Lead for non-aqueous electrolyte battery

Abstract

To provide a lead for a non-aqueous electrolyte battery which can discharge gas generated in a battery to the outside of a container, when being applied to the battery.SOLUTION: A lead for a non-aqueous electrolyte battery has a conductor 14, and a first insulation resin film 15A and a second insulation resin film 15B which are arranged on an upper face and a lower face of the conductor, wherein the first insulation resin film and the second insulation resin film are arranged so as not to cover both ends in a Y axis of the conductor, to cover a part other than both of the ends of the conductor while crossing the conductor in an X axis, and be overlapped with each other when being viewed in a vertical direction of an upper face, at least one of the first insulation resin film and the second insulation resin film has a first film layer 151 and a second film layer 152 in order from the side closer to the conductor, and the second film layer is arranged so that a part of the surface of the first film layer is exposed, and a kind of the resin thereof is different from that of the first film layer.SELECTED DRAWING: Figure 3A

Description

[Technical field]

[0001] The present disclosure relates to leads for non-aqueous electrolyte batteries. [Background technology]

[0002] Patent Document 1 describes a film exterior body, an electrode assembly housed inside the film exterior body and having electrodes; a plate-shaped terminal having one end electrically connected to the electrode and the other end extending outside the film exterior body; a seal portion provided on at least an edge portion of the film exterior body on the side from which the terminal extends; a sealant film that is integrated with a surface of the terminal facing the film exterior body and is welded to the film exterior body at the seal portion, The sealant film has a cutout portion formed so that the width of the seal portion in the direction in which the terminal extends is narrower than other portions. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2022-100451 A Summary of the Invention [Problem to be solved by the invention]

[0004] In a nonaqueous electrolyte battery such as a lithium ion secondary battery, when the battery is repeatedly charged and discharged, gas may be generated inside the container of the nonaqueous electrolyte battery due to a reaction of the electrolyte, etc. From the viewpoint of preventing damage to the nonaqueous electrolyte battery, when gas is generated inside the nonaqueous electrolyte battery, it is required to configure the battery so that the gas can be discharged outside the system.

[0005] In view of the above, an object of the present disclosure is to provide a lead for a nonaqueous electrolyte battery that, when applied to a battery, enables gas generated within the battery to be discharged to the outside of the container. [Means for solving the problem]

[0006] The lead for a nonaqueous electrolyte battery according to the present disclosure includes a plate-shaped conductor having rectangular upper and lower surfaces, a first insulating resin film disposed on the top surface of the conductor; a second insulating resin film disposed on the lower surface of the conductor; When the conductor is viewed in the vertical direction of the upper surface, an axis along two selected opposing sides is defined as an X-axis, and an axis perpendicular to the X-axis is defined as a Y-axis. the first insulating resin film and the second insulating resin film are arranged so as not to cover both end portions of the conductor along the Y-axis, but to cover the conductor in a portion other than the both end portions along the X-axis, and to overlap each other when viewed along the vertical direction of the upper surface; At least one of the first insulating resin film and the second insulating resin film has a first film layer and a second film layer in this order from a position closest to the conductor, The second film layer is disposed so that a portion of the surface of the first film layer is exposed, and is made of a different type of resin from that of the first film layer. Effect of the Invention

[0007] According to the present disclosure, it is possible to provide a lead for a nonaqueous electrolyte battery that, when applied to a battery, enables gas generated within the battery to be discharged to the outside of the container. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is an explanatory diagram of a battery to which a lead for a nonaqueous electrolyte battery according to one embodiment of the present disclosure is applied. [Diagram 2] FIG. 2 is a top view of a lead for a nonaqueous electrolyte battery according to one embodiment of the present disclosure. [Figure 3A] FIG. 3A is a cross-sectional view taken along line AA' in FIG. [Figure 3B] FIG. 3B is a cross-sectional view taken along the line AA′ in FIG. 1 showing another example of the configuration. [Figure 4] FIG. 4 is a top view of a lead for a nonaqueous electrolyte battery according to another embodiment of the present disclosure. [Diagram 5] FIG. 5 is a top view of a lead for a nonaqueous electrolyte battery according to another embodiment of the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] The embodiments for carrying out the invention are described below.

[0010] [Description of the embodiments of the present disclosure] First, the embodiments of the present disclosure will be described. In the following description, the same or corresponding elements are denoted by the same reference numerals, and the same description thereof will not be repeated.

