Laminated battery and method for manufacturing laminated battery

Abstract

The laminated battery has an electrode body and a laminated film covering and sealing the electrode body, and the laminated film has a welded portion in which end portions overlap each other and inner surfaces are welded. The welded part has two bent parts which are bent in an angular or arcuate shape so as to form an angle of 90 DEG or less, and a roll part which is disposed closer to the tip side of the welded part than the two bent parts and is rolled up in a roll shape.

Description

Technical Field

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

[0002] In a laminated battery in which an electrode body is covered with a laminate film, a portion of the laminate film is welded to form a welded portion in order to seal the electrode body.

[0003] For example, Japanese Patent Publication No. 2019-200973 discloses a method for manufacturing a secondary battery, wherein the secondary battery has a bending portion at at least one end in an outer body that has been laminated, and the manufacturing method comprises: a process of making a pressure plate abut against the base point of the bending at the end of the outer body; and after the abutting process, sliding the pressure plate and a pressure plate arranged at a position opposite to the pressure plate in a manner of clamping the end, bending the end around the base point, and clamping the end with the pressure plate and the pressure plate to form the bending portion, wherein the surface that slides with the end of the pressure plate has an inclined surface for bending the end and a clamping surface for clamping the end, and the inclined surface is inclined in a cross section orthogonal to the width direction of the pressure plate in such a manner that the cross-sectional area of ​​the pressure plate becomes narrower in the sliding direction, and the inclined surface is inclined toward the width direction. Summary of the invention

[0004] Conventionally, in order to save space at the welded portion of the laminated film in a laminated battery and improve the structural efficiency, a portion of the welded portion is bent to form a bent portion. However, stress may concentrate on the bent portion, causing cracks in the laminated film.

[0005] The present disclosure has been made in view of the above-mentioned actual situation, and an object of the present disclosure is to provide a laminated battery and a method for manufacturing the laminated battery, which can improve the structural efficiency of the welded portion while suppressing cracks in the laminated film.

[0006] <1> A laminated battery having: an electrode body; and a laminate film covering and sealing the electrode body, The laminate film has a welded portion where the ends overlap each other and the inner surfaces are welded together, The weld portion includes two bent portions bent in an angular or arcuate shape to form an angle of 90° or less, and a rolled portion disposed on the front end side of the weld portion relative to the two bent portions and rolled up in a roll shape. <2> according to <1> The laminated battery described herein, wherein The angle of the bent portion is greater than 60°. <3> according to <1> or <2> The laminated battery described herein, wherein The height of the welded 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. <4> A method for manufacturing a laminated battery, the laminated battery comprising: an electrode body; and a laminate film covering and sealing the electrode body, The laminate film has a welded portion where the ends thereof overlap each other and the inner surfaces thereof are welded together. Wherein, the manufacturing method comprises: A rolling step of rolling up the welded portion from the front end side in a roll shape; and In the punching step, a punching member is pressed against the rolled welded portion from at least two directions to bend the welded portion in an angular or arc shape at an angle of 90° or less to form two bent portions. <5> according to <4> The method for producing a laminated battery described herein, wherein: The punching process is a process of pressing the punching member against each other from three directions.

[0007] According to the present disclosure, it is possible to provide a laminated battery and a method for manufacturing the laminated battery, which can improve the structural efficiency of the welded portion while suppressing the occurrence of cracks in the laminated film. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Features, advantages, and technical and industrial significance of exemplary embodiments of the present invention will be described below with reference to the accompanying drawings, in which like reference numerals represent like elements. Figure 1 is a schematic cross-sectional view illustrating a laminated battery according to an embodiment of the present disclosure; Figure 2 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 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 A schematic plan view and a schematic cross-sectional view illustrating a winding step in a method for manufacturing a laminated battery according to an embodiment of the present disclosure; Figure 5 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 This is a schematic cross-sectional view showing an example of a solid-state battery. DETAILED DESCRIPTION Laminated battery

[0009] The laminated battery according to the embodiment of the present disclosure comprises an electrode body and a laminate film covering and sealing the electrode body. The laminate film has a welded portion in which the ends overlap each other and the inner surfaces are welded. Furthermore, the welded portion comprises two bent portions bent in an angular or arc shape at an angle of less than 90°, and a rolled portion arranged at the front end side of the welded portion relative to the two bent portions and rolled up in a roll shape.

