Battery and method for manufacturing the battery

Abstract

To provide a battery in which thermal deformation of a sealing member is inhibited, as a main object disclosed herein.SOLUTION: To solve the above problem, the present disclosure provides a battery including: a layered member that includes an electrode layered body including a plurality of electrodes layered in a thickness direction, and a sealing member made of resin arranged along an outer periphery of the electrode layered body; a side surface member arranged at a side surface part of the layered member; and an outer package that covers the layered member and the side surface member. When the battery is viewed from a side surface which is the side surface member side, the outer package is arranged to cover a surface configuring an outer periphery of the side surface member, and a surface configuring an outer periphery of the layered member. The side surface member includes a metal foil, and a resin layer arranged on one main surface of the metal foil. The resin layer includes a first protruding part and a second protruding part extending to a first direction orthogonal to the thickness direction. The sealing member is arranged between the first protruding part and the second protruding part. Each of the first protruding part and the second protruding part are welded to the outer package.SELECTED DRAWING: Figure 2

Description

Technical Field

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

Background Art

[0002] A battery such as a lithium-ion secondary battery generally includes an electrode body having 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. The electrode body is sealed, for example, in an internal space surrounded by an exterior material. For example, Patent Document 1 discloses a lithium polymer secondary battery including an electrode assembly, an exterior body surrounding the outside of the electrode assembly, and a first cover and a second cover for sealing the exterior body.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] A battery having a laminated member in which a resin sealing member is disposed along the outer periphery of an electrode laminate has been considered. The resin sealing member is disposed, for example, to seal an electrolytic solution present inside the electrode laminate. The resin sealing member may undergo thermal deformation, for example, when welding the exterior body.

[0005] The present disclosure has been made in view of the above circumstances, and a main object thereof is to provide a battery in which thermal deformation of the sealing member is suppressed.

Means for Solving the Problems

[0006] [1] A battery comprising: a laminated member having an electrode laminate including a plurality of electrodes laminated in a thickness direction and a resin sealing member disposed along an outer edge of the electrode laminate; a side member disposed on a side surface portion of the laminated member; and an exterior body covering the laminated member and the side member. When the battery is viewed from the side member side in a side view, the exterior body is disposed so as to cover a surface constituting an outer edge of the side member and a surface constituting an outer edge of the laminated member. The side member has a metal foil and a resin layer disposed on one main surface of the metal foil. The resin layer has a first protrusion and a second protrusion extending in a first direction orthogonal to the thickness direction, and the sealing member is disposed between the first protrusion and the second protrusion. The first protrusion and the second protrusion are each welded to the exterior body.

[0007] [2] The electrode has a first current collector and an electrode layer disposed on at least one surface of the first current collector in the thickness direction. The electrode laminate has a second current collector at an end portion in the thickness direction. The exterior body has an exposed portion where the second current collector is exposed in the thickness direction. The battery according to [1].

[0008] [3] The side member is in surface contact with a surface of the sealing member in the first direction. The battery according to [1] or [2].

[0009] [4] The electrode laminate has a plurality of bipolar electrodes as the electrodes. The battery according to any one of [1] to [3].

[0010] [5] The battery is a liquid-based battery in which the electrode laminate contains an electrolytic solution. The battery according to any one of [1] to [4].

[0011] [6] The manufacturing method of the battery described above, comprising: a preparation step of preparing the laminated member and the side member; an arrangement step of arranging the side member on the side surface of the laminated member such that the sealing member is disposed between the first protrusion and the second protrusion; a covering step of covering the surface constituting the outer edge of the side member and the surface constituting the outer edge of the laminated member with the exterior body; and a welding step of heating the portion of the exterior body covering the side member to weld the exterior body to the first protrusion and the second protrusion.

Advantages of the Invention

[0012] In the present disclosure, there is an effect that a battery capable of suppressing thermal deformation of the sealing member can be provided.

Brief Description of the Drawings

[0013]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Figure 13

[0014] Hereinafter, the battery and the method for manufacturing the battery in the present disclosure will be described in detail with reference to the drawings. Each of the drawings shown below is schematically illustrated, and the size and shape of each part are exaggerated as appropriate for easy understanding. Also, in this specification, when expressing the manner of arranging one member with respect to another member, if it is simply described as "above" or "below", unless otherwise specified, it includes both the case where another member is arranged directly above or directly below so as to be in contact with a certain member, and the case where another member is arranged above or below a certain member via another member.

