JP2017098205A - Secondary battery having electrode body - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a secondary battery capable of suppressing generation of internal short circuit caused by a foreign substance.SOLUTION: A secondary battery includes: an electrode body 20 configured by laminating a positive electrode, a negative electrode, and a separator interposed between the positive electrode and the negative electrode; and an internal member 200 arranged on the outside of the electrode body 20 in a lamination direction. The internal member 200 includes a first conductive member 110 conducted to the positive electrode; a second conductive member 120 conducted to the negative electrode; and an insulation member 130 interposed between the first conductive member 110 and the second conductive member 120. The first conductive member 110 is mutually stuck to at least an outer edge portion out of a face opposed to the insulation member 130 and the second conductive member 120 is mutually stuck to at least an outer edge portion out of a face opposed to the insulation member 130.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a secondary battery having an electrode body.

  With the development of technology and production related to mobile devices such as mobile phones and laptop computers, the demand for secondary batteries as energy sources is increasing. In particular, an increase in demand is expected in the future as a high-output power source for driving vehicles such as electric vehicles (EV), hybrid vehicles (HV), and plug-in hybrid vehicles (PHV).

  However, when the secondary battery is subjected to excessive penetration impact, such as when the battery container is crushed by an external impact, the separator between the positive and negative electrodes breaks and a short circuit occurs. There was a risk of heat generation.

  Therefore, in Patent Document 1, for example, an electrode having no active material layer (short-circuit electrode) and an insulating layer disposed between the short-circuit electrode and the outermost periphery of the electrode body are provided outside the electrode body in the battery container. A secondary battery provided has been proposed. According to this secondary battery, when a through impact is applied, heat generation is suppressed by forming a short-circuit path between the short-circuit electrode and either the positive electrode or the negative electrode closest to the outermost periphery of the electrode body. In addition, the safety of the secondary battery against penetration impact can be improved.

JP 2013-41824 A

  However, for example, when the battery components come into contact with each other due to external impact or when the battery container and the battery lid are welded, there is a possibility that conductive foreign matters such as fine metal pieces may be generated in the battery container. . In the prior art, the generated foreign matter may be mixed between the short-circuiting electrode and the insulating layer, and an internal short circuit may occur due to the mixed foreign matter penetrating the insulating layer. When an internal short circuit occurs, there is a possibility that the performance of the battery will deteriorate due to the short circuit current.

  Therefore, the present invention was created to solve the above-described conventional problems in secondary batteries, and an object thereof is to provide a secondary battery in which the occurrence of internal short circuits due to foreign substances is suppressed.

  In the secondary battery disclosed herein, an electrode body in which a positive electrode, a negative electrode, and a separator interposed between the positive electrode and the negative electrode are stacked, a battery container that houses the electrode body, and the electrode body And an internal member disposed between the electrode body and the battery container in the stacking direction. The internal member is interposed between the first conductive member connected to the positive electrode, the second conductive member connected to the negative electrode, and the first conductive member and the second conductive member. And an insulating member. Here, the first conductive member has at least outer edges bonded to each other among the surfaces facing the insulating member, and the second conductive member is the surface facing the insulating member. A secondary battery characterized in that at least outer edges are bonded to each other.

  According to such a configuration, foreign matter can be prevented from being mixed between the first conductive member and the insulating member and between the second conductive member and the insulating member, and an internal short circuit caused by the foreign matter can be generated. Can be suppressed.

  In a preferred embodiment of the secondary battery disclosed herein, either the first conductive member or the second conductive member is a battery container.

  According to such a configuration, since there is a space for filling the electrode body in the battery container by the thickness of the first conductive member or the second conductive member, a secondary battery with higher energy density can be obtained. Is possible.

  In a preferred embodiment of the secondary battery disclosed herein, the first conductive member is a positive electrode current collector foil, and the second conductive member is a negative electrode current collector foil.

  According to such a configuration, there is no need to prepare an internal member separately from the electrode body, and there is no need for a bonding portion between the electrode body and the internal member, so that a secondary battery with higher safety and high energy density is obtained. It is possible.

