Laminated battery and method for manufacturing laminated battery

Abstract

To provide a laminated battery in which deterioration of battery performance due to the intrusion of moisture into an electrode body is suppressed.SOLUTION: A laminated battery includes an electrode body, and a laminate film that covers and encapsulates the electrode body, the laminate film has a structure in which at least a metal layer and a fusion resin layer are laminated inside the metal layer, the laminate film includes a fusion portion where ends of the laminate film are overlapped and the fusion resin layers on the inner surface are fused together, and a metal adhesion portion in part of the fusion portion where the metal layers are in adhesion to each other over the entire longitudinal area of the fusion portion.SELECTED DRAWING: Figure 1

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 laminate type battery in which an electrode body is covered with a laminate film, a fused portion is formed by fusing a part of the laminate film in order to encapsulate 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 an exterior body that has been subjected to a laminated processing, the method comprising the steps of: abutting a pressure plate against a base point for folding the end of the exterior body; 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 forming a folded portion by clamping the end between the pressure plate and the pressing plate, wherein 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, 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] JP 2019-200973 A Summary of the Invention [Problem to be solved by the invention]

[0005] In conventional laminated batteries, the ends of laminate films each having at least a metal layer and a fusion resin layer are overlapped to form a fusion section in which the fusion resin layers on the inner surfaces are fused together. However, moisture can penetrate into the electrode body through the fusion resin layer in the fusion section, which can degrade the battery performance.

[0006] The present disclosure has been made in consideration of the above-described situation, and aims to provide a laminate-type battery in which deterioration of battery performance due to the intrusion of moisture into the electrode body is suppressed, and a method for manufacturing the laminate-type 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 structure in which at least a metal layer and a fusion resin layer are laminated on the inner side of the metal layer, The laminate film has a fused portion where the ends are overlapped and the fusion resin layers on the inner surfaces are fused to each other, a laminated battery, the laminated battery comprising a metal adhesion portion at a portion of the fusion portion, in which the metal layers are in adhesion to each other over the entire area in the longitudinal direction of the fusion portion. <2> The fusion portion has a bent portion bent into an angular or arc shape, and the metal contact portion is disposed in an area other than the bent portion. <1> 2. The laminated battery according to claim 1 . <3> The fusion portion has a plurality of the metal adhesion portions. <1> or <2> 2. The laminated battery according to claim 1 . <4> A method for producing a laminated battery comprising: an electrode assembly; and a laminate film that covers and encapsulates the electrode assembly, the laminate film having a structure in which at least a metal layer and a fusion resin layer are laminated inside the metal layer; and the laminate film has a fusion portion in which ends of the laminate film are overlapped and the fusion resin layers on inner surfaces are fused together, a pressing step of pressing the fused portion with a pressing member and an opposing member from both sides of the fused portion to form a metal adhesion portion in which the metal layers are adhered to each other over the entire longitudinal direction of the fused portion; In the pressing step, at least one of the pressing member and the opposing member is heated to a temperature equal to or higher than the glass transition temperature of the fusion resin layer. <5> The shape of the tip of the pressing member that contacts the fused portion is curved with a radius of curvature R of 0.2 mm or more and 1.68 mm or less, The shape of the tip of the opposing member that contacts the fused portion is smooth. <4> A method for producing the laminated battery according to claim 1. Effect of the Invention

[0008] According to the present disclosure, it is possible to provide a laminated battery in which deterioration of battery performance due to intrusion of moisture into an electrode assembly is suppressed, and a method for manufacturing the laminated battery. [Brief description 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. [Diagram 2] FIG. 2 is a schematic cross-sectional view illustrating a laminated battery having a bent portion at a fused portion according to an embodiment of the present disclosure. [Diagram 3] 1 is a schematic cross-sectional view illustrating a step in a manufacturing method for a laminated battery according to an embodiment of the present disclosure. [Figure 4] FIG. 2 is a schematic cross-sectional view illustrating a pressing step using a pressing roll with a curved tip and an opposing roll with a smooth tip in a manufacturing method for a laminated battery according to an embodiment of the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[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 structure in which at least a metal layer and a fusion resin layer are laminated inside the metal layer, and the laminate film has a fusion portion where the ends of the laminate film are overlapped and the fusion resin layers on the inner surfaces are fused together. A part of the fusion portion has a metal adhesion portion where the metal layers are in contact with each other over the entire area in the longitudinal direction of the fusion portion.