[0015] A. Battery FIG. 1 is a schematic perspective view illustrating a laminated member and a side member in the present disclosure. The laminated member 10 shown in FIG. 1(a) has a top surface portion 10a, a bottom surface portion 10b facing the top surface portion 10a in the thickness direction Z, and four side surface portions (a first side surface portion 10c, a second side surface portion 10d, a third side surface portion 10e, and a fourth side surface portion 10f) connecting the top surface portion 10a and the bottom surface portion 10b. Further, in FIG. 1(b), a first side member 20A is arranged on the first side surface portion 10c of the laminated member 10, and a second side member 20B is arranged on the second side surface portion 10d of the laminated member 10. Here, as shown in FIGS. 3(a) and (b) to be described later, the laminated member 10 has an electrode laminate 6 including a plurality of electrodes E laminated in the thickness direction Z, and a sealing member 7 arranged along the outer edge E1 of the electrode laminate 6 when viewed from the thickness direction Z.

[0016] FIG. 2 is a schematic perspective view and a schematic cross-sectional view illustrating a battery (electrode laminate, side member, and exterior body) in the present disclosure. FIG. 2(c) is a cross-sectional view taken along line A-A of FIG. 2(b). As shown in FIG. 2(a), the exterior body 30 is, for example, a single film (laminate film). Further, as shown in FIGS. 2(b) and 2(c), the exterior body 30 is folded so as to cover the laminate member 10 and the side member 20. Note that, as shown in FIGS. 2(b) and 2(c), in the battery 100, a part of the laminate member 10 (a part of the top surface portion 10a and the bottom surface portion 10b) is exposed from the exposed portion 31 of the exterior body 30.

[0017] Further, as shown in FIG. 4 described later, the side member 20 has a metal foil 21 and a resin layer 22 disposed on one main surface of the metal foil 21. The resin layer 22 has a first protrusion 23a and a second protrusion 23b extending in a first direction X orthogonal to the thickness direction Z. Then, as shown in FIG. 2(c), a sealing member 7 is disposed between the first protrusion 23a and the second protrusion 23b, and the first protrusion 23a and the second protrusion 23b are each welded to the exterior body 30.

[0018] According to the present disclosure, since the side member is disposed on the side surface portion of the laminate member such that the sealing member is disposed between the first protrusion and the second protrusion, and the first protrusion and the second protrusion are each welded to the exterior body, a battery is obtained in which thermal deformation of the sealing member is suppressed.

[0019] Further, in the battery in the present disclosure, the exterior body is welded to the surface (outer peripheral surface) constituting the outer edge of the side member. Therefore, for example, it is possible to suppress the occurrence of unexpected wrinkles as compared with the case of forming an end contact portion by adhering the exterior bodies without using the side member.

[0020] 1. Configuration of Battery The battery in the present disclosure includes at least a laminate member having an electrode laminate and a sealing member, a side member, and an exterior body.

[0021] (1) Laminate Member FIG. 3 is a schematic plan view and a schematic cross-sectional view illustrating a laminated member in the present disclosure. FIG. 3(b) is a cross-sectional view taken along line A-A of FIG. 3(a). As shown in FIGS. 3(a) and 3(b), the laminated member 10 includes an electrode laminate 6 including a plurality of electrodes E laminated in the thickness direction Z, and a sealing member 7 disposed along the outer edge E1 of the electrode laminate 6 when viewed from the thickness direction Z.

[0022] The electrode laminate includes a plurality of electrodes laminated in the thickness direction. As shown in FIG. 3(b), usually, the electrode E has a first current collector 1 and an electrode layer (a positive electrode active material layer 2 and a negative electrode active material layer 3) disposed on at least one surface of the first current collector in the thickness direction Z. The electrode laminate 6 shown in FIG. 3(b) has, as the electrode E, a bipolar electrode BP1, a bipolar electrode BP2, a positive electrode side end electrode CA, and a negative electrode side end electrode AN. The bipolar electrode BP1 and the bipolar electrode BP2 each have a first current collector 1, a positive electrode active material layer 2 disposed on one surface of the first current collector 1, and a negative electrode active material layer 3 disposed on the other surface of the first current collector 1. The positive electrode side end electrode CA has a first current collector 1 and a positive electrode active material layer 2 disposed on one surface of the first current collector 1. The negative electrode side end electrode AN has a first current collector 1 and a negative electrode active material layer 3 disposed on one surface of the first current collector 1. On the other hand, although not particularly shown, the electrode laminate in the present disclosure may not have a bipolar electrode.

