Method for manufacturing an electricity storage device and an electricity storage device

Abstract

To provide a manufacturing method of a power storage device in which molding failure is less likely occur when a resin member is molded.SOLUTION: A manufacturing method of a power storage device includes a preparation step of preparing a predetermined lamination member, a first arrangement step of arranging a predetermined first mold, a first molding step of obtaining a predetermined nest B, a second arrangement step of arranging a predetermined second mold, and a second molding step of molding a predetermined resin member.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to a manufacturing method for an electricity storage device and the electricity storage device. [Background technology]

[0002] In a method for manufacturing an electric storage device such as a secondary battery, a technique is known in which a seal member is formed along the outer edge of an electrode stack, and a resin member is further formed along the outer edge of the seal member. Also, a technique is known in which a through hole is formed by using a nest to pass through the seal member and the resin member.

[0003] For example, Patent Document 1 discloses an electricity storage device having a laminate including a bipolar electrode, a first seal portion arranged along the outer edge of the laminate, a second seal portion arranged along the outer edge of the first seal portion, and a through hole penetrating the first seal portion and the second seal portion. Patent Document 1 also discloses that a laminate member incorporating a nest (a member having the laminate and the first seal portion) is prepared, and then the second seal portion is formed by injection molding. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2019-16459 A Summary of the Invention [Problem to be solved by the invention]

[0005] When a resin component is molded by a resin molding method for a laminated component incorporating a nest, the nest is held and fixed by inserting a recess in the mold into the nest. If the nest and the recess in the mold interfere with each other when the recess in the mold is inserted into the nest, the nest may be damaged. Therefore, it is necessary to set the dimensions of the mold recess to a certain degree larger than the dimensions of the nest. On the other hand, if the dimensions of the mold recess are too large compared to the dimensions of the nest, resin may leak from the gap during molding, causing burrs.

[0006] In addition, the effect of misalignment of the insert is significantly larger in the width direction (y-axis direction). Therefore, it is necessary to set the dimensions of the mold recess relatively large in the width direction compared to the dimensions of the insert. As a result, molding defects such as burrs are significantly likely to occur.

[0007] The present disclosure has been made in consideration of the above-described circumstances, and has a primary object to provide a manufacturing method for an energy storage device that is less susceptible to molding defects when molding a resin member. [Means for solving the problem]

[0008] [1] a preparation step of preparing a laminated member including an electrode laminate including a plurality of electrodes laminated in a z-axis direction, a sealing member disposed along an outer edge of the electrode laminate as viewed from the z-axis direction, and a insert A having one end located inside the electrode laminate and the other end protruding outside the sealing member in an x-axis direction perpendicular to the z-axis direction; a first arrangement step of inserting the insert A protruding from the seal member in the laminated member into a first recess in a first mold; a first molding step of, after the first arrangement step, supplying a first resin between the insert A and the first recess to mold a resin part, thereby obtaining an insert B having the insert A and the resin part; a second arrangement step of inserting the insert B protruding from the seal member in the laminated member into a second recess in a second mold after the first molding step; a second molding step of molding a resin member by supplying a second resin between the laminated member and the second mold after the second arrangement step; having The method for manufacturing an electricity storage device, wherein the first recess and the second recess have the same length in a y-axis direction perpendicular to the z-axis direction and the x-axis direction.

[0009] [2] The method for manufacturing an electricity storage device according to [1], wherein when viewed from the z-axis direction, the insert B has the resin parts on both sides of the insert A in the y-axis direction.

[0010] [3] The method for manufacturing an electricity storage device according to [1] or [2], wherein, as viewed from the y-axis direction, the insert B has the resin parts on both sides of the insert A in the z-axis direction.

[0011] [4] The method for manufacturing an electricity storage device according to any one of [1] to [3], wherein the melting point of the first resin is higher than the melting point of the second resin.

[0012] [5] the sealing member is a resin member containing a third resin, the third resin and the second resin are olefin-based resins, The method for producing an electricity storage device according to any one of [1] to [4], wherein the first resin is a polyester resin.

[0013] [6] The manufacturing method for an energy storage device described in any of [1] to [5] includes a through hole forming process of forming a first through hole penetrating the sealing member and a second through hole penetrating the resin member by removing the insert B from the laminate member and the resin member after the second molding process.

[0014] [7] An electricity storage device having an electrode stack including a plurality of electrodes stacked in a z-axis direction, a sealing member disposed along an outer edge of the electrode stack as viewed from the z-axis direction, and a resin member disposed along an outer edge of the sealing member as viewed from the z-axis direction, the power storage device has a first through hole penetrating the sealing member in an x-axis direction perpendicular to the z-axis direction, and a second through hole communicating with the first through hole and penetrating the resin member, In the energy storage device, when a direction perpendicular to the x-axis direction and the z-axis direction is defined as a y-axis direction, the length of the second through hole in the y-axis direction is greater than the length of the first through hole in the y-axis direction.

