Manufacturing method of case battery

Abstract

To provide a manufacturing method of a case battery in which a shape of a peripheral end portion of a case battery can be designed relatively flexibly.SOLUTION: A manufacturing method of a case battery is a manufacturing method of a case battery 1 including a laminated battery 2 having a cell 20, a housing 3 that accommodates the laminated battery 2 and has an opening 30 at least in a part of a peripheral end portion thereof, and a sealing body 4 that seals an opening part 30 of the housing 3. The manufacturing method of the case battery also includes a filling step of filling a resin composition 40 into the housing 3, a disposing step of disposing a block 5 so as to close the opening part 30 of the housing 3, and a curing step of curing the resin composition 40 in a state where the block 5 is disposed on the lower side in a gravity direction with respect to the housing 3.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a method for manufacturing a case battery. [Background technology]

[0002] Conventionally, there has been known an all-solid-state battery comprising an all-solid-state battery element having a negative electrode current collector layer, a negative electrode active material layer, a solid electrolyte layer, a positive electrode active material layer, and a positive electrode current collector layer; a metal exterior body having an opening at at least one end and housing the all-solid-state battery element; and a resin sealant that seals the opening of the metal exterior body and is in contact with the surface of the all-solid-state battery element that faces the opening of the metal exterior body (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2018-116917 Summary of the Invention [Problem to be solved by the invention]

[0004] The all-solid-state battery of Patent Document 1 has a drawback in that the shape of the resin sealant cannot be flexibly designed to match the structure of the all-solid-state battery, the shape of the tab lead provided as needed, and the like.

[0005] The present invention provides a method for manufacturing a case battery that allows relatively flexible design of the shape of the peripheral end of the case battery. [Means for solving the problem]

[0006] The present invention [1] is a method for manufacturing a case battery, which includes a laminated battery having cells each 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 casing that houses the laminated battery and has an opening in at least a portion of a peripheral edge, and a sealing body that seals the opening of the casing, and the method for manufacturing the case battery includes a sealing step of sealing the opening of the casing with the sealing body, and the sealing step includes a filling step of filling a resin composition into the casing, an arranging step of arranging a block so as to close the opening of the casing, and a curing step of curing the resin composition in a state in which the block is disposed downward in the direction of gravity relative to the casing.

[0007] According to this manufacturing method of the case battery, the sealing process includes a filling process of filling the housing with a resin composition, a placement process of placing a block so as to close the opening of the housing, and a curing process of curing the resin composition while the block is placed downward in the direction of gravity relative to the housing. Therefore, the resin composition can be cured in the opening of the housing according to the shape of the block. As a result, the shape of the peripheral edge of the case battery can be designed relatively flexibly.

[0008] The present invention [2] includes a method for manufacturing a case battery according to [1], wherein the housing has the opening only in a part of the peripheral edge.

[0009] According to this method for manufacturing a case battery, the housing has an opening only in a portion of the peripheral edge, which makes it possible to easily manufacture the case battery and reduce the risk of the stacked battery being exposed to external contamination.

[0010] The present invention [3] includes a method for manufacturing a case battery described in [1], wherein the opening of the housing has a first opening and a second opening that are spaced apart from each other.

[0011] According to this method for manufacturing a case battery, the opening of the housing has a first opening and a second opening that are spaced apart from each other, which allows for relatively flexible design of the connection position between the stacked battery and the outside in accordance with the application of the case battery.

[0012] The present invention [4] includes a method for manufacturing a case battery according to any one of [1] to [3], wherein the peripheral edge of the opening of the housing and one end face of the sealing body are flush with each other.

[0013] According to this method for manufacturing a case battery, the peripheral edge of the opening of the housing and one end face of the sealing body are flush with each other. This prevents the sealing body from coming off the opening of the housing due to external impact, etc. Furthermore, the manufactured case battery has an excellent appearance.

[0014] The present invention [5] includes the method for producing a case battery according to any one of [1] to [3], wherein the viscosity of the resin composition at 25° C. is 400 Pa·s or less.

[0015] According to this manufacturing method for a case battery, the opening is blocked by the block while the resin composition is cured, so that a resin composition with a low viscosity of 400 Pa·s or less at 25°C can be used. In addition, because the viscosity of the resin composition at 25°C is low, at 400 Pa·s or less, the shape of the peripheral edge of the case battery can be designed relatively flexibly to suit the application.

[0016] The present invention [6] includes the method for producing a case battery according to any one of [1] to [3], wherein the resin composition is a thermosetting resin composition.

[0017] According to this method for manufacturing a case battery, the resin composition is a thermosetting resin composition, so that the opening of the casing can be sealed in a simple manufacturing process.

[0018] The present invention [7] includes a method for manufacturing a case battery described in any one of [1] to [3], wherein the block is formed from an elastic material and has releasability with respect to the sealing body.

[0019] According to this method for manufacturing a case battery, the block is formed from an elastic material. Therefore, leakage of the resin composition from the opening of the housing can be suppressed. Furthermore, the block has releasability relative to the sealing body. Therefore, after the resin composition has hardened, the block can be easily peeled off. Furthermore, the manufactured case battery has excellent appearance.

[0020] The present invention [8] includes the method for manufacturing a case battery according to any one of [1] to [3], wherein the stacked battery further includes a current collector stacked on the cell and a tab lead connected to the current collector, the stacked battery is housed in the housing so that the tab lead protrudes from the opening of the housing, and in the arranging step, a plurality of the blocks are arranged so as to sandwich the tab lead and close the opening of the housing.

[0021] According to this method for manufacturing a case battery, the battery stack further includes tab leads, and the battery stack is housed in a housing so that the tab leads protrude from the opening of the housing. This allows for easy electrical connection between the battery stack and the outside via the tab leads. Furthermore, in the placement process, multiple blocks are placed so as to sandwich the tab leads and close the opening of the housing. This allows for easy sealing of the opening of the housing while allowing the tab leads to protrude from the housing. Furthermore, since there is no need to separately seal the tab leads, the process can be simplified.

[0022] The present invention [9] includes the method for manufacturing a case battery according to [8], wherein the connection portion between the current collector and the tab lead is embedded in the sealing body.

[0023] According to this manufacturing method for a case battery, the connection portion between the current collector and the tab lead is embedded in the sealing body, which fixes the positions of the current collector and the tab lead and prevents breakage of the connection portion due to vibration or the like.