[0023] Also, as shown in FIG. 3(b), the electrode laminate 6 may have a second current collector 5 on the first current collector 1 at the end in the thickness direction Z (in FIG. 3(b), the first current collector 1 in the positive electrode side end electrode CA and the first current collector 1 in the negative electrode side end electrode AN). When the electrode laminate having such a second current collector is covered with an exterior body having an exposed portion as shown in FIG. 1, the second current collector can be exposed from the exterior body. As a result, a large current can be taken out from the top surface and the bottom surface of the laminated member. The thickness of the second current collector is preferably thicker than the thickness of the first current collector. When the electrode laminate has a second current collector, the second current collector becomes a member constituting the top surface portion and the bottom surface portion of the laminated member.

[0024] Further, as shown in FIG. 3(b), the electrode laminate 6 usually includes power generation units U (U1 to U3). Each power generation unit U includes a positive electrode active material layer 2, a negative electrode active material layer 3, and a separator 4 disposed between the positive electrode active material layer 2 and the negative electrode active material layer 3. The power generation unit U is sealed with a sealing member 7. Further, the inside of the power generation unit U may be filled with an electrolytic solution. As a result, the positive electrode active material layer 2, the negative electrode active material layer 3, and the separator 4 are each impregnated with the electrolytic solution. Also, the electrode laminate in the present disclosure may have one power generation unit or two or more power generation units.

[0025] The electrode laminate 6 shown in FIG. 3(b) has a plurality of power generation units (U1, U2, U3) laminated in the thickness direction Z. As shown in FIG. 3(b), the plurality of power generation units may be directly connected to each other. Although not particularly shown, the plurality of power generation units may be connected in parallel to each other. The plurality of power generation units are independent of each other so that the electrolytic solution does not flow between them. In FIG. 3(b), the plurality of power generation units U1 to U3 are independent of each other so that the electrolytic solution does not flow between them. For example, the power generation unit U1 and the power generation unit U2 are partitioned by the first current collector 1 and the sealing member 7 and are independent of each other.

[0026] The sealing member is disposed along the outer edge of the electrode laminate as viewed from the thickness direction. Further, the sealing member is a member that constitutes the top and bottom surfaces of the laminated member, and is also a member that constitutes the side surface of the laminated member where the side member described later is disposed. As shown in FIG. 3(a), the sealing member 7 may be disposed along the entire circumference of the outer edge E1 of the electrode laminate 6. On the other hand, although not shown, the sealing member may be disposed along a part of the outer edge of the electrode laminate. Here, as shown in FIG. 3(a), if the length between the outer edge E1 of the electrode laminate 6 and the outer edge E2 of the sealing member 7 is W1, W1 may be the same or different on the outer periphery of the laminated member.

[0027] Here, specifically, it will be described in "B. Method for manufacturing battery", but the sealing member includes, for example, a frame member containing resin and a liquid injection frame (liquid injection frame sealed with resin).

[0028] Examples of the planar shape of the laminated member in the thickness direction include quadrilaterals such as squares and rectangles. Note that the planar shape of the laminated member can be regarded as the shape of the region surrounded by the outer edge E2 (the outer edge of the sealing member 7) of the laminated member, as shown in Fig. 3(a). The length of each side constituting the planar shape of the laminated member (the length of each side constituting the outer edge E2) is, for example, 30 cm or more, may be 60 cm or more, and may be 1 m or more. On the other hand, the length of each of the above sides is, for example, 3 m or less.

[0029] (2) Side member The side member in the present disclosure is disposed on the side surface of the laminated member. Here, the "side surface of the laminated member" refers to the four surfaces (the first side surface 10c, the second side surface 10d, the third side surface 10e, and the fourth side surface 10f) of the laminated member that connect the top surface 10a and the bottom surface 10b of the laminated member 10 in the thickness direction Z, as shown in Fig. 1(a). Note that in this specification, the top surface and the bottom surface of the laminated member can be regarded as the main surfaces of the laminated member.

[0030] First, the shape of the side member in the present disclosure will be described. Fig. 4 is a schematic perspective view and a schematic cross-sectional view illustrating the side member in the present disclosure. Fig. 4(b) is a cross-sectional view taken along the line A-A of Fig. 4(a), and Fig. 4(d) is a cross-sectional view taken along the line A-A of Fig. 4(c). Note that for ease of understanding, Figs. 4(b) and (d) are appropriately enlarged compared to Figs. 4(a) and (c). Fig. 5 is a schematic perspective view illustrating the side member in the present disclosure.

