Battery, all-solid battery, battery module, and battery manufacturing method

Abstract

Provided are a battery, a full-solid-state battery, a battery module, and a battery manufacturing method that reduce the number of components. A full-solid-state battery (1) includes: an electrode laminate (2) formed in a cuboid shape; an exterior body (3) of a laminate film having a folding portion (30) on a long side of the electrode laminate (2) and accommodating the electrode laminate (2); and a holding member (100) disposed on a short side of the electrode laminate (2) and connected to the folding portion (30).

Description

Technical Field

[0001] This invention relates to batteries, all-solid-state batteries, battery modules, and battery manufacturing methods. Background Technology

[0002] In recent years, research and development related to batteries that contribute to energy efficiency have been carried out in order to ensure access to more people's access to reliable, sustainable and advanced energy.

[0003] Furthermore, due to depressurization during manufacturing processes and gas generation during charging and discharging, the internal pressure of the battery sometimes changes. These internal pressure changes can cause deformation of the laminated outer casing, such as expansion or contraction. For example, when a battery is used continuously for an extended period beyond its warranty period, the deformation of the outer casing may increase, leading to cracking of the welded portion due to stress during deformation. Therefore, the proposal suggests incorporating a protective member within the outer casing to limit deformation of the outer casing caused by internal pressure changes and prevent cracking of the welded portion.

[0004] Patent Document 1 discloses a secondary battery (laminated battery) in which a protective member is housed within an outer casing. This battery includes: an electrode body having a terminal connection portion; an outer casing having a fusion-bonded portion; electrode terminals; a main retainer; side retainers; and resin. The main retainer is disposed between the electrode body and the outer casing, clamping the electrode terminals in the lamination direction. The side retainers are mounted on both ends of the side of the electrode body having the terminal connection portion. The side retainers have a structure that engages with the main retainer.

[0005] Prior art literature

[0006] Patent documents

[0007] Patent Document 1: Japanese Patent Application Publication No. 2022-14715 Summary of the Invention

[0008] The problem that the invention aims to solve

[0009] In the structure of Patent Document 1, the side retainer installed on the electrode body is fitted and fixed with the main retainer, which serves as a protective member, thus allowing for improvement in reducing the number of parts.

[0010] This application aims to solve the aforementioned problems by reducing the number of components. Furthermore, it contributes to energy efficiency.

[0011] Solution for solving the problem

[0012] As a solution to the above-mentioned problems, the present invention has the following structure.

[0013] (1) The battery according to the present invention (e.g., the all-solid-state battery 1 in the embodiment) comprises: an electrode stack (e.g., the electrode stack 2 in the embodiment), which is formed in the shape of a cuboid; an outer casing of a laminate (e.g., the outer casing 3 in the embodiment), which has a folded portion (e.g., the folded portion 30 in the embodiment) on the long side of the electrode stack and houses the electrode stack; and a retainer (e.g., the retainer 100 in the embodiment), which is disposed on the short side of the electrode stack and connected to the folded portion.

[0014] According to this structure, by connecting the retainer to the folding portion of the outer body, other components (such as the side retainer disclosed in Patent Document 1) are not required for connecting the outer body to the retainer. Therefore, the number of parts can be reduced. Moreover, it also contributes to energy efficiency.

[0015] (2) In the battery described in (1) above, an opening for receiving the end of the folded portion may also be formed in the retainer (for example, opening 101 in the embodiment).

[0016] According to this structure, the outer casing and the retainer can be connected by accommodating the end of the folded portion of the outer casing into the opening of the retainer. Therefore, compared with the connection by a retaining mechanism such as a chuck mechanism, it helps to save space. As a result, the battery can be miniaturized, and the volumetric energy density efficiency can be improved.

[0017] (3) In the battery described in (2) above, the retaining member may also include a first retaining member (e.g., the first retaining member 110 in the embodiment) and a second retaining member (e.g., the second retaining member 120 in the embodiment) that are arranged overlapping each other in the thickness direction of the electrode stack, and the opening is formed in either the first retaining member or the second retaining member.

[0018] According to this structure, by overlapping each other in the thickness direction of the electrode laminate with the first and second retaining members, the outer casing can be more effectively protected from external factors. Furthermore, the outer casing can be connected to the retainer by accommodating the end of the folded portion of the outer casing in the opening of either the first or second retaining member. Therefore, the connection is easier compared to accommodating the end of the folded portion of the outer casing in the openings of each of the first and second retaining members.

[0019] (4) In the battery described in (3) above, the outer casing may have a through hole (e.g., through hole 31 in the embodiment) that opens along the thickness direction, and the retainer may have a concave-convex structure that fits through the through hole at the part corresponding to the through hole (e.g., concave-convex structure 130 in the embodiment).

[0020] Based on this structure, the positioning between the outer casing and the retainer can be achieved using a concave-convex structure. This allows for the suppression (limitation of relative displacement) of relative positional misalignment between the outer casing and the retainer.

[0021] (5) In the battery described in (4) above, the concave-convex structure may also include: a protrusion (e.g., protrusion 131 in the embodiment), which is formed on either the first retaining member and the second retaining member and protrudes along the thickness direction; and a concave portion (e.g., concave portion 132 in the embodiment), which is formed on the other of the first retaining member and the second retaining member and is capable of being fitted by the protrusion.

[0022] According to this structure, the outer body and the retainer can be positioned by fitting the protrusion into the recess of the first retaining member or the second retaining member. Therefore, positioning becomes easier compared to the case where the concave-convex structure includes holes formed in the first retaining member and the second retaining member, as well as shaft portions passing through each hole.

[0023] (6) In the battery described in (5) above, the opening may be formed on the second retaining member, and the first retaining member may be disposed on the upper side in the vertical direction relative to the second retaining member.

[0024] According to this structure, the outer casing and the retainer can be connected by receiving the end of the folded portion of the outer casing into the opening of the second retaining member. Furthermore, in this connected state, the first retaining member covers the second retaining member from a vertically upward position relative to the second retaining member, and the protrusion is fitted into the recess of either the first or second retaining member, thereby enabling positioning between the outer casing and the retainer. Therefore, compared to the case where the first retaining member is positioned vertically downward relative to the second retaining member, the assembly process becomes easier.

