester contained in the encapsulant is not limited as long as it has a carbonyl group that can interact with the hydroxyl group-containing film. From the viewpoint of facilitating injection molding and obtaining higher adhesion, it is preferable to include one or more selected from the group consisting of methyl acrylate, ethyl acrylate, butyl acrylate, 2-dimethylaminoethyl acrylate, and 2-hydroxyethyl acrylate.

[0047] The content of acrylic acid ester in the sealing material is preferably 0.1% by mass or more and 20% by mass or less, from the viewpoint of ensuring airtightness between the terminal member and the mounting hole of the sealing plate. If the content is less than 0.1% by mass, there is a risk that sufficient airtightness between the terminal member and the mounting hole of the sealing plate cannot be ensured, on the other hand, if it exceeds 20% by mass, the effect of the airtightness will saturate. Within the above content range, sufficient airtightness can be ensured. The lower limit of the acrylic acid ester content is more preferably 0.05% by mass or more, and even more preferably 0.10% by mass or more. The upper limit of the acrylic acid ester content is more preferably 19% by mass or less, and even more preferably 17% by mass or less.

[0048] (Polyolefin) The sealing material according to this embodiment preferably contains one or more polyolefins selected from the group consisting of polyethylene and polypropylene. From the viewpoint of ensuring sufficient resistance to external impacts (impact resistance), the sealing material preferably contains a polyarylene sulfide resin and an acrylic acid ester, and further contains a polyolefin.

[0049] From the viewpoint of obtaining a lid with excellent impact resistance, the sealing material containing polyolefin preferably contains 0.1% by mass or more and 40% by mass of polyolefin. If the polyolefin content is less than 0.1% by mass, the impact resistance effect may not be sufficiently obtained, on the other hand, if it exceeds 40% by mass, the effect will saturate. Within the above content range, a lid with excellent impact resistance can be obtained. Specifically, as shown in the examples described later, the Charpy impact strength (with notch) measured according to ISO 179 for a notched test piece (notch tip radius rN of 0.25 mm ± 0.05 mm) obtained by injection molding was 4 kJ / m ２ The above range can be achieved. The lower limit of the polyolefin content is more preferably 0.2% by mass or more, and even more preferably 0.3% by mass or more. The upper limit of the polyolefin content is more preferably 30% by mass or less, and even more preferably 20% by mass or less.

[0050] In a sealing material containing an acrylic acid ester and a polyolefin, an olefin copolymer of the acrylic acid ester and the polyolefin may be included. Specifically, this is an olefin copolymer obtained by copolymerizing one or more selected from the group consisting of methyl acrylate, ethyl acrylate, butyl acrylate, 2-dimethylaminoethyl acrylate, and 2-hydroxyethyl acrylate with one or more polyolefins selected from the group consisting of polyethylene and polypropylene, and this copolymer is included as an elastomer in the polyarylene sulfide resin.

[0051] (Polydimethylsiloxane) The encapsulant according to this embodiment may contain polydimethylsiloxane (PMDS) as an additive. The inclusion of polydimethylsiloxane can improve the fluidity and release properties of the resin composition, which is the raw material for the encapsulant. Therefore, when the resin composition is injected into a mold to form the encapsulant, the processability can be improved.

[0052] In the encapsulant, it is preferable to contain polydimethylsiloxane (PMDS) in an amount of 0.2% by mass or more and 10% by mass or less. If the polydimethylsiloxane content is less than 0.2% by mass, the effects on fluidity and mold release may not be sufficiently obtained, while if it exceeds 10% by mass, the above effects become saturated. Within the above content range, processability by injection molding can be improved. Specifically, as shown in the examples described later, the resin composition to be injected can be made to have a melt flow rate (MFR) of 20 g / min or more, measured at 315°C and a 5.00 kg load according to the method in accordance with JIS K 7315-2. The lower limit of the polydimethylsiloxane content is more preferably 0.3% by mass or more, and even more preferably 0.5% by mass or more. The upper limit of the polydimethylsiloxane content is more preferably 9.6% by mass or less, and even more preferably 9.0% by mass or less.

