Manufacturing method of laminated battery

The laminated battery design with angled and rolled portions addresses stress concentration issues, enhancing structural efficiency and preventing tears in the laminate film.

JP7772039B2Active Publication Date: 2025-11-18TOYOTA JIDOSHA KK
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Patent Information

Application Number
JP2023122778
Authority / Receiving Office
JP · JP
Patent Type
Patents
Current Assignee / Owner
Filing Date
2023-07-27
Publication Date
2025-11-18
Estimated Expiration
2043-07-27

AI Technical Summary

Technical Problem

Conventional laminated batteries face issues with stress concentration at the bent portions of the laminate film, leading to tears and compromising structural efficiency.

Method used

The laminated battery design incorporates two bent portions bent at angles of 90° or less and a rolled portion, with a rolling process forming the fused portion into a roll shape followed by pressing from multiple directions to create the bent portions, mitigating stress concentration.

Benefits of technology

This design enhances structural efficiency while preventing tears in the laminate film, improving the overall integrity of the battery.

✦ Generated by Eureka AI based on patent content.

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Patent Text Reader

Abstract

To provide a laminate battery which can increase the structural efficiency of a fusion part and also can suppress generation of breakage of a laminate film at the same time.SOLUTION: The laminate battery includes: an electrode body; and a laminate film for sealing the electrode body by covering the electrode body. The laminate film has a fusion part in which end parts are overlapped with each other and the inner surface is fused. The fusion part includes: two bending parts bent to form an angle of 90 degrees at a maximum or to form an arc; and a roll part arranged closer to the end of the fusion part than the two bending parts, the roll part being rolled.SELECTED DRAWING: Figure 1
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Description

[Technical Field]

[0001] The present disclosure relates to a laminated battery and a method for manufacturing a laminated battery. [Background technology]

[0002] In a laminated battery in which an electrode body is covered with a laminated film, a fused portion is formed by fusing a portion of the laminated film to enclose the electrode body.

[0003] For example, Patent Document 1 discloses a method for manufacturing a secondary battery having a folded portion at at least one end in a laminated outer casing, the method comprising the steps of: abutting a pressure plate against the base point of the fold at the end of the outer casing; and, after the abutting step, sliding the pressure plate and a pressing plate positioned opposite the pressure plate so as to sandwich the end, bending the end around the base point, and clamping the end between the pressure plate and the pressing plate to form the folded portion. The surface of the pressing plate that slides against the end has an inclined surface that bends the end and a clamping surface that clamps the end, and the inclined surface is inclined so that the cross-sectional area of ​​the pressing plate narrows in the sliding direction in a cross section perpendicular to the width direction of the pressing plate, and the inclined surface is inclined in the width direction. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 2019-200973 Summary of the Invention [Problem to be solved by the invention]

[0005] Conventionally, the fused portion of the laminate film in laminated batteries has been required to save space and thereby improve structural efficiency, and to achieve this, a bent portion has been formed by folding a part of the fused portion, but stress concentration at this bent portion can cause tears in the laminate film.

[0006] The present disclosure has been made in consideration of the above-described situation, and aims to provide a laminated battery that can improve the structural efficiency of the fused portion while suppressing the occurrence of tears in the laminate film, and a method for manufacturing such a laminated battery. [Means for solving the problem]

[0007] <1> An electrode body; a laminate film that covers and encapsulates the electrode body, The laminate film has a fused portion where the ends are overlapped and the inner surfaces are fused together, The fused portion is a laminated battery having two bent portions bent into an angular or arc shape at an angle of 90° or less, and a roll portion that is positioned closer to the tip of the fused portion than the two bent portions and is rolled up into a roll. <2> The angle of the bent portion is 60° or more. <1> 2. The laminated battery according to claim 1. <3> the height of the fused portion in the thickness direction of the electrode body is equal to or less than the thickness of a portion of the laminated battery having the electrode body; <1> or <2> 2. The laminated battery according to claim 1. <4> An electrode body; a laminate film that covers and encapsulates the electrode body, A method for manufacturing a laminated battery having a fused portion in which end portions of the laminate film are overlapped and inner surfaces are fused, a rolling step of rolling the fused portion into a roll from the tip side; a pressing step in which press members are pressed against the rolled fused portion from at least two directions to bend it into an angular or arc shape at an angle of 90° or less, thereby forming two bent portions. <5> The pressing step is a step of pressing the press members from three directions. <4> A method for manufacturing the laminated battery according to claim 1. [Effects of the Invention]