[0024] The present invention

[10] includes the method for manufacturing a case battery according to any one of [1] to [3], wherein in the filling step, the filling amount V of the resin composition is 50 volume % or less relative to the difference (V0-V1) between the volume V0 inside the casing and the volume V1 of the stacked battery.

[0025] According to this manufacturing method for a case battery, the filling amount V of the resin composition in the filling step is 50% by volume or less of the difference (V0-V1) between the volume V0 inside the casing and the volume V1 of the laminated battery, which allows for a reduction in the weight of the case battery and also reduces costs.

[0026] The present invention

[11] includes the method for producing a case battery according to any one of [1] to [3], wherein the case is heated to 50°C or higher and 150°C or lower in the filling step.

[0027] According to this manufacturing method for a case battery, in the filling step, the housing is heated to a temperature of 50°C or higher and 150°C or lower, the temperature of the resin composition. Therefore, excessive expansion of the air inside the housing due to heating for curing the resin composition can be suppressed, and air leakage from between the resin composition and the block can be suppressed.

[0028] The present invention

[12] includes a method for manufacturing a case battery according to any one of [1] to [3], wherein at least one selected from the group consisting of the casing and the sealing body has a through hole.

[0029] According to this method for manufacturing a case battery, at least one selected from the group consisting of the housing and the sealing body is provided with a through-hole, so that when the air inside the housing expands due to heating for curing the resin composition, the air can escape from the case battery, and air leakage from between the resin composition and the block can be suppressed.

[0030] The present invention

[13] includes the method for manufacturing a case battery according to

[12] , wherein the sealing step further includes a step of closing the through-hole.

[0031] According to this method for manufacturing a case battery, the sealing step further includes a step of closing the through-hole, which can protect the stacked battery from contamination and prevent the material of the stacked battery from leaking to the outside. [Effects of the Invention]

[0032] The method for manufacturing a case battery of the present invention includes a filling step of filling a resin composition into a case, a placement step of placing a block so as to close the opening of the case, and a curing step of curing the resin composition while the block is placed downward in the direction of gravity relative to the case. Therefore, the resin composition can be cured in the opening of the case according to the shape of the block. Therefore, the shape of the peripheral edge of the case battery can be designed relatively flexibly. [Brief explanation of the drawings]

[0033] [Figure 1] 1A and 1B show an embodiment of a case battery manufactured by the manufacturing method of a case battery of the present invention, in which Fig. 1A shows a perspective view of the embodiment of the case battery, and Fig. 1B shows a cross-sectional view of the embodiment of the case battery. [Figure 2] 2A to 2C show one embodiment of the sealing step in the manufacturing method of the case battery of the present invention. Fig. 2A shows the filling step of filling the resin composition into the housing, Fig. 2B shows the arrangement step of arranging a block so as to close the opening of the housing, and Fig. 2C shows the curing step of curing the resin composition in a state where the block is arranged downward in the direction of gravity relative to the housing. [Figure 3] 3A to 3C show a sealing step in a first modified example of the manufacturing method of the case battery of the present invention, which is a first sealing step of sealing the first opening. Fig. 3A shows a first filling step of filling the first opening with a resin composition into the housing, Fig. 3B shows a first arranging step of arranging a block so as to block the first opening of the housing, and Fig. 3C shows a first curing step of curing the resin composition with the block arranged downward in the direction of gravity relative to the housing. [Figure 4]4D to 4F show a second sealing step of sealing the second opening, which is a step subsequent to the sealing step of the first modified example of the manufacturing method of the case battery shown in Fig. 3. Fig. 4D shows a second filling step of filling the second opening with a resin composition into the housing, Fig. 4E shows a second arranging step of arranging a block so as to block the second opening of the housing, and Fig. 4F shows a second curing step of curing the resin composition with the block arranged downward in the direction of gravity relative to the housing. [Figure 5] 5A to 5C show the sealing process in a second modified example of the manufacturing method for the case battery of the present invention. Fig. 5A shows the arrangement process in which a block is arranged to close the opening of the housing containing the stacked battery, Fig. 5B shows the filling process in which a resin composition is filled into the housing, and Fig. 5C shows the curing process in which the resin composition is cured with the block arranged downward in the direction of gravity relative to the housing. DETAILED DESCRIPTION OF THE INVENTION

[0034] 1. Case battery Referring to FIG. 1, one embodiment of a case battery 1 manufactured by the manufacturing method of a case battery of the present invention will be described.

[0035] As shown in Fig. 1, the case battery 1 includes a laminated battery 2, a housing 3, and a sealing body 4. The case battery 1 is an all-solid-state battery that uses a solid electrolyte as the electrolyte.

[0036] 1.1.Stacked battery The stacked battery 2 has a cell 20. In this embodiment, the stacked battery 2 includes the cell 20, a current collector 21 stacked on the cell 20, and a tab lead 22 connected to the current collector 21.

[0037] [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 that extend in a plane direction perpendicular to the thickness direction. The cell 20 has, for example, a substantially rectangular shape when viewed from the thickness direction. The plane direction includes a first direction and a second direction perpendicular to the first direction.

[0038] 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.

[0039] 1B, the cell 20 has a positive electrode layer 201, a negative electrode layer 202, and a solid electrolyte layer 203. Preferably, the cell 20 is made up of the positive electrode layer 201, the negative electrode layer 202, and the solid electrolyte layer 203. 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.

[0040] The positive electrode layer 201 is disposed apart from the negative electrode layer 202 in the thickness direction. 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. 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.

[0041] 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 necessarily have to contain a solid electrolyte. In other words, the positive electrode layer 201 may be made of only the positive electrode active material.

[0042] The positive electrode active material may be, for example, a lithium-containing oxide. Examples of the lithium-containing oxide include lithium-nickel composite oxide (LiNi X M 1-X O2), lithium cobalt oxide (LiCoO2), lithium nickel oxide (LiNiO2), lithium-nickel-cobalt-aluminum composite oxide (LiNi 0.8 Co 0.15 Al 0.05 O2, NCA-based layered oxides), lithium manganese oxide (spinel-type lithium manganese oxide (LiMn2O4)), and Li-excess composite oxides (Li2MnO3-LiMO2).

[0043] The positive electrode active material is not limited to lithium-containing oxides as long as it can insert and extract lithium ions. Examples of the positive electrode active material include olivine compounds (LiMPO4) and sulfur-containing compounds (Li2S). M represents a transition metal.

[0044] 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.