[0053] As shown in Figure 7, the blade-type battery 17 according to this embodiment has a battery container 16 that houses electrode bodies having a positive electrode and a negative electrode, and has a sealed structure in which a lid 1 is provided to close the opening of the battery container 16. The terminal member 2 of the lid 1 is attached to the sealing plate 3 via a sealing material 4, and the terminal member 2 and the electrode bodies in the battery container are electrically connected via lead wires.

[0054] (Manufacturing Method) The method for manufacturing the blade-type battery according to this embodiment is not limited. For example, the lids attached to both ends of the battery container can be manufactured by injection molding. Specifically, a manufacturing method can be used that includes the steps of: arranging the sealing plate and the terminal members constituting the lid in a mold of an injection molding apparatus, and arranging them with a gap between the mounting holes of the sealing plate and the terminal members; injecting a resin that forms the sealing material into the mold; and removing the lid, which is sealed by the sealing material with the terminal members joined to the mounting holes of the sealing plate, from the mold.

[0055] The method for manufacturing a blade-type battery according to this embodiment will be described below with reference to Figures 8 to 10. Figures 8 to 10 schematically show an example of a method for manufacturing a lid for a blade-type battery using an injection molding apparatus, in cross-sectional view. The injection molding apparatus 31 illustrated in Figure 8 is a type called a "three-part mold apparatus" that includes a movable mold 32, an intermediate plate 33, and a fixed mold 34. Hereinafter, the part consisting of the movable mold, intermediate plate, and fixed mold will be referred to as the "mold". The injection molding apparatus 31 includes a hopper 35 that contains molten resin 37 for forming a sealing material, and an injection cylinder 36 for injecting the molten resin into the mold.

[0056] First, as shown in Figure 8, the terminal member 22 and the sealing plate 23, which are components of the lid, are placed inside the mold of the injection molding apparatus 31. The sealing plate 23 consists of a single piece as shown in Figure 1. The terminal member 22 is placed inside the mounting hole 25 of the sealing plate 23, with a gap between it and the mounting hole 25. The mold is preheated to an appropriate temperature (for example, around 140 to 160°C) depending on the type of resin used.

[0057] Next, as shown in Figure 9, the movable mold 32, intermediate plate 33, and fixed mold 34 are closed to clamp the mold. Then, a molten resin 37 containing polyarylene sulfide resin and acrylic acid ester, melted to about 300°C, is injected into the mold, filling the space between the terminal member 22 and the mounting hole 25 of the sealing plate 23. After that, the mold is cooled, and as shown in Figure 10, the mold is opened to remove the lid 21, which is the injection molded product. The sprue and runner 38 remain in the fixed mold 34. The lid 21, with the terminal member 22 attached to the mounting hole of the sealing plate 23 via the sealing material 24, is removed from the movable mold 32.

[0058] As described above, the molten resin used to form the encapsulant may contain polyarylene sulfide resin and acrylic acid ester, along with polyolefins such as polyethylene and polypropylene, and may also contain additives such as polydimethylsiloxane.

[0059] As described above, the plate-type battery according to this embodiment has a hydroxyl group-containing coating on the outer surface of the terminal member and the inner wall surface of the mounting hole of the sealing plate, and the sealing material contains an acrylic acid ester. Therefore, the hydroxyl groups of the hydroxyl group-containing coating and the carbonyl groups of the acrylic acid ester of the sealing material interact, so that the terminal member and the sealing plate are firmly joined via the sealing material, and a sealing structure with excellent sealing properties (airtightness) can be realized in the battery container.

[0060] (Another Embodiment) Another embodiment will be described below. Figure 20 is a schematic plan view showing the surface side of the lid. Figure 21 is a cross-sectional view perpendicular to the line Z-Z in Figure 20. The lid according to this embodiment comprises a terminal member 62, a sealing plate 63 having a mounting hole 65 to which the terminal member 62 is attached, a resin sealing material 64 for attaching and sealing the terminal member 62 in the mounting hole 65 of the sealing plate 63, and an injection hole 68.