[0011] Hereinafter, one embodiment of a laminate type battery according to the present disclosure will be described with reference to the drawings. The drawings shown below are schematic diagrams, and the size and shape of each part are appropriately exaggerated to make them easier to understand.

[0012] FIG. 1 is a schematic cross-sectional view illustrating a laminate-type battery according to an embodiment of the present disclosure. The laminated battery 10 shown in FIG. 1 has an electrode body 2 and a laminate film 4 that covers and encapsulates the electrode body 2. The laminate film 4 has a structure in which at least a metal layer 42 and a fusion resin layer 44 are laminated on the inside of the metal layer 42. The laminate film 4 may further have a structure in which a protective resin layer is provided on the outside of the metal layer 42. The laminate film 4 has a fusion portion 40 in which the ends of the laminated film 4 are overlapped and the fusion resin layers 44 on the inner surfaces are fused together. A part of the fusion portion 40 has a metal adhesion portion 46 in which the metal layers 42 are in close contact with each other. In the metal adhesion portion 46, the metal layers 42 are in direct contact with each other without the fusion resin layer 44 being interposed therebetween. In the metal adhesion portion 46, the metal layers 42 are in close contact with each other over the entire area of ​​the longitudinal direction of the fusion portion 40 (the depth direction in FIG. 1).

[0013] In conventional laminated batteries, the ends of laminate films each having at least a metal layer and a fusion resin layer are overlapped to form a fusion section in which the fusion resin layers on the inner surfaces are fused together. However, moisture can penetrate into the electrode body through the fusion resin layer in the fusion section, which can degrade the battery performance. In contrast, the laminated battery 10 according to this embodiment has, in a portion of the fused portion 40, a metal adhesion portion 46 in which the metal layers 42 are in close contact with each other over the entire longitudinal area of ​​the fused portion 40. Therefore, the metal adhesion portion 46 prevents moisture from penetrating through the fused resin layer of the fused portion, thereby preventing a decrease in battery performance.

[0014] Number of metal contacts The fusion portion of the laminate film preferably has a plurality of metal adhesive portions (i.e., two or more). Each of the plurality of metal adhesive portions is formed by adhering metal layers to each other over the entire area in the longitudinal direction of the fusion portion. By having a plurality of metal adhesive portions, the deterioration of battery performance due to the intrusion of moisture into the electrode body can be further suppressed.

[0015] Location of metal contacts The laminated battery according to the embodiment of the present disclosure may have a bent portion bent into an angular or arc shape at the fused portion. By having the bent portion, the structural efficiency of the laminated battery can be improved. An example of a laminated battery having a bent portion at a fused portion is shown in Fig. 2. Laminated battery 10B has bent portions 40a and 40b bent into an angular or arc shape at fused portion 40 of laminate film 4. Bent portion 40a is bent at an angle of approximately 90°, and bent portion 40b is bent at an angle of approximately 0°.

[0016] When a bent portion is formed in the fusion portion, it is preferable that the metal adhesion portion is disposed in an area other than the bent portion. By disposing the metal adhesion portion in an area other than the bent portion, the bent portion can be formed into a good shape. For example, in the laminated battery 10B in the embodiment shown in Fig. 2, the metal adhesion portion 46 is disposed between the bent portion 40b and the tip 40c of the fusion portion 40, and is disposed in an area other than the bent portion. In the case where the fusion portion has two bent portions as in the embodiment shown in Fig. 2, it is preferable that the metal adhesion portion is disposed between the base of the fusion portion (i.e., the end portion of the fusion portion 40 on the electrode body 2 side in Fig. 2) and the first bent portion (bent portion 40a in Fig. 2), between the base side and the first bent portion (bent portion 40a in Fig. 2) and the second bent portion (bent portion 40b in Fig. 2), or between the base side and the second bent portion (bent portion 40b in Fig. 2) and the tip of the fusion portion (tip 40c in Fig. 2).