[0025] (7) The all-solid-state battery (e.g., all-solid-state battery 1 in the embodiment) according to the present invention comprises: an electrode stack (e.g., electrode stack 2 in the embodiment), which comprises a positive electrode layer (e.g., positive electrode layer 6, 7 in the embodiment) formed in a plate shape, a negative electrode layer (e.g., negative electrode layer 8, 9 in the embodiment) opposite to the positive electrode layer in the thickness direction, and a solid electrolyte layer (e.g., solid electrolyte layer 11, 12 in the embodiment) disposed between the positive electrode layer and the negative electrode layer, wherein the electrode stack is formed in a cuboid shape; an outer casing of the laminate (e.g., outer casing 3 in the embodiment), which has a folded portion (e.g., folded portion 30 in the embodiment) on the long side of the electrode stack and houses the electrode stack; and a retainer (e.g., retainer 100 in the embodiment), which is disposed on the short side of the electrode stack and connected to the folded portion.

[0026] According to this structure, in an all-solid-state battery, the retainer is connected to the folded portion of the outer casing, thus eliminating the need for additional components (such as the side retainer disclosed in Patent Document 1) for connecting the outer casing to the retainer. Therefore, the number of components can be reduced. Furthermore, it contributes to energy efficiency.

[0027] (8) In the all-solid-state battery described in (7) above, the negative electrode layer may also have a negative electrode active material layer composed of active materials of lithium-based materials or silicon-based materials (for example, negative electrode active material layer 15 in the embodiment).

[0028] According to this structure, in all-solid-state batteries with Li or Si anodes, positional shifts during stacking can be suppressed.

[0029] (9) The battery module involved in the present invention (e.g., the battery module 200 in the embodiment) includes: the all-solid-state battery described in (7) or (8) above; and an elastic member (e.g., the elastic member 201 in the embodiment) adjacent to the all-solid-state battery in the thickness direction.

[0030] According to this structure, in the battery module, the retainer is connected to the folded portion of the outer casing, thereby eliminating the need for other components (such as the side retainer disclosed in Patent Document 1) for connecting the outer casing to the retainer. Therefore, the number of components can be reduced. Furthermore, this contributes to energy efficiency. Additionally, when pressurizing the all-solid-state battery and the elastic member after stacking them, damage to the all-solid-state battery or the elastic member due to the load during pressurization can be suppressed.

[0031] (10) In the battery manufacturing method of the present invention, an electrode stack (e.g., electrode stack 2 in the embodiment) formed in the shape of a cuboid is prepared, and an outer body (e.g., outer body 3 in the embodiment) having a folded portion (e.g., folded portion 30 in the embodiment) on the long side of the electrode stack and housing the laminate film of the electrode stack is prepared. A first retaining member (e.g., first retaining member 110 in the embodiment) and a second retaining member (e.g., second retaining member 120 in the embodiment) having an opening (e.g., opening 101 in the embodiment) that can accommodate the end of the folded portion are prepared as retaining members connected to the folded portion. The end of the folded portion of the outer body is accommodated in the opening of the second retaining member. With the end of the folded portion accommodated, the first retaining member is installed on the second retaining member.

[0032] According to this method, the first retaining member can be mounted on the second retaining member while the end of the folded portion of the outer casing is received in the opening of the second retaining member. Therefore, other components (such as the side retaining member disclosed in Patent Document 1) are not required for connecting the outer casing to the retaining member. This reduces the number of components. Furthermore, it contributes to energy efficiency. In addition, it saves space compared to connections using retaining mechanisms such as chuck mechanisms. This enables battery miniaturization and improves volumetric energy density efficiency.

[0033] [Invention Effects]

[0034] According to the solution of the present invention, the number of components can be reduced, which in turn contributes to energy efficiency. Attached Figure Description

[0035] Figure 1 This is a perspective view of the all-solid-state battery involved in the implementation method.

[0036] Figure 2 This is a top view showing the state in which the retaining element has been removed from the all-solid-state battery according to the embodiment.

[0037] Figure 3 It is along Figure 2 A cross-sectional view along line III-III.

[0038] Figure 4 It is along Figure 2 A cross-sectional view along line IV-IV.

[0039] Figure 5 This is an exploded perspective view of the retaining member involved in the embodiment.

[0040] Figure 6This is a perspective view showing the periphery of the folded portion of the outer casing involved in the embodiment.

[0041] Figure 7 This is a diagram illustrating the upper and lower segmented shapes of the retaining member involved in the embodiment.

[0042] Figure 8 This is a diagram illustrating one step of the battery manufacturing method involved in the embodiment.

[0043] Figure 9 This is to explain for Figure 8 The diagram shows a step in the subsequent battery manufacturing process.

[0044] Figure 10 This is a perspective view of the battery module involved in the implementation method.

[0045] Explanation of reference numerals in the attached figures:

[0046] 1. All-solid-state battery (battery)

[0047] 2 Electrode stack

[0048] 3 outer body

[0049] 6, 7 Positive electrode layers

[0050] 8, 9 Negative electrode layers

[0051] 11, 12 Solid electrolyte layers

[0052] 15. Negative electrode active material layer

[0053] 30 Folding section

[0054] 31 Through Hole

[0055] 100 retainers

[0056] 101 Opening

[0057] 110 First retaining member

[0058] 120 Second retaining member

[0059] 130 Concave-convex structure

[0060] 131 convex part

[0061] 132 recess

[0062] 200 Battery Module

[0063] 201 Elastic component. Detailed Implementation

[0064] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. In the following description, an all-solid-state battery will be used as an example of a battery. In the following description, expressions indicating relative or absolute configurations, such as "parallel," "orthogonal," "centered," and "coaxial," not only strictly refer to such configurations but also include states where relative displacement has occurred by tolerances, angles, or distances to achieve the same functionality. In the accompanying drawings used in the following description, the scale of each component has been appropriately altered to make each component easily identifiable.

[0065] <All-solid-state batteries>

[0066] Figure 1 This is a perspective view of the all-solid-state battery 1 involved in the implementation method. Figure 2 This is a top view showing the state in which the retainer 100 has been removed from the all-solid-state battery 1 according to the embodiment. Figure 3 It is along Figure 2 A cross-sectional view along line III-III. Figure 4 It is along Figure 2 A cross-sectional view along line IV-IV.