[0011] (1) A lead for a nonaqueous electrolyte battery according to one embodiment of the present disclosure includes a plate-shaped conductor having rectangular upper and lower surfaces, a first insulating resin film disposed on the top surface of the conductor; a second insulating resin film disposed on the lower surface of the conductor; When the conductor is viewed in the vertical direction of the upper surface, an axis along two selected opposing sides is defined as an X-axis, and an axis perpendicular to the X-axis is defined as a Y-axis. the first insulating resin film and the second insulating resin film are arranged so as not to cover both end portions of the conductor along the Y-axis, but to cover the conductor in a portion other than the both end portions along the X-axis, and to overlap each other when viewed along the vertical direction of the upper surface; At least one of the first insulating resin film and the second insulating resin film has a first film layer and a second film layer in this order from a position closest to the conductor, The second film layer is disposed so that a portion of the surface of the first film layer is exposed, and is made of a different type of resin from that of the first film layer.

[0012] When the lead for a nonaqueous electrolyte battery according to one embodiment of the present disclosure (hereinafter also referred to as "lead") is applied to a nonaqueous electrolyte battery (hereinafter also referred to as "battery"), the plate-shaped conductor and the exterior body, which corresponds to the battery container, can be closely attached and joined via the insulating resin film. Therefore, by having the insulating resin film in the lead according to one embodiment of the present disclosure, a seal portion can be formed along the periphery of the exterior body, including the portion where the lead is arranged, and the electrode stack and the electrolyte can be sealed.

[0013] The second film layer makes it possible to adjust the adhesion between the insulating resin film and the exterior body of the battery.

[0014] Specifically, the adhesion between the insulating resin film and the battery's exterior body can be weakened at the location where the second film layer and the battery's exterior body contact each other, compared to the location where the first film layer and the battery's exterior body contact each other.

[0015] Therefore, by having the insulating resin film have the second film layer, when the pressure inside the battery exterior increases, the insulating resin film can be cleaved starting from the contact point between the second insulating resin film and the battery exterior, forming a gas exhaust path that allows the gas inside the battery exterior to be exhausted to the outside, thereby preventing the battery from being damaged, etc., even if gas is generated inside the battery exterior.

[0016] (2) In the above (1), the second film layer is shorter than the first film layer in both the length along the X-axis and the length along the Y-axis, The first film layer and the second film layer may be disposed such that the positions on the Y axis of one side of each of the first and second film layers coincide with each other.

[0017] By making the length of the second film layer along the X-axis of the conductor and the length of the second film layer along the Y-axis of the conductor shorter than those of the first film layer, the exposed area of ​​the first film layer can be increased. Therefore, when applied to a battery, the working pressure, which is the pressure at which gas inside the exterior body is exhausted to the outside, can be adjusted while particularly improving the adhesion between the battery exterior body and the insulating resin film.

[0018] By arranging the first film layer and the second film layer so that the positions on the Y axis of one side coincide with each other, when the lead is applied to the battery, one side of the second film layer can be arranged inside the exterior body of the battery. Therefore, when the pressure inside the exterior body increases, one side of the second film layer can directly contact the gas generated inside the exterior body, making it easier to cleave. Therefore, when the pressure inside the exterior body increases, the reactivity to the pressure is increased, and when the pressure inside the exterior body reaches a desired pressure, the gas inside the exterior body can be discharged to the outside.

[0019] (3) In the above (1), a length obtained by subtracting a length of the second film layer along the Y axis from a length of the first film layer along the Y axis is 0 mm or more and 1 mm or less, a length of the second film layer along the X-axis is less than a length of the first film layer along the X-axis; The first film layer and the second film layer may be disposed such that the positions on the Y axis of one side of each of the first and second film layers coincide with each other.

[0020] When the length of the second film layer along the Y axis is set to be the same as the length of the first film layer along the Y axis, the second film layer can be arranged to connect the inside and outside of the battery exterior body, thereby lowering the operating pressure at which gas inside the exterior body is exhausted to the outside when the pressure inside the exterior body increases.

[0021] (4) In the above (1), the lengths of the sides of the second film layer located at both ends of the Y axis are different, The first film layer and the second film layer may be disposed such that the positions on the Y axis of one side of each of the first and second film layers coincide with each other.

[0022] By configuring the second film layer so that the lengths of both sides along the Y axis of the conductor are different, it is possible to adjust the responsiveness to pressure within the exterior body and the ease with which gas within the exterior body can be released to the outside.

[0023] (5) In any one of the above (1) to (4), the first film layer may contain, as a resin, one or more types selected from a polyolefin resin, a polyester resin, a polystyrene resin, and a polyvinyl chloride resin.

[0024] When the first film layer contains one or more resins selected from polyolefin resins, polyester resins, polystyrene resins, and polyvinyl chloride resins, the adhesion between the insulating resin film and the exterior body can be improved.

[0025] (6) In any one of the above (1) to (5), the second film layer may contain, as a resin, one or more types selected from a polyimide resin, a polyester resin, and a fluorine-based resin.