[0017] However, from the viewpoint of ensuring the fusion strength of the fusion part, it is preferable to place the metal adhesion part closer to the tip of the fusion part (tip 40c in FIG. 2). For example, if the fusion part has two bent parts, it is preferable to place the metal adhesion part between the second bent part from the base side (bent part 40b in FIG. 2) and the tip of the fusion part (tip 40c in FIG. 2). On the other hand, if the fusion strength of the fusion part can be ensured, it is preferable to arrange the metal adhesion part closer to the base of the fusion part (the end of the fusion part 40 on the electrode body 2 side in FIG. 2). For example, if the fusion part has two bends, it is preferable to arrange the metal adhesion part between the base of the fusion part (the end of the fusion part 40 on the electrode body 2 side in FIG. 2) and the first bend (bend 40a in FIG. 2), or between the base side and the first bend (bend 40a in FIG. 2) and the second bend (bend 40b in FIG. 2). By arranging the metal adhesion part closer to the base of the fusion part, it is possible to further suppress the intrusion of moisture from the side of the fusion part (the side of the fusion part 40 on the back side and the front side in FIG. 2). In addition, the length of the fusion part may be shortened after arranging the metal adhesion part closer to the base of the fusion part (i.e., the trimming position on the tip side of the fusion part may be closer to the base side of the fusion part).

[0018] <Laminated battery manufacturing method> Next, a method for manufacturing a laminated battery according to an embodiment of the present disclosure will be described.

[0019] A manufacturing method for a laminated battery according to an embodiment of the present disclosure is a manufacturing method for a laminated battery having an electrode body and a laminate film that covers and encapsulates the electrode body, the laminate film having a structure in which at least a metal layer and a fused resin layer are laminated on the inside of the metal layer, and the laminate film has a fused portion where the ends are overlapped and the fused resin layers on the inner surfaces are fused to each other. The method for manufacturing a laminated battery includes a pressing step in which the fused portion is pressed by sandwiching the fused portion from both sides with a pressing member and an opposing member to form a metal adhesion portion in which the metal layers are adhered to each other over the entire longitudinal direction of the fused portion. In this pressing step, at least one of the pressing member and the opposing member (preferably both) is heated to a temperature equal to or higher than the glass transition temperature of the fused resin layer.

[0020] Here, an embodiment of the manufacturing method of the laminated battery according to the present disclosure will be described with reference to the drawings. Fig. 3 is a schematic cross-sectional view illustrating one step in the manufacturing method of the laminated battery according to the embodiment of the present disclosure. The laminated battery shown in Fig. 1 can be obtained by the manufacturing method of the laminated battery shown in Fig. 3.

[0021] 3 has an electrode body 2 and a laminate film 4 that covers and encapsulates the electrode body 2, and the laminate film 4 has a structure in which at least a metal layer 42 and a fusion resin layer 44 are laminated on the inner side of the metal layer 42. The laminate film 4 has a fusion part 40 in which the ends are overlapped and the fusion resin layers 44 on the inner sides are fused together. The manufacturing method of the laminated battery includes a pressing step in which the laminated battery 10 is sandwiched between a pressing roll 6 as a pressing member and an opposing roll 8 as an opposing member from both sides of the fused portion 40 (top and bottom directions in FIG. 3 ) to press the fused portion 40. In the pressing step shown in FIG. 3 , the fused portion 40 in the laminate film 4 of the laminated battery 10 is passed between the pressing roll 6 and the opposing roll 8, which rotate in the forward direction (i.e., rotate in opposite directions) to press the fused portion 40 with the pressing roll 6 and the opposing roll 8. At least one of the pressing roll 6 as a pressing member and the opposing roll 8 as an opposing member (preferably both) is heated to a temperature equal to or higher than the glass transition temperature of the resin constituting the fused resin layer 44. This pressing process melts the resin constituting the fused resin layer 44 of the fused part 40, and the resin with increased fluidity is pushed aside by the pressure from the pressing roll 6 and the opposing roll 8, so that the metal layers 42 come into direct contact with each other. As a result, a metal adhesion part in which the metal layers 42 are adhered to each other is formed over the entire area of ​​the fused part 40 in the longitudinal direction (depth direction in FIG. 3).

