Laminated battery and method of manufacturing laminated battery

Abstract

A laminate-type battery having an electrode body and a laminate film that covers and encloses the electrode body, wherein the laminate film has a fused portion in which the inner surface is fused by overlapping the ends, and the fused portion has three or more bending portions including two or more bending portions bent in an angle or arc shape at an angle of 90° or less, and one leading edge bending portion bent in an angle or arc shape at a position from the leading edge of the fused portion at an angle of less than 180°, and the fused portion has a shape in which at least a portion of the leading edge faces toward the electrode body.

Description

Technology 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 by a laminate film, a portion of the laminate film is fused to form a fused portion in order to encapsulate the electrode body.

[0003] For example, Japanese Patent Publication No. 2019-200973 discloses a method for manufacturing a secondary battery having at least one bent portion at one end of an outer body that has undergone laminate processing, comprising a step of bringing a pressing plate into contact with the starting point of the bending of the end of the outer body, and after the step of bringing it into contact, a step of sliding a pressing plate positioned opposite the pressing plate and the pressing plate so as to place the end between them, thereby forming a bent portion by bending the end around the starting point and clamping the end with the pressing plate and the pressing plate, wherein the surface sliding with the end of the pressing plate has an inclined surface for performing the bending of the end and a clamping surface for clamping the end, wherein the inclined surface is inclined in a cross-section perpendicular to the width direction of the pressing plate so that the cross-sectional area of ​​the pressing plate is narrowed in the sliding direction, and the inclined surface is inclined in the width direction. The problem to be solved

[0004] In a laminate-type battery in which an electrode body is covered by a single laminate film, the electrode body is enclosed by the laminate film by overlapping the ends of the laminate film and fusing their inner surfaces to form a fused portion. In addition, in a laminate-type battery in which an electrode body is covered by multiple laminate films, the electrode body is enclosed by overlapping the ends of the multiple laminate films and fusing their inner surfaces to form a fused portion. Furthermore, to improve the structural efficiency of the laminate-type battery, these fused portions are folded, for example, to reduce the overall external size of the laminate-type battery.

[0005] Here, when an impact is applied to an electrode body included in a laminated battery, the electrode body may be damaged, and the required battery performance may not be achieved. Therefore, impact resistance is required for laminated batteries, and it is also required to increase the impact resistance against external impacts in the fused part of the laminate film.

[0006] The present disclosure is made in consideration of the above circumstances and aims to provide a laminated battery having excellent impact resistance of the fused portion against external impact, and a method for manufacturing the laminated battery. means of solving the problem

[0007] <1>

[0008] Electrode body and,

[0009] having a laminate film that covers the above electrode body and encloses it inside,

[0010] The above laminate film has a fused portion in which the inner surface is fused by overlapping the ends, and

[0011] The above-mentioned fusion portion has three or more bending portions, including two or more bending portions bent in an angle or arc shape to form an angle of 90° or less, and one leading-side bending portion bent in an angle or arc shape to form an angle of less than 180° at a position from the leading edge of the fusion portion.

[0012] The above-mentioned fused portion is a laminate-type battery having a shape in which at least a portion of the tip faces the electrode body side.

[0013] <2>

[0014] A laminated battery described in <1>, wherein the above-mentioned bent portion and the above-mentioned tip-side bent portion are both bent into an arc shape.

[0015] <3>

[0016] A laminated battery described in <1> or <2>, wherein the position where the tip-side bending portion is placed is the position closest to the bending portion at the most proximate side of the fusion portion among two or more of the bending portions.

[0017] <4>

[0018] A laminated battery described in any one of <1> to <3>, wherein the fused portion is, as the bent portion, one or more right-angle bending portions bent in an angle or arc shape to form an angle of 70° or more and 90° or less, and one reverse-folded bending portion bent in an angle or arc shape to form an angle of 20° or less.

[0019] <5>

[0020] A laminate-type battery described in any one of <1> to <4>, wherein the shortest distance between the leading edge of the fused portion and the laminate film covering the electrode body is 0.5 mm or more and 5 mm or less.

[0021] <6>

[0022] As a method for manufacturing a laminated battery as described in <5>,

[0023] A process for preparing a post-fusion laminated battery having a planar fused portion in which the ends of laminate films overlap and the inner surfaces are fused, and

[0024] A back-folding bending process for forming a back-folded bending portion bent into an angle or arc shape at an angle of 20° or less in the fused portion of the laminate-type battery after the fusion, and

[0025] A right-angle bending process having a right-angle bending portion formed in an angled or arc-shaped manner such that the angle is 70° or more and 90° or less in the region of the source side of the fusion portion compared to the above-mentioned back-folded bending portion,

[0026] The above right-angle bending process is a process of forming the right-angle bending portion by bending the fused portion in stages by conveying between each pair of rollers of a roller pair group having at least three bending rollers that contact the bending side surface of the fused portion and have different contact angles with respect to the fused portion, and an equal number of opposing rollers formed at a position opposite to the bending rollers with the fused portion interposed therebetween.