[0015] [8] The power storage device according to [7], wherein a length of the second through hole in the z-axis direction is greater than a length of the first through hole in the z-axis direction.

[0016] [9] The power storage device according to [7] or [8], wherein a residual component of a first resin having a higher melting point than a second resin constituting the resin member is present on an inner wall portion of the second through hole. Effect of the Invention

[0017] The method for manufacturing an electricity storage device according to the present disclosure has the advantage that molding defects are less likely to occur when molding a resin member. [Brief description of the drawings]

[0018] [Figure 1] 1A to 1C are schematic perspective views illustrating a method for manufacturing an electricity storage device according to the present disclosure. [Diagram 2] 3A to 3C are schematic diagrams illustrating a first arrangement step and a first molding step in the present disclosure. [Diagram 3] 4A to 4C are schematic diagrams illustrating a second arrangement step and a second molding step in the present disclosure. [Figure 4] 1 is a schematic diagram illustrating a conventional resin molding method. [Diagram 5]1 is a schematic cross-sectional view illustrating an electrode according to the present disclosure. [Figure 6] 1 is a schematic cross-sectional view illustrating a laminated member according to the present disclosure. [Figure 7] 1A to 1C are schematic cross-sectional views illustrating a method for forming a laminate member in the present disclosure. [Figure 8] FIG. 2 is a schematic diagram illustrating a nest B in the present disclosure. [Figure 9] FIG. 2 is a schematic diagram illustrating a nest B in the present disclosure. [Figure 10] 4 is a schematic diagram illustrating an insert B and a through hole in the present disclosure. FIG. [Figure 11] 4 is a schematic diagram illustrating an insert B and a through hole in the present disclosure. FIG. [Figure 12] 1 is a schematic cross-sectional view illustrating an example of a power storage device according to the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019] Hereinafter, the embodiments of the present disclosure will be described in detail with reference to the drawings. Each of the drawings shown below is a schematic illustration, and the size and shape of each part are appropriately exaggerated to facilitate understanding. In addition, in this specification, when expressing an aspect in which another member is arranged relative to a certain member, the term "above" or "below" is used, unless otherwise specified, it includes both a case in which another member is arranged directly above or below a certain member so as to be in contact with the certain member, and a case in which another member is arranged above or below a certain member via another member.

[0020] A. Method for manufacturing an electricity storage device FIG. 1 is a schematic perspective view illustrating a method for manufacturing a power storage device according to the present disclosure. First, as shown in FIGS. 1(a) to 1(c), a laminate member 10 is prepared (preparation step). The laminate member 10 can be obtained, for example, by the following method. As shown in FIG. 1(a), an electrode E is prepared. The electrode E has a current collector 1, a positive electrode layer 2 disposed on one surface of the current collector 1, and a negative electrode layer (not shown) disposed on the other surface of the current collector 1. The electrode E also has a frame member 5 for forming a seal member along the outer edge of the current collector 1. Next, as shown in FIG. 1(b), a plurality of electrodes E are laminated in the z-axis direction to form an electrode laminate α. In addition, when a plurality of electrodes E are laminated in the z-axis direction, a nest A (nested γ a 1(c), the side surface SS5 of the frame members 5 stacked in the z-axis direction is heated to thermally weld the frame members 5 stacked in the z-axis direction. As a result, as shown in FIG. 1(c), the electrode stack α, the seal member β arranged along the outer edge of the electrode stack α when viewed from the z-axis direction, and the insert A (insert γ a ) and a laminated member 10 having the above structure is obtained.

[0021] Next, as shown in FIG. 1(d), insert piece A (not shown) protruding from seal member β in laminate member 10 is inserted into a first recess (not shown) in first mold 20 (first arrangement step). In this disclosure, a recess refers to a space into which a insert piece is inserted, and the recess may be a groove portion having a bottom or a hole portion without a bottom. A first resin is then supplied between insert piece A and the first recess to form a resin portion. This causes insert piece A (insert piece γ) to be inserted into first mold 20 as shown in FIG. 1(e). a ) and insert B having resin part γ1 (insert γ b ) is obtained (first molding step).

[0022] Here, the first arrangement step and the first molding step will be described in detail with reference to Fig. 2. As shown in Fig. 2(a) and (b), in the first arrangement step, the insert A (insert γ a) is inserted into the first recess 21 of the first mold 20. For example, the end face of the first mold 20 is aligned with the reference plane C, and the insert A (insert γ a 2(c) and (d), the position of the first recess 21 is adjusted relative to the insert A (insert γ a ) to resin part γ a By increasing the volume, nest B (nested γ b ) is obtained. b ) in the resin part γ a is nested A (nested γ a ) can absorb the effects of misalignment.