[0022] The direction in which the pressing member (e.g., a pressing roll) and the opposing member (e.g., an opposing roll) are pressed against the fused portion of the laminate film may be the opposite to that in FIG. 3, that is, the pressing member may be pressed from below in FIG. 3 and the opposing member may be pressed from above.

[0023] Press temperature In the pressing step, at least one of the pressing member and the opposing member (preferably both) is heated to a temperature equal to or higher than the glass transition temperature of the resin constituting the fusion resin layer. This heating temperature is preferably equal to or lower than the melting point of the material constituting the layers other than the fusion resin layer in the laminate film (e.g., the material constituting the metal layer and the protective resin layer, etc.). The heating temperature in the pressing step is preferably, for example, 120°C or higher and 220°C or lower, and more preferably 160°C or higher and 220°C or lower from the viewpoint of instantaneously melting the resin constituting the fusion resin layer.

[0024] ·clearance The clearance between the pressing member and the opposing member in the pressing process (the shortest distance where the pressing member and the opposing member face each other) is preferably equal to or greater than the total thickness of the metal layers in the laminate film constituting the fused portion. When the thicknesses of the metal layers in the laminate films overlapped in the fused portion are equal, the total thickness of the metal layers is twice the thickness of the metal layers. By making the clearance equal to or greater than the total thickness of the metal layers in the fused portion, it is possible to suppress a reduction in the thickness of the metal layers.

[0025] Furthermore, when the laminate film further has a protective resin layer on the outside of the metal layer 42, the clearance between the pressing member and the opposing member is preferably equal to or less than the total thickness of the metal layer and the protective resin layer in the laminate film constituting the fused portion. When the thicknesses of the metal layer and the protective resin layer in the laminate films overlapped in the fused portion are equal, the total thickness of the metal layer and the protective resin layer is twice the sum of the thickness of the metal layer and the thickness of the protective resin layer. By having the clearance equal to or less than the total thickness of the metal layer and the protective resin layer in the fused portion, the fused portion can be pressed well, and as a result, the metal adhesion portion can be well formed.

[0026] Here, the thickness of the metal layer and the thickness of the protective resin layer refer to the average thickness of one metal layer and one protective resin layer at the location where the laminate film is pressed. The average thickness is determined by arbitrarily selecting five locations from the locations where the laminate film is pressed, measuring the thickness of the metal layer or protective resin layer, and taking the arithmetic average value of each thickness at the five locations. The total thickness of the metal layer refers to the sum of the average thickness of the metal layer in one laminate film and the average thickness of the metal layer in the other laminate film at the location where the fusion part where the ends are overlapped is pressed. The total thickness of the metal layer and the protective resin layer refers to the sum of the average thickness of the metal layer and the protective resin layer in one laminate film and the average thickness of the metal layer and the protective resin layer in the other laminate film at the location where the fusion part is pressed.

[0027] - Shape of the tip of the pressing member and the opposing member The shape of the tip of the opposing member (e.g., opposing roll) that contacts the fused portion is preferably smooth or V-shaped. When the tip of the opposing member is smooth, the amount of deformation of the laminate film at the metal adhesion portion is suppressed, and as a result, the influence on the foldability when forming a bent portion at the fused portion of the laminate film can be suppressed. When the tip of the opposing member is V-shaped, the adhesion between the metal layers at the metal adhesion portion can be further improved. It is more preferable that the tip of the opposing member is smooth in terms of the influence on the foldability when forming a bent portion at the fused portion.

[0028] On the other hand, the shape of the tip of the pressing member (e.g., a pressing roll) that comes into contact with the fused portion is preferably curved from the viewpoint of preventing tearing of the metal layer in the laminate film (and the protective resin layer, if any). Here, a diagram illustrating a pressing process using a pressing roll with a curved tip and an opposing roll with a smooth tip is shown in FIG. 4. In FIG. 4, the pressing roll 6 is pressed against the opposing roll 8 from below against a fusion part having metal layers 42A and 42B and fusion resin 44A formed by melting and fusing fusion resin layers together, based on the information in FIG. 4, to form a metal adhesive part. The resin of fusion resin 44A melts due to the heat and pressure from the pressing roll 6 and the opposing roll 8, and is pushed aside toward the tip side and base side of the fusion part (left and right direction in FIG. 4). Therefore, a raised part 48 is formed around the metal adhesive part by the pushed-aside resin. Therefore, in a pressing member (e.g., a pressing roll) with a curved tip, it is preferable that the tip curvature radius R is 1.68 mm or less. By setting the tip curvature radius R in this range, the amount of fusion resin pushed aside is not too large, and the raised portion (raised portion 48 in FIG. 4) formed around the metal adhesion portion does not become too large, thereby suppressing the effect on the foldability when forming a bent portion in the fusion portion of the laminate film.