[0026] When the second film layer contains one or more resins selected from polyimide resins, polyester resins, and fluorine-based resins, the adhesive strength between the insulating resin film and the exterior body can be easily adjusted.

[0027] [Details of the embodiment of the present disclosure] Specific examples of a lead for a nonaqueous electrolyte battery according to an embodiment of the present disclosure (hereinafter, referred to as the present embodiment) will be described below with reference to the drawings. Note that the present invention is not limited to these examples, but is defined by the claims, and is intended to include all modifications within the meaning and scope equivalent to the claims.

[0028] In this specification, the names of components may be described with suffixes such as "first" and "second", such as "first insulating resin film", "second insulating resin film", "first film layer", and "second film layer". The suffixes such as "first" and "second" are merely used to distinguish between components and to prevent confusion during description, and do not represent arrangement, priority, or the like. For this reason, when there is no particular risk of confusion or when referring to components collectively, they may simply be referred to as "insulating resin film" and "film layer". [Leads for non-aqueous electrolyte batteries] FIG. 1 shows an explanatory diagram of a configuration example when the lead for a nonaqueous electrolyte battery of this embodiment is applied to a nonaqueous electrolyte battery. FIG. 2 shows an explanatory diagram of the lead for a nonaqueous electrolyte battery of this embodiment when viewed along the vertical direction of the upper surface of the conductor. FIG. 3A shows a cross-sectional view taken along the line AA' in FIG. 1. FIG. 3B shows another configuration example corresponding to the cross-sectional view taken along the line AA' in FIG. 1. FIG. 4 and FIG. 5 show explanatory diagrams of another configuration example of the lead for a nonaqueous electrolyte battery of this embodiment. Since FIG. 3B, FIG. 4, and FIG. 5 are modified examples of the lead of this embodiment, they will be described mainly using FIG. 1, FIG. 2, and FIG. 3A, and FIG. 3B, FIG. 4, and FIG. 5 will be used as necessary.

[0029] The Z axis in Figs. 1, 2, 3A, 3B, 4 and 5 is an axis along the thickness of the conductor and insulating resin film of the lead of this embodiment.

[0030] The lead 13 of this embodiment can be applied to a non-aqueous electrolyte battery, so after describing a battery to which the lead 13 of this embodiment can be applied, the lead 13 of this embodiment will be described in detail. (1) Regarding batteries A configuration example of a battery to which the lead 13 of this embodiment is applied will be described with reference to Fig. 1. As shown in Fig. 1, a battery 10 can have an exterior body 11, an electrode laminate 12 in which a positive electrode, a separator, and a negative electrode are laminated and impregnated with an electrolyte solution, and a lead 13 according to one embodiment of the present disclosure connected to the electrode laminate 12. (Exterior body) The exterior body 11 is a container that contains and seals the electrode laminate 12 and the electrolyte. At least one resin layer can be disposed on the surface of the exterior body 11 that faces the electrode laminate 12 so that thermal welding can be performed.

[0031] Exterior body 11 is a so-called laminate film, and can have a structure in which first resin layer 111, metal layer 112, and second resin layer 113 are laminated together, for example, as shown in FIG. 3A.

[0032] There is no particular limitation on the type of resin used for the first resin layer 111, and a thermoplastic resin can be suitably used. The same thermoplastic resin as that for the first film layer 151 described later can be suitably used for the first resin layer 111, and therefore a description thereof will be omitted.

[0033] The metal layer 112 is a layer for increasing airtightness, and may be a layer containing a metal material such as aluminum, iron, or stainless steel.

[0034] The second resin layer 113 is a layer for enhancing durability and impact resistance, and like the first resin layer 111, for example, a thermoplastic resin can be suitably used.

[0035] As indicated by the dashed line in FIG. 1, a seal portion 110 is formed on the periphery of the exterior body 11, and the seal portion 110 seals the electrode stack 12 and the electrolyte. (2) About Lead The lead 13 in this embodiment is also called a tab lead or the like, and has a conductor 14 and an insulating resin film 15 .

[0036] Each member of the lead 13 will now be described. (2-1) Conductor The conductor 14 is a member for connecting the electrode laminate 12 disposed in the exterior body 11 to devices disposed outside the exterior body 11. The conductor 14 may have a plate shape, and an upper surface 141 and a lower surface 142 (see FIG. 3A) have a rectangular shape. As shown in FIG. 2, the upper surface 141 of the conductor 14 may have a rectangular or square shape having two opposing sides, sides 14A and 14B, and sides 14C and 14D that intersect with sides 14A and 14B. However, the rectangular shape, oblong shape, and square shape do not mean strict geometric shapes, and the conductor 14 may have a recess or a protrusion required for connection to, for example, the electrode laminate 12 or external devices.