[0031] As shown in FIGS. 4(a) to 4(d), the side member 20 has a metal foil 21 and a resin layer 22 disposed on one main surface of the metal foil 21. Here, the "main surface of the metal foil" refers to the surface of the metal foil whose normal direction is parallel to the normal direction of the side surface of the laminated member on which it is disposed. Further, as shown in FIGS. 4(b) and 4(d), it has a first protrusion 23a and a second protrusion 23b extending in a first direction X orthogonal to the thickness direction Z. Also, as shown in FIG. 2(c), the first protrusion 23a and the second protrusion 23b are each welded to the exterior body 30. The exterior body will be described later.

[0032] Here, as shown in FIGS. 4(a) and 4(c), the side member 20 having the first protrusion 23a and the second protrusion 23b can be regarded as having a groove 24 extending in a second direction Y orthogonal to the first direction X. As shown in FIGS. 4(a) and 4(c), the groove 24 may penetrate the side member 20 in the second direction Y. On the other hand, as shown in FIG. 5(a), the groove may not penetrate the side member 20 in the second direction Y.

[0033] Also, as shown in FIGS. 4(a) and 4(b), the metal foil 21 may be disposed in the groove 24 of the side member 20. In other words, the metal foil 21 may be disposed on the surface of the side member in the extending direction of the first protrusion 23a and the second protrusion 23b (the left direction of the paper surface in FIG. 4(b)). On the other hand, as shown in FIGS. 4(c) and 4(d), the metal foil 21 may not be disposed in the groove 24 of the side member 20. In FIG. 4(d), the metal foil 21 is disposed on the surface of the side member opposite to the extending direction of the first protrusion 23a and the second protrusion 23b (the left direction of the paper surface in FIG. 4(d)). Here, when the metal foil is disposed as shown in FIG. 4(d), the metal foil may have an adhesive layer on the surface not in contact with the resin layer. This is because when the metal foil has an adhesive layer, the exterior body can also be well adhered to the metal foil through the adhesive layer.

[0034] Also, when the side member is viewed in a plan view from the normal direction of the main surface of the metal foil (the first direction X in FIG. 4), it is preferable that the area of the metal foil is smaller than the area of the resin layer. The ratio of the area of the metal foil to the area of the resin layer is, for example, 0.80 or more and 0.99 or less. Further, as shown in FIG. 4(c), in the direction orthogonal to the normal direction of the main surface of the metal foil (the second direction Y in FIG. 4), it is preferable that the length of the metal foil is shorter than the length of the resin layer. In the second direction, the ratio of the length of the metal foil to the length of the resin layer is, for example, 0.80 or more and 0.99 or less.

[0035] Also, as shown in FIG. 5(b), the laminated member 20 may have a through hole 25 penetrating the laminated member 20 in the first direction X. For example, the voltage of the battery can be managed by connecting a substrate (for example, an FPC substrate) extending from the through hole to a voltmeter.

[0036] Next, the dimensional relationship between the laminated member and the side member in the present disclosure will be described. FIG. 6 is a schematic side view and a schematic cross-sectional view illustrating the battery in the present disclosure. Specifically, FIG. 6(a) is a view of the battery viewed from the side member side when the side member is disposed on the first side surface or the second side surface of the laminated member. Further, FIG. 6(b) is a schematic cross-sectional view of the battery portion where the laminated member is disposed. As shown in FIG. 6, when viewed from the side member side, the outer edge E3 of the laminated member 10 may not coincide with the outer edge E4 of the side member. On the other hand, although not shown, the outer edge of the laminated member may coincide with the outer edge of the side member. That is, when the battery is viewed from the side member side, the dimension (area) of the laminated member may be equal to or different from the area of the side member. In the above side view, the ratio of the area of the side member to the area of the laminated member is preferably 1.0 or more. The ratio of the areas may be 1.1 or more, or may be 1.2 or more. On the other hand, the ratio of the areas is, for example, 1.5 or less, may be 1.4 or less, or may be 1.3 or less.

[0037] As shown in FIGS. 2(c) and 6(b), a sealing member 7 is disposed between the first protrusion 23a and the second protrusion 23b. In other words, the sealing member is inserted into the groove of the side member. Here, as shown in FIG. 6(b), let the end position of the sealing member 7 on the electrode laminate 6 side in the first direction X (the normal direction of the side surface on which the laminate member is disposed) be p1, the end position on the side opposite to p1 be p2, the end position of the side member 20 on the electrode laminate 6 side be q1, and the end position on the side opposite to q1 be q2. The end positions p1 and q1 may coincide. On the other hand, the end position q1 may be on the p2 side of p1 or on the electrode laminate 6 side of p1. Also, as shown in FIG. 6(b), it is preferable that the side member 20 is in surface contact with the surface SS of the sealing member 7 in the first direction X.

