JP2009181899A - Laminated battery - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a laminated battery capable of suppressing drop in battery performance caused by penetration of moisture or the like into the battery and cutting of a current collecting tab even when outside force is applied while suppressing great rising of a production cost. <P>SOLUTION: The laminated battery has a laminated electrode body 10 formed by alternately laminating each of a plurality of positive electrode plates 1 from each of which a positive current collecting tab 11 is extended and each of a plurality of negative electrode plates 2 from each of which a negative current collecting tab 12 is extended through a separator 3. The positive current collecting tab 11 is joined to a positive current collecting terminal 15 in a piled-up state; the negative current collecting tab 12 is joined to a negative current collecting terminal 16 in a piled-up state. These current collecting terminals 15, 16 are projected from a laminate outer packaging 25, and an insulating resin layer 20 covering at least part of the positive current collecting tab 11 is formed in the positive current collecting tab 11. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a stacked battery used in, for example, a robot, an electric vehicle, a backup power supply, and the like, and more particularly to a stacked lithium ion battery capable of improving charge / discharge characteristics at a high rate.

  In recent years, batteries have been used not only for power sources of mobile information terminals such as mobile phones, notebook personal computers, and PDAs, but also for robots, electric vehicles, backup power sources, etc., and further increase in capacity is required. It has become like this. In response to such demands, lithium ion batteries have a high energy density and high capacity, and are therefore widely used as drive power sources as described above.

  Battery types of such a lithium ion battery are roughly classified into a cylindrical type in which a spiral electrode body is enclosed in a bottomed cylindrical exterior body, and a laminated electrode body in which a plurality of rectangular electrodes are stacked. There is a laminated type encapsulated in a rectangular outer package or a laminate outer package produced by welding two laminated films.

  Among these lithium ion batteries, the specific configuration of the laminated electrode body of the laminated battery in which the laminated electrode body is enclosed in a laminated outer package has a sheet-like positive electrode plate having a positive electrode current collecting tab and a negative electrode current collecting tab. A sheet-like negative electrode plate is laminated in a required number via a separator.

  Here, as described above, since the lithium ion battery has a high capacity and high output, if an internal short circuit occurs in a part of the laminated electrode, a large current may flow from the laminated electrode to the short-circuited portion. When flowing in, the lithium ion battery itself has a defect such as damage, and the lithium ion battery itself generates heat, which causes inconvenience of releasing a large amount of heat to the surroundings.

Considering this, the current collector tab is used as a fuse portion, and the cross-sectional area of the fuse portion is defined as the current collector resistivity (μΩ · mm) × positive electrode area (mm ² ) × 4.27 × 10. ^-7 <Fuse section cross-sectional area (mm ² ) <current collector resistivity (μΩ · mm) × positive electrode area (mm ² ) × 2.41 × 10 ⁻⁶ See Patent Document 1 below).

  In addition, in order to improve the safety of the battery, the PTC element is connected in series to the current collecting tab attached to the winding start portion of either the positive electrode or the negative electrode of the battery provided with the spiral electrode body, A battery in which the PTC element is positioned inside the battery element has been proposed (see Patent Document 2 below).

Japanese Patent Laid-Open No. 08-185850 JP 2002-110137 A

  Here, in the technique described in Patent Document 1, when an abnormal current flows due to an internal short circuit or the like, the current collecting tab of the portion where the abnormal current flows is melted, so that the safety of the battery can be ensured to some extent. However, since the melted current collecting tab is in an exposed state, if the current collecting tab comes into contact with the adjacent current collecting tab, an abnormal current flows from the adjacent current collecting tab, and the battery generates heat. There are things to do. In addition, the melted current collecting tab and the aluminum layer of the laminate outer body come into contact with each other, and the aluminum is corroded. As a result, moisture or the like may enter the battery and the battery performance may be deteriorated. Furthermore, since the current collecting tab is foil-like, the strength is small, and the lead portion may be cut when an external force is applied. In addition, since the laminate exterior body has a resin layer formed on both surfaces of the metal layer, it is considered that the current collecting tab and the aluminum layer of the laminate exterior body are not in direct contact. However, since the resin layer may have scratches, voids, cracks, etc., there are portions where the resin is missing. Therefore, direct contact between the melted current collecting tab and the aluminum layer of the laminate outer package may occur.