[0008] According to the present disclosure, it is possible to provide a laminated battery that can improve the structural efficiency of the fused portion while suppressing the occurrence of tears in the laminate film, and a method for manufacturing the laminated battery. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a schematic cross-sectional view illustrating a laminated battery according to an embodiment of the present disclosure. [Figure 2] 1 is a schematic cross-sectional view illustrating one step of a method for manufacturing a laminated battery according to an embodiment of the present disclosure. [Figure 3] 1 is a schematic cross-sectional view illustrating one step of a method for manufacturing a laminated battery according to an embodiment of the present disclosure. [Figure 4] 1A and 1B are a schematic top view and a schematic cross-sectional view illustrating a rolling step in a manufacturing method for a laminated battery according to an embodiment of the present disclosure. [Figure 5] 1 is a schematic cross-sectional view illustrating one step of a method for manufacturing a laminated battery according to an embodiment of the present disclosure. [Figure 6] FIG. 1 is a schematic cross-sectional view showing an example of a solid-state battery. DETAILED DESCRIPTION OF THE INVENTION

[0010] <Laminated battery> A laminated battery according to an embodiment of the present disclosure includes an electrode assembly and a laminate film that covers and encapsulates the electrode assembly. The laminate film has a fused portion where the edges are overlapped and the inner surfaces are fused together. The fused portion has two bent portions that are bent into an angular or arc shape at angles of 90° or less, and a rolled portion that is located closer to the tip of the fused portion than the two bent portions and is rolled up into a roll.

[0011] Hereinafter, an embodiment of a laminated battery according to an embodiment of the present disclosure will be described with reference to the drawings. The drawings shown below are schematic illustrations, and the size and shape of each part are appropriately exaggerated to facilitate understanding.

[0012] FIG. 1 is a schematic cross-sectional view illustrating a laminated battery according to an embodiment of the present disclosure. The laminated battery 10 shown in FIG. 1 includes an electrode assembly 2 and a laminate film 4 that covers and encapsulates the electrode assembly 2. The laminate film 4 has a fused portion 40 where the edges are overlapped and the inner surfaces are fused together. The fused portion 40 has two bent portions 40A, 40B that are bent into an angular or arc shape at an angle of 90° or less, and a rolled portion 40C that is positioned closer to the tip 40D of the fused portion 40 than the two bent portions 40A, 40B and is rolled into a roll. The rolled portion 40C is rolled toward the inside of the fused portion 40 that has the two bent portions 40A, 40B (i.e., toward the side where the two bent portions 40A, 40B form an angle of 90° or less). The rolled portion refers to a portion with a continuous curved shape.

[0013] The laminated battery according to the embodiment of the present disclosure has the above-described configuration, which makes it possible to improve the structural efficiency of the fused portion and suppress the occurrence of tears in the laminate film.

[0014] First, the laminated battery according to the embodiment of the present disclosure has a rolled-up portion at the tip end of the fused portion, which allows for space saving and improves the structural efficiency of the fused portion. Furthermore, because the laminated battery has a rolled portion closer to the tip of the fused portion than the two bent portions, the structural efficiency can be improved as described above even if the bending angles at the two bent portions are not extremely acute (e.g., bent portions with an angle of 0°). Bent portions with extremely acute angles (e.g., an angle of 0°) can cause stress to concentrate at the acute corners, which can lead to tears in the laminate film. However, in the embodiment of the present disclosure, the structural efficiency can be improved even if the bending angles at the two bent portions are not extremely acute, thereby mitigating stress concentration at the corners and suppressing the occurrence of tears in the laminate film.

[0015] From the above, it is presumed that the laminated battery according to the embodiment of the present disclosure can improve the structural efficiency of the fused portion while suppressing the occurrence of tears in the laminate film.