[0010] Hereinafter, one embodiment of a laminated battery according to an embodiment of the present disclosure will be described with reference to the drawings. Each of the drawings shown below is schematically shown, and the size and shape of each part are appropriately exaggerated for easy understanding.

[0011] Figure 1 It is a schematic cross-sectional view illustrating a laminated battery according to an embodiment of the present disclosure. Figure 1 The laminated battery 10 shown has an electrode body 2 and a laminate film 4 that covers and seals the electrode body 2. The laminate film 4 has a welded portion 40 whose ends overlap each other and whose inner surfaces are welded. Furthermore, the welded portion 40 has two bent portions 40A and 40B that are bent in an angular or arc shape in a manner that forms an angle of less than 90°, and a roll portion 40C that is arranged at the front end side 40D of the welded portion 40 closer to the two bent portions 40A and 40B and is rolled up in a roll shape. The roll portion 40C is rolled up in a roll shape toward the inner side direction of the welded portion 40 having the two bent portions 40A and 40B (that is, the direction of the side of the two bent portions 40A and 40B that forms an angle of less than 90°). In addition, the roll portion refers to a portion where the curved shape is continuous.

[0012] The laminated battery according to the embodiment of the present disclosure has the above-described configuration, and can suppress the occurrence of cracks in the laminated film while improving the structural efficiency of the welded portion.

[0013] First, the laminated battery according to the embodiment of the present disclosure has a rolled portion at the front end side of the weld portion, so that space can be saved and the structural efficiency of the weld portion can be improved. In addition, the laminated battery has a roll portion at the front end side of the welding portion closer to the two bent portions, so even if the bending angles of the two bent portions are not made extremely acute (for example, a bent portion with an angle of 0°), the structural efficiency can be improved as described above. In a bent portion with an extremely acute angle (for example, an angle of 0°), stress sometimes concentrates on the acute angle and causes the laminate film to rupture. However, in the embodiment of the present disclosure, the structural efficiency can be improved even if the bending angles of the two bent portions are not made extremely acute, so the concentration of stress on the angle can be alleviated, and the rupture of the laminate film can be suppressed.

[0014] As described above, according to the laminated battery according to the embodiment of the present disclosure, it is presumed that the structural efficiency of the welded portion can be improved while suppressing the occurrence of cracks in the laminated film. Angle of bend

[0015] The angles of the two bends (e.g. Figure 1 In the laminated battery 10 shown, the angle a of the bent portion 40A and the angle b of the bent portion 40B are both bent in an angular or arc shape so as to be less than 90°. By making the angle less than 90°, the structural efficiency of the welded portion can be improved. The angles of the two bent portions are more preferably less than 90°, and more preferably less than 80°. Furthermore, from the viewpoint of suppressing cracking of the laminated film due to stress concentration, the angles of both bent portions are preferably 50° or more, more preferably 60° or more, and even more preferably 70° or more. Height of welded part

[0016] The height of the welded portion, that is, the thickness direction of the electrode body (for example Figure 1 The height of the welded portion in the direction of the arrow Y in the middle (for example, Figure 1 In the laminated battery 10 shown in FIG. 1 , the height d1 of the welded portion 40 is preferably equal to the thickness of the portion of the laminated battery having the electrode body (e.g., Figure 1 In the laminated battery 10 shown, the height is less than d2). By making the height of the welded portion less than the thickness of the portion having the electrode body, the structural efficiency of the battery can be improved. Width of welded part

[0017] The width of the weld is described below. The width of the weld refers to the direction of the side where the weld of the laminate film is formed when viewed from the electrode body side in the laminated battery (e.g. Figure 1 The length from the end of the portion having the electrode body in the laminated battery to the end of the welded portion of the laminated film in the direction of the arrow X (for example, in the direction of the arrow X) is Figure 1 In the laminated battery 10 shown, it is the width c of the weld 40. From the viewpoint of improving the structural efficiency of the battery, the width of the weld is preferably 0.5 mm to 2.0 mm, more preferably 0.8 mm to 1.5 mm. Method for manufacturing laminated battery

[0018] Next, a method for manufacturing a laminated battery according to an embodiment of the present disclosure will be described. A method for manufacturing a laminated battery according to an embodiment of the present disclosure is a method for manufacturing a laminated battery including an electrode body and a laminate film covering and sealing the electrode body, and having a welded portion where end portions of the laminate film overlap and the inner surfaces are welded. The manufacturing method of the laminated battery comprises: a rolling process, in which the fusion bonded portion is rolled up from the front end side; and a punching process, in which a punching member is pressed against and punched from at least two directions against the rolled fusion bonded portion to form two bent portions by bending the rolled fusion bonded portion in an angular or arc shape at an angle of less than 90°.