[0061] As shown in Figure 20, in a plan view, the outer periphery 66 of the terminal member 62 has an elliptical shape, and the sealing plate 63 has a rectangular shape. The major axis of the terminal member 62 is positioned along the long side of the sealing plate 63. The sealing material 64 has a burr 67 formed by part of it extending outward from the outer periphery 66. Figure 20 shows an example in which the sealing material 64 has two burrs 67, with the ends of the elliptical major axes on the outer periphery 66 extending toward the short side of the sealing plate 63. The sealing material may have only one burr, and it may be provided on either the side closer to the short side of the sealing plate or on the opposite side.

[0062] Next, a method for manufacturing a lid according to another embodiment described above will be explained. When manufacturing a lid with two burrs, an injection molding apparatus 71 equipped with a mold portion (hereinafter referred to as "mold") consisting of a movable mold 72, an intermediate plate 73, and a fixed mold 74 can be used, as shown in Figure 22. A terminal member 62 and a sealing plate 23 are arranged on the movable mold 72 side. The terminal member 62 is placed in the mounting hole 25 of the sealing plate 63 with a gap between it and the mounting hole 65. Hereinafter, the above gap will be referred to as the cavity. The injection molding apparatus 71 is equipped with a hopper 75 containing molten resin 77 for forming a sealing material 64, an injection cylinder 76 for injecting the molten resin into the mold, a gate 81 for injecting the molten resin 77, and an air vent 82 for exhausting air at the leading edge in the flow direction of the molten resin injected from the gate and flowing in the cavity 80.

[0063] First, the mold described above is heated to approximately 140-160°C. Next, as shown in Figure 23, the movable mold 72, the intermediate plate 73, and the fixed mold 74 are clamped together, and then, for example, a resin composition containing polyarylene sulfide resin and acrylic acid ester is melted at 300°C or higher and injected.

[0064] At that time, the molten resin 77 is injected in two stages. In the first stage injection, the molten resin 77 injected into the cavity 80 occupies a portion of the height of the air vent 82, and the molten resin 77 flows out into the air vent 82, forming a burr 83, while the air is exhausted to the outside of the mold. At this time, as described above, the air that was present in the cavity 80 is pushed out by the molten resin 77 flowing inside the cavity. As a result, the air taken in as the molten resin 77 flows, along with the gas contained in the molten resin 77, is collected at the front of the flow direction (flow front), so the molten resin at the front of the flow direction (i.e., the molten resin in the flow front portion), which contains a relatively large amount of air, flows out into the air vent 82.

[0065] Next, as the second stage of the two-stage injection, molten resin 77 is further injected into the cavity 80 to form a sealant 64. This fills areas where shrinkage occurred due to the first stage of injection, thereby increasing the density of the molten resin 77 forming the sealant 64 within the cavity 80.

[0066] In the production of the lid described above, in addition to the two-stage injection method in which the resin is injected in two separate stages as described above, the process may also be divided into, for example, a first stage in which the flow rate of the injected resin is controlled, and a second stage in which the pressure of the injected resin is controlled. With such control, the molten resin 77 can be released into the air vent 82 to form a burr 83. In addition, since air is exhausted to the outside of the mold, the molten resin 77 can be further filled, increasing the density of the molten resin 77 that forms the sealing material 64 in the cavity 80.

[0067] After the mold has cooled, the mold is opened as shown in Figure 24. A lid 61 is formed in the fixed mold 74, with the terminal member 62 attached by a sealing material 64 in the mounting hole 65 of the sealing plate 63. A lid is obtained in the sealing material 64 having burrs 67 as shown in Figure 20.

[0068] (Another Embodiment) Another embodiment will be described below. As shown in the plan views of Figures 25 and 26, the lid according to this embodiment comprises a terminal member 92, a sealing plate 93 having a mounting hole (not shown) to which the terminal member 62 is attached, a resin sealing material 94 for attaching and sealing the terminal member 92 in the mounting hole of the sealing plate 93, and a liquid injection hole 98. The outer periphery of the terminal member can have a part of its shape changed. For example, as shown in Figures 25 and 26, if the terminal member 92 is substantially quadrangular in plan view and its long side is aligned with the long side of the sealing plate 93, it can be made into a shape in which the four corners 96 of its outer periphery 95 are cut out. The cut-out portion will be referred to below as the "cut-out portion".