[0016] Bending angle The two bent portions are bent into an angular or arc shape such that the angles (for example, in the laminated battery 10 shown in FIG. 1, the angles are angle a at bent portion 40A and angle b at bent portion 40B) are both 90° or less. Having angles of 90° or less can improve the structural efficiency of the fused portion. The angles of the two bent portions are preferably less than 90°, and more preferably 80° or less. Furthermore, from the viewpoint of preventing the occurrence of tearing of the laminate film due to stress concentration, the angles of the two bent portions are preferably 50° or more, more preferably 60° or more, and even more preferably 70° or more.

[0017] Height of fused part The height of the fused portion, that is, the height of the fused portion in the thickness direction of the electrode body (for example, the direction of arrow Y in FIG. 1) (for example, in laminated battery 10 shown in FIG. 1, this is height d1 at fused portion 40) is preferably equal to or less than the thickness of the portion of the laminated battery that has the electrode body (for example, height d2 in laminated battery 10 shown in FIG. 1). Having the height of the fused portion equal to or less than the thickness of the portion that has the electrode body can improve the structural efficiency of the battery.

[0018] Width of fused part The width of the fused portion will now be described. The width of the fused portion refers to the length from the end of the portion of the laminated battery having the electrode body to the end of the fused portion of the laminated film in the direction toward the side where the fused portion of the laminated film is formed when viewed from the electrode body side of the laminated battery (for example, the direction of arrow X in FIG. 1) (for example, in the laminated battery 10 shown in FIG. 1, it is the width c of the fused portion 40). From the viewpoint of improving the structural efficiency of the battery, the width of the fused portion is preferably 0.5 mm or more and 2.0 mm or less, and more preferably 0.8 mm or more and 1.5 mm or less.

[0019] <Laminated battery manufacturing method> Next, a method for manufacturing a laminated battery according to an embodiment of the present disclosure will be described. A manufacturing method of a laminated battery according to an embodiment of the present disclosure is a method for manufacturing a laminated battery having an electrode body and a laminate film that covers and encapsulates the electrode body, and having a fused portion where the ends of the laminate film are overlapped and the inner surfaces are fused together. The manufacturing method of this laminated battery includes a rolling process in which the fused portion is rolled into a roll from the tip side, and a pressing process in which press members are pressed against the rolled fused portion from at least two directions to bend it into an angular or arc shape at an angle of 90° or less, thereby forming two bent portions.

[0020] Hereinafter, one embodiment of a method for manufacturing a laminated battery according to an embodiment of the present disclosure will be described with reference to the drawings.

[0021] 2, 3, and 5 are schematic cross-sectional views illustrating a step in a method for manufacturing a laminated battery according to an embodiment of the present disclosure, and FIG. 4 is a schematic top view and a schematic cross-sectional view illustrating a rolling step in a method for manufacturing a laminated battery according to an embodiment of the present disclosure. First, as shown in FIG. 2, a laminated battery 10a is prepared, which includes an electrode body 2 and a laminate film 4 that covers and encapsulates the electrode body 2, and has a fused portion 40a where the ends of the laminate film 4 are overlapped and fused on the inner surface, and in which no bent portion or rolled portion is formed in the fused portion 40a.

[0022] Rolling process Next, the fused portion 40a of the laminated battery 10a is subjected to a rolling process to produce a laminated battery 10b having a fused portion 40cc rolled from the tip end side as shown in FIG.

[0023] An example of the rolling process will now be described in detail with reference to FIG. 4. FIG. 4 is a schematic top view (left side of FIG. 4) and a schematic cross-sectional view (right side of FIG. 4) illustrating the rolling process in the manufacturing method of a laminated battery according to an embodiment of the present disclosure. View A of the schematic cross-sectional view (right side of FIG. 4) is a cross-sectional view showing the AA cross section in the schematic top view (left side of FIG. 4). Similarly, View B of the schematic cross-sectional view is a view showing the BB cross section in the schematic top view, View C of the schematic cross-sectional view is a view showing the CC cross section in the schematic top view, View D of the schematic cross-sectional view is a view showing the DD cross section in the schematic top view, View E of the schematic cross-sectional view is a view showing the EE cross section in the schematic top view, and View F of the schematic cross-sectional view is a view showing the FF cross section in the schematic top view.