[0023] Next, as shown in FIG. 1( f ), the insert B (insert γ b ) is inserted into second recess 31 in second mold 30 (second placement step). Then, a second resin is supplied between laminate member 10 and second mold 30. This causes resin member 40 to be molded on the side surface of laminate member 10, as shown in FIG. 1(g) (second molding step).

[0024] Here, the second arrangement step and the second molding step will be described in detail with reference to Fig. 3. As shown in Fig. 3(a) and (b), the insert B (insert γ b ), and insert second recess 31 of second mold 30 into reference plane C. In the present disclosure, the first recess (e.g., first recess 21 in FIG. 3(b)) and second recess 31 have the same length in the y-axis direction. Furthermore, as shown in FIG. 3(b), for example, an end face of second mold 30 is aligned with reference plane C, and insert B (insert γ b The position of the second recess 31 with respect to the insert A (insert γ a 3(b), the position of the first recess 21 relative to the insert B (insert γ b ) and the second recess 31 in the second mold 30 can be positioned with high positional accuracy. As a result, as shown in FIG. bThis makes it possible to prevent resin from leaking into the gap between the first mold 30 and second mold 30, and thus the desired resin member 40 is formed.

[0025] According to the present disclosure, by producing nest B from nest A using a first mold, and then molding the resin member using a second mold having a second recess whose length in the y-axis direction is the same as that of the first recess, it is possible to suppress the occurrence of molding defects when molding the resin member.

[0026] 4 is a schematic diagram illustrating a conventional resin molding method. As shown in FIG. 4(a) and (b), a recess of the mold 50 is inserted into the nesting member γ protruding from the seal member β. As described above, when the recess of the mold 50 is inserted into the nesting member γ, if the nesting member γ and the recess of the mold 50 interfere with each other, the nesting member γ may be damaged. Therefore, it is necessary to set the dimensions of the recess of the mold 50 to be somewhat larger than the dimensions of the nesting member γ. On the other hand, if the dimensions of the recess of the mold 50 are too large compared to the dimensions of the nesting member γ, resin may leak from the gap during molding, resulting in burrs.

[0027] Generally, the width of the insert (length in the y-axis direction) is extremely large compared to the thickness of the insert (length in the z-axis direction). Therefore, the effect of misalignment of the insert is significantly large in the width direction (y-axis direction). Therefore, it is necessary to set the dimensions of the mold recess relatively large in the width direction compared to the dimensions of the insert. As a result, molding defects such as burrs are significantly likely to occur. Specifically, as shown in FIG. 4(c), resin leaks into the gap between the insert γ and the recess of the mold 50, and molding defects such as burrs are significantly likely to occur.

[0028] In contrast, in the present disclosure, as shown in Figures 2 and 3 above, a first mold is used to produce nest B from nest A, and the resin member is molded using a second mold having a second recess whose length in the y-axis direction is the same as that of the first recess, thereby making it possible to suppress the occurrence of molding defects when molding the resin member.

[0029] 1.Preparation process The preparation process in the present disclosure is a process of preparing a laminated member having an electrode stack including a plurality of electrodes stacked in the z-axis direction, a sealing member arranged along the outer edge of the electrode stack when viewed from the z-axis direction, and a nest A having one end located inside the electrode stack and the other end protruding outside the sealing member in the x-axis direction perpendicular to the z-axis direction.

[0030] (1) Electrode laminate The electrode laminate in the present disclosure includes a plurality of electrodes stacked in the z-axis direction. The electrode has a current collector and an electrode layer (positive electrode layer or negative electrode layer) disposed on at least one surface of the current collector. As shown in FIG. 5, the electrode E may be a bipolar electrode having a current collector 1, a positive electrode layer 2 disposed on one surface of the current collector 1, and a negative electrode layer 3 disposed on the other surface of the current collector 1.

[0031] As shown in FIG. 6, the electrode laminate α includes a plurality of electrodes E laminated in the z-axis direction (thickness direction). The electrode laminate α shown in FIG. 6 has a bipolar electrode BP1, a bipolar electrode BP2, a positive electrode end electrode CA, and a negative electrode end electrode AN as the electrodes E. The bipolar electrode BP1 and the bipolar electrode BP2 each have a current collector 1, a positive electrode layer 2 arranged on one surface of the current collector 1, and a negative electrode layer 3 arranged on the other surface of the current collector 1. The positive electrode end electrode CA has a current collector 1 and a positive electrode layer 2 arranged on one surface of the current collector 1. The negative electrode end electrode AN has a current collector 1 and a negative electrode layer 3 arranged on one surface of the current collector 1. In addition, the electrode laminate in the present disclosure is not particularly limited as long as it includes a plurality of electrodes E laminated in the z-axis direction, and may not have a bipolar electrode.