[0027] In addition, the above right-angle bending process is a process of forming the leading edge portion of the fusion portion by bringing at least one bending roller in the above pair of rollers into contact with the leading edge portion of the above folded-back bending portion, a method for manufacturing a laminated battery. Effects of the invention

[0028] According to the present disclosure, a laminated battery having excellent impact resistance of the fused portion against external impact, and a method for manufacturing the laminated battery can be provided. Brief explanation of the drawing

[0029] FIG. 1 is a schematic cross-sectional view illustrating a laminated battery related to the present embodiment. FIG. 2 is a schematic cross-sectional view illustrating a laminated battery related to another aspect of the present embodiment. FIG. 3 is a schematic cross-sectional view illustrating a laminated battery related to another aspect of the present embodiment. FIG. 4 is a schematic cross-sectional view illustrating a laminated battery related to another aspect of the present embodiment. Figure 5 is a schematic cross-sectional view showing an example of a solid-state battery. Specific details for implementing the invention

[0030] <Laminated Battery>

[0031] A laminated battery related to an embodiment of the present disclosure comprises an electrode body and a laminate film that covers the electrode body and encloses it inside. The laminate film has a fused portion in which the inner surface is fused by overlapping the ends. The fused portion has three or more bending portions, including two or more bending portions that are bent in an angle or arc shape at an angle of 90° or less, and one leading edge bending portion that is bent in an angle or arc shape at a position from the leading edge of the fused portion at an angle of less than 180°. The fused portion has a shape in which at least a portion of the leading edge faces toward the electrode body.

[0032] Since at least a portion of the tip of the fusion section faces the electrode body side, even if an external impact is applied to the fusion section, the tip first comes into contact with the electrode body side (the laminate film covering the electrode body) and is absorbed, and subsequently, even if an additional external impact is applied to the fusion section, it becomes difficult for the fusion section to deform. As a result, the impact resistance of the fusion section is improved, and as a result, damage to the electrode body can be suppressed.

[0033] Hereinafter, an embodiment of a laminated battery related to the present disclosure will be described using drawings.

[0034] Each drawing shown below is schematic, and the size and shape of each part have been appropriately exaggerated to facilitate understanding.

[0035] (First mode)

[0036] FIG. 1 is a schematic cross-sectional view illustrating a laminated battery related to the present embodiment.

[0037] A laminated battery (10A) has an electrode body (2) and a laminate film (4) that covers the electrode body (2) and encloses it inside. The laminate film (4) has a fused portion (40) in which the inner surfaces are fused together by overlapping one end and the other end. The electrode body (2) has a shape in which the cross-section (20) (the cross-section of the side where the fused portion (40) is formed in FIG. 1) is an inclined surface. The fused portion (40) is formed outwardly from the end of the side that is further outwardly extended (the lower end of the cross-section (20) in FIG. 1) in the cross-section (20) of the electrode body (2) which is an inclined surface. The fusion section (40) has a total of three bends: a right-angle bend (40a) bent in an arc shape at an angle of approximately 90° from the source side of the fusion section (40) (i.e., the position closest to the electrode body (2)) to the tip side (400); a reverse-bent bend (40b) bent in an arc shape at an angle of approximately 0°; and a tip-side bend (40c) bent in an arc shape at an angle of approximately 90° from the tip side (400) of the fusion section (40). The leading edge bend (40c) is positioned closest to the right-angle bend (40a), which corresponds to the most fundamental bend of the fusion part (40), among all the remaining bends (i.e., the right-angle bend (40a) and the reverse-bent bend (40b)).

[0038] Here, the angle of the fusion portion in the present disclosure refers to the angle at the smallest angle formed by the fusion portions on both sides with the bend portion in between.

[0039] The fusion portion (40) has a shape in which the tip (400) faces toward the electrode body (2). The fusion portion (40) shown in FIG. 1 has a shape in which, in the length direction of the fusion portion (40) (depth direction in FIG. 1), all regions of the tip (400) face toward the electrode body (2).

[0040] Here, the fact that the tip has a shape facing the electrode body means that the tip in the fusion part is positioned closer to the electrode body than the tip-side bending part.

[0041] As such, the laminated battery (10A) shown in FIG. 1 has a shape in which the tip (400) faces the electrode body (2). When an external impact is applied to this fused part (40), for example, when an impact is applied to the fused part (40) from the right direction in FIG. 1. At that time, the fused part (40) is deformed starting from the right bending part (40a), and the tip (400) first comes into contact with and is received by the electrode body (2) side (the laminate film (4) covering the electrode body (2)). After that, even if an external impact (for example, from the right direction in FIG. 1) continues to be applied to the fused part (40), the fused part (40) is difficult to deform because the tip (400) is in contact with the electrode body (2). Thus, the impact resistance of the fusion part (40) is improved, and as a result, damage to the electrode body (2) caused by impact applied to the fusion part (40) can be suppressed.