[0024] In the method of forming the roll portion shown in Figure 4, a laminated battery 10a without bent or rolled portions is moved in the direction of arrow e, while a roll portion forming member 64, which is arranged at an angle with respect to the direction of arrow e, is pressed against the fused portion 40a, thereby forming a fused portion 40cc rolled into a roll. The roll-section-forming member 64 is disposed at an angle relative to the direction of arrow e, and its inner surface 64a is circular. The end 64in of the roll-section-forming member 64, on the side (i.e., the entrance side) into which the fused portion 40a of the laminated battery 10a moving in the direction of arrow e enters, is positioned so that the leading end 40ad of the fused portion 40a does not come into contact with the roll-section-forming member 64, as shown at position AA in the schematic top view (left side of FIG. 4) and in Figure A in the schematic cross-sectional view (right side of FIG. 4). As the laminated battery 10a subsequently moves in the direction of arrow e, the leading end 40ad of the fused portion 40a comes into contact with the inner surface 64a of the roll-section-forming member 64, and the fused portion 40a begins to deform into a roll, as shown at position BB in the schematic top view (left side of FIG. 4) and in Figure B in the schematic cross-sectional view (right side of FIG. 4). A shaft center 62 is disposed at a position facing the inner surface 64a of the roll portion-forming member 64 across the fused portion 40a to assist the fused portion 40a in starting to deform into a roll shape. The provision of the shaft center 62 guides the fused portion 40a into the gap between the shaft center 62 and the inner surface 64a of the roll portion-forming member 64, facilitating the fused portion 40a to deform into a roll shape. The shaft center 62 may be disposed at a location where the fused portion 40a starts to deform into a roll shape. In FIG. 4, the shaft center 62 is disposed at positions AA and BB in the schematic top view (left side of FIG. 4) and at positions A and B in the schematic cross-sectional view (right side of FIG. 4). However, the shaft center 62 is not disposed at subsequent positions, i.e., positions CC, DD, EE, and FF in the schematic top view (left side of FIG. 4) and positions C, D, E, and F in the schematic cross-sectional view (right side of FIG. 4).

[0025] The fused portion 40a that has begun to deform into a roll shape is then deformed into a shape closer to a circle along the circular inner surface 64a of the roll portion-forming member 64 as the laminated battery 10a moves in the direction of arrow e, as shown in positions CC, DD, EE, and FF in the schematic top view (left side of FIG. 4) of FIG. 4 and in Figures C, D, E, and F in the schematic cross-sectional views (right side of FIG. 4). Then, as the laminated battery 10a moves in the direction of arrow e, the entire fused portion 40a passes through the outlet end 64out of the roll portion-forming member 64, resulting in a laminated battery 10b having a fused portion 40cc rolled into a roll from the tip side, as shown in FIG. 3.

[0026] 4 shows a method for forming a rolled fused portion 40cc by pressing a tilted roll-forming member 64 against the fused portion 40a while moving the laminated battery 10a in the direction of arrow e. However, the rolling process in the embodiments of the present disclosure is not particularly limited as long as it is a process that can roll the fused portion from the tip end into a roll. For example, the fused portion can be rolled from the tip end into a roll by wrapping the fused portion around the shaft center at the tip end and then rolling the fused portion around the shaft center toward the base end of the fused portion (i.e., the end of the fused portion where the electrodes are located).

[0027] Pressing process Next, the laminated battery 10b having a fused portion of 40 cc rolled from the tip end in the rolling process is subjected to a pressing process to produce the laminated battery 10 shown in FIG.

[0028] FIG. 5 is a schematic cross-sectional view illustrating a pressing step in a method for manufacturing a laminated battery according to an embodiment of the present disclosure. In the pressing process shown in FIG. 5, press members 82, 84, and 86 press (preferably heat press) the fused portion 40 cc, which has been rolled from the tip end, from three directions. Specifically, press member 82 presses from below in FIG. 5, press member 84 presses from the right side, and press member 86 presses from above to press (preferably heat press) the fused portion 40 cc, forming two bent portions 40A and 40B bent into an angular or arc shape at angles of 90° or less. Note that the surface of press member 84 pressed from the right side in FIG. 5 against the fused portion 40 cc is inclined so that the angle of bent portion 40A is less than 90° (more preferably 80° or less). Similarly, the surface of press member 86 pressed from above in FIG. 5 against the fused portion 40 cc is inclined so that the angle of bent portion 40B is less than 90° (more preferably 80° or less).