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

[0046] In addition, the surface of the positive electrode active material may be coated with a coating material from the viewpoint of improving rate characteristics. 12 , LiTaO3, Li4NbO3, LiAlO2, Li2ZrO3, Li2WO4, Li2TiO3, Li2B4O7, Li3PO4, Li2MoO4, LiBO2, alumina (Al2O3), and carbon (C).

[0047] The solid electrolyte exhibits lithium ion conductivity. Examples of the solid electrolyte include organic solid electrolytes and inorganic solid electrolytes.

[0048] Inorganic solid electrolytes include, for example, sulfides, oxides, nitrides, and hydrides.

[0049] The sulfide may, for example, contain LiS and another sulfide containing at least one element selected from the group consisting of Group 13, Group 14, and Group 15 elements of the periodic table. Examples of Group 13, Group 14, 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.

[0050] Specific examples of sulfides include Li2S-SiS2, Li2S-P2S5, Li2S-GeS2, Li2S-B2S3, Li2S-Ga2S3, Li2S-Al2S3, Li2S-GeS2-P2S5, Li2S-Al2S3-P2S5, Li2S-P2S3, Li2S-P2S3-P2S5, LiX-Li2S-P2S5, LiX-Li2S-SiS2, and LiX-Li2S-B2S3 (X: I, Br, or Cl).

[0051] The solid electrolyte is preferably an inorganic solid electrolyte. More preferably, a sulfide is used. The solid electrolyte can be used alone or in combination of two or more. The ratio of the positive electrode active material to the solid electrolyte is not limited.

[0052] The thickness of the positive electrode layer 201 is, for example, 50 μm or more, or preferably 100 μm or more, and for example, 500 μm or less, or preferably 300 μm or less.

[0053] The negative electrode layer 202 is disposed away from the positive electrode layer 201 in the thickness direction. 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. 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.

[0054] 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.

[0055] 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.

[0056] 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.

[0057] The negative electrode active material can be used alone or in combination of two or more kinds, for example, silicon oxide and a carbon material can be used in combination as the negative electrode active material.

[0058] Examples of the solid electrolyte contained in the negative electrode layer 202 include the solid electrolytes described above for the positive electrode layer 201. Preferably, the solid electrolyte contained in the negative electrode layer 202 is the same as the solid electrolyte contained in the positive electrode layer 201. The ratio of the negative electrode active material to the solid electrolyte is not limited.

[0059] The thickness of the negative electrode layer 202 is 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, or preferably 100 μm or more, and for example, 500 μm or less, or preferably 300 μm or less.

[0060] 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 only from a solid electrolyte.

[0061] The solid electrolyte may be, for example, the solid electrolyte described above in connection with the positive electrode layer 201. Preferably, the solid electrolyte is the same as the solid electrolyte contained in the positive electrode layer 201.

[0062] The thickness of 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.

[0063] The solid electrolyte layer 203 is preferably thinner than the positive electrode layer 201 and the negative electrode layer 202 .

[0064] [Current collector] The current collectors 21 are stacked on the cells 20. Specifically, as shown in FIG. 1B, 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. 1B, 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. 1B, the negative electrode current collector 21B is indicated by 211B and 212B.

[0065] In this embodiment, the cells 20 and the current collectors 21 are stacked in the following order from one side to the other in the thickness direction: first positive electrode current collector 211A, first cell 20A, first negative electrode current collector 211B, second cell 20B, second positive electrode current collector 212A, third cell 20C, and second negative electrode current collector 212B.

[0066] The current collector 21 includes a conductor 31 and an insulating member 32 .

[0067] The conductor 31 is made of, for example, metal. In this embodiment, the conductor 31 has a laminated portion 311 that contacts the cell 20 and a current collecting tab 312 that is connected to a tab lead 22 described later. Note that the conductor 31 does not necessarily have to have the current collecting tab 312.

[0068] The laminated portion 311 has a sheet shape that extends in a plane direction perpendicular to 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. In other words, the cells and current collectors are stacked in a parallel arrangement in a sheet-by-sheet stacking manner. The laminated portion 311 has a substantially rectangular shape when viewed in the thickness direction.

[0069] In this embodiment, the cells and current collectors are stacked in a parallel arrangement in a sheet-by-sheet stacking configuration. However, a series arrangement of the cells may also be used. A zigzag-like configuration may also be used instead of the sheet-by-sheet stacking configuration. Although not shown, a series arrangement of the sheet-by-sheet stacking configuration 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 with a series arrangement of the sheet-by-sheet stacking configuration is the stacked solid-state battery described in International Publication No. 2012 / 020700. Furthermore, although not shown, in a zigzag-like configuration, a long current collector 21 is folded zigzag, and the cells 20 are placed between the zigzag-like current collectors 21. A specific example of a zigzag-like configuration of the stacked battery is the all-solid-state battery described in Japanese Patent Application Laid-Open No. 2020-113434.

[0070] The current collecting tab 312 is disposed on the peripheral edge of the laminated portion 311. For example, the current collecting tab 312 is disposed on the peripheral edge of one side of the laminated portion 311 in the second direction. The current collecting tab 312 protrudes from the peripheral edge of the laminated portion 311.

[0071] 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. 1A, 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.

[0072] 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 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 laminate portion 311.

[0073] As described above, the length of current collecting tab 312 in the first direction is set appropriately within a range in which positive electrode current collecting tab 312A and negative electrode current collecting tab 312B do not come into contact with each other. The length of current collecting tab 312 in the second direction (length in the protruding direction) is not particularly limited, and it is sufficient that the length is long enough to connect to tab lead 22, which will be described later.

[0074] 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.

[0075] 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.

[0076] The insulating member 32 is laminated on one surface of the conductor 31 in the thickness direction. 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 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 is not disposed on the current collecting tab 312 of the conductor 31.

[0077] 1B , 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. 1B , 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 positive electrode current collector 21A and 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.

[0078] The thickness of the insulating member 32 is thinner than the thickness of the cells 20. When the current collector 21 does not have an adhesive layer described later, the thickness of the insulating member 32 may be the same as the thickness of the cells 20. The thickness of the insulating member 32 is, for example, 50 μm or more, or preferably 75 μm or more, and for example, 500 μm or less, or preferably 400 μm or less.

[0079] Examples of materials for the insulating member 32 include polyethylene terephthalate and polyimide.

[0080] The current collector 21 may further have an adhesive layer disposed between the current collector 21 and the insulating member 32 at the periphery of the conductor 31 .

[0081] 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 33 is, for example, 30 μm or more, or preferably 50 μm or more, and for example, 300 μm or less, or preferably 200 μm or less.