It is sectional drawing which shows typically the internal structure of the secondary battery processed in one Embodiment of this invention from the width direction of this secondary battery. It is sectional drawing which shows typically the internal structure of the secondary battery processed in one Embodiment of this invention from the thickness direction of this secondary battery. It is a schematic diagram which shows the whole structure of the electrode body of the secondary battery processed in one Embodiment of this invention. It is a schematic diagram which shows the adhesion state of the secondary battery in one Embodiment of this invention. It is sectional drawing which shows typically the internal structure of the secondary battery in one Embodiment of this invention from the width direction of this secondary battery. It is a schematic diagram which shows the structure of the secondary battery in one Embodiment of this invention.

  Hereinafter, typical embodiments of the secondary battery of the present invention will be described in detail with reference to the drawings. The embodiments described herein are, of course, not intended to limit the present invention in particular. Further, matters other than matters specifically mentioned in the present specification and necessary for the implementation of the present invention can be grasped as design matters for those skilled in the art based on the prior art in this field. Each drawing is schematically drawn. For example, the dimensional relationship (length, width, thickness, etc.) in each drawing does not reflect the actual dimensional relationship.

  First, the structure of the secondary battery 100 applied to this embodiment is demonstrated easily using FIG. 1 and FIG. In this specification, the “secondary battery” refers to a battery that is charged and discharged by the movement of electric charge between the positive and negative electrodes, and a typical example includes a lithium ion secondary battery. It is not limited to the secondary battery. Moreover, in this embodiment, although the example of a wound electrode body is shown, this invention is not restricted to this, You may use a laminated electrode body.

  In the secondary battery 100 shown in FIG. 1, roughly speaking, a battery having a flat rectangular shape in which a flat electrode body 20, a nonaqueous electrolyte (not shown), and an internal member 200 (not shown) are flat. The container (that is, the outer container) 30 is accommodated. The battery container 30 has a box-shaped (that is, bottomed rectangular parallelepiped) case body 32 having an opening at one end (corresponding to the upper end in a normal use state of the battery), and the opening of the case body 32 is sealed. And a lid 34 to be stopped. As a material of the battery container 30, for example, a light metal material having a good thermal conductivity such as aluminum, stainless steel, or nickel-plated steel can be preferably used.

  As shown in FIG. 2, the internal member 200 is interposed between the first conductive member 110, the second conductive member 120, and the first conductive member 110 and the second conductive member 120. And an insulating member 130. In addition, at least outer edge portions of the surfaces facing the first conductive member 110 and the insulating member 130 are bonded to each other, and the surface of the surface facing the second conductive member 120 and the insulating member 130 is bonded. At least the outer edges are bonded together. The outer edge portion will be described later together with the description of FIG.

  The material of the first conductive member 110 and the second conductive member 120 is not particularly limited as long as it has conductivity, but is preferably lightweight and has good thermal conductivity such as aluminum, stainless steel, and nickel-plated steel. Metal materials can be preferably used. The insulating member 130 may be made of polyethylene (PE) or polypropylene (PP), which is a polyolefin resin, polyphenylene sulfide (PPS), which is an engineering plastic, or perfluoroalkoxy fluororesin (PFA), which is a fluorinated resin copolymer. A single or composite synthetic resin can be used.

  Here, the first conductive member 110 and the second conductive member 120 are electrically connected (conductive) to the positive electrode 50 and the negative electrode 60, respectively. In the description of this embodiment and FIG. 2, the first conductive member 110 is described so as to be closer to the electrode body than the second conductive member 120. The positional relationship between the first conductive member 110 and the second conductive member 120 may be switched.

  As shown in FIG. 1, the lid 34 is set to release the internal pressure when the internal pressure of the battery container 30 rises above a predetermined level, and the positive terminal 42 and the negative terminal 44 for external connection. A thin safety valve 36 and an injection port (not shown) for injecting a non-aqueous electrolyte are provided. In addition, a current interruption mechanism (Current Interrupt Device, CID) that operates when the internal pressure of the battery container 30 increases may be provided inside the battery container 30.

  As shown in FIGS. 1 to 3, the electrode body 20 disclosed herein includes a positive electrode active material layer 54 along a longitudinal direction on one or both surfaces (here, both surfaces) of an elongated positive electrode current collector 52. The formed positive electrode 50 and the negative electrode 60 in which the negative electrode active material layer 64 is formed along the longitudinal direction on one side or both sides (here, both sides) of the long negative electrode current collector 62 are two long pieces. The laminated body laminated | stacked through the separator 70 of a shape is wound by the elongate direction, and has the form shape | molded by the flat shape.