[0029] 5 illustrates a pressing process in which press members are pressed against the rolled fused portion from three directions to form two bent portions. However, the pressing process in the embodiments of the present disclosure is not particularly limited as long as it is a process that can form two bent portions bent into an angular or arc shape at an angle of 90° or less. For example, two bent portions can be formed by pressing press members from two directions. Specifically, two bent portions can be formed by pressing using press member 84 pressed from the right side in FIG. 5 and press member 86 pressed from above, without using press member 82 pressed from below.

[0030] According to the manufacturing method of a laminated battery according to an embodiment of the present disclosure, which includes a rolling step and a pressing step, it is possible to improve the structural efficiency of the fused portion while suppressing the occurrence of tears in the laminate film.

[0031] Conventionally, when forming two bends in the fused part of a laminate film, a bending member (e.g., a roll member) is pressed against both sides of the laminate film, and the bends are formed using the bending member pressed against the inside as a fulcrum. However, stress can concentrate at this fulcrum, causing tears in the laminate film. In contrast, in a manufacturing method of a laminated battery according to an embodiment of the present disclosure, the fused portion is rolled from the leading end into a roll shape in a rolling process, and then press members are pressed against the rolled fused portion from at least two directions to form two bent portions bent into an angular or arc shape at angles of 90° or less. Therefore, as shown in FIG. 5 , the two bent portions can be formed without pressing a bending member (e.g., a roll member) that serves as a fulcrum against the inside of the laminate film. Therefore, stress concentration at the fulcrum does not occur, and tearing of the laminate film can be suppressed. Furthermore, by rolling the leading end of the fused portion into a roll shape, the structural efficiency of the fused portion can be improved. As a result, it is presumed that the embodiment of the present disclosure can improve the structural efficiency of the fused portion while suppressing the occurrence of tears in the laminate film.

[0032] (Battery components) Next, the electrode body and laminate film that constitute the laminate battery according to this embodiment will be described.

[0033] (1) Laminate film The laminate film may have a structure including, for example, a metal layer and a protective resin layer on the outside of the metal layer. The laminate film may also have a three-layer structure including a fusion resin layer on the inside of the metal layer.

[0034] Examples of materials for the fusion resin layer include olefin resins such as polypropylene (PP) and polyethylene (PE). Examples of materials for the metal layer include aluminum, aluminum alloys, and stainless steel. Examples of materials for the protective resin layer include polyethylene terephthalate (PET) and nylon. The thickness of the fusion resin layer is, for example, 40 μm or more and 100 μm or less. The thickness of the metal layer is, for example, 30 μm or more and 60 μm or less. The thickness of the protective resin layer is, for example, 20 μm or more and 60 μm or less. The thickness of the entire laminate film is, for example, 70 μm or more and 220 μm or less.

[0035] (2) Electrode body The electrode assembly functions as a power generating element of the battery. The electrode assembly typically has a positive electrode current collector, a positive electrode active material layer, an electrolyte layer, a negative electrode active material layer, and a negative electrode current collector, in this order in the thickness direction.

[0036] The positive electrode active material layer contains at least a positive electrode active material. The positive electrode active material layer may further contain at least one of a conductive material, an electrolyte, and a binder. The positive electrode active material is, for example, in the form of particles. Examples of the positive electrode active material include oxide active materials. Sulfur (S) may also be used as the positive electrode active material.

[0037] The positive electrode active material preferably contains a lithium composite oxide. The lithium composite oxide may contain at least one element selected from the group consisting of F, Cl, N, S, Br, and I. The lithium composite oxide may have a crystal structure belonging to at least one space group selected from the space groups R-3m, Immm, and P63-mmc (also referred to as P63mc or P6 / mmc). The lithium composite oxide may have an O2-type structure in which the transition metal, oxygen, and lithium are primarily arranged.