[0069] The terminal member 92 may have one or more notches 97 at the corners 96 of its outer circumference 95. Figure 25 shows an example in which each of the four corners 96 has a notch 97. Figure 26 shows an example in which two corners 96 located on opposite sides have notches 97. The two notches 97 may be provided at corners located on the same side. Notches may be provided at three of the four corners, or at any one of the corners.

[0070] The blade-type battery according to this embodiment has a lid structure that provides airtightness to prevent electrolyte leakage and the intrusion of moisture from the outside. To evaluate the airtightness of the lid structure, test lids as shown in Figures 11 to 18 were fabricated and various evaluation tests were performed. The test lid has a structure in which terminal members are attached to mounting holes in the sealing plate by a sealing material, and its structure is substantially the same as the lid structure shown in Figures 1 and 4.

[0071] Figure 11 is a plan view of the test cover, and Figure 12 schematically shows a cross-section perpendicular to the line A-A in Figure 11. Figure 13 shows a cross-section perpendicular to the line B-B in Figure 11. Figure 14 shows a cross-section of the area where the sealing plate, terminal member, and sealing material are joined in Figure 11. Figure 15 is a diagram illustrating the shape of the test cover. Figures 16 and 17 show the top and bottom surfaces of the sealing plate used in the test cover of Figure 11, respectively. Figures 18 and 19 show the top and bottom surfaces of the terminal member used in the test cover of Figure 11, respectively. The procedure for manufacturing the test cover is as follows.

[0072] (Preparation of sealing plate and terminal member) As shown in Figures 16 and 17, a rectangular sealing plate 43 made of A3003 aluminum alloy plate was prepared, measuring 28 mm in the vertical direction, 105 mm in the horizontal direction, and 2.0 mm in thickness. The mounting hole 45 provided in the sealing plate 43 had a shape consisting of two straight sections 45A and two curved sections 45B and 45C, with the straight section 45A having a shape of 40 mm in the horizontal direction. The curved sections had a radius of curvature of 10 mm for the first curved section 45B on the upper side and a radius of curvature of 10.5 mm for the second curved section 45C on the lower side.

[0073] As shown in Figures 14 and 15, a flange portion 51 of the sealing plate 43 was provided on the inner wall surface of the mounting hole 45. The shape of the flange portion 51 was such that it had a protruding length of 0.5 mm and a height of 1.3 mm. The protruding length and height of the flange portion refer to sizes calculated based on locations identified when the flange portion is viewed in cross-section, as shown in Figures 14 and 15. In this specification, the "height" of the flange portion is used interchangeably with "thickness".

[0074] As shown in Figures 18 and 19, an aluminum electrode made of A1050 material was prepared as the terminal member 42. The terminal member 42 was plate-shaped with a thickness of 3.8 mm and consisted of two straight sections 46 and two curved sections 47, with the straight section 46 having a shape of 40 mm in the lateral direction. The curved section 47, when viewed from the inside, had the shape of a first curved section 47A with a radius of curvature of 7 mm, a second curved section 47B with a radius of curvature of 7.5 mm, and a third curved section 47C with a radius of curvature of 9.0 mm. On the outer circumferential surface of the terminal member, a first flange section 50A and a second flange section 50B were provided, in order from the top surface. The shape of the first flange section 50A was a protruding length of 0.5 mm and a height of 1.7 mm, and the shape of the second flange section 50B was a protruding length of 1.5 mm and a height of 1.6 mm. The protruding length and height of the flange portion refer to the size calculated based on the location identified when viewing the flange portion in cross-section, as shown in Figures 14 and 15.