  As shown in FIG. 1 and FIG. 3, the winding core portion (that is, the positive electrode active material layer 54 of the positive electrode 50 and the negative electrode active material layer 64 of the negative electrode 60) , A laminated structure in which separators 70 are laminated). In addition, at both ends of the electrode body 20 in the winding axis direction, a part of the positive electrode active material layer non-formed part 52a and a part of the negative electrode active material layer non-formed part 62a protrude outward from the wound core part. The positive electrode side protruding portion (positive electrode active material layer non-forming portion 52a) and the negative electrode side protruding portion (negative electrode active material layer non-forming portion 62a) are respectively provided with a positive electrode current collecting plate 42a and a negative electrode current collecting plate 44a. The terminal 42 and the negative terminal 44 are electrically connected to each other.

Examples of the positive electrode current collector 52 constituting the positive electrode 50 include an aluminum foil. The positive electrode active material layer 54 contains at least a positive electrode active material. Examples of the positive electrode active material include lithium composite metal oxides such as a layered structure and a spinel structure (for example, LiNi _1/3 Co _1/3 Mn _1/3 O ₂ , LiFePO _4, etc.). The positive electrode active material layer 54 can include components other than the active material, for example, a conductive material such as acetylene black (AB), a binder such as polyvinylidene fluoride (PVDF), and the like.

  Examples of the negative electrode current collector 62 constituting the negative electrode 60 include copper foil. The negative electrode active material layer 64 contains at least a negative electrode active material. Examples of the negative electrode active material include carbon materials such as graphite. The negative electrode active material layer 64 may include components other than the active material, for example, a binder such as styrene butadiene rubber (SBR), a thickener such as carboxymethyl cellulose (CMC), and the like.

  Such a positive electrode 50 and a negative electrode 60 can be produced as follows, for example. First, a positive electrode active material or a negative electrode active material and a material used as necessary are combined with an appropriate solvent (for example, an organic solvent such as N-methyl-2-pyrrolidone for a positive electrode active material, or ion exchange for a negative electrode active material A paste-like (slurry) composition is prepared by dispersing in an aqueous solvent such as water. Next, an appropriate amount of the composition can be applied to the surface of the positive electrode current collector 52 or the negative electrode current collector 62, and then the solvent can be removed by drying. Moreover, the properties (for example, average thickness, active material density, porosity, etc.) of the positive electrode active material layer 54 and the negative electrode active material layer 64 can be adjusted by performing an appropriate press treatment as necessary.

  The separator 70 is, for example, a sheet (film) made of a resin such as polyethylene (PE), polypropylene (PP), polyester, cellulose, or polyamide. Such a sheet may have a single-layer structure or a laminated structure of two or more layers (for example, a three-layer structure in which PP layers are laminated on both sides of a PE layer). Further, a heat resistant layer (HRL) may be provided on the surface of the separator 70.

As the nonaqueous electrolytic solution, typically, an organic solvent (nonaqueous solvent) containing a supporting salt can be used. As the non-aqueous solvent, organic solvents such as various carbonates, ethers, esters and the like used for an electrolyte solution of a general lithium ion secondary battery can be used without particular limitation. As specific examples, ethylene carbonate (EC), propylene carbonate (PC), diethyl carbonate (DEC) and the like can be used alone or in appropriate combination of two or more. As the supporting salt, for example, a lithium salt such as LiPF ₆ , LiBF ₄ , or LiClO ₄ can be suitably used.

  The non-aqueous electrolyte includes components other than the non-aqueous solvent and the supporting salt described above, for example, a gas generating agent such as biphenyl (BP) and cyclohexylbenzene (CHB); an oxalato complex containing a boron atom and / or a phosphorus atom. Various additives such as a compound, a film forming agent such as vinylene carbonate (VC), fluoroethylene carbonate (FEC); a dispersant; a thickener;

  EXAMPLES Examples (test examples) relating to the present invention will be described below, but the present invention is not intended to be limited to those shown in the examples (test examples).

The electrode bodies according to the first example 1 and the second example were constructed by the following materials and processes.
<First embodiment>
The positive electrode was produced by the following procedure. LiNi _0.33 Co _0.33 Mn _0.33 O ₂ (LNCM) as a positive electrode active material powder, AB as a conductive material, and PVDF as a binder, LNCM: AB: PVDF = 90: 8: 2 A slurry-like composition for forming a positive electrode active material layer was prepared by mixing with NMP at a mass ratio of The composition was coated on both sides of a 15 μm long aluminum foil (positive electrode current collector) in a strip shape, dried and pressed to prepare a positive electrode sheet. The coating amount of the positive electrode active material layer forming composition and the pressing conditions were adjusted so that the average thickness of the positive electrode was about 65 μm (the average thickness per one side of the positive electrode active material layer was about 25 μm).

