Laminated battery and method for manufacturing laminated battery

Abstract

A laminated battery (1) includes a stacked cell (2), a sealant (3), and a laminate film (4) that houses the stacked cell (2). The stacked cell (2) includes a cell (20), a current collector (21) stacked on the cell (20), and a tab lead (22). The tab lead (22) includes a tab connection section (221) that is connected to the current collector (21), and a lead section (222) that is continuous with the tab connection section (221) and that protrudes from a peripheral end of the laminate film (4). The laminate film (4) includes a metal layer (41). At the peripheral end of the laminate film (4), the sealant (3) is disposed between an inner peripheral surface of the laminate film (4) and an outer peripheral surface of the lead section (222), a free end (411) of the metal layer (41) includes a burr (412) bent in the thickness direction, and the burr (412) is oriented toward the side opposite to the lead section (222).

Description

Laminated battery and manufacturing method of laminated battery

[0001] The present disclosure relates to a laminate battery and a method for manufacturing a laminate battery.

[0002] Conventionally, there has been known a battery in which a battery element having a positive electrode layer, a negative electrode layer, a positive electrode terminal connected to the positive electrode layer, and a negative electrode terminal connected to the negative electrode layer is wrapped in an exterior film so that the positive electrode terminal and the negative electrode terminal protrude (see, for example, Patent Document 1).

[0003] In the battery described in Patent Document 1, the exterior film has a first insulating layer, a second insulating layer facing the first insulating layer, and a metal layer interposed between the first insulating layer and the second insulating layer. Furthermore, on the end surface on the side where the positive electrode terminal and the negative electrode terminal protrude, the metal layer is located inside the first insulating layer and the second insulating layer. Therefore, it is possible to prevent short circuits between the terminals of the battery element and the metal layer of the exterior film.

[0004] Japanese Patent Application Laid-Open No. 2022-114282

[0005] However, in the battery of Patent Document 1, in order to position the metal layer in the exterior film more inward than the first insulating layer and the second insulating layer, ultrasonic treatment is performed on the exterior film before cutting. In other words, the manufacturing process of the battery of Patent Document 1 needs to include an ultrasonic treatment step, and an apparatus for performing the ultrasonic treatment is also required. Therefore, the battery of Patent Document 1 has problems such as a complicated manufacturing process, an increased manufacturing space, and a need for capital investment.

[0006] The present disclosure provides a laminate battery and a method for manufacturing the laminate battery that can suppress short circuits between a laminate film and a laminate battery using simple equipment and processes.

[0007] The present disclosure [1] provides a laminated battery comprising a laminated battery, a sealant, and a laminate film that houses the laminated battery, wherein the laminated battery comprises a cell having a positive electrode layer, a negative electrode layer, and a solid electrolyte layer disposed between the positive electrode layer and the negative electrode layer, a current collector laminated on the cell, and a tab lead connected to the current collector, the tab lead comprising a tab connection portion connected to the current collector and a lead portion that is continuous with the tab connection portion and protrudes from a peripheral edge of the laminate film, the laminate film comprising a metal layer, and at the peripheral edge of the laminate film, the sealant is disposed between an inner peripheral surface of the laminate film and an outer peripheral surface of the lead portion, and the free end of the metal layer comprises a burr that is bent in the thickness direction, the burr facing away from the lead portion.

[0008] In this laminated battery, the sealant is disposed between the inner peripheral surface of the laminated film and the outer peripheral surface of the lead portion at the peripheral edge of the laminated film, and the burrs at the free end of the metal layer of the laminated film face away from the lead portion, which prevents the burrs at the free end of the metal layer from penetrating the sealant and coming into contact with the lead portion, thereby preventing a short circuit between the laminated film and the stacked battery.

[0009] The present disclosure [2] includes the laminated battery according to [1], wherein the peripheral edge of the laminated film is inclined in a direction opposite to the protruding direction of the lead portion as it approaches the tip of the burr.

[0010] In this laminated battery, the peripheral edge of the laminate film is inclined in the opposite direction to the protruding direction of the lead portion toward the tip of the burr of the metal layer. Therefore, even when the laminated film is heat-sealed and pressed, the metal layer is present between the burr and the lead portion in addition to the sealant, which further reduces the risk of short circuits between the laminated film and the stacked battery.

[0011] The present disclosure [3] includes the laminate battery according to [1], wherein the laminate film further includes a resin layer on the inner circumferential surface of the metal layer.

[0012] In this laminated battery, the laminate film further includes a resin layer on the inner peripheral surface of the metal layer, which further prevents burrs on the free end of the metal layer from coming into contact with the lead portion when the peripheral edge of the laminate film is pressed for heat sealing.

[0013] The present disclosure [4] includes the laminated battery according to [3], wherein the resin layer protrudes from the metal layer at the peripheral end of the laminate film in the direction in which the lead portion protrudes.

[0014] In this laminated battery, the resin layer at the peripheral edge of the laminate film protrudes beyond the metal layer in the direction of the protruding lead portion. Therefore, even when the laminate film is heat-sealed and pressed, the resin layer can be reliably positioned between the burrs and the lead portion, more reliably preventing short circuits between the laminate film and the stacked battery.

[0015] The present disclosure [5] includes the laminate battery according to [3] or [4], in which the total thickness of the sealant and the resin layer is greater than the length of the burr in the thickness direction of the metal layer.

[0016] In this laminated battery, the combined thickness (total thickness) of the sealant and resin layer is greater than the thickness of the burr in the metal layer. Therefore, even if the direction of the burr at the free end of the metal layer changes when the peripheral edge of the laminate film is pressed for heat sealing, the sealant and resin layer can prevent the burr at the free end of the metal layer from coming into contact with the lead portion.

[0017] The present disclosure [6] includes the laminate battery according to [5], wherein the total thickness of the sealant and the resin layer is 50 μm or more.

[0018] In this laminated battery, the combined thickness of the sealant and resin layer is 50 μm or more, so even if the metal layer of the laminate film is relatively thick, the sealant and resin layer can prevent burrs at the free end of the metal layer from coming into contact with the lead portion.

[0019] The present disclosure [7] includes the laminate battery according to [1], wherein the current collector comprises a positive electrode current collector in contact with the positive electrode layer and a negative electrode current collector in contact with the negative electrode layer; the tab lead comprises a positive electrode tab lead connected to the positive electrode current collector and a negative electrode tab lead connected to the negative electrode current collector; the positive electrode tab lead comprises a positive electrode tab connection portion connected to the positive electrode current collector and a positive electrode lead portion that is continuous with the positive electrode tab connection portion and protrudes from the peripheral edge of the laminate film; the negative electrode tab lead comprises a negative electrode tab connection portion connected to the negative electrode current collector and a negative electrode lead portion that is continuous with the negative electrode tab connection portion and protrudes from the peripheral edge of the laminate film; and the protruding direction of the positive electrode lead portion is the same as the protruding direction of the negative electrode lead portion.

[0020] In this laminated battery, the positive electrode lead portion of the positive electrode tab lead protrudes in the same direction as the negative electrode lead portion of the negative electrode tab lead, which makes it easier to connect the laminated battery to the outside.

[0021] The present disclosure [8] includes the laminate battery according to [1], wherein the current collector comprises a positive electrode current collector in contact with the positive electrode layer and a negative electrode current collector in contact with the negative electrode layer, the tab lead comprises a positive electrode tab lead connected to the positive electrode current collector and a negative electrode tab lead connected to the negative electrode current collector, the positive electrode tab lead comprises a positive electrode tab connection portion connected to the positive electrode current collector and a positive electrode lead portion that is continuous with the positive electrode tab connection portion and protrudes from the peripheral edge of the laminate film, and the negative electrode tab lead comprises a negative electrode tab connection portion connected to the negative electrode current collector and a negative electrode lead portion that is continuous with the negative electrode tab connection portion and protrudes from the peripheral edge of the laminate film, and the protruding direction of the positive electrode lead portion differs from the protruding direction of the negative electrode lead portion.

[0022] In this laminate battery, the protruding direction of the positive electrode lead portion of the positive electrode tab lead differs from the protruding direction of the negative electrode lead portion of the negative electrode tab lead, thereby reliably preventing contact between the positive electrode tab lead and the negative electrode tab lead.

[0023] The present disclosure [9] includes a method for manufacturing a laminated battery, the method comprising: cutting a laminated film having a metal layer to generate burrs bending in the thickness direction at free ends of the metal layer; preparing a laminated battery including: a cell having a positive electrode layer, a negative electrode layer, and a solid electrolyte layer disposed between the positive electrode layer and the negative electrode layer; a current collector laminated on the cell; a tab lead connected to the current collector and including a tab connection portion and a lead portion continuous with the tab connection portion; and a sealant bonded to the lead portion; arranging the laminated battery having the sealant bonded and the laminated film at a peripheral end of the laminated film so that the lead portion protrudes from the peripheral end of the laminated film, the sealant is located between an inner peripheral surface of the laminated film and an outer peripheral surface of the lead portion, and the burr faces away from the lead portion; and heat-sealing the peripheral end of the laminated film from which the lead portion protrudes.

[0024] According to this method for manufacturing a laminated battery, when a laminated film having a metal layer is cut, burrs that bend in the thickness direction are generated at the free end of the metal layer, but the method includes a step of positioning the laminated battery and the laminated film so that the burrs on the metal layer face away from the lead portion of the laminated battery. Therefore, a laminated battery that can suppress short circuits between the laminated film and the laminated battery can be manufactured using simple equipment and steps.

[0025] The present disclosure

[10] includes the method for manufacturing a laminated battery according to [9], wherein the step of preparing the laminated battery to which the sealant is bonded includes the steps of: preparing the cell having the positive electrode layer, the negative electrode layer, and a solid electrolyte layer disposed between the positive electrode layer and the negative electrode layer, and the current collector to be laminated on the cell; preparing the tab lead having the tab connection portion and the lead portion continuous with the tab connection portion, and bonding the sealant to the lead portion; and connecting the tab connection portion to the current collector in the tab lead to which the sealant is bonded.