[0082] 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.

[0083] [Tab lead] The tab leads 22 are electrically connected to the current collectors 21, and electrically connect the stacked battery 2 to the outside.

[0084] 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.

[0085] Specifically, the tab lead 22 is electrically connected to the current collecting tab 312. When the conductor 31 of the current collector 21 does not include the current collecting tab 312, the tab lead 22 may be directly connected to the laminated portion 311. In this embodiment, as shown in FIG. 1B , the tab lead 22 is electrically connected to the current collecting tab 312 and 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 lead 22A 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 lead 22B is electrically connected to the negative electrode current collecting tab 312B.

[0086] 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. Alternatively, the tab lead 22 may be formed of the same member as the laminated portion 311 and formed by extending a portion of the edge of the laminated portion 311.

[0087] 1B, the tab lead 22 extends in the same direction as the protruding direction of the current collecting tab 312 (the second direction), and protrudes from the opening of the housing 3 in which the sealing body 4 is disposed.

[0088] In the battery stack 2, the tab leads 22 protrude from the openings 30 of the housing 3, so that the battery stack 2 can be easily electrically connected to the outside via the tab leads 22.

[0089] 1A, 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 first direction. In addition, the positive electrode tab lead 22A does not overlap with the negative electrode tab lead 22B in the thickness direction.

[0090] The material of the tab lead 22 is not particularly limited as long as it is usable as a lead wire of 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.

[0091] The tab lead 22 has a thickness of, for example, 5 μm or more, or preferably 10 μm or more, and for example, 500 μm or less, or preferably 200 μm or less.

[0092] The length of tab lead 22 in the protruding direction is not particularly limited as long as it has a length sufficient to protrude from the opening of housing 3 in which sealing body 4 is disposed.

[0093] The connection portion between the tab lead 22 and the current collector 21 may be disposed on the other side of the sealing body 4 in the second direction, or may be disposed on one side of the sealing body 4 in the second direction (protruding from the opening), or may be embedded in the sealing body 4. In this embodiment, the connection portion between the tab lead 22 and the current collector 21 is embedded in the sealing body 4.

[0094] If the connection portion between tab lead 22 and current collector 21 is embedded in sealing body 4, the positions of current collector 21 and tab lead 22 are fixed, thereby preventing the connection portion from being broken due to vibration or the like.

[0095] 1.2.Housing The housing 3 houses the stacked battery 2. The housing 3 protects the stacked battery 2 from contamination.

[0096] The shape of the housing 3 is not particularly limited as long as it can accommodate the stacked battery 2. The shape of the housing 3 is, for example, a rectangular tube. The outer surfaces of the housing 3 may be curved inward. Specifically, each of the outer surfaces of the housing 3 may be concave.

[0097] The housing 3 is made of, for example, a metal. Examples of metals include aluminum and stainless steel. The housing 3 may be a molded body made by processing a plate material (excluding foil) of the above metals, a bonded body made by bonding plate materials, or a composite bonded body made by bonding a molded body and a plate material.

[0098] The housing 3 has a thickness that prevents deformation during normal use of the case battery 1. The thickness of the housing 3 is, for example, 0.1 mm or more, preferably 0.2 mm or more, and for example, 2 mm or less, preferably 1 mm or less.

[0099] Before accommodating the battery stack 2, the internal dimensions of the casing 3 are not particularly limited as long as they can accommodate the battery stack 2. The internal thickness of the casing 3 is, for example, equal to or greater than the thickness of the battery stack 2. Preferably, it is approximately the same as the thickness of the battery stack 2. The internal length of the casing 3 in the first direction is not particularly limited as long as it is equal to or greater than the length of the battery stack 2 in the first direction. The internal length of the casing 3 in the second direction is not particularly limited as long as it is equal to or greater than the length of the battery stack 2 in the second direction. If the external surface of the casing 3 is concave, the minimum internal length of the casing 3 in the thickness direction may be less than the thickness of the battery stack 2. If the external surface of the casing 3 is concave, the minimum internal length of the casing 3 in the first direction may be less than the length of the battery stack 2 in the first direction.

[0100] At least a portion of the inner circumferential surface of the casing 3 preferably contacts at least a portion of the outer circumferential surface of the stacked battery 2. Alternatively, the entire inner surface of the casing 3 may contact the entire outer circumferential surface of the stacked battery 2. In other words, the case battery 1 preferably has no gap at least partially between the inner circumferential surface of the casing 3 and the outer circumferential surface of the stacked battery 2. Specifically, the stacked battery 2 is held within the casing 3 by the inner circumferential surface of the casing 3 contacting the outer circumferential surface of the stacked battery 2. Note that the inner circumferential surface of the casing 3 that is not in contact with the outer circumferential surface of the stacked battery 2 faces the outer circumferential surface of the stacked battery 2 with a gap between them.

[0101] The shortest distance of the gap between the inner surface of the casing 3 and the outer surface of the stacked battery 2 is, for example, less than 0.5 mm, preferably 0.3 mm or less, more preferably 0.1 mm or less, even more preferably 0.05 mm or less, particularly preferably 0.01 mm or less, and most preferably 0 mm.

[0102] In this embodiment, the inner surface of the casing 3 contacts the outer surface of the stacked battery 2. Preferably, the entire inner surface of the casing 3 (both inner circumferential surfaces in the thickness direction and both inner circumferential surfaces in the first direction) contacts the entire outer surface of the stacked battery 2 (both outer circumferential surfaces in the thickness direction and both outer circumferential surfaces in the first direction). In other words, there is almost no gap between the inner surface of the casing 3 and the outer surface of the stacked battery 2. Furthermore, the other side of the inner circumferential surface of the casing 3 in the second direction does not contact the other side of the stacked battery 2 in the second direction, but faces each other with a gap therebetween.

[0103] The housing 3 has an opening 30 on at least a portion of its peripheral edge. In the peripheral edge of the housing 3 having the opening 30, the entire peripheral edge surface may be an opening, or only a portion of the peripheral edge surface may be an opening. In this embodiment, the housing 3 has the opening 30 on only a portion of the peripheral edge. Specifically, the housing 3 has the opening 30 on the peripheral edge on one side in the second direction, and the entire peripheral edge surface on one side in the second direction is an opening 30.

[0104] If the housing 3 has the opening 30 only in a part of its peripheral edge, the case battery can be easily manufactured, and the risk of exposing the stacked battery to external contamination can be reduced.

[0105] 1.3. Sealing body The sealing body 4 seals the opening 30 of the housing 3 .