  In the technique described in Patent Document 2, the presence of the PTC element can ensure the safety of the battery when an abnormal current flows due to an internal short circuit or the like. However, in order to apply this technique to a stacked battery, It is necessary to connect a PTC element to each current collecting tab, which complicates the manufacturing process of the battery and increases the manufacturing cost.

  The present invention takes the above-mentioned problems into consideration, and while suppressing a significant increase in manufacturing cost, the battery generates heat, or the battery performance is reduced due to moisture or the like entering the battery, and An object of the present invention is to provide a stacked battery that can prevent the current collector tab from being cut even when an external force is applied.

  In order to achieve the above object, the present invention provides a plurality of positive electrode plates each extending from a positive electrode current collecting tab and a plurality of negative electrode plates each extending from a negative electrode current collecting tab, alternately through separators. The laminated electrode body has a laminated electrode body, the laminated electrode body is disposed in a housing space of the exterior body, and the positive electrode current collecting tab is joined to the positive electrode current collecting terminal in an overlapping state, and the negative electrode current collecting tab is In a stacked battery that is joined to the negative electrode current collector terminal in an overlapping state and both the current collector terminals protrude from the outer package, at least one of the current collector tabs includes at least one of the current collector tabs. An insulating layer covering the portion is formed.

  In general, it is known that when a current flows through the current collecting tab, the current collecting tab generates heat, and when a current (abnormal current) of a predetermined current value or more flows, the current collecting tab is blown by large heat generation. Therefore, if an insulating layer covering at least a part of the current collecting tab is formed as in the above configuration, the portion where the insulating layer is present is inferior in heat dissipation than the portion where the insulating layer is not present. Increase in the temperature of the site where is present. As a result, when an abnormal current flows, the current collecting tab is melted at a portion where the insulating layer exists.

  In this way, when the current collecting tab is melted at the site where the insulating layer is present, the current collecting tab at the melted portion is covered with the insulating layer (the current collecting tab is not exposed). Even if the tab is deformed in the direction of the adjacent current collecting tab after being melted, the melted current collecting tab and the adjacent current collecting tab are not electrically connected. Accordingly, it is possible to prevent the battery from generating heat due to an abnormal current flowing from the adjacent current collecting tab. Further, since the strength of the foil-like current collecting tab is increased to some extent due to the presence of the insulating layer, it is possible to suppress the current collecting tab from being cut when an external force is applied.

As said exterior body, the laminate exterior body formed by joining the periphery of two laminate films provided with the metal layer and the resin layer, or one laminate film provided with the metal layer and the resin layer It is desirable to use a laminate outer body formed by folding back and joining the peripheral edges.
When a laminated outer package is used as the outer package, even if the melted current collecting tab is deformed in the direction of the laminated outer package, the fused current collecting tab is covered with an insulating layer. The aluminum layer is not electrically connected. Therefore, it is possible to suppress the occurrence of inconveniences such as moisture entering into the battery and lowering the battery performance due to corrosion of the aluminum.

The insulating layer is preferably made of an insulating resin, and in particular, a polytetrafluoroethylene resin is preferably used as the insulating resin.
In general, the insulating resin is inexpensive and can be easily applied. In consideration of such points, polytetrafluoroethylene resin is more preferable.
However, the material for forming the insulating layer of the present invention is not limited to the insulating resin, and for example, a gel adhesive containing SiO ₂ or TiO ₂ may be used. The insulating resin is not limited to polytetrafluoroethylene resin, and may be an epoxy resin or the like.

It is desirable that the insulating layer integrally covers the current collecting tab in the superimposed state.
Although a resin layer can be formed on each current collecting tab, the effect of the present invention can be exhibited even if an insulating layer is formed so as to integrally cover the current collecting tabs in a superimposed state. In this case, the insulating layer can be formed in a shorter time than forming the resin layer on each current collecting tab.
In addition, since the cut current collecting tab is prevented from being deformed in the direction of the adjacent current collecting tab or the laminate outer package, the above-described effects are further exhibited.

Among the current collecting tabs on which the insulating layer is formed, the resin layer is formed on the current collecting tab located closest to the laminate outer package from the junction with the current collecting terminal to the electrode plate. It is desirable that
When a force is applied from the outside, the current collecting tab (hereinafter sometimes referred to as the outermost current collecting tab) present at the position closest to the laminate exterior body is subjected to a larger load than the other current collecting tabs, The outermost current collecting tab often cuts. Therefore, by forming a resin layer on the outermost current collecting tab from the junction with the current collecting terminal to the electrode plate, cutting of the outermost current collecting tab is suppressed.