  The negative electrode was produced according to the following procedure. First, graphite (C) whose surface was coated with amorphous carbon was prepared as a negative electrode active material powder. And this graphite (C), SBR as a binder, and CMC as a thickener are mixed with ion exchange water at a mass ratio of C: SBR: CMC = 98: 1: 1, A composition for forming a negative electrode active material layer was prepared. The composition was coated on both sides of a long copper foil (negative electrode current collector) having a thickness of 10 μm and dried and pressed to prepare a negative electrode sheet. The amount of the negative electrode active material layer-forming composition applied and the pressing conditions were adjusted so that the average thickness of the negative electrode was about 80 μm (the average thickness per one side of the negative electrode active material layer was about 35 μm).

  The positive electrode and the negative electrode produced as described above have a four-layer structure in which a polypropylene layer is formed on both sides of a polyethylene layer, and a layer (so-called heat-resistant layer) made of alumina particles and a binder is formed on the surface of one polypropylene layer. The sheets were overlapped in the longitudinal direction through two separators, and wound up (wound) 60 times in the longitudinal direction (that is, the number of times of winding). Then, the flat-shaped electrode body was produced by crushing such (the positive electrode, the negative electrode and the separator after winding) in one direction perpendicular to the winding axis.

  Next, as shown in FIG. 4, as the internal member 200, an aluminum foil having a thickness of 15 μm (first conductive member 110), a PE sheet having a thickness of 5 mm (insulating member 130), and a copper foil having a thickness of 10 μm (first member). Two conductive members 120), and cut out at a length of one or more circumferences in the direction perpendicular to the winding axis of the electrode body, and then the first conductive member 110 and the insulating member 130 face each other. The first conductive member 110, the insulating member 130, and the second conductive member 120 were bonded together by leaving a portion 5 mm from the outer peripheral edge at 150 ° C. and a pressure of 0.1 MPa for 1 hour. .

  In this embodiment, heat welding is used as the bonding method, but other bonding methods such as using an adhesive may be used. Further, in this embodiment, the length of the internal member 200 is set to a length equal to or longer than one circumference of the outer periphery in the direction orthogonal to the winding axis of the electrode body, and the adhesion location is set to 10 mm from the outer circumference end. For example, only the outer peripheral end of the insulating member 130 or the entire surface may be used as long as the effect of the invention is obtained. Further, the step of bonding the first conductive member 110 and the insulating member 130 and the step of bonding the second conductive member 120 and the insulating member 130 may be performed separately.

  Next, the internal member 200 in which the first conductive member 110, the insulating member 130, and the second conductive member 120 are stacked in this order is disposed between the electrode body and the battery container 30 in the stacking direction of the electrode body. The electrode body positive electrode 50 and the first conductive member 110 are electrically connected (conductive), and the electrode body negative electrode 60 and the second conductive member 120 are electrically connected (conductive). Fixed to each.

  In the present embodiment, as an electrical connection method, the negative electrode 60 and the first conductive member 110 are fixed by the first connection member 112 as shown in FIG. 5, and the positive electrode 50 and the second conductive member 120 are secondly connected. However, the present invention is not limited to the fixing method, and may be fixed using other methods such as using a conductive adhesive. The first connecting member 112 and the second connecting member 121 are not particularly limited as long as they are conductive materials, and this time, aluminum foil was used.

A positive electrode lead terminal and a negative electrode lead terminal were respectively attached to the non-formed part of the positive electrode active material layer and the non-formed part of the negative electrode active material layer of the electrode body by ultrasonic welding means. Thereafter, the electrode body and the internal member 200 were accommodated in the box-shaped battery container 30 together with the non-aqueous electrolyte, and the opening of the battery container 30 was hermetically sealed. As the non-aqueous electrolyte, 41 g of a non-aqueous electrolyte in which LiPF ₆ as a supporting salt is contained at a concentration of about 1 mol / liter in a mixed solvent containing EC, DMC, and EMC in a volume ratio of 3: 4: 3 is used. did. The sealed prismatic lithium ion secondary battery thus constructed was subjected to an initial charge / discharge treatment (conditioning) by a conventional method to produce a secondary battery.