[0042] In addition, FIG. 1 shows an embodiment having three bends that are curved in an arc shape, but the bends may be bent in an angle shape, that is, in an angled shape.

[0043] Additionally, FIG. 1 shows an embodiment in which, in the longitudinal direction of the fusion part (40), all regions of the tip (400) have a shape facing toward the electrode body (2), but the tip of the fusion part only needs to have a shape in which at least a portion faces toward the electrode body. Since at least a portion of the tip of the fusion part has a shape facing toward the electrode body, even if an external impact is applied to the fusion part, the portion of the tip facing toward the electrode body first comes into contact with and is absorbed by the electrode body, thereby improving the impact resistance of the fusion part and suppressing damage to the electrode body.

[0044] In addition, the laminated battery related to the embodiment of the present disclosure may have three or more bending portions, including two or more bending portions bent in an angle or arc shape at an angle of 90° or less at the fusion portion, and one leading-side bending portion bent in an angle or arc shape at a position from the leading edge of the fusion portion at an angle of less than 180°. As a bending portion, the fusion portion is preferably to have one or more right-angle bending portions bent in an angle or arc shape at an angle of 70° or more and 90° or less, and one reverse-bent bending portion bent in an angle or arc shape at an angle of 20° or less, from the viewpoint of improving structural efficiency in the fusion portion.

[0045] (Second mode)

[0046] FIG. 2 is a schematic cross-sectional view illustrating a laminated battery related to another aspect of the present embodiment.

[0047] A laminated battery (10B) has an electrode body (2) and a laminate film (4) that covers the electrode body (2) and encloses it inside. The laminate film (4) has a fused portion (42) in which the inner surfaces are fused together by overlapping one end and the other end. The fusion section (42) has a total of 5 bends, extending from the source side of the fusion section (42) (i.e., the position closest to the electrode body (2)) to the tip side (420), a right-angle bend (42a) bent in an arc shape at an angle of approximately 90°, a right-angle bend (42b) bent in an arc shape at an angle of approximately 90°, a reverse-bent bend (42c) bent in an arc shape at an angle of approximately 0°, a right-angle bend (42d) bent in an arc shape at an angle of approximately 90°, and a tip-side bend (42e) bent in an arc shape at an angle of approximately 90° from the tip side (420) of the fusion section (42). The leading edge bend (42e) is positioned closest to the right-angle bend (42a), which corresponds to the most fundamental bend of the fusion part (42), among all the remaining bends (i.e., the right-angle bends (42a, 42b, 42d) and the reverse-bent bend (42c)).

[0048] The fusion portion (42) has a shape in which the tip (420) faces toward the electrode body (2). That is, the tip (420) of the fusion portion (42) is positioned closer to the electrode body (2) than the tip-side bending portion (42e). The fusion portion (42) shown in FIG. 2 has a shape in which all regions of the tip (420) face toward the electrode body (2) in the longitudinal direction (depth direction in FIG. 2) of the fusion portion (42).

[0049] As such, the laminated battery (10B) shown in FIG. 2 has a shape in which the tip (420) faces toward the electrode body (2). When an external impact is applied to this fused portion (42), for example, when an impact is applied to the fused portion (42) from the right direction in FIG. 2, the fused portion (42) is deformed starting from the right bending portion (42a), and the folded-back bending portion (42c) first comes into contact with the electrode body (2) side (the laminate film (4) covering the electrode body (2)). However, as additional impact is continuously applied, the folded-back bending portion (42c) that is in contact with the electrode body (2) side is thought to slide and become misaligned (misaligned in the upward direction in FIG. 2). After that, if an additional impact is continuously applied to the fused portion (42), the tip portion (420) then comes into contact with the electrode body (2) side (the laminate film (4) covering the electrode body (2)). After that, even if an additional impact is continuously applied to the fused portion (42) from the outside (for example, from the right direction in FIG. 2), the fused portion (42) is difficult to deform because the tip portion (420) is in contact with the electrode body (2) side. As a result, the impact resistance of the fused portion (42) is improved, and as a result, damage to the electrode body (2) caused by an impact applied to the fused portion (42) can be suppressed.

[0050] In addition, FIG. 2 shows an embodiment having five bends that are curved in an arc shape, but the bends may be angled, that is, bent into an angled shape.

[0051] Additionally, FIG. 2 shows an embodiment in which, in the longitudinal direction of the fusion portion (42), all regions of the tip (420) have a shape facing toward the electrode body (2), but at least a portion of the tip of the fusion portion has a shape facing toward the electrode body.