It is desirable that the positive electrode active material used for the positive electrode plate and the negative electrode active material used for the negative electrode plate are made of a material capable of occluding and releasing lithium.
In a lithium ion battery in which the positive electrode active material and the negative electrode active material are made of a material capable of occluding and releasing lithium, problems such as heat generation are particularly likely to occur, so the effect of applying the configuration of the present invention is great.

  According to the present invention, since the current collecting tab is melted at the portion where the insulating layer is present, even if the melted current collecting tab is deformed in the direction of the adjacent current collecting tab, the current collecting tab is adjacent to the melted current collecting tab. The current collector tab is not electrically connected. Therefore, the heat generation of the battery due to the abnormal current flowing through the adjacent current collecting tab can be suppressed. Further, since the strength of the foil-like current collecting tab is increased to some extent due to the presence of the insulating layer, there is an excellent effect that the current collecting tab can be prevented from being cut when an external force is applied.

  Hereinafter, a stacked battery (rectangular lithium ion battery) according to an example of the present invention will be described with reference to FIGS. The laminated battery according to the present invention is not limited to those shown in the following embodiments, and can be implemented with appropriate modifications within a range not changing the gist thereof.

(Structure of stacked battery)
As shown in FIG. 1, the laminated battery has a laminated electrode body 10, and this laminated electrode body 10 is composed of two separators, a bag-like separator 3 having a positive electrode plate 1 disposed therein, and a negative electrode plate. 2 is laminated, and the negative electrode plate 2 is arranged at the outermost position. Thus, since the negative electrode plate 2 is arranged at the outermost position, the number of the negative electrode plates 2 is configured to be one more than the number of the positive electrode plates 1 (specifically, the positive electrode plate 1 is 50 sheets and 51 negative electrode plates 2). Although not shown, a polypropylene shape holding sheet is disposed outside the negative electrode plate 2 located at the outermost position. Also, as shown in FIG. A tape 5 for suppressing displacement of the electrode plates 1 and 2 is attached so as to straddle the laminated electrode body 10. Further, the laminated electrode body 10 is sealed together with an electrolytic solution in a storage space of a laminated exterior body 25 formed by welding two laminated films 28 as shown in FIG. From the body 25, a positive electrode current collecting terminal 15 made of an aluminum plate (thickness: 0.5 mm) and a negative electrode current collecting terminal 16 made of a copper plate (thickness: 0.5 mm) are projected. The laminate film 28 has a structure in which a resin layer is formed on both surfaces of an aluminum foil, and reference numeral 27 in FIG. 2 is a welded portion of the two laminate films 28.

As shown in FIG. 3A, the positive electrode plate 1 has a positive electrode active material made of LiCoO _{2 on} the entire surface of both sides of a positive electrode conductive core made of a rectangular aluminum foil (thickness: 15 μm). A positive electrode active material layer 1a composed of a conductive agent made of carbon black and a binder made of polyvinylidene fluoride is provided. The positive electrode plate 1 has a width L1 of 96 mm and a height L2 of 96 mm. From one side of the positive electrode plate 1, the positive electrode active material layer 1a is formed integrally with the positive electrode conductive core. The positive electrode current collection tab 11 (width L3 is 30 mm, height L4 is 20 mm) which is not provided has a structure protruding. The positive electrode current collecting tab 11 is welded to the positive electrode current collector terminal 15 in a state where the positive electrode current collector terminal 15 is overlaid on both surfaces of the positive electrode current collector terminal 15 (25 sheets on each surface of the positive electrode current collector terminal 15). Has been.

  As shown in FIG. 3C, the bag-like separator 3 is composed of two polypropylene (PP) separators 3a, and a fusion part 4 for fusing the separators 3a around each other in the peripheral part of the separators 3a. (Welding width is 2 mm). With such a configuration, the positive electrode plate 1 can be stored in the bag-like separator 3. As shown in FIG. 3B, the separator 3a has a rectangular shape with a height L5 of 100 mm, a width L6 of 100 mm, and a thickness of 30 μm.

