Battery and module

Abstract

The invention discloses a battery and a module. A battery according to the present disclosure is provided with a laminated electrode body, a laminated exterior body, a positive electrode tab, a negative electrode tab, and an electrically insulating layer. The electrode body is formed by alternately laminating a positive electrode sheet including a positive electrode current collector and a negative electrode sheet including a negative electrode current collector in a lamination direction with a separator sheet therebetween. The positive electrode tab protrudes from the laminated exterior body toward one side in a first direction orthogonal to the lamination direction. The negative electrode tab protrudes from the laminated exterior body toward one side or the other side in the first direction. The positive electrode current collector has a positive electrode lead portion, and the positive electrode lead portion is a constituent element of the positive electrode tab. The electrical insulating layer is disposed on the surface of the positive electrode lead portion. The electrically insulating layer contains a binder and an electrically insulating filler.

Description

Technical Field

[0001] The present disclosure relates to batteries and modules. Background Art

[0002] Japanese Patent Publication No. 2015-60626 discloses a lithium-ion secondary battery (hereinafter referred to as a "battery"). The battery has: an electrode body formed by stacking a positive electrode and a negative electrode with a separator, and a non-aqueous electrolyte. The positive electrode has a main body and a narrow width portion (hereinafter referred to as a "positive electrode lead portion"), the narrow width portion protruding from the main body when viewed from above, and its width is narrower than the main body, and serves as a collector tab. In the main body of the positive electrode, a positive electrode mixture layer is formed on one or both sides of the collector. The positive electrode mixture layer contains a positive electrode active material. In at least a portion of the positive electrode lead portion of the positive electrode, a positive electrode mixture layer is not formed on the collector. The negative electrode has a main body and a narrow width portion (hereinafter referred to as a "negative electrode lead portion"), the narrow width portion protruding from the main body when viewed from above, and its width is narrower than the main body, and serves as a collector tab. In the main body of the negative electrode, a negative electrode mixture layer is formed on one or both sides of the collector. The negative electrode mixture layer contains a negative electrode active material. In at least a portion of the negative electrode lead portion of the negative electrode, a negative electrode mixture layer is not formed on the current collector. In the positive electrode lead portion of the positive electrode, at least in a portion facing the negative electrode mixture layer of the negative electrode through the separator, an anti-short circuit layer is formed on the current collector. As the anti-short circuit layer, a resin having a cross-linked structure in at least a portion is disclosed. The anti-short circuit layer is obtained by irradiating an oligomer that can be polymerized by irradiation with energy rays.

[0003] When the battery is charged and discharged alternately, the positive lead portion is prone to heat. Therefore, the anti-short circuit layer disclosed in Japanese Patent Gazette No. 2015-60626 is easily exposed to a high temperature environment. As a result, due to creep, the film thickness of the anti-short circuit layer tends to become thinner over time. The so-called "creep" refers to the phenomenon that a material deforms over time under a certain stress or load. As a result, the anti-short circuit layer may become unable to prevent a short circuit between the positive and negative electrodes. In other words, a short circuit between the positive and negative electrodes may occur. Summary of the invention

[0004] The present disclosure is completed in view of the above-mentioned actual situation.

[0005] An object of one embodiment of the present disclosure is to provide a battery and a module in which occurrence of a short circuit is suppressed.

[0006] A battery according to a first aspect of the present disclosure includes:

[0007] A stacked electrode body, in which positive electrode sheets including a positive electrode current collector and negative electrode sheets including a negative electrode current collector are alternately stacked in a stacking direction with a separator sheet interposed therebetween;

[0008] a laminated outer package housing the electrode body;

[0009] A positive electrode tab protrudes from the laminated outer casing toward one side in a first direction orthogonal to the stacking direction and is electrically connected to the plurality of positive electrode sheets;

[0010] a negative electrode tab that protrudes from the laminated outer casing toward one side or the other side in the first direction and is electrically connected to the plurality of negative electrode sheets; and

[0011] Electrical insulation layer,

[0012] The positive electrode current collector has a positive electrode lead part, and the positive electrode lead part is a component of the positive electrode tab.

[0013] The electrical insulating layer is disposed on the surface of the positive electrode lead portion.

[0014] The electrically insulating layer comprises a binder and an electrically insulating filler.

[0015] The term “laminated electrode body” means that in the battery, the positive electrode sheet, the negative electrode sheet, and the separator sheet each have a single sheet shape, and the positive electrode sheets and the negative electrode sheets are alternately laminated with the separator sheets interposed therebetween.