[0019] 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.

[0020] Figure 2 , Figure 3 , Figure 5 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 It is a schematic plan view and a schematic cross-sectional view illustrating a winding step in the method for manufacturing a laminated battery according to the embodiment of the present disclosure. First, if Figure 2 As shown, a laminated battery 10a is prepared, which has an electrode body 2 and a laminate film 4 covering and sealing the electrode body 2, and has a welded portion 40a in which the ends of the laminate film 4 overlap each other and the inner surfaces are welded, and no bent portion or rolled portion is formed in the welded portion 40a. Rolling process

[0021] Next, the welded portion 40a in the laminated battery 10a is subjected to a winding process to produce a laminated battery 10a. Figure 3 The laminated battery 10b shown has a welded portion 40cc rolled up from the front end side.

[0022] Here, use Figure 4 An example of a winding process will be described in detail. Figure 4 2 is a schematic plan view illustrating a winding step in a method for manufacturing a laminated battery according to an embodiment of the present disclosure ( Figure 4 The left side) and the schematic cross-sectional view ( Figure 4 Schematic cross-sectional view ( Figure 4 Figure A in the right side of the figure is a schematic top view ( Figure 4 Similarly, the B figure in the schematic cross-sectional view is a figure showing the BB section in the schematic top view, the C figure in the schematic cross-sectional view is a figure showing the CC section in the schematic top view, the D figure in the schematic cross-sectional view is a figure showing the DD section in the schematic top view, the E figure in the schematic cross-sectional view is a figure showing the EE section in the schematic top view, and the F figure in the schematic cross-sectional view is a figure showing the FF section in the schematic top view.

[0023] exist Figure 4In the roll forming method shown, while the laminated battery 10a without the bent portion and the roll is moved in the direction of arrow e, the roll forming member 64 arranged obliquely relative to the direction of arrow e is pressed against the weld 40a, thereby forming a weld 40cc rolled up in a roll shape. The roll forming member 64 is arranged to be inclined relative to the direction of arrow e, and the inner side surface 64a is rounded. In the roll forming member 64, the end 64in on the side (i.e., the entrance side) where the welded portion 40a of the laminated battery 10a moving in the direction of arrow e enters is as shown in FIG. Figure 4 A schematic top view of Figure 4 AA position and schematic cross-sectional view (left side) Figure 4 As shown in FIG. A on the right side of the figure, it is arranged at a position that does not contact the front end 40ad of the welded portion 40a. Then, as the laminated battery 10a moves in the direction of arrow e, as shown in FIG. Figure 4 A schematic top view of Figure 4 BB position and schematic cross-sectional view ( Figure 4 As shown in FIG. B (on the right side of the figure), the front end 40ad of the weld portion 40a contacts the inner side surface 64a of the roll forming member 64, and the weld portion 40a begins to deform in a roll shape. In addition, at a position opposite to the inner side surface 64a of the roll forming member 64 across the weld portion 40a, an axis 62 for assisting the weld portion 40a in starting to deform in a roll shape is arranged. By providing the axis 62, the weld portion 40a is guided to the gap between the axis 62 and the inner side surface 64a of the roll forming member 64, and the weld portion 40a is easily deformed in a roll shape. The axis 62 only needs to be provided at the location where the weld portion 40a begins to deform in a roll shape. Figure 4 In the schematic top view ( Figure 4 AA position and BB position and a schematic cross-sectional view ( Figure 4 On the other hand, in the position after that, that is, in the schematic top view ( Figure 4 The CC position, DD position, EE position and FF position of the left side of the image, and the schematic cross-sectional view ( Figure 4 In the positions shown in Figures C, D, E and F (on the right side of the figure), the axis 62 is not set.