[0067] Refer to together Figures 1 to 4 The all-solid-state battery 1 has a battery body 1A and a retainer 100.

[0068] In the following explanation, an orthogonal coordinate system of X, Y, and Z will be used as needed. The X direction corresponds to the depth direction (long side) of the battery body. The Y direction corresponds to the width direction (short side) of the battery body. The Z direction corresponds to the thickness direction of the battery body. "Long side" and "short side" correspond to the long side and short side of the electrode stack, respectively. In the following explanation, the side with the arrow in the X, Y, and Z directions will be designated as the positive (+) side, and the side opposite to the arrow will be designated as the negative (-) side. The +Z side corresponds to the upper side in the vertical direction, and the -Z side corresponds to the lower side in the vertical direction.

[0069] <Battery Body>

[0070] The battery body 1A includes an electrode stack 2, an outer casing 3 covering the electrode stack 2, and lead wires 4 and 5 (positive electrode lead 4 and negative electrode lead 5) extending from the electrode stack 2 to the outside via the outer casing 3.

[0071] <Electrode Stack>

[0072] The electrode stack 2 is generally formed in a cuboid shape. The electrode stack 2 includes: positive electrode layers 6 and 7 (first positive electrode layer 6 and second positive electrode layer 7), which are formed in a plate shape; negative electrode layers 8 and 9 (first negative electrode layer 8 and second negative electrode layer 9), which are opposite to each positive electrode layer 6 and 7 in the thickness direction; and solid electrolyte layers 11 and 12 (first solid electrolyte layer 11 and second solid electrolyte layer 12), which are respectively disposed between each positive electrode layer 6 and 7 and each negative electrode layer 8 and 9.

[0073] Positive electrode layers 6 and 7 each have a positive electrode active material layer 13. Positive electrode layers 6 and 7 share a common positive electrode current collector 14. The positive electrode active material layer 13 is disposed on both sides, sandwiching the positive electrode current collector 14. Examples of active materials constituting the positive electrode active material layer 13 include lithium cobalt oxide, lithium nickel oxide, lithium manganese oxide, lithium metal phosphate, lithium nickel cobalt manganese oxide, and lithium nickel cobalt aluminum oxide.

[0074] The positive current collector 14 extends from the positive active material layer 13 in the +X direction (a direction approximately orthogonal to the stacking direction of the positive active material layer 13). The positive current collector 14 is formed of a metal foil, sheet, or plate, such as aluminum, copper, or stainless steel. It should be noted that the Z direction corresponds to the stacking direction. The XY direction, orthogonal to the stacking direction, corresponds to the planar direction.

[0075] In negative electrode layers 8 and 9, the first negative electrode layer 8 is opposite to the first positive electrode layer 6 in positive electrode layers 6 and 7 in the stacking direction. In negative electrode layers 8 and 9, the second negative electrode layer 9 is opposite to the second positive electrode layer 7 in positive electrode layers 6 and 7 in the stacking direction. The first negative electrode layer 8 is disposed on the side of the first positive electrode layer 6 opposite to the second positive electrode layer 7. The second negative electrode layer 9 is disposed on the side of the second positive electrode layer 7 opposite to the first positive electrode layer 6.

[0076] Negative electrode layers 8 and 9 each have a negative electrode active material layer 15. The area of ​​the negative electrode active material layer 15 is larger than that of the positive electrode active material layer 13. The negative electrode active material layer 15 extends beyond the positive electrode active material layer 13 in the planar direction. A gap G1 is formed between the outer peripheries of the negative electrode layers 8 and 9 in the stacking direction. The gap G1 is formed between the positive electrode layers 6 and 7 and the negative electrode layers 8 and 9 in the planar direction.

[0077] Examples of active materials constituting the negative electrode active material layer 15 include lithium-based materials and silicon-based materials. Examples of lithium-based materials include Li metal and Li alloys. Examples of silicon-based materials include Si and SiO. In addition to the above, examples of active materials constituting the negative electrode active material layer 15 include carbon materials such as graphite, soft carbon and hard carbon, tin-based materials (Sn, SnO, etc.), and lithium titanate.

[0078] Negative electrode layers 8 and 9 each have a negative electrode current collector 16 disposed on the side of the negative electrode active material layer 15 opposite to that of the positive electrode layers 6 and 7. The negative electrode current collector 16 is formed of the same material as the positive electrode current collector 14. Each negative electrode current collector 16 extends from each negative electrode active material layer 15 in the -X direction. The extension direction (-X direction) of each negative electrode current collector 16 is opposite to the extension direction (+X direction) of the positive electrode current collector 14. The leading end portion 16a of each negative electrode current collector 16 in the extension direction is disposed on the central side in the stacking direction.

[0079] The first solid electrolyte layer 11 of the solid electrolyte layers 11 and 12 is disposed between the first positive electrode layer 6 and the first negative electrode layer 8. The second solid electrolyte layer 12 of the solid electrolyte layers 11 and 12 is disposed between the second positive electrode layer 7 and the second negative electrode layer 9. The area of ​​each solid electrolyte layer 11 and 12 is the same as the area of ​​the negative electrode active material layer 15.

[0080] Each solid electrolyte layer 11, 12 is formed, for example, of a solid electrolyte having ionic conductivity. Examples of materials for the solid electrolyte layers 11, 12 include sulfide-based solid electrolyte materials, oxide-based solid electrolyte materials, nitride-based solid electrolyte materials, and halide-based solid electrolyte materials.

[0081] It should be noted that the aforementioned solid electrolyte layers 11 and 12, positive electrode active material layer 13, and negative electrode active material layer 15 can also be formed by bonding the particles of the substances constituting each layer with an organic polymer compound binder. The materials used to form each layer are not limited to those described above and can be changed according to design specifications.