[0106] The sealing body 4 is a cured product (C stage) of the resin composition 40. The resin composition 40 is in a state (A stage or B stage) before curing.

[0107] The resin composition 40 contains a resin. Examples of the resin include a thermosetting resin and a photocurable resin. From the viewpoint of being able to sufficiently cure the resin composition 40 inside the housing 3, a thermosetting resin is preferably used. In other words, the resin composition 40 is preferably a thermosetting resin composition.

[0108] If the resin composition 40 is a thermosetting resin composition, the opening 30 of the housing 3 can be sealed in a simple manufacturing process.

[0109] Examples of thermosetting resins include epoxy resins, silicone resins, urethane resins, polyimide resins, urea resins, melamine resins, and unsaturated polyester resins. Epoxy resins are preferred. The thermosetting resins can be used alone or in combination of two or more.

[0110] Examples of epoxy resins include bisphenol A type epoxy resins, bisphenol F type epoxy resins, modified bisphenol A type epoxy resins, modified bisphenol F type epoxy resins, biphenyl type epoxy resins, phenol novolac type epoxy resins, cresol novolac type epoxy resins, trishydroxyphenylmethane type epoxy resins, tetraphenylolethane type epoxy resins, and dicyclopentadiene type epoxy resins.

[0111] When an epoxy resin is used, the thermosetting resin preferably contains a phenolic resin as a curing agent for the epoxy resin, such as a novolac-type phenolic resin or a triphenylmethane-type phenolic resin.

[0112] The resin composition may contain other components, such as a thermoplastic resin, a rheology control agent, an internal mold release agent, a pigment, and a silane coupling agent.

[0113] The resin composition 40 is, for example, liquid.

[0114] The viscosity of the resin composition 40 at 25°C is, for example, 10 Pa·s or more, preferably 30 Pa·s or more, more preferably 50 Pa·s or more, and for example, 800 Pa·s or less, preferably 600 Pa·s or less, more preferably 400 Pa·s or less.

[0115] If the viscosity of the resin composition 40 at 25°C is below the above upper limit, the resin composition 40 can flexibly deform to fit the shape of the block 5 described below, and therefore the shape of the peripheral end of the case battery 1 can be designed relatively flexibly to suit the application.

[0116] The viscosity of the resin composition 40 at 25° C. is measured by a rotational viscometer.

[0117] When the resin composition 40 is a thermosetting composition, the curing temperature is, for example, 50°C or higher, preferably 60°C or higher, more preferably 70°C or higher, and for example, 150°C or lower.

[0118] The shape and dimensions of the sealing body 4 are not particularly limited as long as it can seal the opening of the housing 3 .

[0119] Specifically, one end face (one side in the second direction) of the sealing body 4 is formed to fit the shape of the block 5 described below. The peripheral edge of the opening 30 of the housing 3 and one end face (one side in the second direction) of the sealing body 4 are preferably flush with each other.

[0120] If the peripheral edge of the opening 30 of the housing 3 and one end face (one face in the second direction) of the sealing body 4 are flush with each other, it is possible to prevent the sealing body 4 from coming off the opening 30 of the housing 3 due to an external impact, etc. Furthermore, the case battery 1 has an excellent appearance.

[0121] The other end surface (the other side in the second direction) of the sealing body 4 may be in contact with one side in the second direction of the battery stack 2, or may face the one side in the second direction of the battery stack 2 at a distance in the second direction. In this case, the one side in the second direction of the battery stack 2 refers to the one side in the second direction excluding the protruding portions (specifically, the tab leads 22 and the current collecting tabs 312).

[0122] Furthermore, the peripheral side surface of the sealing body 4 contacts the inner peripheral surface of the housing 3. Specifically, the entire peripheral side surface of the sealing body 4 contacts the entire inner peripheral surface of the housing 3.

[0123] The length of the sealing body 4 in the second direction is not particularly limited, and is equal to or less than the length in the second direction inside the housing 3. Preferably, the length is equal to or less than the distance from the peripheral edge of the opening 30 of the housing 3 to one side of the stacked battery 2 in the second direction.

[0124] 2. Manufacturing method of case battery An embodiment of a method for manufacturing a case battery of the present invention will be described with reference to Fig. 2. The method for manufacturing the case battery 1 described above is one embodiment of the method for manufacturing a case battery.

[0125] The manufacturing method of the case battery includes a sealing step of sealing the opening 30 of the housing 3 with the sealing body 4. Specifically, in the manufacturing method of the case battery, the housing 3 containing the stacked battery 2 is prepared, and the opening 30 of the housing 3 is sealed with the sealing body 4.

[0126] 2A to 2C, the sealing step in the manufacturing method of the case battery includes a filling step of filling the resin composition 40 into the housing 3, an arrangement step of arranging the block 5 so as to close the opening 30 of the housing 3, and a curing step of curing the resin composition 40 in a state in which the block 5 is arranged downward in the direction of gravity relative to the housing 3. In this embodiment, the sealing step includes the filling step, the arrangement step, and the curing step in that order.

[0127] (filling process) As shown in FIG. 2A, in the filling step, a resin composition 40 is filled into the housing 3 housing the stacked battery 2.

[0128] The filling method is not particularly limited, but for example, the resin composition 40 can be filled by injecting it from the opening 30 of the housing 3 that houses the stacked battery 2.

[0129] In this embodiment, in order to prevent the resin composition 40 from spilling, the housing 3 is positioned so that one side in the second direction faces upward in the direction of gravity and the other side in the second direction faces downward in the direction of gravity, that is, so that the opening 30 of the housing 3 opens upward in the direction of gravity, and then the resin composition 40 is injected.

[0130] Furthermore, in this embodiment, since there is no gap between the inner peripheral surface of the casing 3 and the outer peripheral surface of the stacked battery 2, the injected resin composition 40 is filled onto the upper surface of the stacked battery 2 in the direction of gravity (the surface facing the opening 30 of the casing 3). In other words, the resin composition 40 comes into contact with the upper surface of the stacked battery 2 in the direction of gravity. Note that, if there is a gap between the inner peripheral surface of the casing 3 and the outer peripheral surface of the stacked battery 2, the injected resin composition 40 may be filled onto the lower surface of the interior of the casing 3 in the direction of gravity (the surface on the opposite side of the opening 30 of the casing 3 in the direction of gravity), in which case the resin composition 40 comes into contact with the lower surface of the interior of the casing 3 in the direction of gravity.