[0075] (Laser Processing Conditions) The terminal members were subjected to laser processing by irradiating the outer surface, including the flange portion, with a laser. The sealing plate was subjected to laser processing on the inner wall surface, including the flange portion of the mounting hole. The conditions for the laser processing are as follows: • Equipment: KEYENCE 3Axis Fiber laser marker (Model: MDF-5200) • Laser wavelength: 1090 nm • Transmission method: Pulse • Output: 42.5 W • Frequency: 60 kHz • Beam diameter: 60 μm • Irradiation interval: 90 μm • Scanning speed: 340 mm / s • Number of scans (number of irradiations): 1 • Energy density: 1.45 J / mm ２

[0076] (Preparation of encapsulant) As shown in the "Resin composition" column of Table 1, a resin composition for forming the encapsulant was prepared. The resin composition contains the following components (A) to (D): (A) component: polyarylene sulfide resin (B) component: acrylic acid ester (C) component: polyethylene (D) component: polydimethylsiloxane For component (B) above, one or more of the group consisting of (b-1) butyl acrylate, (b-2) methyl acrylate, and (b-3) ethyl acrylate were blended. The content percentages of components (A) to (D) in Table 1 are shown in mass%.

[0077] To evaluate the fluidity of the resin composition, the melt flow rate (MFR) of the resin composition was measured according to the method in accordance with JIS K 7315-2. The resin composition of Test Example No. 1 was used as the test subject, and its MFR was measured under conditions of 315°C and a 5.00 kg load. The measurement result was 50 g / min.

[0078] A test lid was fabricated by injection molding using the above resin composition. The fabrication procedure is based on the lid manufacturing process using the injection molding apparatus shown in Figures 8 to 10. The injection molding conditions are as follows: • Mold temperature: 140°C to 160°C • Molten resin temperature: 290°C to 310°C • Injection speed: 50 to 80 mm / sec • Filling peak pressure: 60 to 120 MPa • Holding pressure: 60 to 80 MPa • Cooling time: 20 to 30 seconds

[0079] (Test Covers) Test covers No. 1 to No. 18 were manufactured according to the procedure described above, as shown in Table 1. The shapes of the test covers are as shown in Figures 11 to 15. As shown in Figures 11 to 13, the test cover 41 has a terminal member 42 attached to the mounting hole 45 of the sealing plate 43 via a sealing material 44. In Figure 12, the joining structure 52 in which the terminal member 42 and the sealing plate 43 are joined via the sealing material 44 is shown by a dashed line. Figure 14 is an enlarged view of the joining structure 52. As shown in Figure 14, the terminal member 42 has a first flange portion 50A and a second flange portion 50B on its outer circumferential surface, and the sealing material 44 has a structure in which a first flange locking portion 53A is located on the side facing the first flange portion 50A and the second flange portion 50B. The sealing plate 43 has a flange portion 51 on the inner wall surface of the mounting hole 45, and the sealing material 44 has a structure in which a second flange locking portion 53B is located on the side facing the flange portion 51.

[0080] The shape and dimensions of the test cover shown in Figure 11 are as follows: The straight portion 46 of the terminal member 42 and the straight portion 48 of the sealing material 44 have a lateral length of 40 mm. The curved portion 47 of the terminal member 42 has a radius of curvature of 7.0 mm. For the curved portion 49 of the sealing material 44, the radius of curvature of the first curved portion 49A is 7.5 mm, the radius of curvature of the second curved portion 49B is 9.5 mm, and the radius of curvature of the third curved portion 49C is 11.5 mm, starting from the inside.

[0081] In Figure 11, when the distance between the outer periphery of the region consisting of the terminal member 42 and the sealing material 44 and the outer periphery of the sealing plate 43 is shown in the lateral direction, the outer periphery of the region is 3.5 mm away from one end of the sealing plate and 38.5 mm away from the other end of the sealing plate. When this distance is shown in the vertical direction, the outer periphery of the region is 2.5 mm away from both ends of the sealing plate.

[0082] Figure 14 shows specific points regarding the shapes of the terminal member 42, sealing plate 43, and sealing material 44. Specifically, when viewing a cross-section of the joint structure 52 as shown in Figure 14, the terminal member 42 shows the end portion 42a of the surface of the terminal member, the tip 42b of the first flange portion 50A, the tip 42c of the second flange portion 50B, the height T1 of the first flange portion 50A, and the height T2 of the second flange portion 50B. For the sealing plate 43, the tip 43a of the flange portion 51, the inner wall surface 43b of the mounting hole 45, and the height T3 of the flange portion 51 are shown. The sealing material 44 is shown as having the following dimensions: the open end (opposite side of the mounting hole) 44a of the first flange locking portion 53A, the open end 44b of the second flange locking portion 53B, the open end (mounting hole side) 44c of the first flange locking portion 53A, the height T4 of the open end of the first flange locking portion 53A, and the height T5 of the open end of the second flange locking portion 53B.