[0024] The welded portion 40a that begins to deform in a roll shape then moves in the direction of arrow e as the laminated battery 10a moves. Figure 4 A schematic top view of Figure 4 The CC position, DD position, EE position and FF position of the left side of the image, and the schematic cross-sectional view ( Figure 4As shown in Figs. C, D, E and F of the right side of the roll forming member 64, the roll forming member 64 is deformed into a shape closer to a circle along the circular inner side surface 64a. Then, due to the movement of the laminated battery 10a in the direction of arrow e, the welded portion 40a passes through the end portion 64out on the outlet side of the roll forming member 64, thereby obtaining Figure 3 The laminated battery 10b shown has a welded portion 40cc rolled up from the front end side.

[0025] exist Figure 4 , the following method is shown: by moving the laminated battery 10a in the direction of arrow e, the inclined roll forming member 64 is pressed against the welding portion 40a, thereby forming a weld portion 40cc rolled up in a roll. However, the rolling process in the embodiment of the present disclosure is not particularly limited as long as it is a process that can roll up the welding portion from the front end side. For example, by winding the axis around the front end of the welding portion and winding the welding portion toward the root side of the welding portion (that is, the end of the welding portion on the side where the electrode is arranged) with the axis as the center, the welding portion can also be rolled up from the front end side. Stamping process

[0026] Next, the laminated battery 10b having the welded portion 40cc rolled up from the front end side in the rolling step is subjected to a pressing step to produce a Figure 1 A laminated battery 10 is shown.

[0027] Figure 5 It is a schematic cross-sectional view illustrating a pressing step in the method for manufacturing a laminated battery according to an embodiment of the present disclosure. exist Figure 5 In the stamping process shown, the stamping members 82, 84, and 86 are pressed from three directions against the welded portion 40cc rolled up from the front end (preferably hot stamping). Figure 5 The stamping member 84 is pressed from the right side and the stamping member 86 is pressed from the top to form two curved portions 40A and 40B that are bent in an angular or arc shape at an angle of less than 90°. Figure 5 The surface of the punch member 84 that abuts against the welded portion 40cc is inclined so that the angle of the bent portion 40A becomes less than 90° (more preferably less than 80°). Figure 5 The surface of the punch member 86 abutting on the upper side in the middle abutting against the welded portion 40cc is also inclined so that the angle of the bent portion 40B becomes smaller than 90° (more preferably, 80° or less).

[0028] exist Figure 5In the embodiment of the present invention, a stamping process is described in which a stamping member is pressed against a rolled weld portion from three directions to form two bent portions. However, the stamping process in the embodiment of the present invention is not particularly limited as long as it can form two bent portions that are angularly or arcuately bent at an angle of less than 90°. For example, two bent portions can also be formed by pressing a stamping member against two directions. Specifically, Figure 5 The punching member 84 abutting from the right side and the punching member 86 abutting from the top are used to punch and form two bent portions without using the punching member 82 abutting from the bottom.

[0029] According to the method for manufacturing a laminated battery according to the embodiment of the present disclosure including the winding step and the pressing step, it is possible to improve the structural efficiency of the welded portion and suppress the occurrence of cracks in the laminated film.

[0030] In the past, when forming two bends at the welded portion of a laminated film, a bending member (such as a roller member) was pressed against both sides of the laminated film, and the bending member pressed against the inner side was used as a fulcrum to form the bends. However, there were cases where stress concentrated on the fulcrum, causing the laminated film to rupture. In contrast, in the manufacturing method of the laminated battery according to the embodiment of the present disclosure, after the welded portion is rolled up from the front end side in a rolling process, a punching member is pressed against the rolled welded portion from at least two directions to form two bent portions that are angularly or arcuately bent at an angle of less than 90°. Figure 5 As shown, two bends can be formed without the bending member (e.g. roller member) that will serve as a fulcrum being pressed against the inner side of the laminated film. Therefore, stress concentration on the fulcrum will not occur, and the rupture of the laminated film can be suppressed. In addition, by rolling up the front end side of the welded portion in a roll shape, the structural efficiency of the welded portion can be improved. Therefore, according to the embodiment of the present disclosure, it is presumed that the structural efficiency of the welded portion can be improved while suppressing the occurrence of cracks in the laminate film. Battery components

[0031] Next, the electrode body and the laminate film constituting the laminated battery according to the present embodiment will be described. 1.Laminating film

[0032] The laminate film may be, for example, a structure having a metal layer and a protective resin layer outside the metal layer. Alternatively, the laminate film may be a three-layer structure film having a fusion resin layer inside the metal layer.