[0052] (Third Mode)

[0053] FIG. 3 is a schematic cross-sectional view illustrating a laminated battery related to another aspect of the present embodiment.

[0054] A laminated battery (10C) has an electrode body (2) and a laminate film (4) that covers the electrode body (2) and seals it inside. The laminate film (4) has a fused portion (44) in which the inner surfaces are fused together by overlapping the one end and the other end. The fused portion (44) has a total of three bends: a right-angle bend (44a) bent in an arc shape at an angle of approximately 90° from the source side of the fused portion (44) (i.e., the position closest to the electrode body (2)) to the tip side (440); a reverse-folded bend (44b) bent in an arc shape at an angle of approximately 0°; and a tip-side bend (44c) bent in an arc shape at an angle of approximately 90° from the tip side (440) of the fused portion (44).

[0055] Additionally, the leading edge bend (44c) is positioned closest to the reverse bend (44b) among all the remaining bends (i.e., the right-angle bend (44a) and the reverse bend (44b)), which is not equivalent to the bend at the most fundamental side of the fusion part (44).

[0056] The fusion portion (44) has a shape in which the tip (440) faces toward the electrode body (2). That is, the tip (440) of the fusion portion (44) is positioned closer to the electrode body (2) than the tip-side bending portion (44c). The fusion portion (44) shown in FIG. 3 has a shape in which all regions of the tip (440) face toward the electrode body (2) in the longitudinal direction (depth direction in FIG. 3) of the fusion portion (44).

[0057] As such, the laminated battery (10C) shown in FIG. 3 has a shape in which the tip (440) faces the electrode body (2). When an external impact is applied to this fused portion (44), for example, when an impact is applied to the fused portion (44) from the right direction in FIG. 3, the fused portion (44) is deformed starting from the right bending portion (44a), and the tip (440) first comes into contact with and is received by the electrode body (2) side (the laminate film (4) covering the electrode body (2)). Subsequently, even if an external impact (for example, from the right direction in FIG. 3) continues to be applied to the fused portion (44), the fused portion (44) is difficult to deform because the tip (440) is in contact with the electrode body (2). Thus, the impact resistance of the fusion part (44) is improved, and as a result, damage to the electrode body (2) caused by impact applied to the fusion part (44) can be suppressed.

[0058] In addition, FIG. 3 shows an embodiment having three bends that are curved in an arc shape, but the bends may be bent in an angle shape, that is, in an angled shape.

[0059] Additionally, FIG. 3 shows an embodiment in which, in the longitudinal direction of the fusion portion (44), all regions of the tip (440) have a shape facing toward the electrode body (2), but at least a portion of the tip of the fusion portion has a shape facing toward the electrode body.

[0060] In the first to third embodiments shown in FIGS. 1 to 3, the cross-section of the electrode body is an inclined surface, but the shape of the electrode body is not limited to this. For example, as shown in FIG. 4, a rectangular electrode body (2D) may be used.

[0061] In a laminate-type battery related to an embodiment of the present disclosure, the leading edge of the fusion portion has a shape facing toward the electrode body. The shortest distance between the leading edge of the fusion portion and the laminate film covering the electrode body is preferably 0.5 mm or more and 5 mm or less, and more preferably 0.5 mm or more and 1 mm or less, from the perspective of improving the impact resistance of the fusion portion against external impact. In addition, the shortest distance between the leading edge of the fusion portion and the laminate film covering the electrode body refers, for example, to distance a1 in FIG. 1, distance a2 in FIG. 2, distance a3 in FIG. 3, and distance a4 in FIG. 4.

[0062] In the first to third embodiments shown in FIGS. 1 to 3, a laminate-type battery is shown in which an electrode body is covered with a single laminate film. However, the present disclosure is not limited to this, and a laminate-type battery may be shown in which an electrode body is covered with a plurality of laminate films. For example, as a laminate-type battery in which an electrode body is covered with two laminate films, the laminate-type battery may be shown in which the ends of two laminate films are overlapped and the inner surfaces are fused to form a fused portion.

[0063] <Method for Manufacturing a Laminated Battery>

[0064] Next, a method for manufacturing a laminated battery related to an embodiment of the present disclosure will be described.

[0065] A method for manufacturing a laminate-type battery comprises an electrode body and a laminate film covering the electrode body and encapsulating it internally. The laminate film has a fused portion in which the inner surfaces are fused by overlapping the ends. The fused portion has three or more bending portions, including two or more bending portions bent in an angle or arc shape at an angle of 90° or less, and one leading-side bending portion bent in an angle or arc shape at a position from the leading edge of the fused portion at an angle of less than 180°. The fused portion has a shape in which at least a portion of the leading edge faces toward the electrode body. As a bending portion, the fused portion has one back-folded bending portion bent in an angle or arc shape at an angle of 20° or less, and one or more right-angle bending portions formed on the origin side of the fused portion relative to the back-folded bending portion, bent in an angle or arc shape at an angle of 70° or more and 90° or less. This is a method for manufacturing a laminated battery.