According to such a configuration, foreign matter can be prevented from being mixed between the first conductive member 110 and the insulating member 130 and between the second conductive member 120 and the insulating member 130. It is possible to suppress the occurrence of an internal short circuit.
<Second embodiment>
A schematic diagram of the second embodiment is shown in FIG. The battery of the second embodiment has the same configuration as that of the first embodiment except that the configuration of the internal member 200 is different and that the positive electrode of the electrode body is electrically connected to the battery container 30. A duplicate description is omitted.

  The internal member 200 is made by stacking a PE sheet (insulating member 130) having a thickness of 5 mm and a copper foil (second conductive member 120) having a thickness of 10 μm, and the winding axis of the electrode body and The second conductive member 120 and the insulating member 130 were bonded to each other after cutting out at a length equal to or longer than one round of the outer periphery in the orthogonal direction. Thereafter, the insulating member 130 and the battery container 30 were bonded. Although the bonding method and the bonding location are the same as those in the first embodiment, they are omitted, but are not limited thereto.

  The positive electrode of the electrode body was electrically connected to the battery container 30 using an aluminum foil having a thickness of 15 μm. In this embodiment, an aluminum foil is used separately from the positive electrode, but the positive electrode and the battery container 30 may be electrically connected by extending the aluminum foil of the positive electrode current collector foil. You may electrically connect using the material of.

  Next, counting from the inner peripheral direction of the wound body, the inner member 200 in which the second conductive member 120 and the insulating member 130 are laminated in this order forms the outermost periphery of the wound electrode body. The negative electrode 60 of the electrode body and the second conductive member 120 were fixed so as to be electrically connected. In this embodiment, the negative electrode 60 of the electrode body and the second conductive member 120 are fixed by being welded by the second connecting member 122, respectively, but the present invention is not limited to the fixing method. It may be fixed using other methods such as using a conductive adhesive. The second connecting member 121 is not particularly limited as long as it is a conductive material, and an aluminum foil is used this time.

  Further, the insulating member 130 of the internal member 200 fixed to the electrode body and the battery container 30 were fixed in a contacted state. In this embodiment, fixing is performed using a conductive adhesive, but the method is not limited to this fixing method.

With this configuration, the second embodiment has a space for filling the electrode body in the battery container 30 by the thickness of the first conductive member 110 as compared with the first embodiment, so that a secondary battery with higher energy density is produced. I can do it.
<Third embodiment>
The battery of the third embodiment has the same configuration as that of the first embodiment except that the configuration of the internal member 200 is different and that the negative electrode of the electrode body is electrically connected to the battery container 30. A duplicate description is omitted.

  The internal member 200 is produced by stacking a 15 μm thick aluminum foil (first conductive member 110) and a 5 mm thick PE sheet (insulating member 130), and is orthogonal to the winding axis of the electrode body. The outer edge portion 111 of the first conductive member and the insulating member 130 were bonded to each other after cutting out at a length equal to or longer than one circumference of the outer periphery in the direction to be performed. Thereafter, the insulating member 130 and the battery container 30 were bonded. Although the bonding method and the bonding location are the same as those in the first embodiment, they are omitted, but are not limited thereto.

  The negative electrode of the electrode body was electrically connected to the battery container 30 using a copper foil (second connecting member 122) having a thickness of 10 μm. In this example, copper foil was used separately from the negative electrode, but the positive electrode and the battery container 30 may be electrically connected by extending the copper foil of the positive electrode current collector foil. You may electrically connect using the material of.

  Next, the internal member 200 in which the first conductive member 110 and the insulating member 130 are stacked in this order, counting from the inner peripheral direction of the wound body, is arranged to constitute the outermost periphery of the electrode body, and the positive electrode of the electrode body 50 and the first conductive member 110 were fixed so as to be electrically connected to each other. In the present embodiment, fixing is performed using a conductive adhesive, but the fixing method is not limited thereto.

  Further, the insulating member 130 of the internal member 200 fixed to the electrode body and the battery container 30 were fixed in a contacted state. In this embodiment, fixing is performed using a conductive adhesive, but the method is not limited to this fixing method.

With this configuration, the third embodiment has a space for filling the electrode body in the battery container 30 by the thickness of the second conductive member as compared with the first embodiment, so that a secondary battery having a higher energy density is produced. I can do it.
<Fourth embodiment>
Since the battery of the fourth embodiment has the same configuration as that of the first embodiment except that the internal member 200 is integral with the electrode body, the overlapping description is omitted.