[0016] The term "laminated exterior body" refers to a housing made of a laminate sheet. The term "laminated sheet" refers to a sheet having a metal layer, a first resin layer laminated on one main surface of the metal layer, and a second resin layer laminated on the other main surface of the metal layer.

[0017] The so-called "electrically insulating layer" means a layer having 10 10 A layer having a resistivity of Ω·m or more.

[0018] The “positive electrode lead portion that is a component of the positive electrode tab” includes a positive electrode lead portion that is a positive electrode tab and a positive electrode lead portion that is a member separate from the positive electrode tab.

[0019] In the first embodiment, the electrical insulating layer includes a binder and an electrical insulating filler. Thus, even if the electrical insulating layer is exposed to high temperature and the thickness of the electrical insulating layer becomes thinner over time, the thickness of the electrical insulating layer is unlikely to be smaller than the average particle size of the electrical insulating filler. In other words, the function of the electrical insulating layer to impart electrical insulation to the positive lead portion is unlikely to be degraded by heat. As a result, in the battery of the first embodiment, the occurrence of a short circuit is suppressed.

[0020] A battery according to a second aspect of the present disclosure is a battery according to the first aspect, wherein the binder contains polyvinylidene fluoride.

[0021] In general, even if the battery is charged and discharged alternately, polyvinylidene fluoride is difficult to react differently from the battery reaction. As a result, the capacity of the battery of the second embodiment is difficult to decrease compared to the configuration in which the binder does not contain polyvinylidene fluoride. Moreover, the thermal stability of the electrical insulating layer of the battery of the second embodiment is excellent compared to the configuration in which the binder does not contain polyvinylidene fluoride.

[0022] A battery according to a third aspect of the present disclosure is a battery according to the first or second aspect, wherein the electrically insulating filler includes at least one of alumina beads and zirconia beads.

[0023] Thus, in the battery of the third embodiment, the occurrence of short circuit is suppressed compared to a configuration in which the electrically insulating filler does not include alumina beads or zirconia beads.

[0024] A battery according to a fourth aspect of the present disclosure is a battery according to any one of the above aspects, wherein the average particle size of the electrically insulating filler is 1 μm to 5 μm.

[0025] This makes it difficult for the thickness of the electrical insulating layer to increase, and the thickness of the electrical insulating layer is difficult to decrease to less than 1 μm due to creep. As a result, in the battery of the fourth aspect, even if the thickness of the electrical insulating layer is relatively thin, the occurrence of a short circuit can be more reliably suppressed.

[0026] A module according to a fifth aspect of the present disclosure includes:

[0027] A plurality of batteries of any one of the above forms; and

[0028] A housing for accommodating a plurality of the batteries.

[0029] According to the present disclosure, it is possible to provide a battery and a module in which occurrence of a short circuit is suppressed. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 is a perspective view of a module according to an embodiment of the present disclosure.

[0031] Figure 2 It is a top view of a state where a housing cover of a module according to an embodiment of the present disclosure is removed.

[0032] Figure 3 It is a front view of the battery according to the embodiment of the present disclosure.

[0033] Figure 4 yes Figure 3 Cross-sectional view along line IV-IV. DETAILED DESCRIPTION

[0034] Hereinafter, embodiments of the present disclosure will be described. These descriptions and examples are intended to illustrate the embodiments and do not limit the scope of the embodiments.

[0035] In the present disclosure, a combination of two or more preferred aspects is a more preferred aspect.

[0036] In the present disclosure, a numerical range expressed using "to" means a range including the numerical values ​​described before and after "to" as the lower limit and the upper limit.

[0037] In the numerical ranges recorded in stages in the present disclosure, the upper limit or lower limit recorded in one numerical range can be replaced by the upper limit or lower limit of other numerical ranges recorded in stages. In the numerical ranges recorded in the present disclosure, the upper limit or lower limit of the numerical range can be replaced by the value shown in the embodiment.

[0038] Hereinafter, embodiments of the battery and module disclosed herein will be described with reference to the accompanying drawings. In the drawings, the same or corresponding parts are denoted by the same reference numerals, and description thereof will not be repeated.

[0039] (1) Module

[0040] Module 1 of the embodiment of the present disclosure, such as Figure 1 and Figure 2 As shown, the module 1 includes a plurality of batteries 2 and a housing 10. The housing 10 accommodates the plurality of batteries 2. The module 1 is a rectangular parallelepiped.