[0131] The filling amount V of the resin composition 40 is, relative to the difference (V0-V1) between the volume V0 inside the casing 3 and the volume V1 of the stacked battery 2, i.e., the volume of the gap inside the casing 3, is, for example, 100% by volume or less, preferably 80% by volume or less, more preferably 60% by volume or less, even more preferably 50% by volume or less, particularly preferably 40% by volume or less, and most preferably 30% by volume or less, or, for example, 10% by volume or more.

[0132] If the filling amount V of the resin composition 40 is 50 volume % or less of the difference (V0-V1) between the internal volume V0 of the casing 3 and the volume V1 of the stacked battery 2, the weight of the case battery 1 can be reduced and costs can also be reduced.

[0133] In addition, the filling amount V of the resin composition 40 indicates the total filling amount when the resin composition 40 is filled multiple times.

[0134] In the filling step, the housing 3 may be heated before filling with the resin composition 40. The heating temperature is, for example, 150°C or less, or preferably 120°C or less, and for example, 40°C or more, or preferably 50°C or more.

[0135] In the filling process, by heating the housing 3 within the above range of the resin composition 40, excessive expansion of the air inside the housing 3 due to heating to harden the resin composition 40 can be prevented, and air leakage from between the resin composition 40 and the block 5 can be prevented.

[0136] (Placement process) As shown in FIG. 2B, in the placement step, the block 5 is placed so as to close the opening 30 of the housing 3.

[0137] In this embodiment, in order to prevent the filled resin composition 40 from spilling, the opening 30 of the housing 3 is arranged so as to open upward in the direction of gravity, and the block 5 is arranged so as to close the opening 30 of the housing 3. In this case, the block 5 is arranged upward in the direction of gravity with respect to the housing 3.

[0138] Since the opening 30 of the housing 3 is closed by the block 5, leakage of the resin composition 40 can be prevented in the curing step described below.

[0139] In the disposing step, the block 5 may or may not be in contact with the resin composition 40. Preferably, the block 5 is not in contact with the resin composition 40.

[0140] The shape of the block 5 is not particularly limited as long as it can close the opening 30 of the housing 3, and an appropriate shape is selected depending on the desired shape of the peripheral edge of the case battery 1. Examples of the shape of the block 5 include a prismatic shape and a cylindrical shape. Alternatively, the block 5 may have a shape that is a partial prismatic shape or a cylindrical shape. In this embodiment, the block 5 has a prismatic shape (specifically, a quadrangular prism shape).

[0141] Examples of materials for the block 5 include thermosetting resins, thermoplastic resins, and metals. The block 5 is preferably formed from an elastic material. That is, the material for the block 5 is preferably a thermoplastic resin. Examples of thermoplastic resins include natural rubber, butyl rubber, isoprene rubber, chloroprene rubber, ethylene-vinyl acetate copolymer, ethylene-acrylic acid copolymer, ethylene-acrylic acid ester copolymer, polybutadiene resin, polycarbonate resin, thermoplastic polyimide resin, polyamide resin, phenoxy resin, acrylic resin, saturated polyester resin, polyamide-imide resin, fluororesin, and styrene-isobutylene-styrene block copolymer. Fluororesin is preferred. Specifically, the material for the block 5 is polytetrafluoroethylene.

[0142] If the block 5 is made of an elastic material, the block 5 can be deformed to fit the shape of the opening 30 of the housing 3, which further reduces leakage of the resin composition 40 in the curing step described below. In particular, even if the viscosity of the resin composition 40 is low, leakage of the resin composition 40 can be reduced.

[0143] Furthermore, the block 5 preferably has releasability relative to the encapsulant 4. The block 5 may have releasability relative to the encapsulant 4 due to its material, or the surface of the block 5 that comes into contact with the encapsulant 4 (resin composition 40) may be surface-treated so as to have releasability.

[0144] If the block 5 has releasability relative to the sealing body 4, the block 5 can be easily peeled off after the resin composition 40 has hardened. Furthermore, the case battery 1 has an excellent appearance.

[0145] The block 5 is disposed so as to close the opening 30 of the housing 3. Specifically, the block 5 contacts the peripheral edge of the opening 30 of the housing 3.

[0146] Only one block 5 may be disposed, or multiple blocks may be disposed depending on the desired shape of the peripheral edge of the case battery 1. If an excessive number of blocks 5 are disposed, there is a risk that the resin composition 40 will leak between adjacent blocks 5 during the curing step described below. Therefore, the number of blocks 5 is preferably four or less. More preferably, it is one or two.

[0147] When multiple blocks 5 are arranged, adjacent blocks 5 are arranged so that the resin composition 40 does not leak in the curing step described below, and at least a portion of the blocks 5 is in contact with each other. The blocks 5 may be arranged so that a tab lead 22 or the like is sandwiched between adjacent blocks 5. In this embodiment, the opening 30 of the housing 3 is sealed with the tab lead 22 protruding from the opening 30, so the two blocks 5 are arranged so as to sandwich the tab lead 22 and close the opening 30 of the housing 3.

[0148] In the arrangement step, by arranging multiple blocks 5 so as to sandwich the tab leads 22 and close the opening 30 of the housing 3, it is possible to easily seal the opening 30 of the housing 3 while allowing the tab leads 22 to protrude from the housing 3. Furthermore, since there is no need to seal the tab leads 22 separately, the process can be simplified. Furthermore, in the curing step described below, when the resin composition 40 is cured, it is possible to prevent the tab leads 22 from being pulled and breaking.

[0149] The dimensions of the block 5 are not particularly limited as long as they are large enough to close the opening 30 of the housing 3 .

[0150] (hardening process) As shown in FIG. 2C, in the curing step, the resin composition 40 is cured in a state in which the block 5 is placed on the lower side of the housing 3 in the direction of gravity.

[0151] Specifically, in the placement step, the block 5 is rotated 180 degrees from a state in which it is placed on the upper side of the housing 3 in the direction of gravity, while the opening 30 of the housing 3 is still covered by the block 5. As a result, the block 5 is placed on the lower side of the housing 3 in the direction of gravity, and the resin composition 40 flows downward in the direction of gravity. In this state, the resin composition 40 is cured. Note that after the 180-degree rotation, one side in the second direction becomes the lower side in the direction of gravity, and the other side in the second direction becomes the upper side in the direction of gravity.

[0152] At this time, the resin composition 40 comes into contact with the upper surface of the block 5 in the gravity direction (the surface that comes into contact with the peripheral edge of the opening 30 of the housing 3). The resin composition 40 also comes into contact with the entire inner circumferential surface of the opening 30 of the housing 3.