[0026] According to this laminate battery manufacturing method, the laminate battery preparation process includes the steps of preparing cells and current collectors, preparing tab leads and joining a sealant to the lead portions of the tab leads, and connecting the tab connection portions of the tab leads with the sealant joined to the current collectors. This allows for selective use of tab leads that match the shapes of the laminate battery and laminate film, making it easy to connect the laminate battery to the outside.

[0027] The present disclosure

[11] includes the method for manufacturing a laminated battery according to [9], wherein the step of preparing the laminated battery to which the sealant is bonded includes the steps of: preparing a laminated battery including the cell having the positive electrode layer, the negative electrode layer, and a solid electrolyte layer disposed between the positive electrode layer and the negative electrode layer; and the current collector having the tab lead laminated on the cell, the tab lead including the tab connection portion and the lead portion continuous with the tab connection portion; and bonding the sealant to the lead portion.

[0028] According to this method for manufacturing a laminate battery, the current collector has a tab lead, which further simplifies the manufacturing process.

[0029] In the laminate battery of the present disclosure, the free end of the metal layer of the laminate film has a burr that bends in the thickness direction, but this burr faces away from the lead portion of the stacked battery, which prevents the burr from penetrating the sealant and coming into contact with the lead portion, thereby preventing a short circuit between the laminate film and the stacked battery.

[0030] The method for manufacturing a laminated battery according to the present disclosure includes a step of positioning the laminated battery and the laminated film so that, although burrs that bend in the thickness direction are generated at the free ends of the metal layers when the laminated film having the metal layers is cut, the burrs face away from the lead portions of the laminated battery. Therefore, the above-described laminated battery can be manufactured using simple equipment and steps.

[0031] FIG. 1 is a plan view of one embodiment of a laminated battery of the present disclosure. FIG. 2 is an A-A cross-sectional view of the laminated battery shown in FIG. 1. FIG. 3 is a cross-sectional view showing the layer structure of a cell in the laminated battery. FIG. 4 is an enlarged view of the peripheral edge of the laminated film in the laminated battery shown in FIG. 2. FIGS. 5A to 5D show one embodiment of a method for manufacturing a laminated battery. FIG. 5A shows a step of cutting the laminated film, FIG. 5B shows a step of preparing a cell and a current collector, FIG. 5C shows a step of preparing tab leads and bonding a sealant to the lead portions of the tab leads, and FIG. 5D shows a step of connecting the tab connection portion of the tab lead bonded with the sealant to the current collector to prepare a laminated battery bonded with the sealant. FIGS. 6A and 6B show subsequent steps to one embodiment of the method for manufacturing the laminated battery shown in FIG. 5D. Fig. 6A shows the process of arranging a laminate film and a laminated battery with a sealant bonded thereto, and Fig. 6B shows the process of heat-sealing the peripheral edge of the laminated film. Fig. 7 shows an A-A cross-sectional view of a first modified laminated battery and an enlarged view of the peripheral edge of the laminated film. Fig. 8 shows an A-A cross-sectional view of a second modified laminated battery and an enlarged view of the peripheral edge of the laminated film. Fig. 9 shows an A-A cross-sectional view of a third modified laminated battery and an enlarged view of the peripheral edge of the laminated film.

[0032] 1. Laminated Battery One embodiment of a laminated battery of the present disclosure will be described with reference to FIGS.

[0033] 1 and 2, the laminate battery 1 includes a stacked battery 2, a sealant 3, and a laminate film 4 that houses the stacked battery 2. The laminated battery 1 is an all-solid-state battery that uses a solid electrolyte as the electrolyte.

[0034] 1.1. Stacked Battery The stacked battery 2 includes cells 20, current collectors 21 stacked on the cells 20, and tab leads 22 connected to the current collectors 21.

[0035] [Cell] The shape of the cell 20 is not particularly limited, but examples thereof include a sheet shape, a film shape, and a plate shape.

[0036] The cell 20 has, for example, a substantially rectangular shape when viewed in the thickness direction of the cell 20. The cell 20 may have a substantially circular shape when viewed in the thickness direction of the cell 20.

[0037] The thickness of the cell 20 is, for example, 100 μm or more, or preferably 200 μm or more, and for example, 1000 μm or less, or preferably 800 μm or less.

[0038] 3 , the cell 20 has a positive electrode layer 201, a negative electrode layer 202, and a solid electrolyte layer 203. The cell 20 preferably comprises the positive electrode layer 201, the negative electrode layer 202, and the solid electrolyte layer 203. In this embodiment, the cell 20 is a bare cell independent of the current collector 21. However, the cell 20 may be integrated with the current collector 21.

[0039] The positive electrode layer 201 is disposed away from the negative electrode layer 202 in the thickness direction of the cell 20. The positive electrode layer 201 is disposed on the opposite side of the solid electrolyte layer 203 from the negative electrode layer 202 in the thickness direction of the cell 20. The positive electrode layer 201 is in contact with the solid electrolyte layer 203 but is not in contact with the negative electrode layer 202.

[0040] The positive electrode layer 201 is formed from a powder containing a positive electrode active material. The positive electrode layer 201 may also contain a powder of a solid electrolyte and a resin such as a binder. In this embodiment, the positive electrode layer 201 is formed from a mixture of a powder of a positive electrode active material and a powder of a solid electrolyte, and does not contain a resin such as a binder. The positive electrode layer 201 does not have to contain a solid electrolyte. In other words, the positive electrode layer 201 may be made of only the positive electrode active material.

[0041] The positive electrode active material may be, for example, a lithium-containing oxide. Examples of the lithium-containing oxide include lithium-nickel composite oxide (LiNiＸ M １－Ｘ O ２ ), lithium cobalt oxide (LiCoO ２ ), lithium nickel oxide (LiNiO ２ ), lithium nickel cobalt aluminum composite oxide (LiNi ０．８ Co ０．１５ Al ０．０５ O2, NCA-based layered oxide), lithium manganese oxide (spinel-type lithium manganese oxide (LiMn ２ O ４ )), Li-excess composite oxide (Li ２ MnO ３ -LiMO ２ ) are listed.

[0042] The positive electrode active material is not limited to a lithium-containing oxide as long as it is capable of inserting and extracting lithium ions. Examples of the positive electrode active material include olivine-based compounds (LiMPO ４ ) and sulfur-containing compounds (Li ２ S), where M represents a transition metal.

[0043] As the positive electrode active material, a lithium-containing oxide containing at least one selected from the group consisting of Co, Ni, and Mn is preferable, from the viewpoint of easily obtaining a high capacity.

[0044] In addition, the surface of the positive electrode active material may be coated with a coating material from the viewpoint of improving rate characteristics. ４ Ti ５ O １２ , LiTaO ３ , Li ４ NbO ３ , LiAlO ２ , Li ２ ZrO ３ , Li ２ WO ４ , Li ２ TiO ３ , Li ２ B ４ O ７ , Li ３ P.O. ４ , Li ２ MoO ４ , LiBO２ , alumina (Al ２ O ３ ), and carbon (C).

[0045] The positive electrode active materials can be used alone or in combination of two or more kinds.

[0046] The solid electrolyte exhibits lithium ion conductivity. Examples of the solid electrolyte include organic solid electrolytes and inorganic solid electrolytes.

[0047] Inorganic solid electrolytes include, for example, sulfides, oxides, nitrides, and hydrides.

[0048] Examples of sulfides include Li ２ Examples of the sulfide include those containing S and another sulfide containing at least one element selected from the group consisting of Group 13 elements, Group 14 elements, and Group 15 elements of the periodic table. Examples of Group 13 elements, Group 14 elements, and Group 15 elements of the periodic table include P, Si, Ge, As, Sb, and Al. Preferred examples include P, Si, and Ge. More preferred examples include P.

[0049] Specifically, the sulfide may be, for example, Li ２ S-SiS ２ , Li2S-P ２ S ５ , Li ２ S-GeS ２ , Li ２ S-B ２ S ３ , Li ２ S-Ga ２ S ３ , Li ２ S-Al ２ S ３ , Li ２ S-GeS ２ -P ２ S ５ , Li ２ S-Al ２ S ３ -P ２ S ５ , Li ２ S-P ２ S ３ , Li ２ S-P２ S ３ -P ２ S ５ , LiX-Li ２ S-P ２ S ５ , LiX-Li ２ S-SiS ２ , and LiX-Li ２ S-B ２ S ３ (X: I, Br or Cl).

[0050] The solid electrolyte is preferably an inorganic solid electrolyte. More preferably, a sulfide is used. The solid electrolyte may be used alone or in combination of two or more. When the positive electrode layer 201 contains a positive electrode active material and a solid electrolyte, the ratio of the positive electrode active material to the solid electrolyte is not limited.

[0051] The thickness of the positive electrode layer 201 is, for example, 50 μm or more, preferably 100 μm or more, and for example, 500 μm or less, preferably 300 μm or less.

[0052] The negative electrode layer 202 is disposed away from the positive electrode layer 201 in the thickness direction of the cell 20. The negative electrode layer 202 is disposed on the opposite side of the solid electrolyte layer 203 from the positive electrode layer 201 in the thickness direction of the cell 20. The negative electrode layer 202 is in contact with the solid electrolyte layer 203 but is not in contact with the positive electrode layer 201.

[0053] The negative electrode layer 202 is formed from a powder containing a negative electrode active material. The negative electrode layer 202 may contain a solid electrolyte and a resin such as a binder. In this embodiment, the negative electrode layer 202 is formed from a mixture of a powder of the negative electrode active material and a powder of the solid electrolyte, and does not contain a resin such as a binder. The negative electrode layer 202 does not necessarily have to contain a solid electrolyte. The negative electrode layer 202 may be made of only the negative electrode active material.

[0054] The negative electrode active material is not limited as long as it is a material capable of inserting and extracting lithium ions, and examples of the negative electrode active material include carbon materials, metals and alloys thereof, semimetals, and compounds of metals or semimetals.