[0033] As the material of the welding resin layer, for example, olefin resins such as polypropylene (PP) and polyethylene (PE) can be cited. As the material of the metal layer, for example, aluminum, aluminum alloy, and stainless steel can be cited. As the material of the protective resin layer, for example, polyethylene terephthalate (PET) and nylon can be cited. The thickness of the welding resin layer is, for example, greater than 40 μm and less than 100 μm. The thickness of the metal layer is, for example, greater than 30 μm and less than 60 μm. The thickness of the protective resin layer is, for example, greater than 20 μm and less than 60 μm. The thickness of the entire laminated film is, for example, greater than 70 μm and less than 220 μm. 2. Electrode body

[0034] The electrode body functions as a power generation element of the battery and generally 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.

[0035] The positive electrode active material layer contains at least a positive electrode active material. The positive electrode active material layer may also contain at least one of a conductive material, an electrolyte, and a binder. The shape of the positive electrode active material is, for example, a particle. Examples of the positive electrode active material include oxide active materials. In addition, sulfur (S) may also be used as the positive electrode active material.

[0036] As the positive electrode active material, preferably a lithium composite oxide is included. The lithium composite oxide may also contain at least one selected from F, Cl, N, S, Br and I. In addition, the lithium composite oxide may also have a crystal structure belonging to at least one space group selected from space groups R-3m, Immm and P63-mmc (also referred to as P63mc, P6 / mmc). In addition, the lithium composite oxide may also be a transition metal, oxygen and lithium mainly arranged in an O2 type structure.

[0037] 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 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, X represents at least one selected from F, Cl, N, S, Br and I, and satisfies 0.5≤x≤1.5, 0.5≤y≤1.0, 1≤α<2, 0<β≤1) represented by a compound.

[0038] Examples of lithium composite oxides having a crystal structure belonging to Immm include Li x1 M 1 A 1 2(Satisfying 1.5 ≤ x1 ≤ 2.3, M 1 contains at least one selected from Ni, Co, Mn, Cu, and Fe, A 1 contains at least oxygen, and the proportion of oxygen in A 1 is 85 atomic % or more) represents a composite oxide (as a specific example, Li 2 NiO 2 ), Li x1 M 1A 1-x2 M 1B x2 O 2- y A 2 y (0 ≤ x2 ≤ 0.5, 0 ≤ y ≤ 0.3, at least one of x2 and y is not 0, M 1A represents at least one selected from Ni, Co, Mn, Cu, and Fe, M 1B represents at least one selected from Al, Mg, Sc, Ti, Cr, V, Zn, Ga, Zr, Mo, Nb, Ta, and W, A 2 represents at least one selected from F, Cl, Br, S, and P) represents a composite oxide.

[0039] As a lithium composite oxide having a crystal structure belonging to P63 - mmc, for example, M1 x M2 y O 2 (M1 represents an alkali metal (preferably at least one of Na and K), M2 represents a transition metal (preferably at least one selected from Mn, Ni, Co, and Fe), and x + y satisfies 0 < x + y ≤ 2) represents a composite oxide.

[0040] As a lithium composite oxide having an O2 - type structure, for example, Li x [Li α (Mn a Co b M c ) 1-α O 2 (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, M represents at least one selected from Ni, Mg, Ti, Fe, Sn, Zr, Nb, Mo, W, and Bi) represents a composite oxide. As a specific example, Li 0.744 [Li 0.145 Mn 0.625 Co 0.115 Ni 0.115 O 2 etc.

[0041] In addition, the positive electrode preferably contains, in addition to the positive electrode active material, a solid electrolyte selected from the group of solid electrolytes consisting of sulfide solid electrolytes, oxide solid electrolytes, and halide solid electrolytes. More preferably, 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 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 F 6 (0 < x < 1, 0 < b ≤ 1.5) [LTAF electrolyte].