[0083] The joint structure 52 shown in Figure 14 is located at the outer periphery of the terminal member, as shown in Figure 12. Figure 15 is a schematic diagram illustrating the shape and dimensions of the test cover, showing the lengths of the two joint structures 52A and 52B located at the outer periphery of the terminal member 42 when viewed from the side, as shown in Figure 12. For example, the distance (length) between the end 42a of one joint structure 52A and the end 42a of the other joint structure 52A is indicated by the reference numeral 42aL. Similarly, the other reference numerals 42bL, 42cL, 43aL, 43bL, 44aL, 44bL, and 44cL indicate the distances (lengths) between the two joint structures.

[0084] The values ​​for 42aL, etc., shown in Figure 15 are as follows: 42aL: 54mm, 42bL: 55mm, 42cL: 58mm, 43aL: 60mm, 43bL: 61mm, 44aL: 59mm, 44bL: 63mm, 44cL: 56.4mm

[0085] Regarding the height of the flange portion, the values ​​for T1, etc., shown in Figure 14 are as follows: T1: 1.7 mm, T2: 1.6 mm, T3: 1.3 mm, T4: 1.5 mm, T5: 1.2 mm

[0086] The values ​​shown in Figure 14 regarding the protruding lengths of the flange portions are as follows: The protruding length of the first flange portion 50A of the terminal member is 0.5 mm, which corresponds to (42 bL - 42 aL) / 2. The height of the second flange portion 50B of the terminal member is 1.5 mm, which corresponds to (42 cL - 42 bL) / 2. The protruding length of the flange portion 51 of the sealing plate is 0.5 mm, which corresponds to (43 bL - 43 aL) / 2.

[0087] Using each of the obtained test lids, the following parameters were measured to evaluate the characteristics related to "bonding strength": "oxygen content in the hydroxyl group-containing coating (hereinafter also referred to as "coating oxygen content")", "pressure strength", "sealing properties", and "Charpy impact strength".

[0088] (Oxygen content in the film) Cross-sectional mapping was performed on the flange portion of the terminal member before the sealing material was applied, using an Electron Probe Micro Analyzer (EPMA) (Shimadzu Corporation: EPMA-1610). The measurement conditions were a mapping analysis performed with an irradiation diameter of 40 μm / step and 512 steps each in the longitudinal and transverse directions. The measurement area was 20.48 mm × 20.48 mm, the sampling time per step was 20 ms, the acceleration voltage was 15 kV, and the oxygen depth resolution was 3 μm or less.

[0089] Next, the detected oxygen intensity was calculated as a weight percentage (wt%) based on a calibration curve prepared in advance. The calibration curve was Al ２ O ３ The oxygen intensity was calculated from two points: the oxygen intensity of a standard sample (oxygen content: 48 wt%) and the oxygen intensity of high-purity Al foil. The results are shown in Table 1.

[0090] (Pressure Strength) To evaluate the adhesion of the sealing material to the terminal members in the test lid, the pressure strength was measured using a Toyo Seiki Seisakusho universal testing machine (STROGRAPH T200) according to the following procedure. The test lid was set on the sample stage of the universal testing machine, and then the tip of the pressing jig was pressed down on the terminal members from directly above at a constant speed (10 mm / min). The load at which the sealing material broke so that the terminal members came off the mounting holes of the sealing plate was calculated as the "pressure strength". A pressure strength of 1000 N or more was judged as a pass, and a pressure strength of less than 1000 N was judged as a fail.