[0037] In the following description, when conductor 14 is viewed from above along the vertical direction of upper surface 141, an axis along two selected opposing sides, sides 14A and 14B, is defined as an X-axis, and an axis perpendicular to the X-axis is defined as a Y-axis.

[0038] There are no particular limitations on the material of the conductor 14, and it is possible to use, for example, various materials used as conductors for leads of nonaqueous electrolyte batteries. Examples of the material of the conductor 14 include metal materials such as aluminum, titanium, nickel, copper, aluminum alloys, titanium alloys, nickel alloys, and copper alloys, and materials obtained by plating these metal materials with nickel, gold, or the like. (2-2) Insulating resin film The insulating resin film 15 includes a first insulating resin film 15A arranged on an upper surface 141 of the conductor 14 and a second insulating resin film 15B (see FIG. 3A) arranged on a lower surface 142 of the conductor 14. As shown in FIGS. 2 and 3A, on the upper surface 141 and the lower surface 142, the first insulating resin film 15A and the second insulating resin film 15B are arranged so as to expose both ends of the conductor 14 along the Y axis, i.e., both ends including sides 14A and 14B, without covering them. Also, on the upper surface 141 and the lower surface 142, the first insulating resin film 15A and the second insulating resin film 15B are arranged so as to cover the conductor 14 across the X axis in an intermediate portion, which is a portion of the conductor 14 other than both ends along the Y axis.

[0039] The first insulating resin film 15A and the second insulating resin film 15B are arranged such that, when viewed along the vertical direction of the upper surface 141, the first insulating resin film 15A arranged on the upper surface 141 and the second insulating resin film 15B arranged on the lower surface 142 overlap each other.

[0040] The upper surface 141 and the lower surface 142 of the conductor 14 refer to the surfaces that face the exterior body 11 of the battery 10 when the battery 10 is manufactured.

[0041] The two ends of the conductor 14 along the Y-axis refer to a first end region 21 including the side 14A and a second end region 22 including the side 14B, as shown in Fig. 2. The intermediate portion is a portion located between the first end region 21 and the second end region 22.

[0042] The first end region 21 is a portion that is exposed to the outside of the exterior body 11 when the lead 13 is applied to a battery, for example, and the size thereof can be selected so that it can be connected to external devices. The second end region 22 is a portion that is located inside the exterior body 11, for example, and is connected to the electrode laminate 12 when the lead 13 is applied to a battery, and the size thereof can be selected so that it can be connected to the electrode laminate 12. The first end region 21 and the second end region 22 may be the same or different in size, such as area.

[0043] When the lead 13 of this embodiment is applied to a battery, the plate-shaped conductor 14 and the exterior body 11 of the battery 10 can be closely attached and joined via the insulating resin film 15. Therefore, since the lead 13 of this embodiment has the insulating resin film 15, a seal portion 110 (see FIG. 1 ) can be formed along the periphery of the exterior body 11, including the portion where the lead 13 is arranged, and the electrode stack 12 and the electrolyte can be sealed.

[0044] At least one of the insulating resin films 15, the first insulating resin film 15A and the second insulating resin film 15B, has a first film layer 151 and a second film layer 152 in this order from the position closest to the conductor 14 (see FIGS. 2 and 3A). That is, at least one of the first insulating resin film 15A and the second insulating resin film 15B has a structure in which the first film layer 151 and the second film layer 152 are laminated in this order on the conductor 14.

[0045] 3A, both the first insulating resin film 15A and the second insulating resin film 15B have the first film layer 151 and the second film layer 152, but are not limited to this. For example, only the first insulating resin film 15A may have the first film layer 151 and the second film layer 152, and the second insulating resin film 15B may have only the first film layer 151. (First film layer) The first film layer 151 is a layer for enabling thermal welding between the first film layer 151 and the exterior body 11 when applied to a battery. For this reason, the first film layer 151 preferably contains a thermoplastic resin as a resin. As the thermoplastic resin, for example, one or more types selected from polyolefin resin, polyester resin, polystyrene resin, polyvinyl chloride resin, etc. can be used. As the polyolefin resin, there can be mentioned acid-modified polyolefin resins such as polyethylene, polypropylene, acid-modified polyethylene, acid-modified polypropylene, etc. As the polyester resin, there can be mentioned polyethylene terephthalate resin, etc. As the acid-modified polyolefin, there can be mentioned maleic anhydride-modified polyolefin.

[0046] When first film layer 151 contains one or more resins selected from polyolefin resin, polyester resin, polystyrene resin, polyvinyl chloride resin, and the like, the adhesion between insulating resin film 15 and the exterior body can be improved.