[0032] As shown in FIG. 6, the electrode stack α includes a power generation unit U (U1 to U3). The power generation unit U includes a positive electrode layer 2, a negative electrode layer 3, and a separator 4 disposed between the positive electrode layer 2 and the negative electrode layer 3. After the through-holes H illustrated in FIG. 1(h) are formed in the positive electrode layer 2, the negative electrode layer 3, and the separator 4, an electrolyte is supplied through the through-holes H. As a result, the positive electrode layer 2, the negative electrode layer 3, and the separator 4 are each impregnated with the electrolyte. The electrode stack in the present disclosure may include one power generation unit, or may include two or more power generation units.

[0033] The electrode stack α shown in FIG. 6 has a plurality of generating units (U1, U2, U3) stacked in the z-axis direction. As shown in FIG. 6, the plurality of generating units may be directly connected to each other. Although not specifically shown, the plurality of generating units may be connected in parallel to each other. The plurality of generating units are independent of each other so that the electrolyte does not flow between them. In FIG. 6, the plurality of generating units U1 to U3 are independent of each other so that the electrolyte does not flow between them. For example, the generating unit U1 and the generating unit U2 are partitioned by the current collector 1 and the sealing member β and are independent of each other.

[0034] One generating unit may be constructed using two bipolar electrodes. In FIG. 6, the electrode stack α has a bipolar electrode BP1 and a bipolar electrode BP2 in the z-axis direction. A separator 4 is disposed between the adjacent bipolar electrodes BP1 and BP2. The generating unit U2 is constructed from a positive electrode layer 2 in the bipolar electrode BP2, a negative electrode layer 3 in the bipolar electrode BP1, and a separator 4 disposed therebetween. On the other hand, the generating unit U1 is constructed from a positive electrode layer 2 in the bipolar electrode BP1, a negative electrode layer 3 in the negative electrode end electrode AN, and a separator 4 disposed therebetween. In addition, the generating unit U3 is constructed from a negative electrode layer 3 in the bipolar electrode BP2, a positive electrode layer 2 in the positive electrode end electrode CA, and a separator 4 disposed therebetween.

[0035] The planar shape of the electrode laminate in the present disclosure (shape as viewed from the z-axis direction) is not particularly limited, but examples thereof include quadrangles such as squares and rectangles. The length of one side of the planar shape of the electrode laminate is, for example, 30 cm or more, may be 50 cm or more, or may be 100 cm or more. On the other hand, the length of one side is, for example, 200 cm or less.

[0036] (2) Sealing material The sealing member in the present disclosure is disposed along the outer edge of the electrode laminate when viewed from the z-axis direction. The sealing member is usually disposed on the side of the electrode laminate. The side of the electrode laminate refers to a surface of the electrode laminate that extends in the z-axis direction. In addition, the side of the electrode laminate is usually a surface that connects the top surface (one main surface) and the bottom surface (the other main surface) of the electrode laminate, which are opposed to each other in the z-axis direction.

[0037] When viewed from the z-axis direction, the sealing member is preferably arranged in a frame shape along the outer edge of the current collector in the electrode laminate. For example, in FIG. 1(a), a frame-shaped sealing member β is arranged along the entire outer edge of the current collector 1. The sealing member is preferably a resin member. Examples of the resin (referred to as the third resin) constituting the sealing member include thermoplastic resins. Examples of the thermoplastic resin include olefin-based resins such as polyethylene and polypropylene, and polyester-based resins such as polyethylene terephthalate. Among them, the third resin is preferably an olefin-based resin.

[0038] (3) Nested A In the present disclosure, in the x-axis direction perpendicular to the z-axis direction, one end of the insert A is located inside the electrode stack, and the other end protrudes outside the seal member. As shown in FIG. 6, in the x-axis direction, the insert A (insert γ a ) is located inside the electrode laminate α, and one end t1 of the insert A (insert γ a The other end t2 of the sealing member β protrudes to the outside.

[0039] The inside of the electrode laminate α refers to the region on the central side of the electrode laminate α, based on the side (inner side SS1) of the sealing member β on the electrode laminate α side, when viewed from the z-axis direction. The outside of the sealing member β refers to the region on the opposite side of the electrode laminate α, based on the side (outer side SS1) of the sealing member β on the opposite side of the electrode laminate α, when viewed from the z-axis direction. In addition, it is preferable that the extension direction of the insert A (the direction connecting one end t1 and the other end t2) is parallel to the x-axis direction. Parallel means that the angle between the two directions is 30° or less. The insert A is a part of a mold, and is attached to a mother die such as a first mold, and is a member for producing a resin molded product.