[0042] As the conductive material, for example, a carbon material can be cited. The electrolyte can be either a solid electrolyte or a liquid electrolyte. The solid electrolyte can be either 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. In addition, the liquid electrolyte (electrolyte solution) contains, for example, supporting salts such as LiPF 6 and solvents such as carbonate-based solvents. In addition, as the binder, for example, a rubber-based binder or a fluoride-based binder can be cited.

[0043] The negative electrode active material layer contains at least a negative electrode active material. The negative electrode active material layer may also contain at least one of a conductive material, an electrolyte, and a binder. As the negative electrode active material, for example, metal active materials such as Li and Si, carbon active materials such as graphite, and oxide active materials such as Li 4 Ti 5 O 12 etc. can be cited. The shape of the negative electrode current collector is, for example, foil-shaped or mesh-shaped. Regarding the conductive material, electrolyte, and binder, it is the same as the above content.

[0044] 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 can be either a solid electrolyte or a liquid electrolyte. As the electrolyte layer, a solid electrolyte layer is preferred. The electrolyte layer may also have a spacer.

[0045] As the solid electrolyte, it is preferred to contain at least one solid electrolyte selected from the group of solid electrolytes consisting of sulfide solid electrolytes, oxide solid electrolytes, and halide solid electrolytes.

[0046] As a sulfide solid electrolyte, it preferably contains sulfur (S) as the main component of the anion element, and further preferably contains, for example, Li element, A element and S element. The A element is at least one selected from P, As, Sb, Si, Ge, Sn, B, Al, Ga and In. The sulfide solid electrolyte may also contain at least one of O and halogen element. As the halogen element (X), for example, F, Cl, Br, I, etc. can be cited. The composition of the sulfide solid electrolyte is not particularly limited, and for example, xLi 2 S·(100-x)P 2 S 5 (70≤x≤80), yLiI·zLiBr·(100-y-z)(xLi 2 S·(1-x)P 2 S 5 )(0.7≤x≤0.8, 0≤y≤30, 0≤z≤30). The sulfide solid electrolyte may also have a composition represented by the following general formula (1). Li 4-x Ge 1-x P x S 4 (0<x<1)···Formula (1) In Formula (1), at least a part of Ge can be replaced by at least one selected from Sb, Si, Sn, B, Al, Ga, In, Ti, Zr, V and Nb. In addition, at least a part of P can be replaced by at least one selected from Sb, Si, Sn, B, Al, Ga, In, Ti, Zr, V and Nb. A part of Li can be replaced by at least one selected from Na, K, Mg, Ca and Zn. A part of S can be replaced by a halogen. As the halogen, it is at least one of F, Cl, Br and I.

[0047] As an oxide solid electrolyte, it preferably contains oxygen (O) as the main component of the anion element, and for example, it can contain Li, Q element (Q represents at least one of Nb, B, Al, Si, P, Ti, Zr, Mo, W and S) and O. As the oxide solid electrolyte, 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. can be cited. As the garnet-type solid electrolyte, for example, Li 7 La 3 Zr 2 O 12 、Li 7-x La 3 (Zr 2-x Nb x )O 12 (0≤x≤2), Li 5 La3 Nb 2 O 12 etc. As perovskite-type solid electrolytes, examples include (Li, La)TiO 3 , (Li, La)NbO 3 , (Li, Sr)(Ta, Zr)O 3 etc. As sodium superionic conductor-type solid electrolytes, examples include Li(Al, Ti)(PO 4 ) 3 , Li(Al, Ga)(PO 4 ) 3 etc. As Li-P-O-based solid electrolytes, examples include Li 3 PO 4 , LIPON (a compound in which a part of the O in Li 3 PO 4 is replaced by N), and as Li-B-O-based solid electrolytes, examples include Li 3 BO 3 , a compound in which a part of the O in Li 3 BO 3 is replaced by C, etc.

