Method for removing insert and method for manufacturing energy storage module

Abstract

To provide a method for extracting an insert that can suppress deformation or breakage of the insert due to a pin when the insert is extracted from an electrode member.SOLUTION: A method for extracting an insert from a specific electrode member includes a first restricting step, a second restricting step, and an extracting step, and the block used when extracting the insert has an integral structure.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to a nest extraction method and a manufacturing method for an energy storage module. [Background technology]

[0002] In a manufacturing method of a storage module such as a secondary battery, a technique of forming a seal member so as to surround an electrode stack is known. For example, Patent Document 1 discloses a storage module including an electrode stack and a seal member surrounding the electrode stack. Patent Document 2 discloses a method of preparing an electrode stack incorporating a through-hole forming member (insert), then forming a resin cylinder by injection molding, and then forming a through hole by pulling out the through-hole forming member. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2021-22534 [Patent Document 2] JP 2020-145113 A Summary of the Invention [Problem to be solved by the invention]

[0004] As a method for producing an electrode member having an electrode laminate, a seal member, and a insert, and for removing the insert from the produced electrode member, for example, a method is envisaged in which a pin is inserted into a through hole provided in the insert, and the inserted pin is moved away from the electrode laminate to remove the insert from the electrode member. Because the insert is thin, deformation or breakage of the insert may occur around the through hole due to the pin when the pin is moved away from the electrode laminate.

[0005] The present disclosure has been made in consideration of the above-mentioned circumstances, and provides a method for extracting a insert that can suppress deformation or breakage of the insert due to a pin when extracting the insert from an electrode member. [Means for solving the problem]

[0006] [1] A method for extracting a nest, comprising the steps of: The method is a method of pulling out the insert from an electrode member having an electrode stack in which a plurality of electrodes are stacked in a thickness direction, a seal member arranged to surround the electrode stack, and the insert arranged to penetrate the seal member in a first direction perpendicular to the thickness direction, with one end located inside the electrode stack and the other end located outside the seal member, The above method is a first limiting step of using a block having a slit portion, bringing the slit portion of the block close to the insert positioned outside the seal member from the first direction, inserting the insert into the slit portion, and limiting relative movement of the insert and the block in the thickness direction; a second limiting step of inserting a pin into the block with the insert inserted therein from the thickness direction to limit relative movement of the insert and the block in the first direction; a pulling out step of pulling out the insert from the electrode member by moving the insert and the block away from the electrode stack in the first direction after the second restricting step; having the insert has a through hole into which the pin can be inserted, the block has a recess into which the pin can be inserted at a position overlapping with the through hole as viewed from the thickness direction in a state in which the insert is inserted, In the second limiting step, the pin is inserted into the through hole and the recess to limit the relative movement in the first direction; The block has an integral structure.

[0007] [2] The material of the block is resin, rubber or metal.

[0008] [3] The thickness of the insert is 0.5 mm or less. The method for extracting a insert according to [1] or [2], wherein the length of the slit portion in the thickness direction is 1.0 times or more and 3.0 times or less the thickness of the insert.

[0009] [4] The method for extracting a core insert according to any one of [1] to [3], wherein the electrode stack has a bipolar electrode as the electrode.

[0010] [5] A method for manufacturing an energy storage module, comprising the steps of: extracting the insert from the electrode member by using the insert extraction method according to any one of [1] to [4]; and forming a through hole in the electrode member. Effect of the Invention

[0011] The method of extracting the insert in the present disclosure has the effect of suppressing deformation or breakage of the insert due to the pin when the insert is extracted from the electrode member. [Brief description of the drawings]

[0012] [Figure 1] 1A and 1B are a schematic plan view and a schematic cross-sectional view illustrating an electrode member according to the present disclosure. [Diagram 2] 1A and 1B are a schematic perspective view and a schematic plan view for explaining problems and effects of the present disclosure. [Diagram 3] 1A and 1B are a schematic plan view and a schematic cross-sectional view illustrating a first limiting step in the present disclosure. [Figure 4] 1A and 1B are schematic plan and cross-sectional views illustrating a block according to the present disclosure. [Diagram 5] 1A and 1B are a schematic plan view and a schematic cross-sectional view illustrating a second limiting step in the present disclosure. [Figure 6] FIG. 4 is a flow diagram illustrating a method for manufacturing an energy storage module according to the present disclosure. [Figure 7]1A to 1C are schematic cross-sectional views illustrating a preparation step in the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] The method for extracting the nesting member and the method for manufacturing the energy storage module according to the present disclosure will be described in detail below 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.