[0055] Examples of carbon materials include graphite (natural graphite, artificial graphite), hard carbon, and amorphous carbon. Examples of metals and their alloys include lithium and its alloys. Examples of metalloids include silicon. Examples of metal or metalloid compounds include oxides, sulfides, nitrides, hydrates, and silicides (lithium silicides) of metals or metalloids. Examples of metal or metalloid oxides include titanium oxide and silicon oxide.

[0056] The negative electrode active material may be used alone or in combination of two or more thereof. For example, silicon oxide and a carbon material may be used in combination as the negative electrode active material.

[0057] Examples of the solid electrolyte contained in the anode layer 202 include the solid electrolytes described above for the cathode layer 201. Preferably, the solid electrolyte contained in the anode layer 202 is the same as the solid electrolyte contained in the cathode layer 201. When the anode layer 202 contains an anode active material and a solid electrolyte, the ratio of the anode active material to the solid electrolyte is not limited.

[0058] The thickness of the negative electrode layer 202 is preferably approximately the same as the thickness of the positive electrode layer 201. The thickness of the negative electrode layer 202 is, for example, 50 μm or more, preferably 100 μm or more, and for example, 500 μm or less, preferably 300 μm or less.

[0059] The solid electrolyte layer 203 is disposed between the positive electrode layer 201 and the negative electrode layer 202 in the thickness direction of the cell 20. The solid electrolyte layer 203 is formed from a powder containing a solid electrolyte. The solid electrolyte layer 203 may contain a resin such as a binder. In this embodiment, the solid electrolyte layer 203 is formed from a solid electrolyte.

[0060] Examples of the solid electrolyte include the solid electrolytes described above for the positive electrode layer 201. Preferably, the solid electrolyte contained in the solid electrolyte layer 203 is the same as the solid electrolyte contained in the positive electrode layer 201.

[0061] The thickness of the solid electrolyte layer 203 is, for example, 10 μm or more, or preferably 30 μm or more, and for example, 300 μm or less, or preferably 100 μm or less.

[0062] The thickness of the solid electrolyte layer 203 is preferably smaller than the thickness of the positive electrode layer 201 and the thickness of the negative electrode layer 202 .

[0063] [Current Collector] The current collector 21 is stacked on the cell 20. Specifically, as shown in FIG. 2 , each of the multiple current collectors 21 is stacked alternately with each of the multiple cells 20. The multiple current collectors 21 include a positive electrode current collector 21A and a negative electrode current collector 21B. The positive electrode current collector 21A contacts the positive electrode layer 201 of the cell 20. In FIG. 2 , the positive electrode current collector 21A is indicated by 211A and 212A. The negative electrode current collector 21B contacts the negative electrode layer 202 of the cell 20. In FIG. 2 , the negative electrode current collector 21B is indicated by 211B and 212B.

[0064] In this embodiment, as shown in FIG. 2 , the cells 20 and the current collectors 21 are stacked in the following order from one side to the other in the thickness direction: the first positive electrode current collector 211A, the first cell 20A, the first negative electrode current collector 211B, the second cell 20B, the second positive electrode current collector 212A, the third cell 20C, and the second negative electrode current collector 212B.

[0065] Specifically, the first negative electrode current collector 211B is disposed between the negative electrode layer 202 of the first cell 20A and the negative electrode layer 202 of the second cell 20B. Furthermore, the second positive electrode current collector 212A is disposed between the positive electrode layer 201 of the second cell 20B and the positive electrode layer 201 of the third cell 20C. That is, one current collector 21 is disposed between two cells 20 in the thickness direction. That is, the cells and current collectors are stacked in a parallel arrangement in a sheet-by-sheet stacking type.

[0066] In this embodiment, the cells and current collectors are stacked in a parallel arrangement in a sheet-by-sheet stacking manner, but a series arrangement in a sheet-by-sheet stacking manner may also be used. Furthermore, instead of the sheet-by-sheet stacking manner, a zigzag-folded arrangement may also be used. Although not shown, the sheet-by-sheet stacking manner in a series arrangement involves stacking multiple cells 20 in series in the thickness direction via internal current collecting layers, with the positive electrode current collector 21A disposed on the top surface in the thickness direction and the negative electrode current collector 21B disposed on the bottom surface in the thickness direction. A specific example of a stacked battery in a series arrangement in a sheet-by-sheet stacking manner is the stacked solid-state battery described in International Publication No. 2012 / 020700. Furthermore, although not shown, in a zigzag-folded stacked battery, a long current collector 21 is folded zigzag, and the cells 20 are arranged between the zigzag-folded current collectors 21. A specific example of a zigzag-folded stacked battery is the all-solid-state battery described in Japanese Patent Application Laid-Open No. 2020-113434.

[0067] The current collector 21 has a conductor 31, an insulating member 32, and an adhesive layer (not shown). The current collector 21 does not necessarily have to have the insulating member 32 or the adhesive layer.

[0068] The conductor 31 is made of, for example, metal and includes, for example, a laminated portion 311 and a current collecting tab 312. The conductor 31 does not necessarily have to include the current collecting tab 312.

[0069] The laminated portion 311 extends in a first direction and a second direction. The first direction is perpendicular to the thickness direction. The second direction is perpendicular to both the first direction and the thickness direction. The laminated portion 311 has a sheet shape. The laminated portion 311 has one side and the other side in the thickness direction. In other words, the conductor 31 has one side and the other side in the thickness direction. The laminated portion 311 contacts the cell 20. When the current collector 21 is a positive electrode current collector 21A, the laminated portion 311 (positive electrode laminated portion 311A) contacts the positive electrode layer 201 of the cell 20. When the current collector 21 is a negative electrode current collector 21B, the laminated portion 311 (negative electrode laminated portion 311B) contacts the negative electrode layer 202 of the cell 20. The laminated portion 311 has a substantially rectangular shape when viewed in the thickness direction. The laminated portion 311 has a plurality of edges e1, e2, e3, and e4. The edges e1, e2, e3, and e4 are continuous. As will be described later, the edges e1, e2, e3, and e4 of the laminated portion 311 face the edges E1, E2, E3, and E4 of the laminate film 4, respectively.

[0070] Edge e1 is disposed at one end of the laminated portion 311 in the first direction. Edge e1 extends in the second direction. Edge e1 has a linear shape. Edge e2 is disposed at the other end of the laminated portion 311 in the first direction. Edge e2 extends in the second direction. Edge e2 has a linear shape. Edge e3 is disposed at one end of the laminated portion 311 in the second direction. Edge e3 extends in the first direction. Edge e3 has a linear shape. Edge e4 is disposed at the other end of the laminated portion 311 in the second direction. Edge e4 extends in the first direction. Edge e4 has a linear shape.

[0071] The current collecting tab 312 is disposed on an edge of the laminated portion 311. For example, the current collecting tab 312 is disposed on an edge e3 on one side of the laminated portion 311 in the second direction. The current collecting tab 312 protrudes from the edge e3 of the laminated portion 311.

[0072] In this embodiment, the current collecting tab 312 has a substantially rectangular flat plate shape. The current collecting tab 312 does not contact the cell 20. When the current collector 21 is a positive electrode current collector 21A, the conductor 31 has a positive electrode current collecting tab 312A as the current collecting tab 312. When the current collector 21 is a negative electrode current collector 21B, the conductor 31 has a negative electrode current collecting tab 312B as the current collecting tab 312. When the cell 20, the positive electrode current collector 21A, and the negative electrode current collector 21B are stacked, the protruding direction (one direction in the second direction) of the positive electrode current collecting tab 312A is the same as the protruding direction (one direction in the second direction) of the negative electrode current collecting tab 312B, and the positive electrode current collecting tab 312A is positioned apart from the negative electrode current collecting tab 312B in the first direction. As shown in FIG. 1, when the cell 20, the positive electrode current collector 21A, and the negative electrode current collector 21B are stacked, the negative electrode current collector tab 312B does not overlap the positive electrode current collector tab 312A in the thickness direction.

[0073] The current collecting tab 312 may be formed of a separate member from the laminate portion 311 and joined to the laminate portion 311, or may be formed of the same member as the laminate portion 311 and joined to the laminate portion 311, or may be formed of the same member as the laminate portion 311 and by extending a portion of the edge of the laminate portion 311. In this embodiment, the current collecting tab 312 is formed of the same member as the laminate portion 311 and by extending a portion of the edge of the laminate portion 311.

[0074] As described above, the length of the current collecting tab 312 in the first direction is set appropriately within a range in which the positive electrode current collecting tab 312A and the negative electrode current collecting tab 312B do not come into contact with each other.

[0075] The length of the current collecting tab 312 in the second direction (length in the protruding direction) is not particularly limited as long as it is long enough to be connected to a tab lead 22 described later.

[0076] The thickness of the conductor 31 is, for example, 1 μm or more, or preferably 5 μm or more, and for example, 100 μm or less, or preferably 50 μm or less.

[0077] Examples of materials for the conductor 31 include copper (Cu), magnesium (Mg), stainless steel, titanium (Ti), iron (Fe), cobalt (Co), nickel (Ni), zinc (Zn), aluminum (Al), germanium (Ge), indium (In), lithium (Li), tin (Sn), and alloys thereof.

[0078] The insulating member 32 is laminated on one surface in the thickness direction of the conductor 31. More specifically, the insulating member 32 is disposed on the laminated portion 311 of the conductor 31. The insulating member 32 is laminated on the peripheral edge portion of the laminated portion 311 of the conductor 31. The insulating member 32 has a substantially rectangular frame shape when viewed in the thickness direction. The insulating member 32 extends along each edge e1, e2, e3, and e4 of the conductor 31. The insulating member 32 is not disposed on the current collecting tab 312 of the conductor 31.