[0029] The reason why the radius of curvature R of the curved tip of the pressing member is preferably 1.68 mm or less will be described with reference to FIG. The condition for suppressing the effect on foldability when forming a bent portion in the fused portion of the laminate film is assumed to be as shown in the following formula (1). Note that X in formula (1) represents the length X of the part recessed by pressing with the pressing roll 6 at the height of the surface of the metal layer 42A before pressing. Formula (1) X≦L1 / 2 Here, L1 represents the distance from the tip of the fused portion of the laminate film to the point where the bent portion is formed. The value of X is expressed by the following formula (2). Equation (2) X=2√(R 2 -(R-2t3) 2 ) Here, R represents the radius of curvature of the tip of the pressing member, and t3 represents the average thickness of one metal layer at the location where the laminate film is pressed. 1 / 2 " represents. The following equation (3) is derived from equations (1) and (2). Equation (3) R≦(L1 2 ) / (64t3)-t3 Furthermore, when the general values ​​of L1 = 3 mm and t3 = 0.08 mm are applied to L1 and t3, the following formula (4) is derived. Formula (4) R≦1.68

[0030] From the above, in order to suppress the influence on the foldability when forming a bent portion in the fused portion of the laminate film, it is preferable that the radius of curvature R of the tip of a curved pressing member (for example, a pressing roll) is 1.68 mm or less.

[0031] On the other hand, the lower limit of the radius of curvature R of the tip of a pressing member (e.g., a pressing roll) having a curved tip is preferably 0.2 mm or more, from the viewpoint of preventing tearing of the metal layer in the laminate film (and the protective resin layer if further provided). In view of the above, it is preferable that the radius of curvature R of the tip of the pressing member is 0.2 mm or more and 1.68 mm or less.

[0032] The length of the region where the metal layers are in contact with each other in the metal contact portion (the length in the direction perpendicular to the longitudinal direction and thickness direction of the fusion portion (length a in the left-right direction in Figure 4)) is preferably 50 μm or more and 300 μm or less, and more preferably 80 μm or more and 200 μm or less. By setting the length of the region where the metal layers are in close contact with each other to be equal to or less than the upper limit, the amount of fusion resin pushed aside is not too large, and the influence on the foldability when forming a bent portion in the fusion portion of the laminate film can be suppressed. By setting the length of the region where the metal layers are in close contact with each other to be equal to or more than the lower limit, the intrusion of moisture into the electrode body can be more effectively suppressed.

[0033] The height of the raised portion (raised portion 48 in FIG. 4) formed around the metal contact portion is preferably 150 μm or less, and more preferably 100 μm or less. The lower the height of the raised portion, the more preferable. When the height of the raised portion is equal to or less than the above upper limit, the influence on the foldability when forming a bent portion in the fused portion of the laminate film can be suppressed. The height of the raised portion refers to the average distance (height b in FIG. 4) from the surface of the metal layer in the area where the metal adhesion area and the raised portion are not formed (the surface of metal layer 42A in FIG. 4) to the apex of the raised portion. The average height of the raised portion is calculated by selecting five areas where the raised portion is formed, measuring the height of the raised portion, and calculating the arithmetic average value of the heights at the five areas.

[0034] (Battery components) Next, the electrode body and laminate film constituting the laminate type battery according to this embodiment will be described.

[0035] (1) Laminate film The laminate film has at least a metal layer and a protective resin layer on the outer side of the metal layer. The laminate film may be a three-layer film further having a fusion resin layer on the inner side of the metal layer.

[0036] 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.

[0037] (2) Electrode body The electrode assembly functions as a power generating element of the battery. The electrode assembly usually 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.

[0038] 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.