[0038] Examples of lithium composite oxides having a crystal structure belonging to R-3m include Li x Me y O α X β(Me represents at least one selected from the group consisting of Mn, Co, Ni, Fe, Al, Cu, V, Nb, Mo, Ti, Cr, Zr, Zn, Na, K, Ca, Mg, Pt, Au, Ag, Ru, W, B, Si, and P, and X represents at least one selected from the group consisting of F, Cl, N, S, Br, and I, and satisfy the conditions 0.5≦x≦1.5, 0.5≦y≦1.0, 1≦α<2, and 0<β≦1.)

[0039] Examples of lithium composite oxides having a crystal structure belonging to Immm include Li x1 M 1 A 1 2(1.5≦x1≦2.3, M 1 contains at least one selected from the group consisting of Ni, Co, Mn, Cu and Fe, and A 1 contains at least oxygen, and A 1 The ratio of oxygen in the oxide is 85 atomic % or more. x1 M 1A 1-x2 M 1B x2 O 2-y A 2 y (0≦x2≦0.5, 0≦y≦0.3, and at least one of x2 and y is not 0, M 1A represents at least one selected from the group consisting of Ni, Co, Mn, Cu, and Fe, and M 1B represents at least one selected from the group consisting of Al, Mg, Sc, Ti, Cr, V, Zn, Ga, Zr, Mo, Nb, Ta and W, and A2 represents at least one selected from the group consisting of F, Cl, Br, S and P.

[0040] Examples of lithium composite oxides having a crystal structure belonging to P63-mmc include M1 x M2 yO2 (where M1 represents an alkali metal (at least one of Na and K is preferred), M2 represents a transition metal (at least one selected from the group consisting of Mn, Ni, Co, and Fe is preferred), and x + y satisfies 0 < x + y ≤ 2). Examples include composite oxides represented by this formula.

[0041] As the lithium composite oxide having an O2-type structure, for example, Li x [Li α (Mn a Co b M c ) 1-α O2 (0.5 < x < 1.1, 0.1 < α < 0.33, 0.17 < a < 0.93, 0.03 < b < 0.50, 0.04 < c < 0.33, and M represents at least one selected from the group consisting of Ni, Mg, Ti, Fe, Sn, Zr, Nb, Mo, W, and Bi). Examples of such composite oxides include Li 0.744 [Li 0.145 Mn 0.625 Co 0.115 Ni 0.115 O2 and the like.

[0042] In addition, the positive electrode preferably contains a solid electrolyte selected from the group of solid electrolytes consisting of sulfide solid electrolytes, oxide solid electrolytes, and halide solid electrolytes in addition to the positive electrode active material. A more preferred embodiment is one in which at least a part of the surface of the positive electrode active material is coated with a sulfide solid electrolyte, an oxide solid electrolyte, or a halide solid electrolyte. As the halide solid electrolyte for coating at least a part of the surface of the positive electrode active material, Li 6-(4-x)b (Ti 1-x Al x ) b F6 (0 < x < 1, 0 < b ≤ 1.5) [LTAF electrolyte] is preferred.

[0043] Examples of conductive materials include carbon materials. The electrolyte may be a solid electrolyte or a liquid electrolyte. The solid electrolyte may be an organic solid electrolyte such as a gel electrolyte, or an inorganic solid electrolyte such as an oxide solid electrolyte or a sulfide solid electrolyte. The liquid electrolyte (electrolytic solution) contains, for example, a supporting salt such as LiPF6 and a solvent such as a carbonate-based solvent. Examples of binders include rubber-based binders and fluoride-based binders.

[0044] The negative electrode active material layer contains at least a negative electrode active material. The negative electrode active material layer may further contain at least one of a conductive material, an electrolyte, and a binder. Examples of the negative electrode active material include metal active materials such as Li and Si, carbon active materials such as graphite, and Li4Ti5O 12 The negative electrode current collector may be in the form of, for example, a foil or a mesh. The conductive material, electrolyte, and binder are the same as those described above.

[0045] The electrolyte layer is disposed between the positive electrode active material layer and the negative electrode active material layer and contains at least an electrolyte. The electrolyte may be a solid electrolyte or a liquid electrolyte. The electrolyte layer is preferably a solid electrolyte layer. The electrolyte layer may have a separator.

[0046] The solid electrolyte preferably contains at least one solid electrolyte species selected from the group consisting of sulfide solid electrolytes, oxide solid electrolytes, and halide solid electrolytes.