[0082] <Exterior body>

[0083] The outer casing 3 has a folded portion 30 on the long side of the electrode stack 2. The outer casing 3 houses the electrode stack 2. The outer casing 3 is formed, for example, by folding the laminate 21 that forms the outer casing 3. The laminate 21 is formed, for example, by covering the front and back sides of the metal layer with a resin layer (insulating layer). By constituting the outer casing 3 with the laminate 21, the outer casing 3 has flexibility that allows it to follow the expansion and contraction of the electrode stack 2. The flexibility that allows it to follow the expansion and contraction of the electrode stack 2 can be obtained through the way the outer casing 3 wraps the electrode stack 2, the shape of the outer casing 3, the structure, etc.

[0084] The outer casing 3 has: a cover portion 51 that covers the entire electrode stack 2; and a peripheral portion 52 formed around the cover portion 51. The cover portion 51 and the peripheral portion 52 are integrally formed. The cover portion 51 is formed in a cuboid shape corresponding to the shape of the electrode stack 2. The cover portion 51 has: a pair of end face cover portions 53 that cover the negative electrode current collector 16 from the outside in the stacking direction; and a side cover portion 54 that is combined with the outer periphery of the pair of end face cover portions 53 and covers the outer periphery 2a of the electrode stack 2. The end face cover portions 53 and the side cover portions 54 are integrally formed.

[0085] The outer peripheral portion 2a of the electrode stack 2 is the outer side portion in the planar direction. The side covering portion 54 has a long side covering portion 54a facing each other in the short side direction when viewed from the stacking direction, and a pair of short side covering portions 54b facing each other in the long side direction.

[0086] The peripheral portion 52 is formed by overlapping the peripheral edge of the side cover portion 54 on the side opposite to the end face cover portion 53 in the lamination direction. The peripheral portion 52 has a pair of long peripheral portions 52a formed on the side of the long side cover portion 54a and a pair of short peripheral portions 52b formed on the side of the short side cover portion 54b. Each peripheral portion 52a, 52b is formed at the center of the lamination direction in each side cover portion 54a, 54b.

[0087] exist Figure 2 In the example, one of the pair of long perimeter portions 52a has a remaining portion 50 that is larger than the remaining portion of the long perimeter portion 52a. A bent portion 55 is formed by folding the remaining portion 50 (the remaining portion of the long perimeter portion 52a). In this embodiment, the bent portion 55 (folded portion 30) is formed by folding the remaining portion 50 of each of the pair of long perimeter portions 52a. It should be noted that the shape obtained by combining the shorter perimeter portion 52b, which is longer in the Y direction, and the folded portions 30 on both sides in the Y direction forms an I-shape (H-shape) that is longer in the Y direction when viewed from the X direction.

[0088] <Folding section>

[0089] The folded portion 30 is formed by a bending portion 55. The bending portion 55 has: a first extension 57 that extends from the root portion 56 of the remaining portion 50 near the outer periphery 2a of the electrode laminate 2; a second extension 58 that extends from the front end portion 57a ​​of the first extension 57 on the side opposite to the root portion 56; and a third extension 59 that extends from the front end portion 58a of the second extension 58 on the side opposite to the first extension 57. The root portion 56, the first extension 57, the second extension 58, and the third extension 59 constitute the folded portion 30.

[0090] The first extension 57 extends from the root 56 toward the -Z direction. The first extension 57 is formed flat along the stacking direction. A gap G2 is formed between the first extension 57 and the long side cover 54a. The first extension 57 may also extend outward in the stacking direction than the negative electrode current collector 16 when viewed from the surface direction. The front end portion 57a ​​of the first extension 57 may also be disposed outward in the stacking direction of the electrode stack 2 when viewed from the surface direction.

[0091] The second extension 58 extends from the front end portion 57a ​​of the first extension 57 in the +Z direction. The second extension 58 is formed flatly along the stacking direction. The second extension 58 is disposed on the side of the first extension 57 opposite to the electrode stack 2. The second extension 58 may also extend outward in the stacking direction than the negative current collector 16 when viewed from the surface direction. The front end portion 58a of the second extension 58 may also be disposed on the outer side of the electrode stack 2 opposite to the front end portion 57a ​​of the first extension 57 when viewed from the surface direction. The length L between the front end portion 57a ​​of the first extension 57 and the front end portion 58a of the second extension 58 may also be longer than the thickness H of the electrode stack 2.

[0092] The third extension 59 extends from the front end portion 58a of the second extension 58 in the -Z direction. The third extension 59 is formed flatly along the stacking direction. The third extension 59 is disposed on the side of the second extension 58 near the electrode stack 2. The third extension 59 and the first extension 57 are disposed on the same plane in the stacking direction. The third extension 59 extends to the front of the root 56. The front end portion 59a of the third extension 59 is disposed close to the root 56.

[0093] <Leader splice>

[0094] The lead contacts 4 and 5 are formed, for example, from conductive metal sheets or plates. Lead contacts 4 and 5 are respectively a positive electrode contact 4 and a negative electrode contact 5 extending along the surface direction. The battery body is connected to a charger or electrical load via the two lead contacts 4 and 5, thereby enabling charging or discharging of the electrode stack 2.

[0095] One end (-X end) of the positive electrode contact 4 is connected to the front end 14a of the positive current collector 14. The front end 14a of the positive current collector 14 is connected to one side (-Z side) of one end (-X end) of the positive electrode contact 4. The other end (+X end) of the positive electrode contact 4 is led out to the outside of the outer casing 3 via the short peripheral portion 52b of the outer casing 3.

[0096] One end (+X end) of the negative electrode contact 5 is connected to the front end 16a of the negative current collector 16. The front end 16a of the negative current collector 16 is connected to both sides (+Z side and -Z side) of one end (+X end) of the negative electrode contact 5. The lead-out direction (-X direction) of the negative electrode contact 5 is opposite to the lead-out direction (+X direction) of the positive electrode contact 4. The other end (-X end) of the negative electrode contact 5 is led out to the outside of the outer casing 3 via the short peripheral edge 52b of the outer casing 3.

[0097] <Retaining component>

[0098] Figure 5 This is an exploded perspective view of the retaining member 100 according to the embodiment. Figure 6 This is a perspective view showing the periphery of the folded portion 30 of the outer casing 3 involved in the embodiment.

[0099] Refer to together Figure 5 and Figure 6 The retainer 100 is disposed on the short side of the electrode laminate 2. The retainer 100 is disposed on both sides of the long side (X direction) of the battery body 1A. The retainer 100 overlaps with the short peripheral portions 52b on both sides of the battery body 1A in the X direction. The retainer 100 is configured to surround the lead contacts 4 and 5 respectively. An opening 101 is formed in the retainer 100 to receive the end of the folded portion 30.