[0038] Also, in the present disclosure, one side member may be disposed for one laminate member, or two or more side members may be disposed, but the latter is preferable. In the latter case, for example, as shown in FIGS. 1(a) and (b), it is preferable that a pair of side members 20 (the first side member 20A and the second side member 20B) are disposed so as to face each other with respect to the laminate member 10. Also, as shown in FIGS. 1(a) and (b), it is preferable that the pair of side members 20 are disposed so as to face each other in the longitudinal direction (the first direction X) of the laminate member 10. On the other hand, although not particularly shown, the pair of side members may be disposed so as to face each other in the short side direction (the Y direction in FIG. 1) of the laminate member.

[0039] (3) Exterior body In the present disclosure, when the exterior body is viewed from the side member side in a side view of the battery, it is arranged to cover the surface constituting the outer edge of the side member and the surface constituting the outer edge of the laminated member. For example, as shown in FIGS. 1(b) and 6(a), when the side member 20 is arranged on the first side surface portion 10c or the second side surface portion 10d of the laminated member 10, the surfaces constituting the outer edge E3 of the laminated member 10 are the top surface portion 10a, the bottom surface portion 10b, the third side surface portion 10e, and the fourth side surface portion 10f. Further, the surfaces constituting the outer edge E4 of the side member 20 are the surface portions 20a, 20b, 20c, and 20d of the side member that respectively face the top surface portion 10a, the bottom surface portion 10b, the third side surface portion 10e, and the fourth side surface portion 10f of the laminated member.

[0040] The exterior body is preferably a laminate film. Further, the exterior body may be a single member composed of one laminate film, or may be a composite member composed of two laminate films. In the former case, as shown in FIG. 2(a), the laminated member and the side member can be covered by bending one laminate film. In the latter case, the laminated member and the side member can be covered by sandwiching the laminated member and the side member with two laminate films. Details of the laminate film will be described later.

[0041] Further, when the laminated member has the second current collector, as shown in FIG. 2, the exterior body 30 may have an exposed portion 31 where the second current collector is exposed in the thickness direction. When the exterior body has an exposed portion, the number of exposed portions may be 1 or 2, but the latter is preferable. This is because the second current collector can be exposed at the top surface portion and the bottom surface portion of the laminated member respectively, and current can be taken out through the second current collector.

[0042] FIG. 7 is a schematic cross-sectional view illustrating a battery in the present disclosure. As shown in FIG. 7(a), when the battery is viewed in cross-section from the thickness direction, the end position r of the exterior body 30 on the side member 20 side may be on the laminated member 10 side from the end position q2 of the side member 20 on the side opposite to the laminated member 10. q2 is as described above. That is, when the battery is viewed in plan from the thickness direction, the exterior body 30 may cover a part of the side member 20. In this case, a part of the side member 20 (the part not covered by the exterior body 30) is exposed. On the other hand, as shown in FIG. 7(b), the end position r of the exterior body 30 may coincide with the end position q2 of the laminated member 20, or may be outside the end position q2 as shown in FIG. 7(c). That is, when the battery is viewed in plan from the thickness direction, the exterior body 30 may cover the entire side member 20.

[0043] FIG. 8 is a schematic side view of the battery in the present disclosure viewed from the side member side. As shown in FIGS. 8 and 2(b), the battery 100 may have an end contact portion S where the ends of the exterior body 30 are welded together. As shown in FIGS. 2(b) and 8(a), when the exterior body is a single member (a single laminated film), usually, the battery 100 has one end contact portion S. On the other hand, when the exterior body is a composite member (two laminated films), as shown in FIGS. 8(b) to (d), usually, the battery 100 has two end contact portions S. As shown in FIG. 2(b), usually, the end contact portion is formed along the side surface of the laminated member where the side member is not arranged.