[0040] As shown in Figure 6, nest A (nested γ a ) is fixed by the seal member β, and the insert A (insert γ a ) is exposed from the seal member β. In addition, the seal member β is restrained in the z-axis direction by a restraining portion (not shown), so that the insert A (inserted a ) is fixed and held by upper and lower seal members β in the z-axis direction. The insert A is made of, for example, a metal. The thickness (length in the z-axis direction) of the insert A is not particularly limited, but is, for example, 0.1 mm or more and 0.4 mm or less. In addition, the planar shape of the insert A (shape as viewed from the z-axis direction) is not particularly limited, but examples include quadrangles such as a square and a rectangle.

[0041] (4) Laminated materials 7 is a schematic cross-sectional view (exploded view) illustrating a method for forming a laminated member in the present disclosure. As shown in FIG. 7, a bipolar electrode BP1 and a bipolar electrode BP2 are prepared. The bipolar electrode BP1 has a positive electrode layer 2 disposed on one surface of a current collector 1 and a negative electrode layer 3 disposed on the other surface of the current collector 1.

[0042] Furthermore, the bipolar electrode BP1 has a frame member 5a for forming a seal member, which is disposed along the outer edge of the current collector 1. When viewed from the z-axis direction, the frame member 5a is usually disposed along the entire outer edge of the current collector 1. For example, when the outer edge of the current collector 1 has a rectangular shape, the frame member 5a is disposed along the entire outer edge of the rectangle. As shown in FIG. 7, the frame member 5a preferably covers a part of one main surface p of the current collector 1, a part of the other main surface q of the current collector 1, and the entire side surface r constituting the outer edge of the current collector 1.

[0043] 7, the bipolar electrode BP2 has a positive electrode layer 2 disposed on one surface of the current collector 1 and a negative electrode layer 3 disposed on the other surface of the current collector 1. Furthermore, the bipolar electrode BP2 has a frame member 5b for forming a seal member disposed along the outer edge of the current collector 1. Details of the bipolar electrode BP2 are similar to those of the bipolar electrode BP1 described above.

[0044] As shown in FIG. 7, the negative electrode layer 3 of the bipolar electrode BP1 and the positive electrode layer 2 of 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 5a and the frame member 5b. Also, as shown in FIG. 7, a nest A (nested γ a ) and frame member (spacer) 5c are placed. Next, although not shown, the positive end electrode CA and the negative end electrode AN are also laminated in the same manner as in FIG. 6. Thereafter, the laminated frame members are welded together to form a seal member. In this manner, a laminated member is obtained.

[0045] 2.First placement process A first arrangement step in the present disclosure is a step of inserting the insert A protruding from the seal member in the laminate member into a first recess in a first mold.

[0046] As shown in FIG. 2(b), the insert A (insert γ a) is inserted into the first recess 21 of the first mold 20. a 2(b), a space is provided around the first mold 20 for molding a resin portion (not shown). The first recess 21 in the first mold 20 is preferably a groove portion having a bottom 21a. This is because a resin portion having a desired shape is easily formed. Also, as shown in FIG. 2(b), the position of the first recess 21 in the y-axis direction is adjusted and the first mold 20 is arranged. The method for adjusting the position of the first recess 21 is not particularly limited, but for example, as shown in FIG. 2(b), a method of adjusting the position of the first recess 21 by aligning the end face of the first mold 20 with a reference plane C (a plane extending in the x-axis direction) can be mentioned. By using the plane extending in the x-axis direction as the reference plane, it is possible to effectively prevent positional deviation in the y-axis direction.

[0047] 3.First molding process The first molding process in the present disclosure is a process of molding a resin part by supplying a first resin between the insert A and the first recess after the first placement process, thereby obtaining an insert B having the insert A and the resin part.

[0048] The method for molding the resin part is not particularly limited, and examples thereof include resin molding methods such as injection molding. Examples of the first resin constituting the resin part include thermoplastic resins. Examples of the thermoplastic resin include olefin-based resins such as polyethylene and polypropylene, and polyester-based resins such as polyethylene terephthalate. Among them, it is preferable that the first resin is a polyester-based resin.

[0049] Melting point T of the first resin that constitutes the resin part M1 is the melting point T of the second resin constituting the resin member described later. M2 It is preferable that the thickness is higher than the thickness of the resin member, because this can prevent the first resin from melting during molding of the resin member. M1 and T M2 The difference is, for example, 20° C. or more, may be 50° C. or more, or may be 100° C. or more.