[0041] In this embodiment, the thickness direction of the module 1 is set as the X-axis direction, the length direction of the main surface of the module 1 is set as the Y-axis direction, and the width direction of the module 1 is set as the Z-axis direction. The X-axis, the Y-axis, and the Z-axis are orthogonal to each other. The X-axis direction is an example of the second direction. The positive direction of the X-axis is an example of the upward direction. The Y-axis direction is an example of the first direction. The Z-axis direction is an example of the stacking direction. Furthermore, these directions do not limit the directions of the battery and the module disclosed in the present invention when they are used.

[0042] The length L10 of the module 1 in the Y-axis direction is, for example, 350 mm to 600 mm. The length L11 of the module 1 in the Z-axis direction is, for example, 150 mm to 250 mm. The length L12 of the module 1 in the X-axis direction is, for example, 80 mm to 110 mm.

[0043] A pair of voltage terminals 11 and a connector 12 are provided at both ends of the module 1 in the Y-axis direction. A flexible printed circuit board 13 described later is connected to the connector 12. Busbars (not shown) are welded to both ends of the module 1 in the Y-axis direction.

[0044] The housing 10 includes a housing body 101 and a housing cover 102. The housing 10 is made of an aluminum alloy. The housing 10 is formed by, for example, joining aluminum die castings at both ends of an aluminum alloy extrusion material by laser welding or the like.

[0045] like Figure 2 As shown, a plurality of batteries 2 are housed in the module 1 in an arranged state. In this embodiment, 24 batteries 2 are arranged along the Z-axis direction. Adjacent batteries 2 are bonded to each other. For details of the batteries 2, refer to Figure 3 and Figure 4 This will be described later.

[0046] A flexible printed circuit (FPC) 13 is disposed on the battery 2. The flexible printed circuit 13 is formed in a strip shape with the X-axis direction as the longitudinal direction, and thermistors 14 are provided at both ends of the flexible printed circuit 13. In the module 1, the thermistor 14 is not bonded to the battery 2, but is pressed toward the battery 2 by the case cover 102.

[0047] One or more buffers (not shown) are accommodated inside the module 1. For example, the buffer is a thin plate-shaped member that can be elastically deformed, and is arranged between adjacent batteries 2 with the arrangement direction of the batteries 2 as the thickness direction. In this embodiment, as an example, buffers are arranged at both ends and the center of the module 1 in the longitudinal direction.

[0048] (2)Battery

[0049] Battery 2, such as Figure 3 As shown, the battery 2 includes an electrode body 21, a laminated outer package 22, a positive electrode tab 23, a negative electrode tab 24, a non-aqueous electrolyte (not shown), and a plurality of electrical insulating layers 25. The battery 2 is a rectangular parallelepiped.

[0050] The laminated outer package 22 contains the electrode body 21, the nonaqueous electrolyte, and a plurality of electrical insulating layers 25. The positive electrode tab 23 protrudes from the laminated outer package 22 in the positive direction of the Y axis. The negative electrode tab 24 protrudes from the laminated outer package 22 in the negative direction of the Y axis.

[0051] The length L1 of the battery 2 in the Y-axis direction (see Figure 3 ) is, for example, 530 mm to 600 mm. The length L2 of the battery 2 in the X-axis direction (see Figure 3 ) is, for example, 80 mm to 110 mm. The length L3 of the battery 2 in the Z-axis direction (see Figure 4 ) For example, 7.0mm to 9.0mm.

[0052] (2.1) Electrode body

[0053] The structure of the electrode body 21 is a stacked type. Figure 4 As shown, the electrode body 21 includes a plurality of positive electrode sheets 211, a plurality of negative electrode sheets 212, and a plurality of separator sheets 213. The electrode body 21 is formed by alternately stacking the positive electrode sheets 211 and the negative electrode sheets 212 with the separator sheets 213 interposed therebetween along the Z-axis direction.

[0054] The number of each of the positive electrode sheet 211 , the negative electrode sheet 212 , and the separator sheet 213 is not particularly limited, and can be appropriately selected according to the purpose of the battery 2 .