[0044] As shown in FIGS. 8(a) to 8(c), in the above side view, the end contact portion S may be formed to protrude from the side member 20 (and the laminated member). The surface where the end contact portion S protrudes in the battery may be the bottom surface of the laminated member as shown in FIGS. 8(a) and 8(b), or may be the side surface of the laminated member where the side member is not arranged as shown in FIG. 8(c). Although not particularly shown, the protruding end contact portion may be bent according to the shape of the side member because the surplus space can be reduced. On the other hand, as shown in FIG. 8(d), in the above side view, the end contact portion S may not protrude from the side member 20 (and the laminated member). In other words, the ends of the exterior body may be welded on the surfaces of the laminated member and the sealing member.

[0045] FIG. 9 is a schematic side view and a schematic perspective view illustrating the battery in the present disclosure. Specifically, FIG. 9(a) is a schematic side view of the battery viewed from the laminated member side, FIG. 9(b) is an enlarged schematic side view of the dotted line portion in FIG. 9(a), and FIG. 9(c) is an enlarged schematic perspective view of the dotted line portion in FIG. 9(a). As shown in FIG. 9(a), the battery 100 may have a welded portion T where the inner surfaces (the surfaces on the side member 20 side) of the exterior body 30 are welded on the side member 20. It is preferable that the welded surface in the welded portion T has no gap. By having the welded portion on the side member, a decrease in the sealing performance of the battery can be suppressed.

[0046] Further, as shown in FIGS. 9(b) and 9(c), the welded portion T is preferably formed at the corner of the outer edge E4 of the side member 20. In particular, it is preferable that the welded portion T is arranged at the corner constituting the outer edge E4 of the side member 20. Specifically, it is preferable that the corner constituting the outer edge E4 of the side member 20 coincides with the end t of the welded surface in the welded portion T. As shown in FIG. 9(b), let the width of the welded surface in the welded portion T be w. The width w is, for example, 0.1 mm or more, may be 0.3 mm or more, and may be 0.6 mm or more. On the other hand, the width w is, for example, 1.2 mm or less.

[0047] Further, as shown in FIG. 9(c), it is preferable that the welded portion T is formed along the extending direction of the side surface of the electrode laminate (not shown) where the side member 20 is not disposed (the first direction X in FIG. 9(b)).

[0048] 2. Battery members The battery in the present disclosure includes a laminated member having an electrode laminate and a sealing member, a side member, and an exterior body.

[0049] (1) Electrode laminate As described above, the electrode laminate in the present disclosure usually has a first current collector, an electrode layer (a positive electrode active material layer and a negative electrode active material layer), and a separator layer. Further, as described above, it may have a second current collector as necessary.

[0050] 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. Examples of the positive electrode active material include oxide active materials. Examples of the oxide active material include LiNi 1 / 3 Co 1 / 3 Mn 1 / 3 O 2 and other rock salt layer-type active materials, LiMn 2 O 4 and other spinel-type active materials, LiFePO 4 and other olivine-type active materials. Further, sulfur (S) may be used as the positive electrode active material. The shape of the positive electrode active material is, for example, particulate.

[0051] Examples of the conductive material include carbon materials. The electrolyte is preferably a liquid electrolyte (electrolyte solution). The electrolyte solution contains, for example, a supporting salt such as LiPF 6 and a solvent such as a carbonate-based solvent. Examples of the binder include rubber-based binders and fluoride-based binders.

[0052] The negative electrode active material layer contains at least a negative electrode active material. The negative electrode active material layer may further contain at least one of a conductive material, an electrolyte, and a binder. Examples of the negative electrode active material include metal active materials such as Li and Si, carbon active materials such as graphite, and oxide active materials such as Li 4 Ti 5 O 12 and the like. The shape of the negative electrode active material is, for example, particulate or foil-like. The conductive material, electrolyte, and binder are the same as those described above.

[0053] The separator is not particularly limited as long as it is a member through which the electrolytic solution can permeate, and a conventionally known member can be used.

[0054] The first current collector and the second current collector may be a positive electrode current collector or a negative electrode current collector. Examples of the material of the positive electrode current collector include metals such as aluminum, SUS, and nickel. Examples of the material of the negative electrode current collector include metals such as copper, SUS, and nickel.

[0055] (2) Sealing member The sealing member is a resin member. Examples of the resin include thermoplastic resins. Examples of the thermoplastic resin include olefin resins such as polyethylene and polypropylene.

[0056] (3) Side member The side member has a metal foil and a resin layer. The material of the metal foil is not particularly limited, and examples thereof include metals such as aluminum, SUS, and nickel. Also, examples of the material of the resin layer include the above-described thermoplastic resins.