[0050] It is preferable that the first resin constituting the resin portion and the second resin constituting the resin member described below have low compatibility. This is because the low compatibility between the first resin and the second resin makes it easier to remove the insert B. Specifically, it is preferable that the first resin is a polyester-based resin and the second resin is an olefin-based resin.

[0051] It is preferable that the first resin constituting the resin portion and the third resin constituting the above-mentioned sealing member have low compatibility. This is because the low compatibility between the first resin and the third resin makes it easier to remove the insert B. Specifically, it is preferable that the first resin is a polyester-based resin and the third resin is an olefin-based resin.

[0052] 8(a) to (d) are schematic diagrams illustrating the insert B in the present disclosure. Specifically, they are schematic diagrams obtained by cutting the center of the insert B in the z-axis direction with the xy plane. As shown in Figs. 8(a) to (d), when viewed from the z-axis direction, the insert B (insert γ b ) is the nest A (nested γ a ) on both sides of the insert A (insert γ a It is preferable that the resin portion γ1 is disposed so as to sandwich the resin portion γ1.

[0053] As shown in Fig. 8(a), nest A (nested γ a ) is W1, and the width (length in the y-axis direction) of nest B (nested γ b The width of the gap 14 is defined as W2. The ratio of W2 to W1 (W2 / W1) is, for example, 1.1 or more, and may be 1.5 or more. On the other hand, W2 / W1 is, for example, 3.0 or less.

[0054] As shown in Fig. 8(a), nest A (nested γ a 8(b) to (d), the resin part γ1 may be disposed so as to cover the other end t2 of the insert A (insertion γ a) may be exposed from the resin part γ1. Also, as shown in FIG. 8(b), the position of the other end t2 may coincide with the position of the end of the resin part γ1 in the x-axis direction. Also, as shown in FIG. 8(c), the position of the end of the resin part γ1 may protrude from the position of the other end t2 in the x-axis direction. Also, as shown in FIG. 8(d), the position of the other end t2 may protrude from the position of the end of the resin part γ1 in the x-axis direction.

[0055] 9(a) to 9(c) are schematic cross-sectional views illustrating an example of the insert B in the present disclosure. Specifically, they are schematic diagrams obtained by cutting the center of the insert B in the y-axis direction with the xz plane. As shown in FIG. 9(a), when viewed from the y-axis direction, the insert B (insert γ b ) is the nest A (nested γ a ) may have resin parts γ1 on both sides. a 9B, the resin portion γ1 may be disposed on both sides (both sides normal to the z-axis direction) of the insert B (insert γ b ) is the nest A (nested γ a ) may have a resin portion γ1 on one side. a 9(c), the resin part γ1 may be disposed on only one surface (one of the surfaces normal to the z-axis direction) of the resin part γ1. Also, as shown in FIG. 9(c), the resin part γ1 does not have to be disposed on the surface normal to the z-axis direction.

[0056] As shown in Fig. 9(a), nest A (nested γ a ) is T1, and the thickness (length in the z-axis direction) of insert B (insert γ b ) is defined as T2. The ratio of T2 to T1 (T2 / T1) is, for example, 1.0 or more, and may be 1.5 or more. Meanwhile, T2 / T1 is, for example, 3.0 or less. The shape of the insert B in a plan view (shape when viewed from the z-axis direction) is not particularly limited, but examples thereof include quadrilaterals such as a square or a rectangle.

[0057] 4.Second placement process The second arrangement step in the present disclosure is a step of inserting the insert B protruding from the seal member in the laminated member into the second recess in the second mold after the first molding step. Also, in the present disclosure, the first recess and the second recess have the same length in the y-axis direction.

[0058] "The first recess and the second recess have the same length in the y-axis direction" means that they are the same to the extent that resin leakage does not occur during molding. The difference in length between the two is, for example, 1 mm or less, may be 0.5 mm or less, or may be 0.1 mm or less. Even if the first recess and the second recess have the same length in the y-axis direction, it is preferable that the length of the second recess in the y-axis direction is slightly longer than the length of the first recess in the y-axis direction. This is because interference between the insert B and the second recess can be prevented. The difference between the two may be, for example, 0.005 mm or more, or may be 0.01 mm or more.