[0047] The first film layer 151 may be composed of two or more layers as shown in Figures 3A and 3B. The first film layer 151 may have a base layer 151a and a surface layer 151b as shown in Figure 3A. The first film layer 151 may also have a base layer 151a, an intermediate layer 151c, and a surface layer 151b as shown in Figure 3B.

[0048] When the first film layer 151 has multiple layers, each layer can be a layer intended to adjust the adhesion with the conductor 14 or the exterior body 11, or to adjust the strength of the layer derived from the first film layer 151 after bonding with the exterior body 11. Therefore, the material of each layer can be selected according to the intended function. When the first film layer 151 has multiple layers, for example, the thermoplastic resin already described can be suitably used for each layer. The material of the first film layer 151, the number of layers constituting the first film layer 151, etc. may be different between the first insulating resin film 15A and the second insulating resin film 15B.

[0049] The first film layer 151 can have, for example, a rectangular shape when viewed in a direction perpendicular to the top surface 141 of the conductor 14. However, the rectangular shape here does not have a strict geometrical meaning, and for example, the corners of the vertices may be processed to form curves, etc.

[0050] The first film layer 151 is disposed on the upper surface 141 and the lower surface 142 of the conductor 14 so that both end portions of the conductor 14 along the Y axis are exposed and the first film layer 151 covers the entire area along the sides 14A and 14B of the upper surface 141 in an intermediate portion other than both end portions of the conductor 14. That is, the first film layer 151 is disposed so as to expose the first end region 21 and the second end region 22 of the conductor 14. For this reason, the length L151 of the first film layer 151 along the Y axis is shorter than the length L14 of the conductor 14 along the Y axis.

[0051] Furthermore, the length W151 of the first film layer 151 along the X-axis is longer than the length W14 of the conductor 14 along the X-axis. Therefore, the first film layer 151 can be disposed so as to protrude on both sides of the conductor 14 along the X-axis. The first film layer 151 disposed on the upper surface 141 of the conductor 14 and the first film layer 151 disposed on the lower surface 142 of the conductor 14 can be bonded to each other at the portions protruding from the conductor 14. By disposing the first film layer 151 along the X-axis so as to protrude on both sides of the conductor 14 and bonding the first film layers 151 disposed on the upper surface 141 and the lower surface 142 of the conductor 14 to each other, the adhesion between the conductor 14 and the first film layer 151 is increased.

[0052] The shapes of the first film layers 151 disposed on the upper surface 141 and the lower surface 142 of the conductor 14 may be the same or different. However, from the viewpoint of bonding the first film layers 151 to each other at the portions protruding from the conductor 14 as described above, it is preferable that the first film layers 151 disposed on the upper surface 141 and the lower surface 142 of the conductor 14 have the same shape.

[0053] The first film layer 151 may be welded to the conductor 14 or may be attached with an adhesive or the like. (Second film layer) Second film layer 152 is disposed so that a portion of the surface of first film layer 151 is exposed, and may use a different type of resin from that of first film layer 151. When first film layer 151 has a plurality of layers, second film layer 152 may use a different type of resin from that of surface layer 151b, which is the layer of first film layer 151 that is closest to second film layer 152. First film layer 151 and second film layer 152 may be bonded together via an adhesive.

[0054] The second film layer 152 makes it possible to adjust the adhesion between the insulating resin film 15 and the exterior body 11 of the battery 10 .

[0055] Specifically, at the location where the second film layer 152 and the outer casing 11 of the battery 10 contact each other, the adhesion between the insulating resin film 15 and the outer casing 11 of the battery 10 can be weakened compared to the location where the first film layer 151 and the outer casing 11 of the battery 10 contact each other.

[0056] Therefore, by having the second film layer 152 in the insulating resin film 15, when pressure increases inside the exterior body 11 of the battery 10, the insulating resin film 15 can be ruptured starting from the location where the second film layer 152 and the exterior body 11 of the battery 10 contact each other. Then, as shown by the block arrow 31 in Figures 1 and 3A, a gas exhaust path is formed and gas within the exterior body 11 of the battery 10 can be exhausted to the outside, so that even if gas is generated within the exterior body 11 of the battery 10, damage to the battery 10 can be prevented.

[0057] By selecting the material, shape, and area of ​​second film layer 152, the adhesive strength between exterior body 11 and insulating resin film 15 can be adjusted.

[0058] For this reason, second film layer 152 can be configured to be made of a different type of resin than first film layer 151. By using a different type of resin for second film layer 152 than that for first film layer 151, the adhesion between insulating resin film 15 and exterior body 11 of battery 10 can be adjusted.