[0057] (4) Outer package The exterior body in the present disclosure is preferably a laminated film having at least a structure in which a heat-sealing layer and a metal layer are laminated. Further, the laminated film may have a heat-sealing layer, a metal layer, and a resin layer in this order along the thickness direction. Examples of the material of the heat-sealing layer include olefin resins such as polypropylene (PP) and polyethylene (PE). Examples of the material of the metal layer include aluminum, aluminum alloy, and stainless steel. Examples of the material of the resin layer include polyethylene terephthalate (PET) and nylon. The thickness of the heat-sealing 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 resin layer is, for example, 20 μm or more and 60 μm or less. The thickness of the exterior body is, for example, 80 μm or more and 250 μm or less.

[0058] (5) Battery The battery in the present disclosure is typically a lithium-ion secondary battery. Further, the battery is preferably a liquid-based battery in which the above electrode laminate contains an electrolytic solution. Examples of the use of the battery include power sources for vehicles such as hybrid vehicles (HEV), plug-in hybrid vehicles (PHEV), electric vehicles (BEV), gasoline vehicles, and diesel vehicles. In particular, it is preferably used as a driving power source for hybrid vehicles (HEV), plug-in hybrid vehicles (PHEV), or electric vehicles (BEV). Further, the battery in the present disclosure may be used as a power source for moving bodies other than vehicles (for example, railways, ships, airplanes), and may also be used as a power source for electrical products such as information processing devices.

[0059] B. Manufacturing method of battery As shown in FIG. 10, the method for manufacturing a battery according to the present disclosure is the method for manufacturing a battery described above, and includes a preparation step of preparing the above-described laminated member and the above-described side member, and arranging the above-described side member on the above-described side surface of the above-described laminated member so that the above-described sealing member is disposed between the above-described first protrusion and the above-described second protrusion, an arranging step, a covering step of covering the above-described surface constituting the outer edge of the above-described side member and the above-described surface constituting the outer edge of the above-described laminated member with the above-described exterior body, and a welding step of heating a portion of the above-described exterior body covering the above-described side member to weld the above-described exterior body to the above-described first protrusion and the above-described second protrusion.

[0060] 1. Preparation step The preparation step in the present disclosure is a step of preparing the above-described laminated member and the above-described side member.

[0061] FIG. 11 is a schematic cross-sectional view illustrating a method of preparing a laminated member in the present disclosure. In particular, FIG. 11 shows a method of preparing a laminated member having a bipolar electrode and containing an electrolytic solution. First, as shown in FIG. 11(a), a bipolar electrode BP1 and a bipolar electrode BP2 are prepared. The bipolar electrode BP1 and the bipolar electrode BP2 each have frame members 7a and 7b for forming a sealing member disposed along the outer edge of the first current collector 1. Next, the negative electrode active material layer 3 in the bipolar electrode BP1 and the positive electrode active material layer 2 in the bipolar electrode BP2 are opposed to each other with a separator 4 interposed therebetween. At this time, at least a part of the outer edge of the separator 4 is disposed between the frame member 7a and the frame member 7b. Also, as shown in FIG. 11(a), a nested member α and a frame member (spacer) 7c are disposed between the frame member 7a in the bipolar electrode BP1 and the frame member 7b in the bipolar electrode BP2. Next, although not particularly shown, a positive electrode side end electrode CA and a negative electrode side end electrode AN are laminated, and a second current collector (positive electrode current collector) is laminated on the positive electrode side end electrode CA, and a second current collector (negative electrode current collector) is laminated on the negative electrode side end electrode AN. Then, by welding the plurality of laminated frame members, a structure having a nested member α as shown in FIG. 11(b) is obtained. Next, as shown in FIG. 11(c), a liquid injection frame 7d containing resin is provided around the nested member α, and then, by removing the nested member α, a through hole β penetrating the sealing member is formed. And although not particularly shown, an electrolytic solution is injected from the through hole, and after the injection, the liquid injection frame together with the through hole is sealed with resin. In this way, a laminated member 10 as shown in FIG. 3(b) is obtained. Thus, the sealing member in the present disclosure may include the above-described frame member and the liquid injection frame (liquid injection frame sealed with resin).

[0062] FIG. 12 is a schematic cross-sectional view illustrating a method of preparing a side member in the present disclosure. As shown in FIG. 12, the side member in the present disclosure can be prepared by injection molding. As shown in FIGS. 12(a) and (b), molds M1 and M2 are arranged to face each other. As shown in FIG. 12(a), a metal foil 21 is arranged in advance on one of the molds M1. Then, as shown in FIGS. 12(b) and (c), resin is injected. Thereafter, by removing the molds M1 and M2, a side member 20 as shown in FIGS. 4(a) and (b) is obtained. Although not shown, a metal foil may be post-attached to the injection-molded resin layer. By doing so, a side member as shown in FIGS. 4(c) and (d) is obtained.