  As shown in FIG. 4, the negative electrode plate 2 has a negative electrode active material made of natural graphite and polyvinylidene fluoride on both surfaces of a negative electrode conductive core made of a rectangular copper foil (thickness: 10 μm). The negative electrode active material layer 2a comprised from the binder which consists of is provided. The negative electrode plate 2 has a width L7 of 100 mm and a height L8 of 100 mm, which is the same size as the separator 3a. Further, from one side of the negative electrode plate 2, a negative electrode current collecting tab 12 that is integrally formed with the negative electrode conductive core and is not provided with the negative electrode active material layer 2a (width L9 is 30 mm, height L10 is 20 mm). ) Protrudes. The negative electrode current collecting tab 12 is overlaid on both surfaces of the negative electrode current collector terminal 16 (25 sheets on one surface of the negative electrode current collector terminal 16 and 26 sheets on the other surface). It is welded to the negative electrode current collector terminal 16.

  Here, as shown in FIGS. 6, 1, 3, and 5, an insulating resin layer 20 covering a part of the positive electrode current collecting tab 11 is formed on both surfaces of each positive electrode current collecting tab 11. The insulating resin layer 20 is formed of polytetrafluoroethylene resin. The insulating resin layer 20 has a thickness of about 30 μm on one side and a width L11 of 5 mm. FIG. 6 is a diagram schematically showing an actual structure in which adjacent insulating resin layers 20 are in contact with each other as shown in FIG. This is because the bipolar plates 1 and 2 and the separator 3 are extremely thin.

  As described above, if the insulating resin layer 20 is formed on the positive electrode current collecting tab 11, the portion where the insulating resin layer 20 exists is inferior in heat dissipation than the portion where the insulating resin layer 20 does not exist. In addition, the temperature rise in the portion where the insulating resin layer 20 exists is larger than the portion where the insulating resin layer 20 does not exist. As a result, as shown in FIG. 8 and FIG. 9, when an abnormality occurs in the cell 10a existing at the outermost position and an abnormal current flows through the positive electrode current collecting tab 11a corresponding to the cell 10a, FIG. As shown in FIG. 10, the positive electrode current collector tab 11 a is melted at a portion where the insulating resin layer 20 a of the positive electrode current collector tab 11 a is present.

  In this way, the positive electrode current collecting tab 11a is melted at a portion where the insulating resin layer 20a is present, and as shown in FIG. 8, the positive electrode current collecting tab 11a is deformed in the direction of the adjacent positive electrode current collecting tab 11b after the fusing. In this case, since the positive electrode current collecting tab 11a at the fusing part is covered with the insulating resin layer 20a (the positive electrode current collecting tab 11a is not exposed), the positive electrode current collecting tab adjacent to the fusing positive electrode current collecting tab 11a is used. The tab 11b is not electrically connected. Therefore, since an abnormal current can be prevented from flowing through the adjacent positive electrode current collecting tab 11b, the battery can be prevented from generating heat. Moreover, since the strength of the foil-shaped positive electrode current collecting tab 11 is increased to some extent due to the presence of the insulating resin layer 20, it is possible to suppress the positive electrode current collecting tab 11 from being cut when an external force is applied.

  On the other hand, as shown in FIG. 9, even when the melted positive electrode current collecting tab 11 a is deformed in the direction of the laminate outer package 25 (not shown), the melted positive electrode current collecting tab 11 a is covered with the insulating resin layer 20. Therefore, the melted positive electrode current collecting tab 11a and the aluminum layer of the laminate outer package 25 are not electrically connected. Therefore, it is possible to suppress the occurrence of inconveniences such as moisture intruding into the inside of the battery due to aluminum corrosion and the battery performance being lowered.

  From the viewpoint of reducing heat dissipation due to the presence of the insulating resin layer 20, it is desirable to increase the thickness of the insulating resin layer 20. The volume occupied by the current collector with respect to the space increases, and the energy density of the battery decreases. Therefore, it is preferable to regulate the thickness of the insulating resin layer 20 to the above-described level.

(Production method of laminated battery)
[Preparation of positive electrode plate]
90% by mass of LiCoO ₂ as a positive electrode active material, 5% by mass of carbon black as a conductive agent, 5% by mass of polyvinylidene fluoride as a binder, N-methyl-2-pyrrolidone as a solvent ( NMP) solution was mixed to prepare a positive electrode slurry. Next, this positive electrode slurry was applied to both surfaces of an aluminum foil (thickness: 15 μm) as a positive electrode current collector. Then, after drying the solvent and compressing to a thickness of 0.1 mm with a roller, the positive electrode plate 1 was produced by cutting so as to have the above-described width L1 and height L2 and the positive electrode current collecting tab 11 protruding. Thereafter, an insulating resin is applied to both surfaces of the positive electrode current collector tab 11 so as to cover a part of the positive electrode current collector tab 11, and then heated, whereby the insulating resin layer 20 is applied to each positive electrode current collector tab 11. Formed.