[0059] Second film layer 152 is preferably made of a resin that is less likely to melt than first film layer 151 when exterior body 11 is heat-sealed. For this reason, the resin used for second film layer 152 is preferably a resin that has a higher melting point than first film layer 151. Second film layer 152 can contain, for example, one or more types of resin selected from polyimide resin, polyester resin, and fluorine-based resin.

[0060] An example of the polyester resin is polyethylene terephthalate resin.

[0061] As the fluorine-based resin, for example, one or more types selected from polytetrafluoroethylene (PTFE), tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer (PFA), polyvinylidene fluoride (PVDF), ethylene-tetrafluoroethylene copolymer (ETFE), tetrafluoroethylene-hexafluoropropylene copolymer (FEP), etc. can be used.

[0062] When second film layer 152 contains one or more types of resin selected from polyimide resin, polyester resin, and fluorine-based resin, the adhesive strength between insulating resin film 15 and the exterior body can be easily adjusted.

[0063] Also, second film layer 152 can be configured to have a smaller area than first film layer 151. For this reason, second film layer 152 can be arranged so that a part of the surface of first film layer 151 is exposed, that is, so that exposed portion 1511 where first film layer 151 is exposed is generated. By arranging second film layer 152 so that a part of the surface of first film layer 151 is exposed, when lead 13 is applied to a battery, it is possible to adjust the adhesion between insulating resin film 15 and exterior body 11 of battery 10.

[0064] When the first insulating resin film 15A and the second insulating resin film 15B both have the second film layer 152, the material, shape, and area of ​​the second film layer 152 may be different or the same between the first insulating resin film 15A and the second insulating resin film 15B.

[0065] An example of the configuration of the second film layer 152 will be described below. (First configuration example) For example, as shown in FIG. 2, the second film layer 152 may be shorter than the first film layer 151 in both the length along the X-axis and the length along the Y-axis.

[0066] That is, the length L152 of the second film layer 152 along the Y axis can be shorter than the length L151 of the first film layer 151 along the Y axis (L151>L152). Also, the length W152 of the second film layer 152 along the X axis can be shorter than the length W151 of the first film layer 151 along the X axis of the conductor 14 (W151>W152).

[0067] By making the length along the X-axis and the length along the Y-axis of second film layer 152 shorter than those of first film layer 151, it is possible to increase the exposed area of ​​first film layer 151. Therefore, when applied to battery 10, it is possible to particularly improve the adhesion between exterior body 11 and insulating resin film 15 of battery 10, while adjusting the operating pressure, which is the pressure at which gas inside exterior body 11 is exhausted to the outside.

[0068] Moreover, the first film layer 151 and the second film layer 152 can be disposed so that the positions on the Y axis of one side of each of them coincide with each other.

[0069] 2, side 152A of second film layer 152 and side 151A of first film layer 151 are disposed so as to coincide with each other in position on the Y axis. In the case of this configuration example, side 152B of second film layer 152 and side 151B of first film layer 151 do not coincide with each other in position on the Y axis.

[0070] For example, when the lead 13 is applied to a battery, if the second end region 22 of the conductor 14 is disposed so as to be located inside the exterior body 11, the side 152A of the second film layer 152 and the side 151A of the first film layer 151 will be disposed inside the exterior body 11. Therefore, when the pressure inside the exterior body 11 increases, the side 152A, which is one side of the second film layer 152, can directly contact the gas generated inside the exterior body 11 and is easily cleaved. Therefore, when the pressure inside the exterior body 11 increases, the reactivity to the pressure is increased, and when the pressure inside the exterior body 11 reaches a desired pressure, the gas inside the exterior body 11 can be discharged to the outside. (Second configuration example) For example, as shown in FIG. 4, the length L151 of the first film layer 151 along the Y axis minus the length L152 of the second film layer 152 along the Y axis (L151-L152) can be greater than or equal to 0 mm and less than or equal to 1 mm.

[0071] That is, for example, L151=L152 may be satisfied as shown in FIG. 4, and the length L152 of the second film layer 152 may be shorter than the length L151 of the first film layer 151 within a range of up to 1 mm.

[0072] In this case, the length W152 of the second film layer 152 along the X-axis is shorter than the length W151 of the first film layer 151 along the X-axis, i.e., W152 <W151にできる。

[0073] 1, when the lead 13 is applied to a battery, the exterior body 11 is disposed so as to cover a portion of the first film layer 151 along the Y axis. Therefore, when the length L152 of the second film layer 152 along the Y axis is set to be the same as the length L151 of the first film layer 151, the second film layer 152 can be disposed so as to connect the inside and outside of the exterior body 11 of the battery 10. As a result, when the pressure inside the exterior body 11 increases, the operating pressure, which is the pressure at which gas inside the exterior body 11 is exhausted to the outside, can be reduced.