[0079] When the positive electrode current collector 21A, the cell 20, and the negative electrode current collector 21B are stacked, the insulating member 32 is disposed around the cell 20. As shown in Fig. 2, when the positive electrode current collector 21A, the cell 20, and the negative electrode current collector 21B are stacked, the insulating member 32 is disposed between the conductor 31 of the positive electrode current collector 21A and the conductor 31 of the negative electrode current collector 21B in the thickness direction. When the positive electrode current collector 21A, the cell 20, and the negative electrode current collector 21B are stacked, the insulating member 32 insulates the positive electrode current collector 21A from the negative electrode current collector 21B.

[0080] The thickness of the insulating member 32 is thinner than the thickness of the cell 20. When the current collector 21 does not have an adhesive layer, the thickness of the insulating member 32 may be the same as the thickness of the cell 20. The thickness of the insulating member 32 is, for example, 50 μm or more, preferably 75 μm or more, and for example, 500 μm or less, preferably 400 μm or less.

[0081] Examples of materials for the insulating member 32 include polyethylene terephthalate and polyimide.

[0082] The adhesive layer is disposed between the conductor 31 and the insulating member 32 at the periphery of the conductor 31. The current collector 21 does not necessarily have to have an adhesive layer.

[0083] When the current collector 21 has an adhesive layer, the sum of the thickness of the adhesive layer and the thickness of the insulating member 32 is not more than the thickness of the cell 20. The thickness of the adhesive layer is, for example, 30 μm or more, preferably 50 μm or more, and for example, 300 μm or less, preferably 200 μm or less.

[0084] The adhesive layer is preferably insulating. Examples of materials for the adhesive layer include resins such as acrylic, polyimide, and silicone, and nonwoven fabrics impregnated with these resins.

[0085] [Tab Lead] The tab lead 22 includes a tab connection portion 221 that is connected to the current collector 21, and a lead portion 222 that is continuous with the tab connection portion 221 and protrudes from the peripheral edge of the laminate film 4. The tab lead 22 electrically connects the stacked battery 2 to the outside. The tab lead 22 includes the tab connection portion 221 and the lead portion 222 in that order in the protruding direction.

[0086] The tab lead 22 includes a positive electrode tab lead 22A electrically connected to the positive electrode current collector 21A and a negative electrode tab lead 22B electrically connected to the negative electrode current collector 21B. The positive electrode tab lead 22A is not connected to the negative electrode current collector 21B, and the negative electrode tab lead 22B is not connected to the positive electrode current collector 21A.

[0087] The positive electrode tab lead 22A includes a positive electrode tab connection portion 221A electrically connected to the positive electrode current collector 21A, and a positive electrode lead portion 222A that is continuous with the positive electrode tab connection portion 221A and protrudes from the peripheral edge of the laminate film 4. The negative electrode tab lead 22B includes a negative electrode tab connection portion 221B electrically connected to the negative electrode current collector 21B, and a negative electrode lead portion 222B that is continuous with the negative electrode tab connection portion 221B and protrudes from the peripheral edge of the laminate film 4.

[0088] Specifically, the tab connection portion 221 is electrically connected to the current collecting tab 312. Note that, in the current collector 21, when the conductor 31 does not include the current collecting tab 312, the tab connection portion 221 may be directly connected to the laminate portion 311. As shown in FIG. 2 , the tab connection portion 221 is electrically connected to the current collecting tab 312 so that the lead portion 222 extends in the same direction as the protruding direction of the current collecting tab 312 (the second direction). When the tab lead 22 is a positive electrode tab lead 22A, the positive electrode tab connection portion 221A is electrically connected to the positive electrode current collecting tab 312A. When the tab lead 22 is a negative electrode tab lead 22B, the negative electrode tab connection portion 221B is electrically connected to the negative electrode current collecting tab 312B.

[0089] The lead portion 222 is continuous with the tab connection portion 221. As will be described in detail later, the lead portion 222 protrudes from an edge E3 at the peripheral end of the laminate film 4 that faces the edge e3. As shown in FIG. 2 , the lead portion 222 extends in the same direction as the protruding direction of the current collecting tab 312 (the second direction), and protrudes from the edge E3 at the peripheral end of the laminate film 4.

[0090] The tab lead 22 has a generally rectangular flat plate shape. The protruding direction (one direction in the second direction) of the positive electrode tab lead 22A is the same as the protruding direction (one direction in the second direction) of the negative electrode tab lead 22B, and the positive electrode tab lead 22A is spaced apart from the negative electrode tab lead 22B in the second direction. As shown in FIG. 1 , the positive electrode tab lead 22A does not overlap with the negative electrode tab lead 22B in the thickness direction.

[0091] The lead portion 222 is made of the same material as the tab connection portion 221 and is continuous with it.

[0092] The material of the tab lead 22 is not particularly limited as long as it is usable as a lead wire for a battery, and examples thereof include pure metals and alloys. Examples of pure metals include copper, nickel, aluminum, gold, and platinum. Examples of alloys include alloys of the above pure metals, stainless steel, and titanium. The tab lead 22 may be plated. For example, the tab lead 22 may be a copper plate having a nickel-plated layer and a gold-plated layer.

[0093] The tab lead 22 has a thickness of, for example, 5 μm or more, or preferably 10 μm or more, and for example, 1000 μm or less, or preferably 200 μm or less.

[0094] The length of the tab lead 22 in the protruding direction is not particularly limited as long as it has a length sufficient to protrude from the peripheral edge of the laminate film 4 .

[0095] 1.2 Sealant The sealant 3 is disposed at the peripheral edge of the laminate film 4, between the inner peripheral surface of the laminate film 4 and the outer peripheral surface of the lead portion 222. The sealant 3 is bonded to the outer peripheral surface of the lead portion 222 and also to the inner peripheral surface of the laminate film 4. As will be described in detail later, the sealant 3 is heat-sealed to the inner peripheral surface of the laminate film 4 and the outer peripheral surface of the lead portion 222. The sealant 3 is bonded to a portion of the lead portion 222, and is not bonded to the tip of the lead portion 222 in the protruding direction. In other words, the tip of the lead portion 222 in the protruding direction is exposed.

[0096] 1 , a plurality of sealants 3 are provided. Specifically, one sealant 3 is disposed at the peripheral end (edge ​​E3) of the laminate film 4, between the inner peripheral surface of the laminate film 4 and the outer peripheral surface of the positive electrode lead portion 222A. Another sealant 3 is disposed at the peripheral end (edge ​​E3) of the laminate film 4, between the inner peripheral surface of the laminate film 4 and the outer peripheral surface of the negative electrode lead portion 222B. Furthermore, one sealant 3 contacts the entire outer peripheral surface of the positive electrode lead portion 222A, and the other sealant 3 contacts the entire outer peripheral surface of the negative electrode lead portion 222B.

[0097] The material of the sealant 3 is not particularly limited as long as it can insulate the laminate film 4 and the lead portion 222 so as to prevent short-circuiting. Examples of the material of the sealant 3 include heat-sealable resins (e.g., thermoplastic resins). Examples of heat-sealable resins include polyolefin resins, polyester resins, polycarbonate resins, polyphenylene ether resins, polyacetal resins, polystyrene resins, polyvinyl chloride resins, and polyvinyl acetate resins. The sealant 3 is preferably a polyolefin resin, and more preferably a polypropylene resin.

[0098] The material of the sealant 3 does not have to be the above-mentioned heat-sealing resin. Specifically, the material of the sealant 3 may be a thermosetting resin. Examples of the thermosetting resin include an epoxy resin and a urethane resin.

[0099] If the sealant 3 does not have thermal adhesive properties, that is, if the sealant 3 cannot thermally seal the inner circumferential surface of the laminate film 4 and the outer circumferential surface of the lead portion 222, an adhesive layer may be provided on the outer circumferential surface of the sealant 3. Examples of the adhesive layer include the same adhesive layers as those described for the current collector 21 above.

[0100] The thickness of the sealant is, for example, 25 μm or more, preferably 50 μm or more, and for example, 200 μm or less, preferably 100 μm or less.

[0101] The length of the sealant in the protruding direction of the lead portion 222 is not particularly limited as long as it is shorter than the length of the lead portion 222 of the tab lead 22 in the protruding direction of the lead portion 222 and is long enough to bond the inner surface of the laminate film 4 and the outer surface of the lead portion 222.

[0102] The length of the sealant in the first direction is preferably the same as or longer than the length of the tab lead 22 in the first direction.

[0103] 1.3 Laminate Film The laminate film 4 houses the battery stack 2.

[0104] The laminate film 4 includes a metal layer 41. The laminate film 4 preferably includes the metal layer 41 and a resin layer 42 on the inner peripheral surface of the metal layer 41. In this embodiment, the laminate film 4 includes the metal layer 41, the resin layer 42 disposed on the inner peripheral surface of the metal layer 41, and a second resin layer 43 disposed on the outer peripheral surface of the metal layer 41.

[0105] The metal layer 41 is disposed in the laminate film 4 between the resin layer 42 and the second resin layer 43. The metal layer 41 does not come into contact with the stacked battery 2.

[0106] The material of the metal layer 41 is not particularly limited as long as it is a metal that is commonly used in laminate films, and examples thereof include aluminum, copper, nickel, alloys thereof, and stainless steel. Aluminum is preferred.

[0107] The thickness of the metal layer 41 (portions other than the free end portion 411) is not particularly limited, but is, for example, 5 μm or more, preferably 20 μm or more, and for example, 100 μm or less, preferably 50 μm or less.

[0108] The resin layer 42 is disposed on the innermost peripheral surface of the laminate film 4. The resin layer 42 contacts the sealant at the peripheral edge of the laminate film 4, and contacts the battery stack 2 in the portion that houses the battery stack 2.

[0109] The material of the resin layer 42 is not particularly limited as long as it can insulate the metal layer 41 of the laminate film 4 from the lead portion 222 so as to prevent short-circuiting. Examples of the material of the resin layer 42 include resins. Examples of resins include polyolefin resins, polyester resins, polycarbonate resins, polyphenylene ether resins, polyacetal resins, polystyrene resins, polyvinyl chloride resins, polyvinyl acetate resins, polyamide resins, epoxy resins, and urethane resins. Polyolefin resins are preferred.