  In this example, the positive electrode is composed of a power generation part having a positive electrode active material layer and a positive electrode current collector foil part that does not have a positive electrode active material layer and the positive electrode current collector foil is exposed. The outermost peripheral part is not a power generation part but a positive electrode current collector foil part.

  The negative electrode is also composed of a power generation part having a negative electrode active material layer and a negative electrode current collector foil part that does not have a negative electrode active material layer and the negative electrode current collector foil is exposed. It is comprised from the negative electrode current collector foil part instead of a power generation part.

  The positive electrode and the negative electrode described above were wound in the longitudinal direction through two separators having a four-layer structure in the same manner as in the first example, and then wound to prepare an electrode body. And the winding outermost periphery part of the electrode body fixed the positive electrode current collection foil part and the negative electrode current collection foil part via the separator. In this example, the positive electrode current collector foil part and the separator and the negative electrode current collector foil part and the separator were fixed by welding the separator of the electrode body, but the method is not limited to this fixing method.

  With such a configuration, the fourth embodiment does not require a portion for bonding the electrode body 20 and the internal member 200, and the ratio of the internal member 200 to the battery container 30 tends to be small. Therefore, it is easy to create a space for filling the electrode body, and a secondary battery with higher energy density can be manufactured. In addition, since there is no need to connect the first external member and the second external member to the positive electrode or the negative electrode, manufacturing is easy and there is a merit in terms of cost.

  Specific examples of the present invention have been described in detail above, but these are merely examples and do not limit the scope of the claims. The technology described in the claims includes various modifications and changes of the specific examples illustrated above.

  Moreover, in the said Example, although the square battery which has metal packages was employ | adopted, it is not restricted to this form. For example, a square battery or a cylindrical battery having a metal package, a battery having a laminate film package, or a battery having a synthetic resin package may be used.

  In the battery of the above embodiment, the power generation region and the exposed region of the positive electrode sheet are both made of aluminum, but both need not be made of aluminum. When applied to a general lithium secondary battery, aluminum excellent in stability at a high potential is preferable.

  In the negative electrode sheet, both the power generation area and the exposed area are made of copper, but both need not be made of copper. These metal foils constituting the electrodes can be used without particular limitation as long as they are conductive metals. For example, metal materials such as aluminum, copper, titanium, nickel, iron, and stainless steel can be used.

  The technical elements described in the present specification or the drawings exhibit technical usefulness alone or in various combinations, and are not limited to the combinations described in the claims at the time of filing. In addition, the technology exemplified in this specification or the drawings achieves a plurality of objects at the same time, and has technical usefulness by achieving one of the objects.

DESCRIPTION OF SYMBOLS 20 Electrode body 30 Battery container 32 Battery container main body 34 Cover body 36 Safety valve 42 Positive electrode terminal 42a Positive electrode current collector plate 44 Negative electrode terminal 44a Negative electrode current collector plate 50 Positive electrode 52 Positive electrode current collector 52a Positive electrode active material layer non-formation part 54 Positive electrode active material Layer 60 Negative electrode 62 Negative electrode current collector 62a Negative electrode active material layer non-formed portion 64 Negative electrode active material layer 70 Separator 100 Secondary battery 110 First conductive member 111 Outer edge portion 112 of first conductive member First connection member 120 First Second conductive member 121 Outer edge portion 122 of second conductive member Second connection member 130 Insulating member 131 Outer edge portion 200 of insulating member Internal member

Claims (3)

An electrode body in which a positive electrode, a negative electrode, and a separator interposed between the positive electrode and the negative electrode are stacked, and an internal member disposed outside in the stacking direction of the electrode body,
The internal member is interposed between the first conductive member connected to the positive electrode, the second conductive member connected to the negative electrode, and the first conductive member and the second conductive member. A secondary battery having an insulating member,
Of the surface facing the insulating member, the first conductive member has at least outer edges bonded to each other,
In the secondary battery, the second conductive member has at least outer edges bonded to each other on a surface facing the insulating member.   The secondary battery according to claim 1, wherein either the first conductive member or the second conductive member is a battery container. The first conductive member is a positive electrode current collector foil;
The secondary battery according to claim 1, wherein the second conductive member is a negative electrode current collector foil.