[0055] (2.1.1) Positive electrode

[0056] The positive electrode sheet 211 has a positive electrode current collector 2111 (for example, aluminum foil, etc.) and a positive electrode active material layer 2112 supported on both sides of the positive electrode current collector 2111. The positive electrode active material layer 2112 contains a positive electrode active material. The positive electrode active material releases lithium ions into the non-aqueous electrolyte or absorbs lithium ions from the non-aqueous electrolyte. The positive electrode active material can be any known positive electrode active material (for example, LiNiO2, LiNi 1 / 3 Co 1 / 3 Mn 1 / 3 The positive electrode active material layer 2112 may further contain a known conductive material (for example, carbon black), trilithium phosphate, and a known binder (for example, polyvinylidene fluoride).

[0057] (2.1.2) Negative electrode

[0058] The negative electrode sheet 212 has a negative electrode collector 2121 (for example, copper foil, etc.) and a negative electrode active material layer 2122 supported on both sides of the negative electrode collector 2121. The negative electrode active material layer 2122 contains a negative electrode active material. The negative electrode active material absorbs lithium ions as charge carriers from the non-aqueous electrolyte and releases lithium ions into the non-aqueous electrolyte during charging and discharging. The negative electrode active material can be any known negative electrode active material (artificial graphite, lithium alloy (for example, LiXM, M is C, Si, Sn, Sb, Al, Mg, Ti, Bi, Ge, Pb or P, etc., and X is a natural number)). The negative electrode active material layer 2122 may further contain a known binder (for example, styrene butadiene copolymer, etc.).

[0059] (2.1.3) Diaphragm

[0060] The diaphragm sheet 213 electrically insulates the positive electrode sheet 211 from the negative electrode sheet 212, and provides a path for lithium ions to move between the positive electrode active material layer 2112 and the negative electrode active material layer 2122. As the diaphragm sheet 213, a porous film or the like can be cited. As the material of the porous film, for example, polyethylene, polypropylene, etc. can be cited. The diaphragm sheet 213 can be a single-layer structure or a multi-layer structure.

[0061] (2.2) Laminated outer body

[0062] The laminated outer casing 22 covers the electrode body 21 and seals the electrode body 21 and the non-aqueous electrolyte together with the positive electrode tab 23 and the negative electrode tab 24. In this embodiment, the laminated outer casing 22 has a single-cup structure (see Figure 4 ). The so-called "single cup structure laminated outer body" means a laminated outer body having a bending line, a cup portion (recessed portion) and a flat portion that can accommodate the entire electrode body, and a laminated outer body that is bent along the bending line so that the flat portion covers the recessed portion. The laminated outer body 22 has a laminated sheet 221 and a plurality of tab films 222. The plurality of tab films 222 are respectively welded to the positive electrode tab 23 or the negative electrode tab 24, and the laminated sheet 221.

[0063] The laminate 221 has a metal layer, an inner resin layer and an outer resin layer. The inner resin layer is laminated on the surface of the metal layer on the electrode body 21 side. The outer resin layer is laminated on the surface of the metal layer on the side opposite to the electrode body 21 side. The metal layer blocks the entry and exit of gases (e.g., moisture, air, etc.) outside the battery 2 and inside the battery 2. The material of the metal layer is metal (e.g., aluminum, etc.). The inner resin layer electrically insulates the electrode body 21, the positive electrode tab 23 and the negative electrode tab 24 from the metal layer. The inner resin layer may contain a thermoplastic resin. The outer resin layer improves the durability of the laminate 221. The outer resin layer may contain a thermoplastic resin. As the respective thermoplastic resins of the inner resin layer and the outer resin layer, for example, olefin resins (e.g., polypropylene, polyethylene, etc.), polyvinyl chloride, polyvinylidene chloride, etc. can be listed.

[0064] The tab film 222 has the function of electrically insulating the laminate sheet 221 from the positive electrode tab 23 and the negative electrode tab 24, and the function of bonding the laminate sheet 221 to the positive electrode tab 23 and the negative electrode tab 24. The tab film 222 contains a thermoplastic resin. As the thermoplastic resin of the tab film 222, the same thermoplastic resin as the thermoplastic resin exemplified as the respective thermoplastic resins of the inner resin layer and the outer resin layer can be cited.

[0065] (2.3) Electrical insulation layer

[0066] The positive electrode current collector 2111 has a positive electrode lead part R2111, which is a component of the positive electrode tab 23. The negative electrode current collector 2121 has a negative electrode lead part R2121, which is a component of the negative electrode tab 24. In this embodiment, a plurality of electrical insulating layers 25 are arranged on both sides of the positive electrode lead part R2111 and both sides of the negative electrode lead part R2121.