[Production of bag-shaped separator with positive electrode plate arranged inside]
After preparing two PP separators 3a and arranging the positive electrode plate 1 between the separators 3a, the periphery of the separator 3a was thermally welded to produce a bag-like separator 3 in which the positive electrode plate 1 was arranged. .

(Production of negative electrode plate)
A slurry was prepared by mixing 95% by mass of natural graphite powder as a negative electrode active material, 5% by mass of polyvinylidene fluoride as a binder, and an NMP solution as a solvent. It apply | coated on both surfaces of the copper foil (thickness: 10 micrometers) as a body. Then, after drying the solvent and compressing to a thickness of 0.08 mm with a roller, the negative electrode plate 2 was produced by cutting so as to have the above-described width L7 and height L8 and the negative electrode current collecting tab 12 protruding.

[Production of battery]
The negative electrode plate 2 (51 sheets) obtained as described above and the bag-like separator 3 (50 sheets) in which the positive electrode plate 1 was disposed were alternately laminated to produce a laminated electrode body. Note that the negative electrode plate 2 was disposed at the end of the laminated electrode body 10 in the laminating direction. Next, the slip prevention tape 5 was adhered to the four sides of the multilayer electrode body 10 so as to straddle the multilayer electrode body 10.

Next, the 50 positive electrode current collecting tabs 11 and the positive electrode current collecting terminals 15 protruding from the laminated electrode body 10 are welded by an ultrasonic welding method, and 51 negative electrode current collecting tabs 12 protruding from the laminated electrode body 10 are used. And the negative electrode current collector terminal 16 were welded by an ultrasonic welding method, and then the laminated electrode body 10 was disposed in the storage space of the laminate outer package 25. Thereafter, in a state in which the positive electrode current collecting terminal 15 and the negative electrode current collecting terminal 16 protrude from the laminate film 28, the laminate films 28 on the sides where both the current collector terminals 15, 16 are welded together, and then the remaining laminate film 28 is left. The laminated electrode body 10 was disposed in the laminate outer package 25 by welding two of the three sides. Finally, in a state where the internal pressure of the laminate exterior body 25 is regulated to be 30 torr or less, a non-aqueous electrolyte is injected from the opening of the laminate exterior body 25, and then the opening of the laminate exterior body 25 (the laminate film A stacked battery was prepared by welding the remaining one side). As the non-aqueous electrolyte, a mixed solvent in which ethylene carbonate (EC) and methyl ethyl carbonate (MEC) are mixed at a volume ratio of 30:70, LiPF ₆ is 1 M (mol / liter). What was melt | dissolved in the ratio was used.

(Other matters)
(1) Although the insulating layer is formed on the positive electrode current collecting tab 11 in the above embodiment, it may be formed on the negative electrode current collecting tab 12. Although it may be formed on both current collecting tabs 11 and 12, it is desirable to form the current collecting tabs on one of the current collecting tabs because the man-hour increases and the manufacturing cost increases. Moreover, even if it does not form in both the current collection tabs 11 and 12, if it forms in one current collection tab, the effect of this invention will fully be exhibited.

(2) In the above embodiment, the insulating resin layer 20 is formed only on a part of the positive electrode current collecting tab 11, but as shown in FIG. 11, it is located on the outermost side (closest to the laminate outer package 25). The insulating resin layer 20 a may be formed on the positive electrode current collecting tab 11 a (located at a position) from the joint with the positive electrode current collecting terminal 15 to the positive electrode plate 1. In addition, not only the positive electrode current collection tab 11a located in the outermost side but all the positive electrode current collection tabs 11 are good also as a structure.

(3) Although the insulating resin layer 20 is formed on each positive electrode current collecting tab 11 in the above embodiment, as shown in FIG. 12, the insulating property that integrally covers the positive electrode current collecting tab 11 in an overlapping state is provided. The resin layer 20 may be formed.