[0100] The retainer 100 includes a first retaining member 110 and a second retaining member 120 that are arranged overlapping each other in the thickness direction of the electrode laminate 2. The retainer 100 is formed by combining the first retaining member 110 and the second retaining member 120. Stepped portions 111 and 121 are formed on the faces of the first retaining member 110 and the second retaining member 120 facing each other in the Z direction, respectively, at their central Y-direction sides. A gap is formed between the first retaining member 110 and the second retaining member 120 in the Z direction by the stepped portions 111 and 121. The gap allows the lead contacts 4 and 5 to be arranged via the short peripheral portion 52b when the first retaining member 110 and the second retaining member 120 are combined.

[0101] The first retaining member 110 and the second retaining member 120 are preferably made of a material (e.g., a resin material with a specified strength) that can ensure the rigidity of the laminate 21 (outer body 3) in the battery body 1A. Examples of materials constituting the first retaining member 110 and the second retaining member 120 include thermoplastic resins such as polypropylene, polyethylene, and polyphenylene sulfide, thermosetting resins such as phenolic resins and epoxy resins.

[0102] An opening 101 is formed in either the first retaining member 110 or the second retaining member 120. In this embodiment, the opening 101 is formed in the second retaining member 120. The first retaining member 110 is disposed above the second retaining member 120 in the vertical direction.

[0103] A through hole 31 is formed in the outer casing 3, opening along the thickness direction. The through hole 31 is formed on the outer side of the short periphery 52b in the Y direction (the part that does not overlap with the lead wire contacts 4 and 5 when viewed from above). The through hole 31 is circular in shape when viewed from above. There is one through hole 31 on each of the two outer sides of the short periphery 52b in the Y direction. It should be noted that the formation of the through hole 31 (configuration, shape, number, etc.) is not limited to the above and can be changed according to the design specifications.

[0104] The retainer 100 has a convex-concave structure 130 at a location corresponding to the through hole 31, which engages with the through hole 31. The convex-concave structure 130 includes: a protrusion 131 formed in either the first retainer 110 or the second retainer 120, protruding along the thickness direction; and a recess 132 formed in the other of the first retainer 110 and the second retainer 120, which is capable of engaging with the protrusion 131. In this embodiment, the protrusion 131 is formed in the first retainer 110, and the recess 132 is formed in the second retainer 120.

[0105] <The upper and lower split structure of the retainer>

[0106] Figure 7 This is a diagram illustrating the upper and lower segmented shape of the retaining member 100 according to the embodiment.

[0107] Refer to together Figure 7 The retainer 100 is formed by combining a first retaining member 110 and a second retaining member 120 that are divided in the vertical direction. The shape formed by combining the first retaining member 110 and the second retaining member 120 is formed into an I-shape (H-shape) that is longer in the Y direction when viewed from the X direction.

[0108] The first retaining member 110 is a member that constitutes the +Z side portion (upper part) of the retainer 100 and has a protrusion 131 that constitutes the concave-convex structure 130. The first retaining member 110 is disposed on the upper side of the lead contacts 4, 5, separated by a short peripheral portion 52b. The lower surface 112 of the first retaining member 110, which is located on the outer side in the Y direction (the portion that does not overlap with the lead contacts 4, 5 in plan view), is formed flat along the surface direction.

[0109] The second retaining member 120 is a member that constitutes the -Z side portion (lower part) and the outer end portion in the Y direction (the part forming the opening 101) of the retaining member 100, and has a recess 132 that constitutes the concave-convex structure 130. The second retaining member 120 is disposed on the lower side of the lead contacts 4, 5 with respect to the short peripheral portion 52b. The upper surface 124 of the second retaining member 120, which is located on the outer side in the Y direction (the portion that does not overlap with the lead contacts 4, 5 in plan view), is formed flat along the surface direction.

[0110] The second retaining member 120 includes: a transverse wall portion 122 having a long side in the Y direction; and a longitudinal wall portion 123 connecting the two ends of the transverse wall portion 122 in the Y direction and having a long side in the Z direction. The shape of the second retaining member 120 (the shape obtained by combining the transverse wall portion 122 that is long in the Y direction with the longitudinal wall portions 123 on both sides in the Y direction) is formed as an I-shape (H-shape) that is long in the Y direction when viewed from the X direction. The transverse wall portion 122 is the portion of the second retaining member 120 that is opposite to the first retaining member 110 in the Z direction. The longitudinal wall portion 123 is the portion of the second retaining member 120 in which the opening 101 is formed. The longitudinal wall portion 123 is formed as a cuboid that is long in the X direction, corresponding to the shape of the folding portion 30.

[0111] The opening 101 opens the -X side portion of the longitudinal wall portion 123 in the -X direction. When viewed from the X direction, the opening 101 is T-shaped. The opening 101 is formed by combining a longitudinal hole 102 and a transverse hole 103. When viewed from the X direction, the longitudinal hole 102 is a long hole (elongated hole) in the Z direction, corresponding to the shape of the folded portion 30, and the transverse hole 103 is a hole in the Y direction, corresponding to the short peripheral portion 52b.

[0112] A protrusion 131 is formed on the outer side of the first retaining member 110 in the Y direction (the portion that does not overlap with the lead wire contacts 4 and 5 in plan view). The protrusion 131 protrudes downward from the lower surface 112 on the outer side of the first retaining member 110 in the Y direction compared to the stepped portion 111. In plan view, the protrusion 131 is formed in the first retaining member 110 at the location coinciding with the through hole 31. The protrusion 131 is circular in plan view. One protrusion 131 is formed on each of the two outer sides of the first retaining member 110 in the Y direction. It should be noted that the formation (configuration, shape, number, etc.) of the protrusion 131 is not limited to the above and can be changed according to design specifications.