[0066] And, a process for preparing a post-fusion laminated battery having a planar fused portion in which the ends of the laminate films overlap and the inner surfaces are fused, and

[0067] A back-folding bending process for forming a back-folded bending portion bent into an angle or arc shape at an angle of 20° or less in the fused portion of a laminate-type battery after fusion, and

[0068] A right-angle bending process having a right-angle bending section formed in an angled or arc-shaped manner at an angle of 70° or more and 90° or less in the region of the source side of the fusion section compared to the back-folded bending section,

[0069] The right-angle bending process is a process of forming a right-angle bend by bending the fused portion in stages by conveying between each pair of rollers of a roller pair group having at least three bending rollers that contact the bending side surface of the fused portion and have different contact angles with respect to the fused portion, and a number of opposing rollers equal to the number of bending rollers formed in a position opposite to the bending rollers with the fused portion interposed therebetween.

[0070] In addition, the right-angle bending process is a process of forming a leading edge bend by bringing the leading edge area of ​​the fusion section into contact with at least one bending roller in a pair of rollers, rather than the bent section that is folded back.

[0071] · Example of manufacturing a laminate-type battery of the first embodiment

[0072] First, the method of manufacturing a laminated battery of the first embodiment shown in FIG. 1 will be explained as an example. In the laminated battery (10A) of the first embodiment, the right-angle bending portion (40a), the reverse-bent bending portion (40b), and the leading edge bending portion (40c) can be formed by performing, for example, the reverse-bent bending process and the right-angle bending process shown below.

[0073] First, a laminated battery (laminated battery after fusion) having a flat fused portion (40) that is not folded is subjected to a folding operation to form a folded-back bending portion (40b) (folded-back bending process). The folding operation in the folded-back bending process may be, for example, a method of folding the fused portion (40) in stages by conveying between each pair of rollers in a group of rollers having a plurality of folding rollers that contact the surface of the folding side of the fused portion (40) (i.e., the bending side in the folded-back bending portion (40b)) and have different contact angles with respect to the fused portion (40), and an equal number of opposing rollers formed in a position opposite to the folding rollers with the fused portion (40) interposed therebetween.

[0074] Next, regarding the fused portion (40) in which the reverse-folded bend portion (40b) is formed, a bending operation is performed on the region of the fused portion (40) that is closer to the origin side than the reverse-folded bend portion (40b) to form a right-angle bend portion (40a) (right-angle bending process). The bending operation in the right-angle bending process may be, for example, a method of bending the fused portion (40) in stages by conveying between each pair of rollers of a roller pair group having an equal number of opposing rollers formed in a position opposite to the bending rollers with the fused portion (40) interposed therebetween, and at least three bending rollers that are in contact with the surface of the bending side of the fused portion (40) (i.e., the bending side in the right-angle bend portion (40a)) and have different contact angles with respect to the fused portion (40).

[0075] Additionally, in the right-angle bending process, at least one bending roller in the roller pair can be brought into contact with the area on the leading edge (400) side of the fusion section (40) rather than the bent portion (40b) that has been folded back, thereby forming an additional leading edge bending portion (40c). Additionally, when at least one bending roller in the roller pair is brought into contact with the area on the leading edge (400) side of the fusion section (40), contact may be made with the entire area of ​​the leading edge (400) in the longitudinal direction of the fusion section (40), or contact may be made only with a part of the leading edge (400) of the fusion section (40).

[0076] In the right-angle bending process, a right-angle bending portion (40a) is formed using the above-mentioned roller pair group having at least three bending rollers with different contact angles, and a front-side bending portion (40c) is formed by contacting at least one bending roller in the above-mentioned roller pair group to the front-side area (400) of the fusion portion (40), thereby suppressing the occurrence of springback in the fusion portion (40). Additionally, at least a portion of the front-side (400) of the fusion portion (40) can be shaped to face the electrode body (2), and the impact resistance of the fusion portion (40) can be improved.

[0077] · Example of manufacturing a laminate-type battery of the second embodiment

[0078] As a method for manufacturing a laminate-type battery of the second embodiment shown in FIG. 2, a method may be used in which, in the example of manufacturing a laminate-type battery of the first embodiment described above, a second right-angle bending process is performed after the back-folding bending process and also before the right-angle bending process, or after the right-angle bending process.