[0067] The thickness of the electrical insulating layer is not particularly limited, and may be about twice the thickness of at least one of the alumina beads and the zirconia beads (hereinafter also referred to as "beads"), and may be 2 μm to 10 μm. In the present embodiment, the electrical insulating layer includes polyvinylidene fluoride (hereinafter also referred to as "PVDF") and beads, and may be composed of PVDF and beads. The volume ratio of PVDF to beads (volume of PVDF: volume of beads) may be 50:50 to 80:20, and may be 60:40. PVDF is an example of a binder. Beads are an example of an electrically insulating filler.

[0068] The electrical insulating layer may further include polyethylene (PE), polypropylene (PP), styrene butadiene rubber (SBR) and the like in addition to PVDF, and may further include metal oxide beads (but excluding beads), metal nitride beads and the like in addition to beads. Examples of the metal oxide beads (but excluding beads) include silicon dioxide and the like. Examples of the metal nitride beads include silicon nitride and the like.

[0069] In the present embodiment, the average particle size of the beads is 1 μm to 5 μm. The so-called "average particle size" refers to the particle size corresponding to the cumulative 50 volume % from the microparticle side in the volume-based particle size distribution measured by a particle size distribution measuring device based on a laser diffraction scattering method (particle size distribution D50, median diameter).

[0070] (2.4) Positive electrode tab

[0071] The positive electrode tab 23 is electrically connected to a plurality of positive electrode current collectors 2111. The positive electrode tab 23 includes a metal sheet 231 and a positive electrode lead portion R2111 of the positive electrode current collector 2111. The metal sheet 231 is electrically connected to the positive electrode lead portion R2111. As the material of the metal sheet 231, metal (for example, stainless steel (SUS)) and the like can be cited. The length L4 of the positive electrode tab 23 in the X-axis direction is, for example, 40 mm to 50 mm.

[0072] (2.5) Negative electrode tab

[0073] The negative electrode tab 24 is electrically connected to a plurality of negative electrode current collectors 2121. The negative electrode tab 24 includes a metal sheet 241 and a negative electrode lead portion R2121 of the negative electrode current collector 2121. The metal sheet 241 is electrically connected to the negative electrode lead portion R2121. As the material of the metal sheet 241, metal (for example, stainless steel (SUS)) and the like can be cited. The length L4 of the negative electrode tab 24 in the X-axis direction is, for example, 40 mm to 50 mm.

[0074] (2.6) Non-aqueous electrolyte

[0075] The battery 2 has a non-aqueous electrolyte. The non-aqueous electrolyte is contained in the laminated outer package 22 together with the electrode body 21. The non-aqueous electrolyte can be any electrolyte in which a supporting electrolyte (e.g., LiPF6, etc.) as an electrolyte is dissolved or dispersed in a non-aqueous solvent (e.g., ethyl methyl carbonate, etc.). The non-aqueous electrolyte may also contain various additives (e.g., lithium bis(oxalatoborate, etc.).

[0076] (3) Effect

[0077] As reference Figure 1 to Figure 4 As described above, the battery 2 includes an electrode body 21, a laminated outer body 22, a positive electrode tab 23, a negative electrode tab 24, and an electrical insulating layer 25. The positive electrode current collector 2111 includes a positive electrode lead portion R2111, which is a component of the positive electrode tab 23. The electrical insulating layer 25 is arranged on the surface of the positive electrode lead portion R2111. The electrical insulating layer 25 contains a binder and an electrical insulating filler.

[0078] Thus, even if the electrical insulating layer 25 is exposed to high temperature and the thickness of the electrical insulating layer 25 decreases over time, the thickness of the electrical insulating layer 25 is unlikely to become smaller than the average particle size of the electrical insulating filler. In other words, the function of the electrical insulating layer 25 to impart electrical insulation to the positive lead portion R2111 is unlikely to be degraded by heat. As a result, the occurrence of a short circuit in the battery 2 is suppressed.

[0079] As reference Figure 1 to Figure 4 As described, in the battery 2 , the binder contains polyvinylidene fluoride.

[0080] Thus, the capacity of the battery 2 is less likely to decrease compared to a configuration in which the binder does not contain PVDF. In addition, the electrical insulating layer 25 of the battery 2 has excellent thermal stability compared to a configuration in which the binder does not contain polyvinylidene fluoride.

[0081] As reference Figure 1 to Figure 4 As described above, in battery 2 , the electrically insulating filler includes at least one of alumina beads and zirconia beads.

[0082] Thus, in the battery 2 , the occurrence of a short circuit is suppressed compared to a configuration in which the electrically insulating filler does not include alumina beads or zirconia beads.