[0047] As a sulfide solid electrolyte, it is preferable to contain sulfur (S) as the main component of the anion element, and further, for example, it is preferable to contain Li element, A element, and S element. The A element is at least one selected from the group consisting of P, As, Sb, Si, Ge, Sn, B, Al, Ga, and In. The sulfide solid electrolyte may further contain at least one of O and halogen elements. Examples of the halogen element (X) include F, Cl, Br, I, etc. The composition of the sulfide solid electrolyte is not particularly limited, and examples include xLi2S·(100 - x)P2S5 (70 ≤ x ≤ 80), yLiI·zLiBr·(100 - y - z)(xLi2S·(1 - x)P2S5) (0.7 ≤ x ≤ 0.8, 0 ≤ y ≤ 30, 0 ≤ z ≤ 30). The sulfide solid electrolyte may have a composition represented by the following general formula (1). Li 4-x Ge 1-x P x S4(0 < x < 1) ··· Formula (1) In Formula (1), at least a part of Ge may be substituted with at least one selected from the group consisting of Sb, Si, Sn, B, Al, Ga, In, Ti, Zr, V, and Nb. Also, at least a part of P may be substituted with at least one selected from the group consisting of Sb, Si, Sn, B, Al, Ga, In, Ti, Zr, V, and Nb. A part of Li may be substituted with at least one selected from the group consisting of Na, K, Mg, Ca, and Zn. A part of S may be substituted with a halogen. The halogen is at least one of F, Cl, Br, and I.

[0048] As an oxide solid electrolyte, it is preferable to contain oxygen (O) as the main component of the anion element. For example, it may contain Li, Q element (Q represents at least one of Nb, B, Al, Si, P, Ti, Zr, Mo, W, and S), and O. Examples of the oxide solid electrolyte include garnet-type solid electrolyte, perovskite-type solid electrolyte, NASICON-type solid electrolyte, Li-P-O-based solid electrolyte, Li-B-O-based solid electrolyte, etc. Examples of the garnet-type solid electrolyte include, for example, Li7La3Zr2O 12 、Li 7-x La3(Zr2-x Nb x )O 12 (0≦x≦2), Li5La3Nb2O 12 etc. Examples of perovskite-type solid electrolytes include (Li, La)TiO3, (Li, La)NbO3, (Li, Sr)(Ta, Zr)O3, etc. Examples of NASICON-type solid electrolytes include Li(Al, Ti)(PO4)3, Li(Al, Ga)(PO4)3, etc. Examples of Li-P-O-based solid electrolytes include Li3PO4, LIPON (a compound in which part of the O in Li3PO4 is replaced by N), and examples of Li-B-O-based solid electrolytes include Li3BO3, a compound in which part of the O in Li3BO3 is replaced by C, etc.

[0049] As the halide solid electrolyte, a solid electrolyte containing Li, M, and X (M represents at least one of Ti, Al, and Y, and X represents F, Cl, or Br) is suitable. Specifically, Li 6-3z Y z X6 (X represents Cl or Br, and z satisfies 0 < z < 2), Li 6-(4-x)b (Ti 1-x Al x ) b F6 (0 < x < 1, 0 < b ≦ 1.5) is preferred. Among Li 6-3z Y z X6, Li3YX6 (X represents Cl or Br) is more preferred in terms of excellent lithium ion conductivity, and further Li3YCl6 is preferred. Also, Li 6-(4-x)b (Ti 1-x Al x ) b F6 (0 < x < 1, 0 < b ≦ 1.5) is preferably included together with a solid electrolyte such as a sulfide solid electrolyte from the viewpoint of suppressing oxidative decomposition of the sulfide solid electrolyte, etc.

[0050] The positive electrode current collector collects current from the positive electrode active material layer. Examples of the positive electrode current collector include stainless steel, aluminum, nickel, iron, titanium, and carbon, and aluminum alloy foil or aluminum foil is preferred. Aluminum alloy foil and aluminum foil may be manufactured using powder. The positive electrode current collector may have a foil or mesh shape, for example.

[0051] The negative electrode current collector collects current from the negative electrode active material layer. Examples of the material for the negative electrode current collector include metals such as copper, SUS, and nickel. Examples of the shape of the negative electrode current collector include foil and mesh.