[0091] (Sealing Performance) To evaluate the sealing performance (airtightness) of the terminal members on the test cover, a helium leak test was performed using a helium leak detector (HELIOT 901W1, manufactured by ULVAC, Inc.) according to the following procedure. First, one of the terminal members on the test cover was set on the lower fixture made of SUS304 attached to the helium leak detector via an O-ring. Then, when the helium leak value was 1 × 10⁻⁶ －１２ Pa・m ３ Vacuuming was performed using a roughing pump and a turbomolecular pump until the level reached / s.

[0092] Next, a SUS304 upper fixture was placed on the test cover via an O-ring. Then, helium (He) gas was injected into the upper fixture, a resin cover was placed over the opening of the upper fixture, and the amount of He gas leaking from the terminal member sealed with a sealing material was detected. The He leak value was 1 × 10⁻⁶. －７ Pa・m ３ If the result is less than / s, it is judged as a pass, and 1 × 10 －７ Pa・m ３ If the value was / s or higher, it was judged as a failure.

[0093] (Joint Strength) Based on the judgment results for the above pressing strength and sealing properties, the joint strength between the terminal member and the sealing plate was evaluated. If both items were judged to be satisfactory, the joint strength was evaluated as excellent (A). If either item was judged to be unsatisfactory, the joint strength was evaluated as good (B). If both items were unsatisfactory, the joint strength was evaluated as average (C). The results are shown in Table 1. In Table 1, "excellent" is indicated by the symbol A, "good" by the symbol B, and "average" by the symbol C.

[0094] (Charpy Impact Strength) To evaluate the mechanical strength of the sealing material, the Charpy impact strength was measured using a notched test specimen in accordance with ISO 179 / 1eA. Notched test specimens (notch tip radius rN of 0.25 mm ± 0.05 mm) were prepared as resin molded products manufactured by injection molding of the resin composition. The Charpy impact strength (kJ / m) was measured using these test specimens. ２ The following was measured. The results are shown in Table 1.

[0095] (Overall Evaluation) An overall evaluation was conducted based on the evaluation results for each item: joint strength and Charpy impact strength. If the joint strength is excellent (A) or good (B), the Charpy impact strength (kJ / m ２ Test examples in which the Charpy impact strength (kJ / m) is 4 or higher will be evaluated as excellent (A) in the overall evaluation, and the Charpy impact strength (kJ / m) will be evaluated as excellent (A). ２ In cases where the score was less than 4, the overall evaluation was rated as good (B).

[0096] On the other hand, when the joint strength is normal (C), the Charpy impact strength (kJ / m ２ In all cases where the score was 4 or higher or less than 4, the overall evaluation was given as average (C). Table 1 shows that "Excellent" is indicated by the symbol A, "Good" by the symbol B, and "Average" by the symbol C.

[0097]

[0098] As can be seen from the results shown in Table 1, by including an acrylic acid ester along with polyarylene sulfide resin as the resin forming the encapsulant, a lid structure with excellent sealing and adhesion can be achieved. Therefore, it was confirmed that a sealed blade-type battery with a simple structure can be provided that reliably prevents electrolyte leakage and the intrusion of moisture from the outside.