[0074] The effect of L151>L152 has already been explained.

[0075] In addition, the first film layer 151 and the second film layer 152 can be disposed so that the positions on the Y axis of one side of each of them coincide with each other.

[0076] In the embodiment shown in FIG. 4, side 152A of second film layer 152 and side 151A of first film layer 151 are disposed so that their positions on the Y axis coincide with each other.

[0077] The effect is the same as in the first configuration example, and therefore a description of the effect will be omitted. (Third configuration example) For example, as shown in FIG. 5, the second film layer 152 may have sides located at both ends along the Y axis that have different lengths.

[0078] In the example shown in FIG. 5, the second film layer 152 has a length W1521 of the side 152A located at both ends of the Y axis and a length W1522 of the side 152B that are different from each other. <W1521となっている。

[0079] By configuring the second film layer 152 so that the sides located at both ends of the Y axis have different lengths, it is possible to adjust the responsiveness to pressure within the exterior body 11 and the ease with which gas within the exterior body 11 can be released to the outside.

[0080] When applied to a battery, if the length W1521 of side 152A arranged inside exterior body 11 is made longer than the length W1522 of side 152B, the adhesive force at the end portion where insulating resin film 15 located inside exterior body 11 contacts exterior body 11 will be smaller than when sides 152A and 152B are both the same as length W1522 of side 152B. This makes it possible to lower the operating pressure, which is the pressure at which gas inside exterior body 11 is exhausted to the outside when the pressure inside exterior body 11 increases.

[0081] The length W1521 of side 152A and the length W1522 of side 152B can be selected according to the required operating pressure and are not particularly limited.

[0082] The length L152 of the second film layer 152 along the Y axis is not particularly limited. For example, similar to the first configuration example, the length L152 of the second film layer 152 along the Y axis of the conductor 14 may be shorter than the length L151 of the first film layer 151 along the Y axis of the conductor 14 (L151>L152). Also, similar to the second configuration example, the length obtained by subtracting the length L152 of the second film layer 152 along the Y axis from the length L151 of the first film layer 151 along the Y axis may be set to be 0 mm or more and 1 mm or less.

[0083] In addition, the first film layer 151 and the second film layer 152 can be disposed so that the positions on the Y axis of one side of each of them coincide with each other.

[0084] In the embodiment shown in FIG. 4, side 152A of second film layer 152 and side 151A of first film layer 151 are disposed so that their positions on the Y axis coincide with each other.

[0085] The effect is the same as in the first configuration example, and therefore a description of the effect will be omitted. EXAMPLES

[0086] The present invention will be described below with reference to specific examples, but is not limited to these examples. (Evaluation method) First, the evaluation methods for the leads and batteries produced in the following experimental examples will be described.

[0087] A tube was connected to the exterior body 11 of the battery produced in the following experimental example, and air was supplied through the tube at a constant pressure and flow rate into the interior of the exterior body 11. The pressure inside the tube was measured at this time, and the pressure at the point when the air was discharged from the exterior body 11 and the increase in the pressure inside the tube stopped was evaluated as the operating pressure.

[0088] In addition, soapy water was sprayed around the exterior body 11 of the battery, and the location where the air was discharged was observed.

[0089] The leads and batteries in each experimental example will be described below.

[0090] Experimental Examples 1 to 3 are working examples, and Experimental Example 4 is a comparative example. In all of Experimental Examples 1 to 4, first insulating resin film 15A and second insulating resin film 15B had the same configuration. [Experimental Example 1] 2 and 3A was produced, and a battery 10 was produced using two of the leads 13. The first film layer 151 has two layers, from the position closest to the conductor 14, a base layer 151a containing maleic anhydride modified polypropylene and a surface layer 151b containing polypropylene.

[0091] The exterior body 11 used was a laminate film in which the first resin layer 111 and the second resin layer 113 were polypropylene films and the metal layer 112 was aluminum foil.

[0092] In this experimental example, the positions of lead 13 and exterior body 11 were adjusted so that second film layer 152 was completely covered by exterior body 11.

[0093] 1, exterior body 11 was arranged so as to cover a part of insulating resin film 15 of lead 13, and was thermally welded to form seal portion 110. At this time, a tube for supplying air during evaluation was placed on one side where lead 13 was not arranged.

[0094] Since the device was produced for evaluation purposes, the electrode stack 12 was not disposed within the exterior body 11.

[0095] When the above-mentioned evaluation was carried out on the obtained battery, it was confirmed that the operating pressure was 0.30 MPa and that air was discharged from the portion of the lead 13 where the second film layer 152 was provided. [Experimental Example 2] A lead and a battery were produced and evaluated under the same conditions as in Experimental Example 1, except that the lead 13 was formed in the form shown in FIG.