[0079] That is, a folded-back bend portion (42c) is formed in the same manner as the manufacturing example of the laminated battery of the first embodiment (folded-back bending process), and then a right-angle bend portion (42a) and a leading-side bend portion (42e) are formed in the same manner as the manufacturing example of the laminated battery of the first embodiment (right-angle bending process). After that, right-angle bend portions (42b and 42d) are formed, respectively, in the area between the folded-back bend portion (42c) and the leading-side bend portion (42e), and in the area between the folded-back bend portion (42c) and the right-angle bend portion (42a) (second right-angle bending process). The bending operation in the second right-angle bending process may be performed by, for example, by conveying between each pair of rollers in a group of rollers having a plurality of bending rollers that contact the surface of the bending side of the fusion part (42) (i.e., the tucked side in the right-angle bending part (42d) and have different contact angles with respect to the fusion part (42), and a number of opposing rollers formed in a position opposite to the bending rollers with the fusion part (42) interposed therebetween. In addition, the second right-angle bending process may be performed after the back-folding bending process and before the right-angle bending process.

[0080] According to the manufacturing example of the second embodiment of the laminated battery shown above, the occurrence of springback in the fused portion (42) can be suppressed. In addition, at least a portion of the tip (420) of the fused portion (42) can be shaped to face toward the electrode body (2), and the impact resistance in the fused portion (42) can be improved.

[0081] In addition, the method for manufacturing a laminated battery related to the embodiments of the present disclosure is not limited to the above method. For example, a method for manufacturing a laminated battery of the third embodiment shown in FIG. 3 may include forming a right-angle bending portion (44a), a back-folded bending portion (44b), and a leading edge bending portion (44c) by a separate bending process.

[0082] (Absence of battery)

[0083] Next, the electrode body and the laminate film constituting the laminate-type battery related to the present embodiment will be described.

[0084] (1) Laminate film

[0085] As for the laminate film, for example, a film having a metal layer can be cited, and a film with a three-layer structure having resin layers on each side of the metal layer can also be cited. In addition, in the film with a three-layer structure, the inner resin layer on the side of the electrode body (i.e., the resin layer to be fused) is made into a fused resin layer, and the resin layer on the outer surface opposite to the side of the electrode body is made into a protective resin layer.

[0086] For example, olefin-based resins such as polypropylene (PP) and polyethylene (PE) can be used as the material for the fusion resin layer. For example, aluminum, aluminum alloys, and stainless steel can be used as the material for the metal layer. For example, polyethylene terephthalate (PET) and nylon can be used as the material for the protective resin layer. 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 total thickness of the laminate film is, for example, 70 μm or more and 220 μm or less.

[0087] (2) Electrode

[0088] The electrode body functions as a power generation element of the battery. The shape of the electrode body is not particularly limited, but examples include a rectangular shape or a shape with an inclined cross-section. The electrode body typically comprises 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.

[0089] The positive electrode active material layer contains at least a positive electrode active material. The positive electrode active material layer may additionally contain at least one of a conductive material, an electrolyte, and a binder. The shape of the positive electrode active material is, for example, particulate. As a positive electrode active material, an oxide active material may be, for example. In addition, sulfur (S) may be used as the positive electrode active material.

[0090] It is preferable to include a lithium composite oxide as a positive electrode active material. The lithium composite oxide may contain at least one selected from the group consisting of F, Cl, N, S, Br, and I. In addition, the lithium composite oxide may 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 or P6 / mmc). In addition, the lithium composite oxide may have an O2 type structure in which the main arrangement of transition metals, oxygen, and lithium is O2.

[0091] As lithium composite oxides having a crystal structure belonging to R-3m, for example, Li x Me y O α X βExamples of compounds represented by (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, satisfying 0.5 ≤ x ≤ 1.5, 0.5 ≤ y ≤ 1.0, 1 ≤ α < 2, and 0 < β ≤ 1).

[0092] As lithium composite oxides having a crystal structure belonging to Immm, for example, Li x1 M 1 A 1 2 (satisfying 1.5 ≤ x1 ≤ 2.3), and M 1 It comprises 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 Complex oxides represented as (specific example Li2NiO2), Li (where the proportion of oxygen occupied in is 85 atomic% or more), Li 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, and M 1A represents at least one type selected from the group consisting of Ni, Co, Mn, Cu, and Fe, and M 1B Examples of complex oxides include those represented by , where represents at least one type 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 type selected from the group consisting of F, Cl, Br, S, and P.

[0093] Lithium composite oxides having a crystal structure belonging to P63-mmc include, for example, M1 x M2 y Examples of complex oxides include O2 (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).

[0094] As for lithium composite oxides having an O2 type structure, for example, Li x [Li α (Mn a Co b M c ) 1-α Examples include complex oxides represented by ]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, where M represents at least one selected from the group consisting of Ni, Mg, Ti, Fe, Sn, Zr, Nb, Mo, W, and Bi), and as a specific example, Li 0.744 [Li 0.145 Mn 0.625 Co 0.115 Ni 0.115 O2, etc. can be cited.