[0110] Examples of polyolefin resins include polyethylene resins and polypropylene resins, and polypropylene resins are preferred.

[0111] If the material of the resin layer 42 has heat-sealing properties, the sealant 3 can be heat-sealed to the laminate film 4 even if the sealant 3 does not have heat-sealing properties. Also, if the material of the resin layer 42 has heat-sealing properties, the peripheral edge of the laminate film 4 can be heat-sealed without the use of an adhesive.

[0112] The resin layer 42 has a thickness of, for example, 10 μm or more, preferably 30 μm or more, and for example, 200 μm or less, preferably 50 μm or less.

[0113] The total thickness (total thickness) of the sealant 3 and the resin layer 42 is, for example, 25 μm or more, or preferably 50 μm or more, and for example, 400 μm or less, or preferably 100 μm or less.

[0114] The total thickness (total thickness) of the sealant 3 and the resin layer 42 is preferably thicker (larger) than the length in the thickness direction of a burr 412 of the metal layer 41, which will be described later.

[0115] The second resin layer 43 is disposed on the outermost surface of the laminate film 4. The second resin layer 43 forms the exposed surface of the laminate film 4 and protects the laminate battery 1.

[0116] Examples of materials for the second resin layer 43 include resins. Examples of resins include polyolefin resins, polyester resins, polycarbonate resins, polyphenylene ether resins, polyacetal resins, polystyrene resins, polyvinyl chloride resins, polyvinyl acetate resins, polyamide resins, epoxy resins, and urethane resins. Polyamide resins are preferred. Examples of polyamide resins include nylon.

[0117] The materials of the resin layer 42 and the second resin layer 43 may be the same or different, and are preferably different.

[0118] The thickness of the second resin layer 43 is not particularly limited, but is, for example, 10 μm or more, preferably 20 μm or more, and for example, 200 μm or less, preferably 50 μm or less.

[0119] The total thickness of the laminate film 4 is not particularly limited, but is, for example, 40 μm or more, preferably 50 μm or more, and for example, 1000 μm or less, preferably 200 μm or less.

[0120] The laminate film 4 extends in a first direction and a second direction. As shown in FIG. 1 , the laminate film 4 has a substantially rectangular shape when viewed in the thickness direction. The laminate film 4 has multiple edges E1, E2, E3, and E4. The multiple edges E1, E2, E3, and E4 are continuous. The peripheral edge of the laminate film 4 is the combined portion of the multiple edges E1, E2, E3, and E4.

[0121] Edge E1 is located at one end of the laminate film 4 in the first direction. Edge E1 extends in the second direction. Edge E2 is located at the other end of the laminate film 4 in the first direction. Edge E2 extends in the second direction. Edge E3 is located at one end of the laminate film 4 in the second direction. Edge E3 extends in the first direction. Edge E4 is located at the other end of the laminate film 4 in the second direction. Edge E4 extends in the first direction.

[0122] The multiple edges e1, e2, e3, and e4 of the laminated portion 311 face the multiple edges E1, E2, E3, and E4 of the laminate film 4, respectively.

[0123] As shown in FIG. 1, at the edge E3 of the laminate film 4, the lead portion 222 protrudes.

[0124] The peripheral end surface of the laminate film 4 is, for example, flat. That is, on the peripheral end surface of the laminate film 4, the metal layer 41, the resin layer 42, and the second resin layer 43 are flush with each other.

[0125] In this embodiment, edges E1 and E2 of laminate film 4 have a substantially planar shape perpendicular to the first direction when viewed from the second direction. Edges E3 and E4 of laminate film 4 also have a substantially planar shape perpendicular to the second direction when viewed from the first direction.

[0126] At the peripheral edge of the laminate film 4, the free end 411 of the metal layer 41 has a burr 412 that is bent in the thickness direction.

[0127] At the edge E3 of the laminate film 4, the burrs 412 of the metal layer 41 face away from the lead portion 222. Specifically, the burrs 412 of the metal layer 41 face away from the lead portion 222 and the sealant 3 in the thickness direction. In other words, the burrs 412 of the metal layer 41 face toward the second resin layer 43.

[0128] In this embodiment, at the edges E1, E2, and E4 of the laminate film 4, the burrs 412 of the metal layer 41 may face toward the second resin layer 43 or may face away from the second resin layer 43.

[0129] The length of the burrs 412 of the metal layer 41 in the thickness direction is, for example, 10 μm or more, preferably 30 μm or more, and for example, 150 μm or less, preferably 100 μm or less, more preferably 50 μm or less.

[0130] The length of the burr 412 of the metal layer 41 in the thickness direction is the length of the free end 411 of the metal layer 41 in the thickness direction. Specifically, the length of the burr 412 of the metal layer 41 in the thickness direction is the length from the surface of the free end 411 of the metal layer 41 that faces the sealant 3 in the thickness direction to the tip of the metal layer 41. In other words, the length of the burr 412 of the metal layer 41 in the thickness direction is longer than the thickness of the metal layer 41 (portions other than the free end 411).

[0131] The length of the burr 412 of the metal layer 41 in the thickness direction is preferably thinner (smaller) than the combined thickness (total thickness) of the resin layer 42 and the sealant 3 .

[0132] The ratio of the thickness of the metal layer 41 (parts other than the free end 411) to the thickness-wise length of the burr 412 of the metal layer 41 (thickness of the metal layer 41 / thickness-wise length of the burr 412) is, for example, 0.5 or more, preferably 0.7 or more, more preferably 0.8 or more, even more preferably 0.9 or more, particularly preferably 0.95 or more, and also, for example, less than 1.

[0133] Furthermore, the difference between the thickness direction length of the burr 412 of the metal layer 41 and the thickness of the metal layer 41 (portion other than the free end 411) (thickness direction length of the burr 412 - thickness of the metal layer 41 (portion other than the free end 411)) is, for example, more than 0 μm and, for example, 50 μm or less, preferably 30 μm or less, more preferably 10 μm or less, and even more preferably 5 μm or less.

[0134] 1.4. Effects and Benefits (1) In the laminated battery 1 of the present disclosure, the sealant 3 is disposed at the peripheral edge of the laminated film 4 between the inner circumferential surface of the laminated film 4 and the outer circumferential surface of the lead portion 222, and the burrs 412 at the free end 411 of the metal layer 41 of the laminated film 4 face away from the lead portion 222. This prevents the burrs 412 at the free end 411 of the metal layer 41 from penetrating the sealant 3 and coming into contact with the lead portion 222, thereby preventing a short circuit between the laminated film 4 and the stacked battery 2. Specifically, in the laminated battery 1 of the present disclosure, although the metal layer 41 of the laminated film 4 has burrs 412, the burrs 412 at the metal layer 41 face away from the lead portion 222. In this way, the laminate battery 1 of the present disclosure does not require any special manufacturing process, and therefore can suppress short circuits between the laminate film 4 and the stacked battery 2 with a simpler manufacturing process than the battery of Patent Document 1. This also leads to savings in manufacturing space and costs.

[0135] (2) In one embodiment of the laminated battery 1 described above, the laminate film 4 further includes a resin layer 42 disposed on the inner circumferential surface of the metal layer 41. Therefore, even when the peripheral edge of the laminate film 4 is pressed for thermal fusion, the burrs 412 at the free end 411 of the metal layer 41 can be further prevented from coming into contact with the lead portion 222.

[0136] (3) In one embodiment of the laminated battery 1, the combined thickness (total thickness) of the sealant 3 and the resin layer 42 is greater than the thickness-wise length of the burr 412 of the metal layer 41. Therefore, even if the peripheral edge of the laminate film 4 is pressed for heat sealing and the orientation of the burr 412 at the free end 411 of the metal layer 41 changes, the sealant 3 and the resin layer 42 can prevent the burr 412 at the free end 411 of the metal layer 41 from coming into contact with the lead portion 222.

[0137] (4) In one embodiment of the laminated battery 1, the combined thickness (total thickness) of the sealant 3 and the resin layer 42 is 50 μm or greater. Therefore, even if the metal layer 41 of the laminate film 4 is thick, the sealant 3 and the resin layer 42 can further prevent burrs 412 at the free end 411 of the metal layer 41 from coming into contact with the lead portion 222.

[0138] (5) In one embodiment of the laminated battery 1 described above, the positive electrode lead portion 222A of the positive electrode tab lead 22A protrudes in the same direction as the negative electrode lead portion 222B of the negative electrode tab lead 22B. This makes it easier to connect the laminated battery 2 to the outside.

[0139] 2. Manufacturing Method of Laminated Battery One embodiment of the manufacturing method of the laminated battery of the present disclosure will be described with reference to Figures 5A to 5D and Figures 6A and 6B. Note that the method for manufacturing the laminated battery 1 of the above embodiment is one embodiment of the manufacturing method of the laminated battery.

[0140] The manufacturing method of the laminated battery includes a step of cutting the laminated film 4 (cutting step), a step of preparing the stacked battery 2 (stacked battery preparation step), a step of arranging the stacked battery 2 and the laminated film 4 (arrangement step), and a step of heat-sealing the peripheral edge of the laminated film 4 (heat-sealing step).

[0141] 5A, the laminate film 4 having the metal layer 41 is cut. Specifically, the laminate film 4 is unwound from a roll of the laminate film 4 and cut to a size corresponding to the laminate battery 1.

[0142] The cutting method is not particularly limited, but may be, for example, cutting using a cutting machine. Note that Fig. 5A shows a blade of a cutting machine or the like.

[0143] When the laminate film 4 having the metal layer 41 is cut, burrs 412 that are bent in the thickness direction (cutting direction) are generated at the free end portion 411 of the metal layer 41 .

[0144] (Stacked Battery Preparation Process) In this embodiment, the stacked battery preparation process includes a process of preparing the cells 20 and the current collectors 21 (first process), a process of preparing the tab leads 22 and joining the sealant 3 to the lead portions 222 of the tab leads 22 (second process), and a process of connecting the tab connection portions 221 of the tab leads 22 joined with the sealant 3 to the current collectors 21 (third process).