[0113] Recess 132 is formed on the outer side of the second retaining member 120 in the Y direction (the portion that does not overlap with the lead wire contacts 4 and 5 in plan view). Recess 132 is formed by a hole that opens along the Z direction in the portion of the transverse wall portion 122 of the second retaining member 120 that is further outward in the Y direction than the stepped portion 121. In plan view, recess 132 is formed in the transverse wall portion 122 of the second retaining member 120 at the location coinciding with the through hole 31. Recess 132 is circular in plan view. One recess 132 is formed on each of the two outer sides of the transverse wall portion 122 of the second retaining member 120 in the Y direction. It should be noted that the formation (configuration, shape, number, etc.) of recess 132 is not limited to the above and can be changed according to design specifications.

[0114] The protrusion 131 is formed in a stepped shape in cross-section. The protrusion 131 in cross-section ( Figure 7 The YZ cross-section shown includes an enlarged diameter portion 131a, a reduced diameter portion 131b with a smaller diameter compared to the enlarged diameter portion 131a, and a connecting portion 131c connecting the enlarged diameter portion 131a and the reduced diameter portion 131b. The enlarged diameter portion 131a is formed as a cylinder with an outer diameter approximately the same as the inner diameter of the through hole 31. The reduced diameter portion 131b is formed as a cylinder with an outer diameter approximately the same as the inner diameter of the recess 132 (hole 132b). The connecting portion 131c is formed as a frustum-shaped cone with its diameter gradually decreasing from the lower end of the enlarged diameter portion 131a to the upper end of the reduced diameter portion 131b. It should be noted that the configuration of the protrusion 131 is not limited to the above and can be changed according to design specifications.

[0115] Recess 132 in section view ( Figure 7 The recess 132, as shown in the YZ cross-section, is formed in a conical shape. In cross-section, the recess 132 includes a conical portion 132a and a hole 132b connected to the conical portion 132a. In cross-section, the conical portion 132a is formed in a frustum-shaped manner along the connecting portion 131c of the protrusion 131, with its diameter gradually decreasing from the upper surface 124 of the transverse wall portion 122 of the second retaining member 120, which is further outward in the Y direction than the stepped portion 121, towards the upper end of the hole 132b. The hole 132b has an inner diameter that is substantially the same as the outer shape of the tapered portion 131b of the protrusion 131. It should be noted that the configuration of the recess 132 is not limited to the above and can be varied according to design specifications.

[0116] In this embodiment, the outer body 3 can be connected to the second retaining member 120 by accommodating the end of the folded portion 30 of the outer body 3 into the opening 101 of the longitudinal wall portion 123 of the second retaining member 120. Furthermore, in this connected state, the first retaining member 110 covers the transverse wall portion 122 of the second retaining member 120 from the vertical direction upwards, passing through the through hole 31 of the outer body 3 (short periphery portion 52b). Moreover, the protrusion 131 of the first retaining member 110 can be fitted into the recess 132 of the transverse wall portion 122 of the second retaining member 120. Thus, positioning between the outer body 3 and the retaining member 100 is possible. For example, during module assembly (stacking / pressurization), positioning can be achieved at the four corners of the battery body 1A.

[0117] For example, when a load is applied due to buckling, the periphery of the through hole 31 of the outer body 3 (short periphery portion 52b) is stressed, deformed, and its position becomes uncertain. In contrast, in this embodiment, the rigidity is improved by connecting the folded portion 30, which has particularly high strength in the outer body 3, to the second retaining member 120 constituting the retaining member 100, thereby suppressing deformation under the input load (buckling load). In addition, positional accuracy during assembly can be ensured, preventing interference with surrounding components.

[0118] <Battery Manufacturing Method>

[0119] Figure 8 This is a diagram illustrating one step of the battery manufacturing method involved in the embodiment. Figure 9 This is to explain for Figure 8 The diagram shows a step in the subsequent battery manufacturing process.

[0120] Refer to together Figure 8 and Figure 9 In the battery manufacturing method of this embodiment, an electrode laminate 2 formed in the shape of a cuboid and an outer casing 3 having a folded portion 30 on the long side of the electrode laminate 2 and housing the laminate film of the electrode laminate 2 are prepared. A first retaining member 110 and a second retaining member 120 having an opening 101 that can accommodate the end of the folded portion 30 are prepared as retaining members 100 connected to the folded portion 30. The end of the folded portion 30 of the outer casing 3 is accommodated in the opening 101 of the second retaining member 120. With the end of the folded portion 30 accommodated, the first retaining member 110 is mounted on the second retaining member 120.

[0121] First, the end of the folded portion 30 of the outer casing 3 constituting the battery body 1A is received (inserted) into the opening 101 of the longitudinal wall portion 123 of the second retaining member 120 located on the lower side in the vertical direction. For example, the ends of each folded portion 30 on both sides of the Y direction of the outer casing 3 are received into the openings 101 of the longitudinal wall portions 123 on both sides of the Y direction of the second retaining member 120, and moved to a predetermined position in the X direction. Thus, each folded portion 30 of the outer casing 3 is received in each opening 101 of the longitudinal wall portion 123 (the state in which each folded portion 30 of the outer casing 3 is inserted).

[0122] Next, the first retaining member 110 is positioned vertically upwards over the transverse wall portion 122 of the second retaining member 120, covering the transverse wall portion 122 via the outer body 3 (short peripheral portion 52b). At this time, the protrusion 131 of the first retaining member 110 is fitted into the recess 132 of the transverse wall portion 122 of the second retaining member 120 through the through hole 31 of the outer body 3 (short peripheral portion 52b). This allows for positioning between the outer body 3 and the retaining member 100.

[0123] Through the above processes, the manufacturing of the all-solid-state battery 1, which includes the battery body and the retainer 100, is completed.

[0124] In this embodiment, compared to the installation of the first retaining member 110, the end of the folded portion 30 of the outer body 3 is first accommodated in the opening 101 of the lower second retaining member 120. This prevents the periphery of the through hole 31 of the outer body 3 (short peripheral portion 52b) from being subjected to load. As a result, deformation under input load (bending load) can be suppressed, ensuring positional accuracy during assembly and preventing interference with surrounding components.

[0125] <Battery Module>

[0126] Figure 10 This is a perspective view of the battery module 200 involved in the implementation method.

[0127] like Figure 10 As shown, the battery module 200 includes the aforementioned all-solid-state battery 1 and an elastic member 201 adjacent to the all-solid-state battery 1 in the thickness direction. The battery module 200 is formed by alternating (stacking) multiple all-solid-state batteries 1 and elastic members 201.