[0095] In addition, the positive electrode preferably comprises, 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, and it is more preferable that at least a portion 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 for the halide solid electrolyte coating at least a portion 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.

[0096] For example, carbon materials can be used as conductive 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. In addition, the liquid electrolyte (electrolyte) contains, for example, a support salt such as LiPF6 and a solvent such as a carbonate-based solvent. In addition, for example, rubber-based binders and fluoride-based binders can be used as binders.

[0097] The negative electrode active material layer contains at least a negative electrode active material. The negative electrode active material layer may additionally contain at least one of a conductive material, an electrolyte, and a binder. Examples of negative electrode active materials include metal active materials such as Li and Si, carbon active materials such as graphite, and Li4Ti5O. 12 Examples of oxide active materials include the above. The shape of the negative electrode current collector is, for example, thin or mesh. The conductive material, electrolyte, and binder are as described above.

[0098] 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. It is preferable that the electrolyte layer be a solid electrolyte layer. The electrolyte layer may have a separator.

[0099] As a solid electrolyte, it is preferable to include at least one solid electrolyte species selected from the group of solid electrolytes consisting of sulfide solid electrolytes, oxide solid electrolytes, and halogen solid electrolytes.

[0100] As a sulfide solid electrolyte, it is preferable to contain sulfur (S) as the main component of an anionic element, and furthermore, it is preferable to contain, for example, a Li element, an A element, and a 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 additionally contain at least one of O and a halogen element. Examples of halogen elements (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) and yLiI·zLiBr·(100-yz)(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).

[0101] Li 4-x Ge 1-x P x S4(0 < x < 1) … Equation (1)

[0102] In Equation (1), at least a portion 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 portion 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 portion of Li may be substituted with at least one selected from the group consisting of Na, K, Mg, Ca, and Zn. A portion of S may be substituted with a halogen. As for the halogen, there is at least one of F, Cl, Br, and I.

[0103] As an oxide solid electrolyte, it is preferable to contain oxygen (O) as the main component of an anionic element, and it may contain, for example, Li, Q element (Q represents at least one of Nb, B, Al, Si, P, Ti, Zr, Mo, W, and S), and O. Examples of oxide solid electrolytes include garnet-type solid electrolytes, perovskite-type solid electrolytes, nasicon-type solid electrolytes, Li-PO-based solid electrolytes, Li-BO-based solid electrolytes, etc. Examples of garnet-type solid electrolytes include Li7La3Zr2O 12 , Li 7-x La3(Zr 2-x Nb x )O 12 (0 ≤ x ≤ 2), Li5La3Nb2O 12 Examples include perovskite-type solid electrolytes such as (Li, La)TiO3, (Li, La)NbO3, (Li, Sr)(Ta, Zr)O3, etc. Examples of nasicon-type solid electrolytes such as Li(Al, Ti)(PO4)3, Li(Al, Ga)(PO4)3, etc. Examples of Li-PO-based solid electrolytes such as Li3PO4 and LIPON (a compound in which some of the O of Li3PO4 are replaced with N), and examples of Li-BO-based solid electrolytes such as Li3BO3 and a compound in which some of the O of Li3BO3 are replaced with C, etc.

[0104] As a halide solid electrolyte, a solid electrolyte comprising Li, M, and X (M represents at least one of Ti, Al, and Y, and X represents F, Cl, or Br) is preferred. 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 preferable. Li6-3z Y z Among X6, Li3YX6 (where X represents Cl or Br) is more preferable due to its excellent lithium ion conductivity, and furthermore, 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, for example, from the perspective of suppressing the oxidative decomposition of the sulfide solid electrolyte.

[0105] The positive electrode current collector collects current from the positive electrode active material layer. Examples of materials for the positive electrode current collector include stainless steel, aluminum, nickel, iron, titanium, carbon, etc., and aluminum alloy foil or aluminum foil is preferred. Aluminum alloy foil and aluminum foil may be manufactured using powder. The shape of the positive electrode current collector is, for example, thin or mesh.

[0106] The negative electrode current collector collects current from the negative electrode active material layer. Examples of materials for the negative electrode current collector include metals such as copper, stainless steel, and nickel. Examples of shapes for the negative electrode current collector include thin films and mesh films.

[0107] · Battery structure

[0108] The structure of the solid-state battery has a stacked 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 less than 10 mass% of the electrolyte solution relative to the total amount of the electrolyte. In addition, the solid electrolyte may be a composite solid electrolyte comprising an inorganic solid electrolyte and a polymer electrolyte.

[0109] 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.

[0110] The solid electrolyte layer may be a single-layer structure or a multi-layer structure of two or more layers.