[0059] As shown in FIG. 3(a), the insert B (insert γ b ) is inserted into the second recess 31 of the second mold 30. b ) and second mold 30, a space for molding resin member 40 is provided between second mold 30 and insert B (insert γ b ) into the second recess 31, the insert B (insert γ b) is held and fixed by the second recess 31. The second recess 31 in the second mold 30 is a hole without a bottom. On the other hand, although not particularly shown, the second recess 31 may be a groove with a bottom. Also, as shown in FIG. 3(b), the position of the second recess 31 in the y-axis direction is adjusted to position the second mold 30. The method for adjusting the position of the second recess 31 is not particularly limited, but for example, as shown in FIG. 3(b), a method of adjusting the position of the second recess 31 by aligning the end face of the second mold 30 with a reference plane C (a plane extending in the x-axis direction) can be mentioned. It is preferable that the adjustment of the position of the second recess 31 in the second arrangement step and the adjustment of the position of the first recess 21 in the first arrangement step are based on the same reference.

[0060] 5.Second molding process The second molding step in the present disclosure is a step of molding a resin member by supplying a second resin between the laminate member and the second mold after the second arrangement step. The resin member is a member for sealing the electrode laminate, similar to the above-mentioned sealing member.

[0061] The method for molding the resin member is not particularly limited, and examples thereof include resin molding methods such as injection molding. Examples of the second resin constituting the resin member include thermoplastic resins. Examples of the thermoplastic resin include olefin-based resins such as polyethylene and polypropylene, and polyester-based resins such as polyethylene terephthalate. Among them, it is preferable that the second resin is an olefin-based resin.

[0062] It is preferable that the second resin constituting the resin member and the third resin constituting the above-mentioned seal member have high compatibility. This is because the high compatibility between the second resin and the third resin increases the adhesion between the resin member and the seal member. Specifically, it is preferable that the second resin and the third resin are olefin-based resins.

[0063] The resin member is disposed along the outer edge of the laminated member. The resin member may be disposed along at least a part of the outer edge of the laminated member, or may be disposed along the entire outer edge of the laminated member. The resin member may have a partition structure on a side surface (the side surface opposite to the side surface on the sealing member side) that divides each of the nesting members B.

[0064] 6.Other processes The manufacturing method of the electricity storage device according to the present disclosure may include a through hole forming step of forming a first through hole penetrating the sealing member and a second through hole penetrating the resin member by removing the insert B from the laminated member and the resin member. Specifically, as shown in FIG. 1(h), after the second molding step, insert B (insert γ b 10(a), (b) and 11(a), (b), a through hole H is formed that has a first through hole H1 that passes through the seal member β and a second through hole H2 that communicates with the first through hole H1 and passes through the resin member 40.

[0065] As shown in Fig. 10(a) and (b), nest A (nested γ a It is preferable that the width W1 of the first through hole H1 is the same as the width W3 of the first through hole H1. b It is preferable that the width W2 of the second through hole H2 is the same as the width W4 of the second through hole H2. The preferable range of the ratio of W4 to W3 (W4 / W3) is the same as the above-mentioned W2 / W1.

[0066] As shown in Fig. 11(a) and (b), nest A (nested γ a It is preferable that the thickness T1 of the insert B (insert γ b It is preferable that the thickness T2 of the second through hole H2 in the z-axis direction is the same as the length T4 of the second through hole H2 in the z-axis direction. The preferable range of the ratio of T4 to T3 (T4 / T3) is the same as the above-mentioned T2 / T1.

[0067] Furthermore, in the through hole forming process, when insert B is removed, the first resin constituting the resin portion of insert B remains as a residual component on the inner wall of the second through hole due to friction. That is, after insert B is removed, a residual component of the first resin may be present on the inner wall of the second through hole. As described above, the first resin preferably has a higher melting point than the second resin constituting the resin member. Furthermore, a residual component of the first resin may be present on the inner wall of the second through hole, and the residual component may not be present on the inner wall of the first through hole.

[0068] The method for producing an electricity storage device according to the present disclosure may include, after the through-hole forming step, a step of supplying an electrolyte solution to the inside of the electrode stack through the through-hole. The method for supplying the electrolyte solution is not particularly limited, and a known method may be used.

[0069] The method for producing the electricity storage device in the present disclosure may include a sealing step of sealing the through-holes after the electrolyte supplying step. The method for sealing the through-holes is not particularly limited, and may be, for example, a method of sealing using a film. The electricity storage device obtained by each of the steps described above will be described later in "B. Electricity storage device".

[0070] B. Power storage device FIG. 12 is a schematic cross-sectional view illustrating an example of a power storage device according to the present disclosure. The power storage device 100 shown in FIG. 12 has an electrode stack α including a plurality of electrodes stacked in the z-axis direction, a seal member β arranged along the outer edge of the electrode stack α as viewed from the z-axis direction, and a resin member 40 arranged along the outer edge of the seal member as viewed from the z-axis direction. The power storage device 100 has a first through hole H1 penetrating the seal member β in the x-axis direction, and a second through hole H2 communicating with the first through hole H1 and penetrating the resin member 40. In addition, as shown in FIG. 10(b), the width W4 (length in the y-axis direction) of the second through hole H2 is larger than the width W3 (length in the y-axis direction) of the first through hole H1.