[0039] The positive electrode active material preferably contains a lithium composite oxide. The lithium composite oxide may contain at least one 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 called P63mc or P6 / mmc). The lithium composite oxide may have an O2 type structure in which the transition metal, oxygen, and lithium are mainly arranged.

[0040] 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 satisfies 0.5≦x≦1.5, 0.5≦y≦1.0, 1≦α<2, and 0<β≦1.)

[0041] 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.

[0042] Examples of lithium composite oxides having a crystal structure belonging to P63-mmc include M1 x M2y O2 (where M1 represents an alkali metal (preferably at least one of Na and K), M2 represents a transition metal (preferably at least one selected from the group consisting of Mn, Ni, Co, and Fe), and 0 < x + y ≦ 2 is satisfied.) Examples include composite oxides represented by this formula.

[0043] 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 (where 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 composite oxides represented by this formula include Li 0.744 [Li 0.145 Mn 0.625 Co 0.115 Ni 0.115 O2 and the like.

[0044] 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, and a mode 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 is more preferable. 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 preferable.

[0045] Examples of the conductive material 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 the binder include a rubber-based binder and a fluoride-based binder.

[0046] 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, Li4Ti5O 12 The oxide active material may be, for example, a foil or mesh. The conductive material, electrolyte, and binder are the same as those described above.

[0047] 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.

[0048] The solid electrolyte preferably contains at least one solid electrolyte species selected from the group of solid electrolytes consisting of sulfide solid electrolytes, oxide solid electrolytes, and halide solid electrolytes.

[0049] The positive electrode current collector collects the current of 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 preferable. The aluminum alloy foil and aluminum foil may be manufactured using powder. The shape of the positive electrode current collector is, for example, a foil shape or a mesh shape.

[0050] 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 a foil shape and a mesh shape.

[0051] ·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 vehicles, and diesel-powered vehicles. In particular, the battery is preferably 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 moving objects other than vehicles (e.g., railways, ships, and aircraft), and may also be used as a power source for electrical appliances such as information processing devices.

[0052] The present disclosure is not limited to the above-described embodiments. The above-described embodiments are merely examples, and anything that has substantially the same configuration as the technical idea described in the claims of the present disclosure and exhibits similar effects is included in the technical scope of the present disclosure. [Explanation of symbols]

[0053] 2 electrode body, 4 laminate film, 6 pressing roll, 8 opposing roll, 10, 10B laminated battery, 40 fusion portion, 40a, 40b bent portion, 40c tip, 42, 42A, 42B metal layer, 44 fusion resin layer, 44A fusion resin, 46 metal contact portion, 48 raised portion

Claims

1. An electrode body; A laminate film that covers and encapsulates the electrode body, The laminate film has a structure in which at least a metal layer and a fusion resin layer are laminated on the inner side of the metal layer, The laminate film has a fused portion where the ends are overlapped and the fusion resin layers on the inner surfaces are fused to each other, a laminated battery, the laminated battery comprising a metal adhesion portion at a portion of the fusion portion, in which the metal layers are in adhesion to each other over the entire area in the longitudinal direction of the fusion portion.

2. 2. The laminated battery according to claim 1, wherein the fusion portion has a bent portion bent into an angular or arc shape, and the metal contact portion is disposed in an area other than the bent portion.

3. The laminate type battery according to claim 1 or 2, wherein the fusion portion has a plurality of the metal contact portions.

4. A method for producing a laminated battery comprising: an electrode assembly; and a laminate film that covers and encapsulates the electrode assembly, the laminate film having a structure in which at least a metal layer and a fusion resin layer are laminated inside the metal layer; and the laminate film has a fusion portion in which ends of the laminate film are overlapped and the fusion resin layers on inner surfaces are fused together, a pressing step of pressing the fused portion with a pressing member and an opposing member from both sides of the fused portion to form a metal adhesion portion in which the metal layers are adhered to each other over the entire longitudinal direction of the fused portion; In the pressing step, at least one of the pressing member and the opposing member is heated to a temperature equal to or higher than the glass transition temperature of the fusion resin layer.

5. The shape of the tip of the pressing member that contacts the fused portion is curved with a radius of curvature R of 0.2 mm or more and 1.68 mm or less, The method for producing a laminated battery according to claim 4 , wherein a tip of the opposing member that contacts the fused portion has a smooth shape.

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