[0096] The lead 13 is configured so that the length L151 of the first film layer 151 and the length L152 of the second film layer 152 along the Y axis are the same.

[0097] In the battery produced in this experimental example, the positions of lead 13 and exterior body 11 were adjusted so that only a portion of second film layer 152 was covered by exterior body 11 .

[0098] When the above-mentioned evaluation was carried out on the obtained battery, it was confirmed that the operating pressure was 0.05 MPa and that air was discharged from the portion of the lead 13 where the second film layer 152 was provided. [Experimental Example 3] A lead and a battery were produced and evaluated under the same conditions as in Experimental Example 1, except that the lead 13 was formed in the form shown in FIG.

[0099] The length L152 of the second film layer 152 along the Y axis is configured to be shorter than the length L151 of the first film layer 151 along the Y axis of the conductor 14, that is, L151>L152.

[0100] Furthermore, in the battery produced in this experimental example, the positions of lead 13 and exterior body 11 were adjusted so that second film layer 152 was completely covered by exterior body 11 .

[0101] When the above-mentioned evaluation was carried out on the obtained battery, it was confirmed that the operating pressure was 0.20 MPa and that air was discharged from the portion of the lead 13 where the second film layer 152 was provided. [Experimental Example 4] A lead and a battery were produced and evaluated under the same conditions as in Experimental Example 1, except that the insulating resin film 15 was composed only of the first film layer 151 and the second film layer 152 was not provided.

[0102] The above-mentioned evaluation was carried out on the obtained battery, and since air was not discharged even when the pressure reached 0.5 MPa, the evaluation was stopped at this pressure. [Explanation of symbols]

[0103] 10 batteries 11 Exterior body 12 Electrode laminate 13 Lead 14 Conductor Side 14A 14B side 14C side 14D Side L14 Length W14 Length XX axis YY axis ZZ axis 15 Insulating resin film 15A First Insulating Resin Film 15B Second insulating resin film 21 First end region 22 Second end area 31 Block Arrow 110 Seal part 111 First resin layer 112 Metal layer 113 Second resin layer 141 Top surface 142 Bottom surface 151 First film layer 151a Base layer 151b Surface layer 151c middle class 1511 Exposed part Around 151A Around 151B L151 Length W151 Length 152 Second Film Layer 152A side 152B side L152 Length W152 Length W1521 Length W1522 Length

Claims

1. A plate-shaped conductor having rectangular upper and lower surfaces; a first insulating resin film disposed on the top surface of the conductor; a second insulating resin film disposed on the lower surface of the conductor; When the conductor is viewed in the vertical direction of the upper surface, an axis along two selected opposing sides is defined as an X-axis, and an axis perpendicular to the X-axis is defined as a Y-axis, the first insulating resin film and the second insulating resin film are arranged so as not to cover both end portions of the conductor along the Y-axis, but to cover the conductor in a portion other than the both end portions along the X-axis, and to overlap each other when viewed along the vertical direction of the upper surface; At least one of the first insulating resin film and the second insulating resin film has a first film layer and a second film layer in this order from a position closest to the conductor, The second film layer is disposed so that a portion of a surface of the first film layer is exposed, and is made of a different type of resin from that of the first film layer.

2. the second film layer is shorter than the first film layer in both length along the X-axis and length along the Y-axis; The lead for a nonaqueous electrolyte battery according to claim 1 , wherein the first film layer and the second film layer are disposed so that positions on the Y axis of one side of the first film layer and the second film layer coincide with each other.

3. a length obtained by subtracting a length of the second film layer along the Y axis from a length of the first film layer along the Y axis is 0 mm or more and 1 mm or less; a length of the second film layer along the X-axis is less than a length of the first film layer along the X-axis; The lead for a nonaqueous electrolyte battery according to claim 1 , wherein the first film layer and the second film layer are disposed so that positions on the Y axis of one side of the first film layer and the second film layer coincide with each other.

4. The second film layer has sides each located on both ends of the Y axis that are different in length, The lead for a nonaqueous electrolyte battery according to claim 1 , wherein the first film layer and the second film layer are disposed so that positions on the Y axis of one side of the first film layer and the second film layer coincide with each other.

5. 5. The lead for a nonaqueous electrolyte battery according to claim 1, wherein the first film layer contains, as a resin, one or more types selected from the group consisting of polyolefin resin, polyester resin, polystyrene resin, and polyvinyl chloride resin.

6. 5. The lead for a nonaqueous electrolyte battery according to claim 1, wherein the second film layer contains, as a resin, at least one type selected from the group consisting of polyimide resin, polyester resin, and fluorine-based resin.

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