[0083] As reference Figure 1 to Figure 4 As described above, in the battery 2 , the average particle size of the electrically insulating filler is 1 μm to 5 μm.

[0084] This makes it difficult for the thickness of the electrical insulating layer 25 to increase, and makes it difficult for the thickness of the electrical insulating layer 25 to decrease to less than 1 μm due to creep. As a result, in the battery 2, even if the thickness of the electrical insulating layer 25 is relatively thin, the occurrence of a short circuit can be more reliably suppressed.

[0085] As reference Figure 1 to Figure 4 As described above, the module 1 includes the plurality of batteries 2 and the case 10 .

[0086] (4) Modification

[0087] In this embodiment, the binder includes PVDF, but the present invention is not limited thereto. The binder may not include PVDF. When the binder does not include PVDF, examples of the binder include polyethylene, polypropylene, styrene butadiene rubber, and the like.

[0088] In this embodiment, the electrically insulating filler includes beads, but the present invention is not limited thereto, and the electrically insulating filler may not include beads. When the electrically insulating filler does not include beads, examples of the electrically insulating filler include silicon dioxide, silicon nitride, and the like.

[0089] In the present embodiment, the average particle size of the electrically insulating filler is 1 μm to 5 μm, but the present invention is not limited thereto. The average particle size of the electrically insulating filler may be greater than 5 μm or less than 1 μm.

[0090] In this embodiment, the positive electrode tab 23 includes the metal sheet 231 and the positive electrode lead portion R2111 of the positive electrode current collector 2111 , but the present invention is not limited thereto. The positive electrode tab 23 may be composed of the positive electrode lead portion R2111 of the positive electrode current collector 2111 .

[0091] In this embodiment, the laminated outer casing 22 has a single cup structure (see Figure 4 ), but the present invention is not limited to this. In the present disclosure, the laminated outer casing 22 may also be a double-cup structure. The so-called "laminated outer casing with a double-cup structure" means: a laminated outer casing having a bending line, a first cup portion (recess) capable of accommodating a portion of the electrode body, and a second cup portion (recess) capable of accommodating a portion of the electrode body, and capable of accommodating the entire electrode body in a space formed by the overlap of the first cup portion and the second cup by bending along the bending line.

[0092] In this embodiment, the positive electrode tab 23 protrudes from the laminated outer casing 22 toward the positive direction of the Y axis, and the negative electrode tab 24 protrudes from the laminated outer casing 22 toward the negative direction of the Y axis, but the present invention is not limited to this. In the present disclosure, the positive electrode tab 23 and the negative electrode tab 24 may also protrude from the laminated outer casing 22 toward the positive direction of the Y axis or the negative direction of the Y axis.

[0093] In this embodiment, the number of batteries 2 housed in the module 1 is 24, but the present invention is not limited thereto. The number of batteries 2 housed in the module 1 may be 23 or less, or 25 or more.

[0094] In this embodiment, the battery 2 is used as a vehicle power supply, but the present disclosure is not limited thereto. In the present disclosure, the battery 2 may be used as a power supply for an information processing device (eg, a personal computer, a smartphone, etc.), a power supply for power storage, etc.

Claims

1. A battery having: A stacked electrode body, in which positive electrode sheets including a positive electrode current collector and negative electrode sheets including a negative electrode current collector are alternately stacked in a stacking direction with a separator sheet interposed therebetween; a laminated outer package housing the electrode body; A positive electrode tab protrudes from the laminated outer casing toward one side in a first direction orthogonal to the stacking direction and is electrically connected to the plurality of positive electrode sheets; a negative electrode tab that protrudes from the laminated outer casing toward one side or the other side in the first direction and is electrically connected to the plurality of negative electrode sheets; and Electrical insulation layer, The positive electrode current collector has a positive electrode lead portion, and the positive electrode lead portion is a component of the positive electrode tab. The electrical insulating layer is disposed on the surface of the positive electrode lead portion. The electrically insulating layer comprises a binder and an electrically insulating filler.

2. The battery according to claim 1, The binder includes polyvinylidene fluoride.

3. The battery according to claim 1 or 2, The electrically insulating filler includes at least one of alumina beads and zirconia beads.

4. The battery according to claim 1 or 2, The average particle size of the electrically insulating filler is 1 μm to 5 μm.

5. A module comprising: A plurality of batteries according to claim 1 or 2; and A housing for accommodating a plurality of the batteries.

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