[0111] The solid-state battery may have a cross-sectional structure as shown in FIG. 5, for example, and the solid electrolyte layer B may have a two-layer structure as shown in FIG. 5. FIG. 5 is a schematic cross-sectional view showing an example of a solid-state battery. The solid-state battery shown in FIG. 5 has a negative electrode comprising a negative electrode current collector (113) and a negative electrode active material layer (A), a solid electrolyte layer (B), and a positive electrode comprising 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 aid (105), and a binder (109). The positive electrode active material layer (C) comprises a coated positive electrode active material (103), a conductive aid (107), and a binder (111), and the coated positive electrode active material (103) has a surface of the positive electrode active material coated with an LTAF electrolyte or a LiNbO3 electrolyte.

[0112] In addition, the solid-state battery may be configured by encapsulating a cross-section (side) of a stacked structure of a positive electrode / solid electrolyte layer / negative electrode with resin. The current collector of the electrode may be configured such that a buffer layer, an elastic layer, or a PTC (Positive Temperature Coefficient) thermistor layer is disposed on its surface.

[0113] ·battery

[0114] The battery in the present disclosure is typically a lithium-ion secondary battery. Examples of applications for the battery include power sources for vehicles such as hybrid electric vehicles (HEV), plug-in hybrid electric vehicles (PHEV), electric vehicles (BEV), gasoline vehicles, and diesel vehicles. In particular, it is preferred to use it as a power source for driving hybrid electric vehicles (HEV), plug-in hybrid electric vehicles (PHEV), or electric vehicles (BEV). Furthermore, the battery in the present disclosure may be used as a power source for mobile bodies other than vehicles (e.g., railways, ships, aircraft) and as a power source for electrical products such as information processing devices.

[0115] The present disclosure is not limited to the above embodiments. The above embodiments are examples, and any configuration having substantially the same structure as the technical concept described in the claims of the present disclosure and exhibiting the same functional effect is included within the technical scope of the present disclosure. Explanation of the symbols

[0116] 2 : Electrode 4 : Laminate film 10A, 10B, 10C: Laminated battery 20 : Cross-section 40a, 42a, 42b, 42d, 44a: Right-angle bends 40b, 42c, 44b: Back-folded bend 40c, 42e, 44c: Tip-side bend 400, 420, 440 : Front 101 : Negative electrode active material 103 : Coated positive electrode active material 105, 107: Challenge Supplements 109, 111 : Binder 113 : Bu-geuk entire house 115 : Entire house of a straight play A: Negative electrode active material layer B: Solid electrolyte layer C: Positive electrode active material layer

Claims

Claim 1 A laminate-type battery having an electrode body and a laminate film that covers and encloses the electrode body, wherein the laminate film has a fused portion in which the inner surface is fused by overlapping the ends, and the fused portion has three or more bending portions including two or more bending portions that are bent in an angle or arc shape to form an angle of 90° or less, and one leading-side bending portion that is bent in an angle or arc shape to form an angle of less than 180° at a position from the leading end of the fused portion, and the fused portion has a shape in which at least a portion of the leading end faces toward the electrode body. Claim 2 A laminated battery according to claim 1, wherein the bent portion and the tip-side bending portion are both bent into an arc shape. Claim 3 A laminate-type battery according to claim 1, wherein the position where the leading edge bend is placed is the position closest to the bend closest to the origin of the fusion part among two or more of the bends. Claim 4 A laminate-type battery according to claim 1, wherein the shortest distance between the leading edge of the fusion portion and the laminate film covering the electrode body is 0.5 mm or more and 5 mm or less. Claim 5 A laminated battery according to claim 1, wherein the fusion portion is the bending portion, having one re-folded bending portion bent in an angle or arc shape at an angle of 20° or less, and one or more right-angle bending portions formed on the origin side of the fusion portion relative to the re-folded bending portion and bent in an angle or arc shape at an angle of 70° or more and 90° or less. Claim 6 A method for manufacturing a laminate-type battery according to claim 5, comprising: a process for preparing a post-fusion laminate-type battery having a planar fused portion in which the ends of laminate films overlap and their inner surfaces are fused; a back-folding bending process for forming a back-folding bend portion bent in an angle or arc shape at an angle of 20° or less in the fused portion of the post-fusion laminate-type battery; and a right-angle bending process for forming a right-angle bend portion bent in an angle of 70° or more and 90° or less in a region on the origin side of the fused portion relative to the back-folding bend portion, wherein the right-angle bending process comprises at least three bending rollers that contact the bending side surface of the fused portion and have different contact angles with respect to the fused portion, and each of a roller pair group having an equal number of opposing rollers formed at a position opposite to the bending rollers with the fused portion interposed therebetween. A method for manufacturing a laminated battery, wherein the fused portion is bent stepwise by conveying between a pair of rollers to form the right-angle bend portion, and further wherein the right-angle bending process is a process of forming the leading edge bend portion by bringing at least one bending roller in the group of roller pairs into contact with the leading edge portion of the fused portion rather than the reverse-folded bend portion.

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