[0153] The method for curing the resin composition 40 is appropriately selected depending on the material of the resin composition 40. If the resin composition 40 is a thermosetting resin composition, it is cured by heating. If the resin composition 40 is a photocurable resin composition, it is cured by irradiating it with light.

[0154] The resin composition 40 is preferably a thermosetting resin composition and is cured by heating. The heating temperature is not particularly limited as long as it is equal to or higher than the curing temperature of the thermosetting resin composition, and is, for example, 50°C or higher, preferably 60°C or higher, more preferably 70°C or higher, and for example, 150°C or lower. The heating time is also not particularly limited as long as it is long enough to cure the thermosetting resin composition, and is, for example, 10 minutes or longer, preferably 30 minutes or longer, and for example, 6 hours or shorter, preferably 3 hours or shorter.

[0155] As a result, the opening 30 of the housing 3 can be sealed with the sealing body 4.

[0156] After sealing, the block 5 is removed to produce the case battery 1.

[0157] (Action and effect) In the manufacturing method of the case battery of the present invention, the sealing step includes a filling step of filling the resin composition 40 into the housing 3, an arrangement step of arranging the block 5 so as to close the opening 30 of the housing 3, and a curing step of curing the resin composition 40 in a state in which the block 5 is arranged downward in the direction of gravity relative to the housing 3. Therefore, the resin composition 40 can be cured in the opening 30 of the housing 3 in accordance with the shape of the block 5. As a result, the shape of the peripheral edge of the case battery 1 can be designed relatively flexibly.

[0158] 3. Variations In the modified example, the same components and steps as those in the above-described embodiment of the case battery and the embodiment of the manufacturing method for the case battery are designated by the same reference numerals, and detailed descriptions thereof will be omitted. Furthermore, unless otherwise specified, the modified example can achieve the same effects as those in the embodiment of the case battery and the embodiment of the manufacturing method for the case battery. Furthermore, the modified example can be appropriately combined with the embodiment of the case battery or the embodiment of the manufacturing method for the case battery.

[0159] 3.1. First variant of the case battery In the embodiment of the case battery 1 described above, the stacked battery 2 is directly housed in the housing 3, but the present invention is not limited to this.

[0160] Specifically, although not shown, the battery stack 2 may be a laminated battery stack housed in a laminate film in the case battery 1. The laminated battery stack includes the battery stack 2 and a laminate film.

[0161] There are no particular limitations on the laminate film, as long as it is one that is normally used for laminating the stacked battery 2. An example of the laminate film is a metal laminate film in which resin films are laminated on both sides of a metal foil.

[0162] If the battery stack 2 is provided with a laminate film, the battery stack 2 can be further protected from external contamination.

[0163] The thickness (total thickness) of the laminate film 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.

[0164] When the stacked battery 2 includes a laminate film, the tab leads 22 protrude from part of the peripheral edge of the laminate film.

[0165] When the stacked battery 2 is a laminated stacked battery, the laminated stacked battery is housed in the housing 3, and the opening 30 of the housing 3 is sealed using the same sealing process as in the manufacturing method of the case battery described above. In this way, a case battery including a laminated stacked battery is manufactured.

[0166] 3.2. Second variant of the case battery In the embodiment of the case battery 1 described above, the housing 3 has the opening 30 only in a part of the peripheral edge, but the present invention is not limited to this.

[0167] Specifically, although not shown, in the case battery 1, the opening 30 of the housing 3 may have a first opening and a second opening that are spaced apart from each other. When the housing 3 has the first opening and the second opening, the first opening and the second opening are arranged on one side and the other side in the same direction. For example, when the first opening is arranged on one side in the second direction, the second opening is arranged on the other side in the second direction.

[0168] In this case, tab lead 22 may protrude from only one of the first opening and the second opening, or may protrude from both the first opening and the second opening.

[0169] In other words, if the opening 30 of the housing 3 has a first opening and a second opening that are spaced apart from each other, the connection position between the stacked battery 2 and the outside can be designed relatively flexibly to suit the application of the case battery 1.

[0170] The manufacturing method of the second modified case battery will be described later.

[0171] 3.3. First variant of the manufacturing method for the case battery In one embodiment of the manufacturing method of the case battery described above, the housing 3 has an opening 30 only in a part of the peripheral edge, and only one opening 30 is sealed, but the present invention is not limited to this.

[0172] The first modified example of the manufacturing method for the case battery specifically corresponds to the second modified example of the manufacturing method for the case battery described above.

[0173] The first variant of the manufacturing method for the case battery includes a first sealing step of sealing the first opening 301, as shown in Figures 3A to 3C, and a second sealing step of sealing the second opening 302, as shown in Figures 4D to 4F.

[0174] The first sealing process includes a first filling process of filling the housing 3 with the resin composition 40 through the first opening 301, as shown in FIG. 3A; a first placement process of placing the block 5 so as to block the first opening 301 of the housing 3, as shown in FIG. 3B; and a first curing process of curing the resin composition 40 while the block 5 is placed downward in the direction of gravity relative to the housing 3, as shown in FIG. 3C.

[0175] The first sealing step is the same as the sealing step of sealing the opening 30 in the embodiment of the manufacturing method of the case battery described above.

[0176] The first sealing step does not necessarily include the first filling step, the first arranging step, and the first curing step in this order. Specifically, the first sealing step may include the first arranging step, the first filling step, and the first curing step in this order.

[0177] When the first sealing step includes the first disposing step, the first filling step, and the first curing step in this order, first, although not shown, the block 5 is disposed so as to block the first opening 301 of the housing 3. Then, with the block 5 disposed on the lower side of the housing 3 in the direction of gravity, the resin composition 40 is filled into the housing 3 through the second opening 302. Then, the resin composition 40 flows downward in the direction of gravity and is disposed so as to block the first opening 301, and then the resin composition 40 is cured.

[0178] Furthermore, although not shown, a separate step of forming a through hole in the sealing body 4 (first sealing body 41) that seals the first opening 301 may be included. As a method of forming a through hole in the first sealing body, for example, a wire or a fishing line is placed in the first opening 301 before the first sealing step, and then the first sealing step is performed. Then, after the first sealing step, the placed wire or fishing line is removed, thereby forming a through hole in the first sealing body 41. Furthermore, after the first sealing step, a through hole can also be formed in the first sealing body 41 using a needle or the like. In other words, the first sealing body 41 has a through hole.