(4) In the above embodiment, the positive electrode current collecting terminal 15 is made of an aluminum plate and the negative electrode current collecting terminal 16 is made of a copper plate, but these may be made of a nickel plate. If the same material is used for both current collecting terminals 15 and 16 as described above, the production cost of the battery can be reduced.

(5) In the above-described embodiment, the storage concave portion constituting the storage space is provided in both of the two laminate films 28. However, the present invention is not limited to such a structure, and the storage concave portion is provided only in one laminate film. The other laminate film may have a structure in which no storage recess is provided. Moreover, it is not always necessary to use two laminated films, and a laminated outer package may be formed by folding one laminated film.

(6) The positive electrode active material is not limited to the above LiCoO ₂ , but may be LiNiO ₂ , LiMnO _4, or a composite thereof, and the negative electrode active material is not limited to the above natural graphite. Artificial graphite or the like may be used.

(7) In the above embodiment, the negative electrode active material layers 2a are formed on both surfaces of the negative electrode conductive core for all the negative electrode plates 2, but the negative electrode active material layers (specifically, not facing the positive electrode plate) May not have a negative electrode active material layer) present on the outer side of the outermost negative electrode plate. And if it is such a structure, since the thickness of the laminated electrode body 10 becomes small, the high capacity density of a battery can be achieved.

  The present invention can be applied to, for example, a battery used for a robot, an electric vehicle, a backup power source, and the like.

It is a disassembled perspective view of the laminated electrode body used for the laminated battery of this invention. It is a perspective view of the laminated battery of the present invention. It is a figure which shows a part of laminated battery of this invention, Comprising: The figure (a) is a top view of a positive electrode, The figure (b) is a perspective view of a separator, The figure (c) is a positive electrode arrange | positioned inside. It is a top view which shows the bag-shaped separator. It is a top view of the negative electrode used for the laminated battery of this invention. It is a perspective view of the laminated electrode body used for the laminated battery of this invention. It is explanatory drawing of the laminated electrode body used for the laminated battery of this invention. It is a side view of the laminated electrode body used for the laminated battery of this invention. It is explanatory drawing which shows a state when a positive electrode current collection tab cut | disconnects. It is explanatory drawing which shows the other state when a positive electrode current collection tab cut | disconnects. It is a top view which shows a state when a positive electrode current collection tab cut | disconnects. It is explanatory drawing which shows the modification of the laminated battery of this invention. It is explanatory drawing which shows the other modification of the laminated battery of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1: Positive electrode plate 2: Negative electrode plate 3: Separator 10: Laminated electrode body 11: Positive electrode current collection tab 12: Negative electrode current collection tab 15: Positive electrode current collection terminal 16: Negative electrode current collection terminal 20: Insulating resin layer 25: Laminate exterior body

Claims (7)

A plurality of positive electrode plates each extending from a positive electrode current collecting tab and a plurality of negative electrode plates each extending from a negative electrode current collecting tab each have a laminated electrode body that is alternately laminated via a separator. A laminated electrode body is disposed in a housing space of the exterior body, and the positive current collecting tab is joined to the positive current collecting terminal in a superimposed state, and the negative current collecting tab is joined to the negative current collecting terminal in a superimposed state, In the stacked battery in which both the current collecting terminals protrude from the exterior body,
A stacked battery, wherein an insulating layer covering at least a part of the current collecting tab is formed on at least one of the current collecting tabs.   As said exterior body, the laminate exterior body formed by joining the periphery of two laminate films provided with the metal layer and the resin layer, or one laminate film provided with the metal layer and the resin layer The laminate type battery according to claim 1, wherein a laminate outer body formed by folding back and bonding peripheral edges is used.   The stacked battery according to claim 1, wherein the insulating layer is made of an insulating resin.   The stacked battery according to claim 3, wherein a polytetrafluoroethylene resin is used as the insulating resin.   The stacked battery according to any one of claims 1 to 4, wherein the insulating layer integrally covers the current collecting tabs in the overlapping state.   Among the current collecting tabs on which the insulating layer is formed, the resin layer is formed on the current collecting tab that is closest to the laminate outer package from the junction with the current collecting terminal to the electrode plate. The stacked battery according to any one of claims 2 to 4.   The stacked type according to any one of claims 1 to 6, wherein the positive electrode active material used for the positive electrode plate and the negative electrode active material used for the negative electrode plate are made of a material capable of occluding and releasing lithium. battery.

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