[0052] ·Battery structure The structure of a solid-state battery is a laminated structure of a positive electrode, a solid electrolyte layer, and a negative electrode. The solid-state battery includes so-called all-solid-state batteries that use a solid electrolyte as the electrolyte, and the solid electrolyte may contain an electrolytic solution in an amount of less than 10 mass % relative to the total amount of the electrolyte. The solid electrolyte may also be a composite solid electrolyte containing an inorganic solid electrolyte and a polymer electrolyte.

[0053] The positive electrode has a positive electrode active material layer and a current collector, and the negative electrode has a negative electrode active material layer and a current collector. The solid electrolyte layer may have a single layer structure or a multi-layer structure of two or more layers. The solid-state battery may have, for example, a cross-sectional structure shown in FIG. 6, and the solid electrolyte layer B may have a two-layer structure as shown in FIG. 6. FIG. 6 is a schematic cross-sectional view showing an example of a solid-state battery. The solid-state battery shown in FIG. 6 has a negative electrode including a negative electrode current collector 113 and a negative electrode active material layer A, a solid electrolyte layer B, and a positive electrode including a positive electrode current collector 115 and a positive electrode active material layer C. The negative electrode active material layer A includes a negative electrode active material 101, a conductive additive 105, and a binder 109. The positive electrode active material layer C includes a coated positive electrode active material 103, a conductive additive 107, and a binder 111, and the surface of the coated positive electrode active material 103 is coated with an LTAF electrolyte or a LiNbO electrolyte. The solid-state battery may be configured by sealing the end faces (side faces) of the laminated structure of the positive electrode / solid electrolyte layer / negative electrode with a resin. The current collector of the electrode may have a buffer layer, an elastic layer, or a PTC (Positive Temperature Coefficient) thermistor layer disposed on the surface.

[0054] ·battery The laminated battery in the present disclosure is typically a lithium-ion secondary battery. Examples of uses of the battery include power sources for vehicles such as hybrid electric vehicles (HEVs), plug-in hybrid electric vehicles (PHEVs), electric vehicles (BEVs), gasoline-powered automobiles, and diesel-powered automobiles. It is particularly preferred that the battery be used as a driving power source for hybrid electric vehicles (HEVs), plug-in hybrid electric vehicles (PHEVs), or electric vehicles (BEVs). The battery in the present disclosure may also be used as a power source for mobile objects other than vehicles (e.g., trains, ships, and aircraft), or as a power source for electrical appliances such as information processing devices.

[0055] The present disclosure is not limited to the above-described embodiments. The above-described embodiments are merely examples, and any configuration that is substantially identical to the technical idea described in the claims of the present disclosure and that provides similar effects is included within the technical scope of the present disclosure. [Explanation of symbols]

[0056] 2 electrode body, 4 laminate film, 10, 10a, 10b laminated battery, 40, 40a, 40cc fused portion, 40A, 40B bent portion, 40C roll portion, 40D, 40ad tip, 62 shaft center, 64 roll portion forming member, 82, 84, 86 press member, 101 negative electrode active material, 103 coated positive electrode active material, 105, 107 conductive additive, 109, 111 binder, 113 negative electrode current collector, 115 positive electrode current collector, A negative electrode active material layer, B solid electrolyte layer, C positive electrode active material layer

Claims

1. An electrode body; a laminate film that covers and encapsulates the electrode body, A method for manufacturing a laminated battery having a fused portion in which end portions of the laminate film are overlapped and inner surfaces are fused, a rolling step of rolling the fused portion into a roll from the tip side; a pressing step in which press members are pressed against the rolled fused portion from at least two directions to bend it into an angular or arc shape at an angle of 90° or less, thereby forming two bent portions.

2. 2. The method for manufacturing a laminated battery according to claim 1, wherein the pressing step is a step of pressing the press members from three directions.

Citation Information

Patent Citations

  • Flat battery

    JP2004087431A

  • Battery module, assembled battery, and method of manufacturing the battery module

    JP2011054420A

  • Method for manufacturing battery case

    JP2011258501A

  • Manufacturing method for secondary battery

    JP2019200973A

  • Secondary battery

    WO2018100842A1