[0145] [First Step] As shown in FIG. 5B , a cell 20 having a positive electrode layer 201, a negative electrode layer 202, and a solid electrolyte layer 203 disposed between the positive electrode layer 201 and the negative electrode layer 202, and a current collector 21 to be laminated on the cell 20 are prepared.

[0146] Specifically, a plurality of cells 20 and a plurality of current collectors 21 are alternately stacked. In Fig. 5B, the first positive electrode current collector 211A, the first cell 20A, the first negative electrode current collector 211B, the second cell 20B, the second positive electrode current collector 212A, the third cell 20C, and the second negative electrode current collector 212B are stacked in this order from one side to the other in the thickness direction of the cells 20 and the current collectors 21.

[0147] In the first step, the multiple positive electrode current collector tabs 312A (the positive electrode current collector tabs 312A of the first positive electrode current collector 211A and the positive electrode current collector tabs 312A of the second positive electrode current collector 212A) may be joined so as to be electrically connected to each other. Also, the multiple negative electrode current collector tabs 312B (the negative electrode current collector tabs 312B of the first negative electrode current collector 211B and the negative electrode current collector tabs 312B of the second negative electrode current collector 212B) may be joined so as to be electrically connected to each other. The method for joining the multiple positive electrode current collector tabs 312A and the method for joining the multiple negative electrode current collector tabs 312B are not particularly limited as long as they can be joined so as to be electrically connected. Examples include a method of joining only a portion of each current collector tab 312 using an adhesive or a heat-sealing resin, and an ultrasonic joining method.

[0148] [Second Step] As shown in FIG. 5C, a tab lead 22 including a tab connection portion 221 and a lead portion 222 continuous with the tab connection portion 221 is prepared, and a sealant 3 is bonded to the lead portion 222.

[0149] Specifically, two sets of tab leads 22 are prepared, each including a tab connection portion 221 and a lead portion 222 continuous with the tab connection portion 221. Next, the sealant 3 is bonded to each of the lead portions 222 of the two sets of tab leads 22. The sealant 3 is bonded to a portion of the lead portion 222 (a portion midway in the second direction) so as to contact the entire outer circumferential surface of the lead portion 222. The sealant 3 is not bonded to the tip of the lead portion 222 in the protruding direction (the tip opposite the tab connection portion 221).

[0150] [Third Step] As shown in FIG. 5D, the tab connection portion 221 of the tab lead 22 to which the sealant 3 is bonded is connected to the current collector 21.

[0151] Specifically, one tab connection portion 221 of the tab leads 22 to which the sealant 3 is bonded is electrically connected to the positive electrode current collector tab 312A. The tab lead 22 connected to the positive electrode current collector tab 312A is the positive electrode tab lead 22A. Furthermore, the other tab connection portion 221 of the tab leads 22 to which the sealant 3 is bonded is electrically connected to the negative electrode current collector tab 312B. The tab lead 22 connected to the negative electrode current collector tab 312B is the negative electrode tab lead 22B.

[0152] The connection method is not particularly limited as long as it provides an electrical connection, and examples include a method of joining only a portion of the tab connection portion 221 using adhesive or heat-sealing resin, and an ultrasonic joining method.

[0153] Furthermore, in the first step, if the multiple positive electrode current collecting tabs 312A are not joined so as to be electrically connected to one another, they may be joined together when connecting the positive electrode tab lead 22A. The same applies to the multiple negative electrode current collecting tabs 312B.

[0154] In this manner, the stacked battery 2 to which the sealant 3 is bonded is prepared.

[0155] (Arrangement Step) As shown in FIG. 6A, the battery stack 2 to which the sealant 3 is bonded and the laminate film 4 are arranged.

[0156] Specifically, two laminate films 4 are prepared and arranged so that the laminate films 4 sandwich the stacked battery 2 to which the sealant 3 is bonded. At this time, the lead portions 222 protrude from the peripheral end (edge ​​E3) of the laminate film 4. The lead portions 222 protrude in a direction (second direction) perpendicular to the direction in which the edge E3 of the laminate film 4 extends (first direction). The sealant 3 is also located between the inner peripheral surface of the laminate film 4 and the outer peripheral surface of the lead portions 222.

[0157] Furthermore, the two laminate films 4 are selectively positioned so that the peripheral edge of the laminate film 4 where the burrs 412 of the metal layer 41 generated during the cutting process face the second resin layer 43 is positioned at a position where the lead portion 222 protrudes (in this embodiment, the peripheral edge of the laminate film 4 where the burrs 412 of the metal layer 41 generated during the cutting process face the second resin layer 43 is positioned at the edge E3). In other words, the burrs 412 of the metal layer 41 of the laminate film 4 face the opposite side from the lead portion 222. Note that the thickness direction orientation of the burrs 412 of the metal layer 41 at the peripheral edge of the laminate film 4 other than the position where the lead portion 222 protrudes is not particularly limited.

[0158] (Heat-sealing step) As shown in FIG. 6B, the peripheral edges of the two laminate films 4 are heat-sealed.

[0159] Specifically, first, edge E3 of laminate film 4 from which lead portion 222 protrudes is heat-sealed. Next, edges E1 and E2 of laminate film 4 are heat-sealed. Next, edge E4 of laminate film 4 opposite the peripheral end from which lead portion 222 protrudes is heat-sealed while drawing a vacuum.

[0160] In this manner, the laminate battery 1 is produced.

[0161] Although not shown, the manufacturing method of the laminated battery 1 may include a removal step. Specifically, the removal step is a step of removing excess laminate film 4 from the peripheral edge of the laminated film 4 after the heat sealing step.

[0162] (Effects) (1) In the manufacturing method of the laminate battery disclosed herein, when the laminate film 4 including the metal layer 41 is cut, burrs 412 that bend in the thickness direction are generated at the free end 411 of the metal layer 41, but the method includes a step of positioning the laminate battery 2 and the laminate film 4 so that the burrs 412 of the metal layer 41 face away from the lead portion 222 of the laminate battery 2. Therefore, the above-described laminate battery 1 can be manufactured using simple equipment and steps.

[0163] (2) In one embodiment of the manufacturing method for the laminated battery described above, the laminated battery preparation process includes a step (first step) of preparing the cells 20 and the current collectors 21, a step (second step) of preparing the tab leads 22 and joining the sealant 3 to the lead portions 222 of the tab leads 22, and a step (third step) of connecting the tab connection portions 221 of the tab leads 22 joined with the sealant 3 to the current collectors 21. This allows selective use of tab leads 22 that match the shapes of the laminated battery 2 and the laminate film 4, making it easy to connect the laminated battery 2 to the outside.

[0164] 3. Modifications In the modification examples, the same components and steps as those in the embodiment of the laminate battery and the embodiment of the manufacturing method for the laminate battery are designated by the same reference numerals, and detailed descriptions thereof will be omitted. Furthermore, unless otherwise specified, the modification examples can achieve the same effects as those in the embodiment of the laminate battery and the embodiment of the manufacturing method for the laminate battery. Furthermore, the embodiment of the laminate battery or the embodiment of the manufacturing method for the laminate battery can be appropriately combined with the modification examples.

[0165] 3.1 First Modification In the above-described embodiment of the laminate battery and the embodiment of the manufacturing method of the laminate battery, the tab lead 22 is electrically connected to the current collecting tab 312, but the present invention is not limited to this.

[0166] [First Modification of Laminated Battery] In a first modification of the laminated battery, the current collecting tab 312 forms the tab lead 22. When the current collecting tab 312 forms the tab lead 22, the current collecting tab 312 has the function of the tab lead 22 (e.g., electrically connecting the laminated battery 2 to the outside) and is considered to be the tab lead 22. In other words, the current collector 21 does not have a current collecting tab 312.

[0167] 7 , the tab lead 22 is disposed at an edge of the laminated portion 311. For example, the tab lead 22 is disposed at an edge e3 on one side of the laminated portion 311 in the second direction. The tab lead 22 protrudes from the edge e3 of the laminated portion 311.

[0168] The tab lead 22 is electrically connected to the laminated portion 311 of the current collector 21. In this case, the tab lead 22 may be formed of a separate member from the laminated portion 311 and joined to the laminated portion 311, or may be formed of the same member as the laminated portion 311 and joined to the laminated portion 311, or may be formed of the same member as the laminated portion 311 and by extending a portion of the edge of the laminated portion 311. In this modification, the tab lead 22 is formed of the same member as the laminated portion 311 and by extending a portion of the edge of the laminated portion 311.

[0169] The tab lead 22 has a substantially rectangular flat plate shape. The tab lead 22 does not contact the cell 20. The tab lead 22 connected to the laminate portion 311 of the positive electrode current collector 21A is a positive electrode tab lead 22A. The positive electrode tab lead 22A includes a positive electrode tab connection portion 221A electrically connected to the laminate portion 311 of the positive electrode current collector 21A, and a positive electrode lead portion 222A that is continuous with the positive electrode tab connection portion 221A and protrudes from the peripheral edge of the laminate film 4. The tab lead 22 connected to the laminate portion 311 of the negative electrode current collector 21B is a negative electrode tab lead 22B. The negative electrode tab lead 22B includes a negative electrode tab connection portion 221B electrically connected to the negative electrode current collector 21B, and a negative electrode lead portion 222B that is continuous with the negative electrode tab connection portion 221B and protrudes from the peripheral edge of the laminate film 4. The positive electrode tab lead 22A is not connected to the negative electrode current collector 21B, and the negative electrode tab lead 22B is not connected to the positive electrode current collector 21A.