[0048] As halide solid electrolytes, solid electrolytes containing Li, M, and X (M represents at least one of Ti, Al, and Y, and X represents F, Cl, or Br) are suitable. Specifically, Li 6-3z Y z X 6 (X represents Cl or Br, and z satisfies 0 < z < 2), Li 6-(4-x)b (Ti 1-x Al x ) b F 6 (0 < x < 1, 0 < b ≤ 1.5). Among Li 6-3z Y z X 6 , Li 3 YX 6 (X represents Cl or Br) is more preferred in terms of excellent lithium ion conductivity, and Li 3 YCl 6 is further preferred. Additionally, for example, from the perspective of suppressing the oxidative decomposition of sulfide solid electrolytes, etc., it is preferred to contain both Li 6-(4-x)b (Ti 1-x Al x ) b F 6 (0 < x < 1, 0 < b ≤ 1.5) and solid electrolytes such as sulfide solid electrolytes.

[0049] 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, carbon, etc., preferably aluminum alloy foil or aluminum foil. Aluminum alloy foil and aluminum foil can be manufactured using powder. The shape of the positive electrode current collector is, for example, foil-like or mesh-like.

[0050] The negative electrode current collector collects current from the negative electrode active material layer. Examples of the material of 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. Battery structure

[0051] The structure of a solid-state battery has a stacked structure of positive electrode / solid electrolyte layer / negative electrode. Solid-state batteries include so-called all-solid-state batteries that use solid electrolytes as electrolytes, and the solid electrolytes may also contain less than 10% by mass of electrolytes relative to the total amount of electrolytes. In addition, the solid electrolyte may also be a composite solid electrolyte comprising an inorganic solid electrolyte and a polymer electrolyte.

[0052] 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 multilayer structure of two or more layers. Solid-state batteries can have, for example, Figure 6 The cross-sectional structure shown in FIG. 1 is a solid electrolyte layer B. Figure 6 That is a double-layer structure. Figure 6 This is a schematic cross-sectional view showing an example of a solid-state battery. Figure 6 The solid-state battery shown 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, in which the surface of the coated positive electrode active material 103 is coated with an LTAF electrolyte or LiNbO 3 Electrolyte coating. In addition, the solid-state battery can also be constructed by sealing the stacked end faces (side faces) of the stacked structure of the positive electrode / solid electrolyte layer / negative electrode with resin. The current collector of the electrode can also be configured with a buffer layer, an elastic layer or a positive temperature coefficient (PTC) thermistor layer on the surface. Battery

[0053] The laminated battery in the present disclosure is typically a lithium-ion secondary battery. As the purpose of the battery, for example, power sources of vehicles such as hybrid electric vehicles (HEV), plug-in hybrid electric vehicles (PHEV), pure electric vehicles (BEV), gasoline vehicles, and diesel vehicles can be cited. It is particularly preferred to be used as a driving power source for hybrid electric vehicles (HEV), plug-in hybrid electric vehicles (PHEV) or pure electric vehicles (BEV). In addition, the battery in the present disclosure can also be used as a power source for mobile bodies other than vehicles (such as railways, ships, and aircraft), and can also be used as a power source for electrical products such as information processing devices.

[0054] The present disclosure is not limited to the above-mentioned embodiments. The above-mentioned embodiments are merely examples, and any scheme having substantially the same configuration and exerting the same function and effect as the technical concept described in the claims of the present disclosure is included in the technical scope of the present disclosure.

Claims

1. A laminated battery comprising: an electrode body; and a laminate film covering and sealing the electrode body, The laminate film has a welded portion where the ends overlap each other and the inner surfaces are welded together, The weld portion includes two bent portions bent in an angular or arcuate shape to form an angle of 90° or less, and a rolled portion disposed on the front end side of the weld portion relative to the two bent portions and rolled up in a roll shape.

2. The laminated battery according to claim 1, wherein The angle of the bent portion is greater than 60°.

3. The laminated battery according to claim 1 or 2, wherein: The height of the welded 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.

4. A method for manufacturing a laminated battery, the laminated battery comprising: an electrode body; and a laminate film covering and sealing the electrode body, The laminate film has a welded portion where the ends thereof overlap each other and the inner surfaces thereof are welded together. in, The manufacturing method has the following features: A rolling step of rolling up the welded portion from the front end side in a roll shape; and In the punching step, a punching member is pressed against the rolled welded portion from at least two directions to bend the welded portion in an angular or arc shape at an angle of 90° or less to form two bent portions.

5. The method for manufacturing a laminated battery according to claim 4, wherein: The punching process is a process of pressing the punching member against each other from three directions.

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