[0179] The through holes allow air to escape from the case battery 1 when the resin composition 40 is heated to harden it in the second hardening step, causing the air inside the housing 3 to expand. As a result, air leakage between the resin composition 40 and the block 5 can be suppressed.

[0180] The through holes are blocked after or during the second curing step described below. That is, the sealing step further includes a step of blocking the through holes. When the through holes are blocked after the second curing step, the resin composition 40 is injected into the through holes after the second curing step and heated. When the through holes are blocked during the second curing step, the resin composition 40 is injected into the through holes while being heated to near the curing temperature of the thermosetting resin composition and cured. The heating to near the curing temperature of the thermosetting resin composition is appropriately adjusted within a temperature range in which the thermosetting resin composition does not completely cure.

[0181] Next, the second sealing process includes a second filling process of filling the resin composition 40 into the housing 3 through the second opening 302, a second placement process of placing the block 5 so as to block the second opening 302 of the housing 3, and a second curing process of curing the resin composition 40 while the block 5 is placed downward in the direction of gravity relative to the housing 3.

[0182] The second sealing step shown in FIGS. 4D to 4F is the same as the sealing step of sealing the opening 30 in the embodiment of the manufacturing method of the case battery described above.

[0183] The tab leads 22 of the battery stack 2 do not protrude from the second opening 302. Therefore, only one block is required to cover the second opening 302, as shown in FIG. 4E.

[0184] 3.4. Second variant of the manufacturing method for the case battery The second modified example of the manufacturing method of the case battery is a manufacturing method of the case battery 1 in which the housing 3 has a through-hole 6.

[0185] In the second modified example of the manufacturing method of the case battery, the housing 3 has a through hole 6. Specifically, the housing 3 has the through hole 6 in a part of the peripheral side surface excluding the opening 30. Preferably, the through hole 6 is provided in the peripheral side surface near the opening 30. Note that the vicinity of the opening 30 refers to the area between the opening of the housing 3 and the peripheral end of the stacked battery 2 in the direction of gravity (second direction).

[0186] As shown in Figures 5A to 5C, in the second variant of the manufacturing method for a case battery, the sealing process in the second variant of the manufacturing method for a case battery includes an arrangement process of arranging a block 5 so as to block an opening 30 of a housing 3 containing a stacked battery 2, a filling process of filling a resin composition 40 into the housing 3, and a curing process of curing the resin composition 40 while the block 5 is arranged downward in the direction of gravity relative to the housing 3.

[0187] As shown in Fig. 5A, block 5 is placed so as to block opening 30 of housing 3. Then, as shown in Fig. 5B, resin composition 40 is filled into housing 3 in a state in which block 5 is placed downward in the direction of gravity relative to housing 3. Next, as shown in Fig. 5C, after resin composition 40 is placed so as to block opening 30, resin composition 40 is cured.

[0188] More specifically, in this modification, in the filling step, the resin composition 40 is filled through the through-hole 6. At this time, the filling amount V of the resin composition 40 is appropriately adjusted within a range that does not fill the through-hole 6 when the block 5 is placed on the lower side of the housing 3 in the direction of gravity.

[0189] Furthermore, the through-hole 6 is blocked after or during the curing process. That is, the sealing process further includes a step of blocking the through-hole. When the through-hole is blocked after the curing process, the resin composition 40 is injected into the through-hole after the curing process and heated. When the through-hole is blocked during the curing process, the case battery 1 is heated to near the curing temperature of the thermosetting resin composition, tilted in the direction of the through-hole 6 of the housing 3, and the thermosetting resin composition is cured with the through-hole 6 blocked. Note that the heating to near the curing temperature of the thermosetting resin composition is appropriately adjusted within a temperature range in which the thermosetting resin composition does not completely cure. [Explanation of symbols]

[0190] 1 case battery 2. Stacked battery 20 cells 201 Positive electrode layer 202 negative electrode layer 203 Solid electrolyte layer 3. Housing 4 Encapsulation body 40 Resin composition 5 blocks

Claims

1. A method for manufacturing a case battery, the method comprising: manufacturing 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 case that houses the laminated battery and has an opening in at least a part of a peripheral edge; and a seal that seals the opening of the case, The manufacturing method of the case battery includes a sealing step of sealing the opening of the housing with the sealing body, The sealing step includes: a filling step of filling the housing with a resin composition; a placement step of placing a block so as to close the opening of the housing; a curing step of curing the resin composition in a state in which the block is disposed on a lower side in a gravity direction relative to the housing; A method for manufacturing a case battery comprising:

2. The method for manufacturing a case battery according to claim 1 , wherein the housing has the opening only in a portion of the peripheral edge.

3. The method for manufacturing a case battery according to claim 1 , wherein the opening of the housing has a first opening and a second opening that are spaced apart from each other.

4. The method for manufacturing a case battery according to any one of claims 1 to 3, wherein a peripheral edge of the opening of the housing and one end face of the sealing body are flush with each other.

5. The method for manufacturing a case battery according to any one of claims 1 to 3, wherein the viscosity of the resin composition at 25°C is 400 Pa·s or less.

6. The method for manufacturing a case battery according to any one of claims 1 to 3, wherein the resin composition is a thermosetting resin composition.

7. the block is formed from an elastic material; The method for manufacturing a battery according to any one of claims 1 to 3, wherein the block has releasability relative to the sealing body.

8. the stacked battery further includes a current collector stacked on the cell and a tab lead connected to the current collector; the stacked battery is housed in the housing such that the tab leads protrude from the opening of the housing; The method for manufacturing a case battery according to any one of claims 1 to 3, wherein in the arranging step, a plurality of the blocks are arranged so as to sandwich the tab lead and close the opening of the housing.

9. The method for manufacturing a case battery according to claim 8 , wherein a connection portion between the current collector and the tab lead is embedded in the sealing body.

10. In the filling step, the filling amount V of the resin composition is 50% by volume or less relative to the difference (V0-V1) between the volume V0 inside the casing and the volume V1 of the laminated battery. The manufacturing method of the case battery according to any one of claims 1 to 3.

11. The method for manufacturing a case battery according to any one of claims 1 to 3, wherein the case is heated to 50°C or higher and 150°C or lower in the filling step.

12. The method for manufacturing a case battery according to any one of claims 1 to 3, wherein at least one selected from the group consisting of the casing and the sealing body is provided with a through hole.

13. The method for manufacturing a case battery according to claim 12 , wherein the sealing step further comprises a step of closing the through-hole.

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