[0170] When the positive electrode current collector 21A, the cell 20, and the negative electrode current collector 21B are stacked, the protruding direction of the positive electrode tab lead 22A (one direction in the second direction) is the same as the protruding direction of the negative electrode tab lead 22B (one direction in the second direction), and the positive electrode tab lead 22A is spaced apart from the negative electrode tab lead 22B in the first direction. As shown in Fig. 7 , when the positive electrode current collector 21A, the cell 20, and the negative electrode current collector 21B are stacked, the positive electrode tab lead 22A does not overlap with the negative electrode tab lead 22B in the thickness direction.

[0171] As described above, the length of the tab lead 22 in the first direction is set appropriately within a range in which the positive electrode tab lead 22A and the negative electrode tab lead 22B do not come into contact with each other.

[0172] The length of the tab lead 22 in the second direction (length in the protruding direction) is not particularly limited as long as it has a length sufficient to protrude from the peripheral end (edge ​​E3) of the laminate film 4.

[0173] (Operation and Effect) In the first modified example of the laminated battery, the tab lead 22 is directly connected to the laminated portion 311 of the current collector 21. This ensures a reliable electrical connection between the laminated battery 2 and the tab lead 22, and ultimately ensures a more reliable electrical connection between the laminated battery 2 and the outside.

[0174] [First Variant of the Manufacturing Method of a Laminated Battery] In the first variant of the manufacturing method of a laminated battery, the laminated battery preparation process includes a process (first' process) of preparing a current collector 21 having a cell 20 and a tab lead 22, and a process (second' process) of joining a sealant 3 to the lead portion 222 of the tab lead 22.

[0175] (Step 1') Specifically, first, a cell 20 is prepared, which has a positive electrode layer 201, a negative electrode layer 202, and a solid electrolyte layer 203 disposed between the positive electrode layer 201 and the negative electrode layer 202. Then, a current collector 21 is prepared, which has a tab lead 22 including a tab connection portion 221 and a lead portion 222 continuous with the tab connection portion 221.

[0176] An example of a current collector 21 having a tab lead 22 is the current collector 21 shown in the first modified example of the laminated battery described above, in which the tab lead 22 is made of the same material as the laminated portion 311 and is formed by extending a portion of the edge of the laminated portion 311.

[0177] Next, the plurality of cells 20 and the plurality of current collectors 21 are alternately stacked. For example, in the thickness direction of the cells 20 and the current collectors 21, the first positive electrode current collector 211A, the first cell 20A, the first negative electrode current collector 211B, the second cell 20B, the second positive electrode current collector 212A, the third cell 20C, and the second negative electrode current collector 212B are stacked in this order from one side to the other.

[0178] The positive electrode current collector 21A has a positive electrode tab lead 22A, and the negative electrode current collector 21B has a negative electrode tab lead 22B.

[0179] (Second' step) The sealant 3 is bonded to the lead portion 222 of the tab lead 22 .

[0180] Specifically, the sealant 3 is bonded to each of the positive electrode tab lead 22A and the negative electrode tab lead 22B. The sealant 3 is bonded to a part of the lead portion 222 of each tab lead 22 so as to contact the entire outer circumferential surface of the lead portion 222. The sealant 3 is not bonded to the tip of the lead portion 222 in the protruding direction (the tip opposite the tab connection portion 221).

[0181] The positive electrode tab leads 22A are joined so as to be electrically connected to one another. The negative electrode tab leads 22B are joined so as to be electrically connected to one another. The method for joining the positive electrode tab leads 22A and the method for joining the negative electrode tab leads 22B are not particularly limited as long as they can be joined so as to be electrically connected. The joining may be performed using a sealant 3 in the second' step, or ultrasonic joining may be performed in the first' step.

[0182] (Operation and Effect) In the first modified method of manufacturing a laminated battery, the tab lead 22 is directly connected to the laminated portion 311 of the current collector 21 (the tab lead 22 extends from the current collector 21). In other words, there is no need to prepare a separate tab lead 22. This further simplifies the manufacturing process.

[0183] 3.2 Second Modification In the above-described embodiment of the laminated battery, the metal layer 41, the resin layer 42, and the second resin layer 43 are flush with each other on the peripheral end surface of the laminated film 4, but the present invention is not limited to this.

[0184] Specifically, as shown in Figure 8, the peripheral edge (edge ​​E3) of the laminate film 4 may be inclined in the opposite direction (other direction of the second direction) to the protruding direction of the lead portion 222 (one direction of the second direction) as it approaches the tip of the burr 412 of the metal layer 41.

[0185] In this case, at the peripheral edge of the laminate film 4, the resin layer 42 protrudes more than the metal layer 41 in the protruding direction (one direction of the second direction) of the lead portion 222. Also, the metal layer 41 protrudes more than the second resin layer 43 in the protruding direction (one direction of the second direction) of the lead portion 222.

[0186] Furthermore, the metal layer 41 protrudes in the thickness direction in the direction in which the lead portion 222 protrudes (in one direction, the second direction) as it approaches the lead portion 222 .

[0187] The angle of inclination is not particularly limited, and is adjusted appropriately depending on the length in the second direction when the laminate film 4 is heat-sealed.

[0188] (Effects) (1) In the second modification, the peripheral edge (edge ​​E3) of the laminate film 4 is inclined in the opposite direction (other second direction) to the protruding direction of the lead portion 222 (one direction in the second direction) toward the tip of the burr 412 of the metal layer 41. In other words, the metal layer 41 protrudes in the thickness direction in the protruding direction of the lead portion 222 (one direction in the second direction) toward the lead portion 222. Therefore, even when the laminate film 4 is heat-sealed and pressed, the metal layer 41, in addition to the sealant 3 and resin layer 42, is present between the burr 412 and the lead portion 222, further suppressing short circuits between the laminate film 4 and the stacked battery 2.

[0189] (2) In the second modification, the resin layer 42 at the peripheral edge of the laminate film 4 protrudes beyond the metal layer 41 in the protruding direction of the lead portion 222 (the second direction). Therefore, even when the laminate film 4 is heat-sealed and pressed, the resin layer 42 can be reliably positioned between the burrs 412 and the lead portion 222, and short circuits between the laminate film 4 and the stacked battery 2 can be more reliably prevented.

[0190] 3.2 Third Modification In one embodiment of the laminate battery described above, the positive electrode current collector tab 312A and the negative electrode current collector tab 312B protrude in the same direction (specifically, one direction in the second direction). Consequently, the positive electrode tab lead 22A and the negative electrode tab lead 22B also protrude in the same direction (specifically, one direction in the second direction) from the edge E3 of the laminate film 4. However, this is not limiting.

[0191] The positive electrode tab lead 22A and the negative electrode tab lead 22B may protrude in different directions from the peripheral end portions (edges) of different laminate films 4. In other words, the protruding direction of the positive electrode lead portion 222A of the positive electrode tab lead 22A is different from the protruding direction of the negative electrode lead portion 222B of the negative electrode tab lead 22B.

[0192] 9 , the positive electrode tab lead 22A may protrude in one direction in the second direction from an edge E3 of the laminate film 4, and the negative electrode tab lead 22B may protrude in the other direction in the second direction from an edge E4 of the laminate film 4. In other words, the protruding direction of the positive electrode lead portion 222A of the positive electrode tab lead 22A is opposite to the protruding direction of the negative electrode lead portion 222B of the negative electrode tab lead 22B.

[0193] At this time, at the peripheral end portions (edges E3 and E4) of each laminate film 4, the sealant 3 is positioned between the inner surface of the laminate film 4 and the outer surface of each lead portion 222, and the burrs 412 of the metal layer 41 of the laminate film 4 face opposite to each lead portion 222.

[0194] (Operation and Effect) In the third modified example, the protruding direction of the positive electrode lead portion 222A of the positive electrode tab lead 22A is different from the protruding direction of the negative electrode lead portion 222B of the negative electrode tab lead 22B. Therefore, it is possible to reliably prevent the positive electrode tab lead 22A and the negative electrode tab lead 22B from contacting each other.

[0195] The present disclosure will be described in more detail below with reference to examples, comparative examples, and reference examples. It should be noted that the present disclosure is not limited to the examples, comparative examples, and reference examples. The specific numerical values ​​of the blending ratios (content ratios), physical property values, parameters, etc. used in the following description can be replaced with the upper limit (a numerical value defined as "equal to or less than") or lower limit (a numerical value defined as "equal to or more than" or "exceeding") of the corresponding blending ratios (content ratios), physical property values, parameters, etc. described in the above "Modes for Carrying Out the Invention."

[0196] Example 1 (Cutting Process) A roll of laminate film (thickness: approximately 130 μm) was unwound and cut into 100 mm x 100 mm pieces using a cutter. The laminate film had a resin layer made of polypropylene resin, a metal layer made of aluminum, and a second resin layer made of nylon, arranged in that order in the thickness direction. The resin layer was approximately 50 μm thick, the metal layer (excluding the free end) was approximately 50 μm thick, and the second resin layer was approximately 30 μm thick.

[0197] When the laminate film was cut, burrs were generated at the free ends of the metal layers of the cut laminate film, bending in the cutting direction (thickness direction). The length of the burrs in the thickness direction was approximately 60 to 100 μm.

[0198] (Stacked Battery Preparation Step) Next, a stacked battery was prepared, which included a cell (thickness: approximately 500 μm) having a positive electrode layer, a negative electrode layer, and a solid electrolyte layer disposed between the positive electrode layer and the negative electrode layer, a current collector (thickness: approximately 20 μm) stacked on the cell, and a tab lead connected to the current collector.

[0199] More specifically, a tab lead having a tab connection portion and a lead portion continuous with the tab connection portion was connected to the current collector. The tab lead was made of the same material as the laminated portion of the current collector, and was formed by extending a portion of the edge of the laminated portion.

[0200] The stacked battery includes a plurality of cells and a plurality of current collectors arranged alternately in the thickness direction. The current collectors include a negative electrode current collector arranged in contact with the negative electrode layer and a positive electrode current collector arranged in contact with the positive electrode layer. The positive electrode current collector has a positive electrode tab lead, and the negative electrode current collector has a negative electrode tab lead.