[0071] Each member constituting the electricity storage device of the present disclosure is the same as that described above in "A. Manufacturing method of electricity storage device". In addition, the electricity storage device of the present disclosure preferably has an electrolyte solution inside the electrode stack. In addition, as shown in FIG. 12, the second through hole H2 may be sealed with a film 60 arranged on a side surface of the resin member 40 (the side surface opposite to the side surface on the sealing member β side).

[0072] Specific examples of the power storage device in the present disclosure include secondary batteries (e.g., lithium ion secondary batteries) and electric double layer capacitors. In addition, applications of the power storage device include, for example, power sources for vehicles such as hybrid electric vehicles (HEVs), plug-in hybrid electric vehicles (PHEVs), electric vehicles (BEVs), gasoline automobiles, and diesel automobiles. In particular, it is preferable to use the power storage device as a driving power source for hybrid electric vehicles (HEVs), plug-in hybrid electric vehicles (PHEVs), or electric vehicles (BEVs). In addition, the power storage device in the present disclosure may be used as a power source for moving bodies other than vehicles (e.g., railways, ships, and aircraft), and may be used as a power source for electrical products such as information processing devices.

[0073] The present disclosure is not limited to the above-described embodiments. The above-described embodiments are merely examples, and anything that has substantially the same configuration as the technical idea described in the claims of the present disclosure and exhibits similar effects is included in the technical scope of the present disclosure. [Explanation of symbols]

[0074] 1...Current collector 2…Positive electrode layer 3...Negative electrode layer 4…Separator 5...Frame member 10...Laminated material 20…First mold 30…Second mold 40…Resin material 100...Electricity storage device

Claims

1. a preparation step of preparing a laminated member including an electrode stack including a plurality of electrodes stacked in a z-axis direction, a sealing member disposed along an outer edge of the electrode stack as viewed from the z-axis direction, and a insert A having one end located inside the electrode stack and the other end protruding outside the sealing member in an x-axis direction perpendicular to the z-axis direction; a first arrangement step of inserting the insert A protruding from the seal member in the laminated member into a first recess in a first mold; a first molding step of supplying a first resin between the insert A and the first recess after the first arrangement step to mold a resin part, thereby obtaining an insert B having the insert A and the resin part; a second arrangement step of inserting the insert B protruding from the seal member in the laminated member into a second recess in a second mold after the first molding step; a second molding step of molding a resin member by supplying a second resin between the laminated member and the second mold after the second arrangement step; having The method for manufacturing an energy storage device, wherein the first recess and the second recess have the same length in a y-axis direction perpendicular to the z-axis direction and the x-axis direction.

2. The method for manufacturing an energy storage device according to claim 1 , wherein when viewed from the z-axis direction, the insert B has the resin portion on both sides of the insert A in the y-axis direction.

3. The method for manufacturing an energy storage device according to claim 1 , wherein when viewed from the y-axis direction, the insert B has the resin portion on both sides of the insert A in the z-axis direction.

4. The method for manufacturing an electricity storage device according to claim 1 , wherein a melting point of the first resin is higher than a melting point of the second resin.

5. the sealing member is a resin member containing a third resin, the third resin and the second resin are olefin-based resins, The method for producing an electricity storage device according to claim 1 , wherein the first resin is a polyester resin.

6. 2. The method for manufacturing an energy storage device according to claim 1, further comprising a through hole forming step of forming a first through hole penetrating the sealing member and a second through hole penetrating the resin member by removing the insert B from the laminate member and the resin member after the second molding step.

7. An electric storage device including: an electrode stack including a plurality of electrodes stacked in a z-axis direction; a seal member disposed along an outer edge of the electrode stack as viewed from the z-axis direction; and a resin member disposed along an outer edge of the seal member as viewed from the z-axis direction, The energy storage device has a first through hole penetrating the seal member in an x-axis direction perpendicular to the z-axis direction, and a second through hole communicating with the first through hole and penetrating the resin member, An energy storage device, wherein, when a direction perpendicular to the x-axis direction and the z-axis direction is defined as a y-axis direction, the length of the second through hole in the y-axis direction is greater than the length of the first through hole in the y-axis direction.

8. The power storage device according to claim 7 , wherein a length of the second through hole in the z-axis direction is greater than a length of the first through hole in the z-axis direction.

9. The power storage device according to claim 7 , wherein a residual component of a first resin having a higher melting point than a second resin constituting the resin member is present on an inner wall of the second through hole.

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