[0063] 2. Arrangement step The arrangement step in the present disclosure is a step of arranging the side member on the side surface of the laminated member such that the sealing member is arranged between the first protrusion and the second protrusion. FIG. 13 is a schematic perspective view illustrating the arrangement step and the covering step in the present disclosure. As shown in FIGS. 13(a) and (b), first side members 20A and second side members 20B are arranged on the side surfaces (the first side surface 10c and the second side surface 10d) of the prepared laminated member 10, and the sealing member of the laminated member is inserted into the groove of the side member.

[0064] 3. Covering step The covering step in the present disclosure is a step of covering the surface constituting the outer edge of the side member and the surface constituting the outer edge of the laminated member with the exterior body. The surfaces constituting the outer edge of the side member and the outer edge of the laminated member are as described above. As shown in FIGS. 13(b) and (c), the structure V having the laminated member 10 and the side member 20 can be covered by winding one exterior body 30 around it. The exterior body is as described above. Also, in the covering step, the above-described end contact portion and welding portion may be formed. Note that the covering step is preferably performed in a reduced-pressure environment because the adhesion of the exterior body can be made better.

[0065] 4. Welding step The welding process in the present disclosure is a process of heating a portion of the exterior body covering the side member and welding the exterior body to the first protrusion and the second protrusion. Note that the welding process is preferably performed in a reduced-pressure environment, similar to the coating process.

[0066] In the welding process, a portion of the exterior body 30 covering the side member 20 as shown in FIG. 13(c) is heated. Therefore, there is no risk of directly heating the sealing member in the laminated member, and thermal deformation of the sealing member can be suppressed.

[0067] 5. Battery The battery manufactured by the above-described process is as described in "A. Battery".

[0068] Note that the present disclosure is not limited to the above-described embodiments. The above-described embodiments are examples, and any configuration that has substantially the same configuration as the technical idea described in the claims of the present disclosure and exhibits the same operational effects is included in the technical scope of the present disclosure.

Explanation of Reference Numerals

[0069] 1... First current collector 2... Positive electrode active material layer 3... Negative electrode active material layer 4... Separator 5... Second current collector E... Electrode U... Power generation unit 6... Electrode laminate 7... Sealing member 10... Laminated member 20... Side member 30... Exterior body 100... Battery

Claims

1. A laminated member having an electrode laminate including a plurality of electrodes laminated in a thickness direction, and a resin sealing member disposed along an outer edge of the electrode laminate, a side member disposed on a side surface portion of the laminated member, and an exterior body covering the laminated member and the side member, wherein the battery comprises: when the battery is viewed from the side member side in a side view, the exterior body is disposed so as to cover a surface constituting an outer edge of the side member and a surface constituting an outer edge of the laminated member, the side member has a metal foil and a resin layer disposed on one main surface of the metal foil, the resin layer has a first protrusion and a second protrusion extending in a first direction orthogonal to the thickness direction, the sealing member is disposed between the first protrusion and the second protrusion, and the first protrusion and the second protrusion are each welded to the exterior body. A battery.

2. The electrode has a first current collector and an electrode layer disposed on at least one surface of the first current collector in the thickness direction, the electrode laminate has a second current collector at an end portion in the thickness direction, and the exterior body has an exposed portion where the second current collector is exposed in the thickness direction. The battery according to claim 1.

3. The side member is in surface contact with a surface of the sealing member in the first direction. The battery according to claim 1.

4. The electrode laminate has a plurality of bipolar electrodes as the electrodes. The battery according to claim 1.

5. The battery is a liquid-based battery in which the electrode laminate contains an electrolytic solution. The battery according to claim 1.

6. A method for manufacturing a battery according to any one of claims 1 to 5, a preparation step of preparing the laminated member and the side member, an arrangement step of arranging the side member on the side surface portion of the laminated member so that the sealing member is disposed between the first protrusion and the second protrusion, a covering step of covering the surface constituting the outer edge of the side member and the surface constituting the outer edge of the laminated member with the exterior body, and a welding step of heating a portion of the exterior body covering the side member to weld the exterior body to the first protrusion and the second protrusion. A method for manufacturing a battery.

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