[0201] Specifically, a first positive electrode current collector having an insulating member at its peripheral edge and a first positive electrode tab lead was prepared, and a first cell was placed within the insulating member so that the positive electrode layer of the first cell contacted the conductor of the first positive electrode current collector. Then, a first negative electrode current collector having an insulating member at its peripheral edge and a first negative electrode tab lead was stacked so that the negative electrode layer of the first cell contacted the conductor of the first negative electrode current collector. A second cell was stacked so that the negative electrode layer of the second cell contacted the conductor of the first negative electrode current collector. A second positive electrode current collector having an insulating member at its peripheral edge and a second positive electrode tab lead was stacked so that the positive electrode layer of the second cell contacted the conductor of the second positive electrode current collector. A third cell was stacked so that the positive electrode layer of the third cell contacted the conductor of the second positive electrode current collector. Furthermore, a second negative electrode current collector equipped with a second negative electrode tab lead was stacked on top of the third cell so that the negative electrode layer of the third cell was in contact with the conductor of the second negative electrode current collector.

[0202] The positive electrode tab leads and the negative electrode tab leads were spaced apart in the first direction so as not to overlap each other. The first positive electrode tab lead and the second positive electrode tab lead were arranged to overlap each other when viewed from the thickness direction, and the first negative electrode tab lead and the second negative electrode tab lead were arranged to overlap each other when viewed from the thickness direction. Furthermore, each positive electrode tab lead and each negative electrode tab lead both extended in the second direction.

[0203] Next, a positive electrode tab lead was joined to each positive electrode current collector, and a negative electrode tab lead was joined to each negative electrode current collector.

[0204] The thickness (total thickness) of each tab lead was about 50 μm, and the length of the tab lead in the protruding direction was about 10 to 50 mm.

[0205] Next, a sealant was bonded to the lead portion of each joined tab lead, that is, a positive electrode tab lead bonded with a sealant and a negative electrode tab lead bonded with a sealant were obtained.

[0206] The thickness of the sealant was approximately 100 μm.

[0207] In this way, a laminated battery with a sealant bonded thereto was prepared.

[0208] (Arrangement Step) The battery stack to which the sealant was bonded was arranged so as to be sandwiched between two laminate films.

[0209] Specifically, a stacked battery with a sealant bonded to it was placed on one laminate film, and another laminate film was placed on top of the stacked battery. At this time, the two laminate films were arranged so that the lead portions bonded to the sealant protruded from the peripheral edges of the laminate film. The sealant was also positioned between the inner circumferential surface of the laminate film and the outer circumferential surface of each lead portion. Furthermore, the laminate film was arranged so that burrs generated during the cutting process of the laminate film faced away from the lead portions.

[0210] (Heat-sealing process) Next, the peripheral edges of the two laminate films were heat-sealed. Specifically, first, the peripheral edges of the laminate films from which the leads protruded were heat-sealed. Next, the peripheral edges of the laminate films from which the leads protruded were heat-sealed except for the peripheral edges from which the leads protruded and the peripheral edge opposite to the peripheral edge. Next, the peripheral edge of the laminate films from which the leads protruded was heat-sealed while evacuating.

[0211] (Removal step) Next, unnecessary portions were removed from the laminate film of the fabricated laminate battery. Specifically, unnecessary portions of the laminate film from which the leads protruded were removed from the peripheral edge of the laminate film other than the peripheral edge from which the leads protruded using a cutter.

[0212] In this manner, the laminate battery of Example 1 was produced.

[0213] Comparative Example 1 A laminated battery was fabricated in the same manner as in Example 1, except that in the placement process, burrs on the free end of the metal layer, which were generated in the cutting process of the laminate film, were placed so as to face each lead portion.

[0214] <Evaluation> (Continuity Test) Sixteen laminate batteries were prepared for each of Example 1 and Comparative Example 1. The reason why the thickness direction length of the burrs in the metal layer is indicated as a range is because 16 batteries were prepared for each of Example 1 and Comparative Example 1. A continuity test was performed on each of the laminate batteries for Example 1 and Comparative Example 1 to check for the occurrence of a short circuit. The probability of a short circuit occurring was then calculated.

[0215] As a result, no short circuit occurred in any of the laminate batteries of Example 1, and the probability of short circuit occurrence was 0%. On the other hand, short circuit occurred in some of the laminate batteries of Comparative Example 1, and the probability of short circuit occurrence was 30% or more.

[0216] The above inventions are provided as exemplary embodiments of the present disclosure, but these are merely examples and should not be construed as limiting. Modifications of the present disclosure that are obvious to those skilled in the art are intended to be included within the scope of the following claims.

[0217] The laminate battery 1 of the present disclosure can be suitably used in various industrial fields that require all-solid-state batteries.

[0218] REFERENCE SIGNS LIST 1 Laminated battery 2 Laminated battery 20 Cell 201 Positive electrode layer 202 Negative electrode layer 203 Solid electrolyte layer 21 Current collector 22 Tab lead 221 Tab connection portion 222 Lead portion 3 Sealant 4 Laminate film 41 Metal layer 411 Free end portion 412 Burr

Claims

1. A laminated battery comprising a stacked battery, a sealant, and a laminate film that houses the stacked battery, wherein the stacked battery comprises a cell having a positive electrode layer, a negative electrode layer, and a solid electrolyte layer disposed between the positive electrode layer and the negative electrode layer, a current collector laminated on the cell, and a tab lead connected to the current collector, wherein the tab lead comprises a tab connection portion that connects to the current collector and a lead portion that is continuous with the tab connection portion and protrudes from a peripheral edge of the laminate film, the laminate film comprises a metal layer, and at the peripheral edge of the laminate film, the sealant is disposed between the inner peripheral surface of the laminate film and the outer peripheral surface of the lead portion, and the free end of the metal layer comprises a burr that is bent in the thickness direction, and the burr faces away from the lead portion.

2. The laminated battery according to claim 1, wherein the peripheral edge of the laminate film is inclined in a direction opposite to the protruding direction of the lead portion as it approaches the tip of the burr.

3. The laminate battery according to claim 1, wherein the laminate film further comprises a resin layer on the inner peripheral surface of the metal layer.

4. The laminated battery according to claim 3, wherein the resin layer protrudes beyond the metal layer at the peripheral edge of the laminated film in the direction in which the lead portions protrude.

5. The laminate battery according to claim 3 or 4, wherein the total thickness of the sealant and the resin layer is greater than the length of the burr in the thickness direction of the metal layer.

6. The laminate battery according to claim 5, wherein the total thickness of the sealant and the resin layer is 50 μm or more.

7. The laminate battery according to claim 1, wherein the current collector comprises a positive electrode current collector in contact with the positive electrode layer and a negative electrode current collector in contact with the negative electrode layer; the tab lead comprises a positive electrode tab lead connected to the positive electrode current collector and a negative electrode tab lead connected to the negative electrode current collector; the positive electrode tab lead comprises a positive electrode tab connection portion connected to the positive electrode current collector and a positive electrode lead portion that is continuous with the positive electrode tab connection portion and protrudes from the peripheral edge of the laminate film; the negative electrode tab lead comprises a negative electrode tab connection portion connected to the negative electrode current collector and a negative electrode lead portion that is continuous with the negative electrode tab connection portion and protrudes from the peripheral edge of the laminate film; and the protruding direction of the positive electrode lead portion is the same as the protruding direction of the negative electrode lead portion.

8. The laminate battery according to claim 1, wherein the current collector comprises a positive electrode current collector in contact with the positive electrode layer and a negative electrode current collector in contact with the negative electrode layer; the tab lead comprises a positive electrode tab lead connected to the positive electrode current collector and a negative electrode tab lead connected to the negative electrode current collector; the positive electrode tab lead comprises a positive electrode tab connection portion connected to the positive electrode current collector and a positive electrode lead portion that is continuous with the positive electrode tab connection portion and protrudes from the peripheral edge of the laminate film; the negative electrode tab lead comprises a negative electrode tab connection portion connected to the negative electrode current collector and a negative electrode lead portion that is continuous with the negative electrode tab connection portion and protrudes from the peripheral edge of the laminate film; and the protruding direction of the positive electrode lead portion differs from the protruding direction of the negative electrode lead portion.

9. A method for manufacturing a laminated battery, comprising: a step of cutting a laminated film having a metal layer to generate burrs bending in the thickness direction at the free end of the metal layer; a step of preparing a laminated battery having a cell having a positive electrode layer, a negative electrode layer, and a solid electrolyte layer disposed between the positive electrode layer and the negative electrode layer, a current collector laminated on the cell, a tab lead connected to the current collector and having a tab connection portion and a lead portion continuous with the tab connection portion, and a sealant bonded to the lead portion; a step of arranging the laminated battery having the sealant bonded and the laminated film at a peripheral edge of the laminated film so that the lead portion protrudes from the peripheral edge of the laminated film, the sealant is located between the inner peripheral surface of the laminated film and the outer peripheral surface of the lead portion, and the burr faces away from the lead portion; and a step of heat-sealing the peripheral edge of the laminated film from which the lead portion protrudes.

10. The method for manufacturing a laminated battery according to claim 9, wherein the step of preparing the laminated battery to which the sealant is bonded comprises the steps of: preparing the cell having the positive electrode layer, the negative electrode layer, and a solid electrolyte layer disposed between the positive electrode layer and the negative electrode layer, and the current collector to be laminated on the cell; preparing the tab lead having the tab connection portion and the lead portion continuous with the tab connection portion, and bonding the sealant to the lead portion; and connecting the tab connection portion to the current collector in the tab lead to which the sealant is bonded.

11. The method for producing a laminated battery according to claim 9, wherein the step of preparing a laminated battery to which the sealant is bonded comprises the steps of: preparing a laminated battery comprising the cell having the positive electrode layer, the negative electrode layer, and a solid electrolyte layer disposed between the positive electrode layer and the negative electrode layer; and the current collector laminated on the cell, the current collector having the tab lead including the tab connection portion and the lead portion continuous with the tab connection portion; and bonding the sealant to the lead portion.

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