[0099] 1 Cover 2 Terminal member 3 Sealing plate 4 Sealing material 5 Mounting hole 6 Straight section 6A First straight section 6B Second straight section 7 Curved section 7A First curved section 7B Second curved section 8 Explosion-proof valve 9 Joint structure 10 Cover 11 Injection hole 12 Flange section (terminal member) 12A First flange section (terminal member) 12B Second flange section (terminal member) 13 First flange locking section (side facing terminal member) 14 Flange section (sealing plate) 15 Second flange locking section (side facing sealing plate) 16 Battery container 17 Blade-type battery 21 Cover 22 Terminal member 23 Sealing plate 24 Sealing material 25 Mounting hole 31 Injection molding machine 32 Movable mold 33 Intermediate plate 34 Fixed mold 35 Hopper 36 Injection cylinder 37 Molten resin 38 Sprue and runner 41 Test cover 42 Terminal member 42a End of surface of terminal member 42b Tip of first flange 42c Tip of second flange 42aL Length at 42a 42bL Length at 42b 42cL Length at 42c 43 Sealing plate 43a Tip of flange 43b Inner wall surface of mounting hole 43aL Length at 43a 43bL Length at 43b 44 Sealing material 44a Open end of first flange locking part (opposite side of mounting hole) 44b Open end of second flange locking part 44c Open end of first flange locking part (mounting hole side) 44aL Length at 44a 44bL Length at 44b 44cL Length at 44c 45 Mounting hole 45A 45B Straight portion of mounting hole 45C First curved portion of mounting hole 46 Second curved portion of mounting hole 47 Straight portion of terminal member 47 Curved portion of terminal member 47A First curved portion of terminal member 47B Second curved portion of terminal member 47C Third curved portion of terminal member 48 Straight portion of sealing material 49 Curved portion of sealing material 49A First curved portion of sealing material 49B Second curved portion of sealing material 49C Third curved portion of sealing material 50A First flange portion of terminal member 50B Second flange portion of terminal member 51 Flange portion of sealing plate 52, 52A, 52B Joining structure53A First flange locking portion of the sealing material (side facing the terminal member) 53B Second flange locking portion of the sealing material (side facing the sealing plate) T1 Height of the first flange portion T2 Height of the second flange portion T3 Height of the flange portion T4 Height of the open end of the first flange locking portion T5 Height of the open end of the second flange locking portion 61 Cover 62 Terminal member 63 Sealing plate 64 Sealing material 65 Mounting hole 66 Outer circumference 67 Burr 68 Injection hole 71 Injection molding machine 72 Movable mold 73 Intermediate plate 74 Fixed mold 75 Hopper 76 Injection cylinder 77 Molten resin 80 Cavity 81 Gate 82 Air vent 83 Burr 91 Cover 92 Terminal member 93 Sealing plate 94 Sealing material 95 Outer circumference 96 Corner 97 Notch 98 Injection hole

Claims

1. A sealed blade-type battery comprising a battery container having openings at both ends, an electrode body having a positive electrode and a negative electrode housed in the battery container, and a lid provided to close the openings, wherein the lid comprises terminal members corresponding to the positive electrode and the negative electrode, a sealing plate having mounting holes for attaching the terminal members, and a sealing material for attaching and sealing the terminal members in the mounting holes of the sealing plate, the sealing material containing polyarylene sulfide resin as a thermoplastic resin and containing acrylic acid ester, the terminal members having a hydroxyl group-containing film on their outer circumferential surface, the sealing plate having a hydroxyl group-containing film on the inner wall surface of the mounting holes, and the terminal members being sealed in the mounting holes of the sealing plate via the sealing material.

2. The blade-type battery according to claim 1, wherein the sealing material contains 0.1% by mass or more and 20% by mass or less of acrylic acid ester.

3. The blade-type battery according to claim 1, wherein the acrylic acid ester is one or more selected from the group consisting of methyl acrylate, ethyl acrylate, butyl acrylate, 2-dimethylaminoethyl acrylate, and 2-hydroxyethyl acrylate.

4. The blade-type battery according to claim 1, wherein the hydroxyl group-containing film has an oxygen content of 0.1% by mass or more and 50% by mass or less in the surface layer up to a depth of 3 μm from the outermost surface, as measured by EPMA.

5. The blade-type battery according to claim 1, wherein the sealing material contains one or more polyolefins selected from the group consisting of polyethylene and polypropylene.

6. The blade-type battery according to claim 5, wherein the sealing material contains 0.1% by mass or more and 40% by mass or less of the polyolefin.

7. The blade-type battery according to claim 1, wherein the sealing material contains polydimethylsiloxane as an additive.

8. The blade-type battery according to claim 1, wherein the terminal member of the lid provided at one end of the battery container corresponds to the positive electrode, and the terminal member of the lid provided at the other end of the battery container corresponds to the negative electrode.

9. A method for manufacturing a blade-type battery according to any one of claims 1 to 8, comprising: arranging the sealing plate and the terminal member constituting the lid in a mold of an injection molding apparatus, and arranging them with a gap between the mounting hole of the sealing plate and the terminal member; injecting a resin for forming the sealing material into the mold; and removing the lid, which is sealed by the sealing material with the terminal member joined to the mounting hole of the sealing plate, from the mold.

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