[0128] exist Figure 10In this example, the battery module 200 includes a first plate-shaped member 211, a second plate-shaped member 212 opposite to the first plate-shaped member 211 in the thickness direction, and a third plate-shaped member 213 disposed between the first plate-shaped member 211 and the second plate-shaped member 212. Multiple elastic members 201 are disposed between the first plate-shaped member 211 and the third plate-shaped member 213, and between the second plate-shaped member 212 and the third plate-shaped member 213, and an all-solid-state battery 1 is disposed between adjacent elastic members 201. It should be noted that the arrangement of each plate-shaped member is not limited to the above and can be changed according to design specifications.

[0129] <Effects>

[0130] As described above, the all-solid-state battery 1 of the above embodiment includes: an electrode stack 2, which is formed in the shape of a cuboid; an outer casing 3 of a laminate, which has a folded portion 30 on the long side of the electrode stack 2 and houses the electrode stack 2; and a retainer 100, which is disposed on the short side of the electrode stack 2 and connected to the folded portion 30.

[0131] According to this structure, by connecting the retainer 100 to the folding portion 30 of the outer body 3, other components (such as the side retainer disclosed in Patent Document 1) are not required for connecting the outer body 3 to the retainer 100. Therefore, the number of parts can be reduced. Moreover, it also contributes to energy efficiency.

[0132] In the above embodiment, the retainer 100 has an opening 101 for receiving the end of the folded portion 30.

[0133] According to this structure, the outer casing 3 can be connected to the retainer 100 by accommodating the end of the folded portion 30 of the outer casing 3 into the opening 101 of the retainer 100. Therefore, compared with the case where the connection is made by a retaining mechanism such as a chuck mechanism, it helps to save space. As a result, the battery can be miniaturized and the volumetric energy density efficiency can be improved.

[0134] In the above embodiment, the retainer 100 includes a first retainer 110 and a second retainer 120 arranged overlapping each other in the thickness direction of the electrode laminate 2. An opening 101 is formed in the second retainer 120.

[0135] According to this structure, by overlapping each other in the thickness direction of the electrode laminate 2 with the first retaining member 110 and the second retaining member 120, the outer casing 3 can be more appropriately protected from external factors. Furthermore, the outer casing 3 can be connected to the retainer 100 by accommodating the end of the folded portion 30 of the outer casing 3 in the opening 101 of the second retaining member 120. Therefore, the connection is easier compared to the case where the end of the folded portion 30 of the outer casing 3 is accommodated in the openings of the first retaining member 110 and the second retaining member 120 respectively.

[0136] In the above embodiment, a through hole 31 opening along the thickness direction is formed in the outer body 3. The retainer 100 has a concave-convex structure 130 that fits through the through hole 31 at the portion corresponding to the through hole 31.

[0137] According to this structure, the concave-convex structure 130 can be used to position the outer body 3 and the retainer 100. As a result, the relative positional displacement between the outer body 3 and the retainer 100 can be suppressed (relative displacement is limited).

[0138] In the above embodiment, the concave-convex structure 130 includes: a protrusion 131 formed on the first retaining member 110 and protruding along the thickness direction; and a concave portion 132 formed on the second retaining member 120 and capable of being fitted with the protrusion 131.

[0139] According to this structure, the outer body 3 and the retainer 100 can be positioned by fitting the protrusion 131 of the first retaining member 110 into the recess 132 of the second retaining member 120. Therefore, positioning becomes easier compared to the case where the concave-convex structure 130 includes holes formed in the first retaining member 110 and the second retaining member 120, and shaft portions passing through each hole.

[0140] In the above embodiment, the first retaining member 110 is disposed above the second retaining member 120 in the vertical direction.

[0141] According to this structure, the outer body 3 and the retainer 100 can be connected by receiving the end of the folded portion 30 of the outer body 3 into the opening 101 of the second retaining member 120. Furthermore, in this connected state, the first retaining member 110 covers the second retaining member 120 from the vertical direction upward relative to the second retaining member 120, and the protrusion 131 of the first retaining member 110 is fitted into the recess 132 of the second retaining member 120, thereby enabling positioning between the outer body 3 and the retainer 100. Therefore, compared to the case where the first retaining member 110 is positioned vertically downward relative to the second retaining member 120, the assembly operation becomes easier.

[0142] The all-solid-state battery 1 of the above embodiment includes: an electrode stack 2 having a plate-shaped positive electrode layer 6, 7, a negative electrode layer 8, 9 opposite to the positive electrode layer 6, 7 in the thickness direction, and solid electrolyte layers 11, 12 disposed between the positive electrode layer 6, 7 and the negative electrode layer 8, 9, the electrode stack 2 being formed in a cuboid shape; an outer casing 3 of a laminate having a folded portion 30 on the long side of the electrode stack 2 and housing the electrode stack 2; and a retainer 100 disposed on the short side of the electrode stack 2 and connected to the folded portion 30.

[0143] According to this structure, in the all-solid-state battery 1, the retainer 100 is connected to the folded portion 30 of the outer body 3, thereby eliminating the need for other components (such as the side retainer disclosed in Patent Document 1) for connecting the outer body 3 to the retainer 100. Therefore, the number of components can be reduced. Furthermore, it contributes to energy efficiency.

[0144] In the above embodiments, the negative electrode layers 8 and 9 have a negative electrode active material layer 15 composed of an active material made of lithium-based or silicon-based materials.

[0145] According to this structure, in an all-solid-state battery 1 with a Li or Si anode, positional shift during stacking can be suppressed.

[0146] The battery module 200 of the above embodiment includes the all-solid-state battery 1 and an elastic member 201 adjacent to the all-solid-state battery 1 in the thickness direction.

[0147] According to this structure, in the battery module 200, the retainer 100 is connected to the folded portion 30 of the outer body 3, thereby eliminating the need for other components (such as the side retainer disclosed in Patent Document 1) for connecting the outer body 3 to the retainer 100. Therefore, the number of components can be reduced. Furthermore, this contributes to energy efficiency. Additionally, when the all-solid-state battery 1 and the elastic member 201 are stacked and pressurized, damage to the all-solid-state battery 1 or the elastic member 201 due to the load during pressurization can be prevented.

[0148] In the battery manufacturing method of the above embodiment, an electrode laminate 2 formed into a cuboid shape and an outer casing 3 having a folded portion 30 on the long side of the electrode laminate 2 and housing the laminate film of the electrode laminate 2 are prepared. A first retaining member 110 and a second retaining member 120 having an opening 101 that can accommodate the end of the folded portion 30 are prepared as retaining members 100 connected to the folded portion 30. The end of the folded portion 30 of the outer casing 3 is accommodated in the opening 101 of the second retaining member 120. With the end of the folded portion 30 accommodated, the first retaining member 110 is mounted on the second retaining member 120.

[0149] According to this method, the first retaining member 110 can be mounted on the second retaining member 120 while the end of the folded portion 30 of the outer casing 3 is housed in the opening 101 of the second retaining member 120. Therefore, other components (such as the side retaining member disclosed in Patent Document 1) are not required for connecting the outer casing 3 to the retaining member 100. This reduces the number of components. Furthermore, it contributes to energy efficiency. In addition, it saves space compared to connections using retaining mechanisms such as chuck mechanisms. This allows for battery miniaturization and improved volumetric energy density efficiency.

[0150] <Variation Example>

[0151] In the above embodiments, an example of having an opening in the retainer to receive the end of the folded portion has been described, but this is not a limitation. For example, the retainer may also have a portion that can hold the folded portion. The form in which the retainer connects to the folded portion of the outer casing may be varied according to design specifications.

[0152] In the above embodiments, an example has been described where the retaining member includes a first retaining member and a second retaining member arranged overlapping each other in the thickness direction of the electrode laminate, and an opening is formed in the second retaining member, but this is not a limitation. For example, the opening may also be formed in the first retaining member. For example, the opening may be formed in both the first retaining member and the second retaining member. The shape of the opening may be varied according to design specifications.

[0153] In the above embodiments, an example was given in which a through hole is formed in the outer casing along the thickness direction, and the retainer has a concave-convex structure that fits into the through hole at the corresponding location, but this is not a limitation. For example, a through hole opening along the thickness direction may not be formed in the outer casing. For example, the retainer may not have a concave-convex structure at the corresponding location. The formation of the through hole and the arrangement of the concave-convex structure can be changed according to design specifications.

[0154] In the above embodiments, an example of a concave-convex structure including a protrusion formed in the first retaining member and protruding along the thickness direction, and a recess formed in the second retaining member that can be fitted with the protrusion, has been described, but is not limited thereto. For example, the concave-convex structure may also include a protrusion formed in the second retaining member and protruding along the thickness direction, and a recess formed in the first retaining member that can be fitted with the protrusion. For example, the concave-convex structure may also be configured to include holes formed in the first and second retaining members, and shaft portions passing through each hole. The configuration of the concave-convex structure may be varied according to design specifications.

[0155] In the above embodiments, an example has been described where the first retaining member is positioned above the second retaining member in the vertical direction, but this is not a limitation. For example, the first retaining member may also be positioned below the second retaining member in the vertical direction. The configuration of the first retaining member relative to the second retaining member may be varied according to design specifications.

[0156] In the above embodiments, an all-solid-state battery was described as an example of a battery, but it is not a limitation. For example, the battery may also be a lithium-ion secondary battery, a nickel-metal hydride battery, or other secondary batteries. The battery may also be a battery other than an all-solid-state battery or a secondary battery. For example, the battery to which the present invention is applicable may be modified according to design specifications.

[0157] The above describes specific embodiments of the present invention, but the present invention is not limited to such embodiments in any way. Various modifications and substitutions can be made without departing from the spirit of the present invention.

Claims

1. A battery, wherein, The battery has the following features: The electrode stack is formed in a cuboid shape; An outer casing for a laminated film has a folded portion on the long side of the electrode stack and houses the electrode stack; and A retainer is disposed on the short side of the electrode stack and connected to the fold.

2. The battery according to claim 1, wherein, The retainer has an opening that accommodates the end of the folded portion.

3. The battery according to claim 2, wherein, The retaining member includes a first retaining member and a second retaining member that are arranged overlapping each other in the thickness direction of the electrode laminate. The opening is formed in either the first retaining member or the second retaining member.

4. The battery according to claim 3, wherein, A through hole is formed in the outer casing, opening along the thickness direction. The retainer has a concave-convex structure at the location corresponding to the through hole, which fits into the through hole.

5. The battery according to claim 4, wherein, The concave-convex structure includes: A protrusion formed in either the first retaining member or the second retaining member, and projecting along the thickness direction; and A recess is formed in the other of the first retaining member and the second retaining member, and is capable of being fitted with the protrusion.

6. The battery according to claim 5, wherein, The opening is formed in the second retaining member. The first retaining member is positioned above the second retaining member in the vertical direction.

7. An all-solid-state battery, wherein, The all-solid-state battery has the following features: An electrode stack comprising a plate-shaped positive electrode layer, a negative electrode layer opposite the positive electrode layer in the thickness direction, and a solid electrolyte layer disposed between the positive electrode layer and the negative electrode layer, the electrode stack being formed in a cuboid shape; An outer casing for a laminated film has a folded portion on the long side of the electrode stack and houses the electrode stack; and A retainer is disposed on the short side of the electrode stack and connected to the fold.

8. The all-solid-state battery according to claim 7, wherein, The negative electrode layer has a negative electrode active material layer composed of lithium-based or silicon-based active materials.

9. A battery module, wherein, The battery module includes: The all-solid-state battery as described in claim 7 or 8; and An elastic member adjacent to the all-solid-state battery in the thickness direction.

10. A method for manufacturing a battery, wherein, An electrode laminate in the shape of a cuboid is prepared, and an outer casing having a folded portion on the long side of the electrode laminate and housing the laminate film of the electrode laminate is prepared. Furthermore, a first retaining member and a second retaining member having an opening capable of receiving the end of the folded portion are prepared as retaining members connected to the folded portion. The end of the folded portion of the outer casing is received into the opening of the second retaining member. With the end containing the folded portion, the first retaining member is mounted on the second retaining member.

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