[0014] A. How to remove the nest First, the electrode member in the present disclosure will be described. Fig. 1(a) is a schematic plan view illustrating the electrode member in the present disclosure, and Fig. 1(b) is a cross-sectional view taken along the line AA in Fig. 1(a). As shown in Figs. 1(a) and 1(b), the electrode member 10 has a plurality of electrodes E arranged in a thickness direction D. T the electrode laminate EL laminated in the thickness direction D; the seal member 5 disposed so as to surround the electrode laminate EL; T and a insert 6 disposed so as to penetrate the seal member 5 in a first direction D1 perpendicular to the electrode stack EL, with one end t1 located inside the electrode stack EL and the other end t2 located outside the seal member 5.

[0015] As a method for extracting the insert 6 from the electrode member 10, for example, the methods shown in Fig. 2(a) to (c) are assumed. Fig. 2(a) is a schematic perspective view illustrating a conventional method for extracting the insert, Fig. 2(b) is a schematic plan view of the insert 6 shown in Fig. 2(a), and Fig. 2(c) is a cross-sectional view taken along the line AA in Fig. 2(b). As shown in Fig. 2(a), a method is assumed in which the insert 6 having a through hole H in a region protruding from the seal member 5 in the electrode member 10 is used, a pin P is inserted into the through hole H, and the inserted pin P is moved away from the electrode laminate EL to extract the insert 6 from the electrode member 10. Since the insert 6 is thin, as shown in Figs. 2(b) and (c), deformation or breakage of the insert 6 by the pin P may occur around the through hole H when the pin P is moved away from the electrode laminate (not shown).

[0016] In response to this, according to the present disclosure, as shown in FIG. 2(d), by using a block 11 in addition to the pin P and by placing the pin P and the block 11 away from the electrode stack (not shown), it is possible to suppress the occurrence of deformation or breakage of the insert 6. Specifically, the block 11 prevents the insert 6 from being deformed or broken in the thickness direction D. T By restricting the relative movement of the insert 6 and the block 11 in the thickness direction D when the pin P and the block 11 are moved away from the electrode stack (not shown), T In addition, the deformation of the insert 6 in the thickness direction D T By suppressing deformation of the insert 6 during the insertion, breakage of the insert 6 can be prevented. By suppressing deformation of the insert 6, the life of the insert 6 can be extended. Furthermore, if breakage occurs in the insert 6, the insert 6 cannot be pulled out from the electrode member (not shown), resulting in defective products. Therefore, by suppressing breakage of the insert 6, the occurrence of defective products can be suppressed.

[0017] Furthermore, when reducing the total thickness of the energy storage module, it is necessary to make the thickness of the nest thinner than before. When the thickness of the nest is thin, deformation or breakage of the nest due to the pins is particularly likely to occur. According to the present disclosure, by using blocks in addition to pins, deformation or breakage of the nest due to the pins can be suppressed even when the thickness of the nest is thin.

[0018] In addition, the block in the present disclosure has an integral structure. As will be described in detail later, the number of components of the block can be reduced, for example, compared to a block having a divided structure. In addition, in the case of a block having a divided structure, it is necessary to accurately position each through hole in the divided components, but in the case of a block having an integral structure, there is an advantage that the above positioning is not necessary.

[0019] 1. First restriction step The first limiting step in the present disclosure is a step of using a block having a slit portion, bringing the slit portion in the block close to the nest located outside the sealing member from the first direction, inserting the nest into the slit portion, and limiting the relative movement of the nest and the block in the thickness direction.

[0020] 3(a) is a schematic plan view illustrating the first limiting step in the present disclosure, showing a state before the insert piece 6 is inserted into the block 11, and FIG. 3(b) is a cross-sectional view taken along line AA in FIG. 3(a). FIG. 3(c) is a schematic plan view illustrating the first limiting step in the present disclosure, showing a state after the insert piece 6 is inserted into the block 11, and FIG. 3(d) is a cross-sectional view taken along line AA in FIG. 3(c). As shown in FIGS. 3(a) to 3(d), in the first limiting step, a block 11 having a slit portion S is used, and the slit portion S in the block 11 is brought close to the insert piece 6 positioned outside the seal member (not shown) in a first direction D1, the insert piece 6 is inserted into the slit portion S, and the block 11 is rotated in a direction parallel to the thickness direction D2. T This limits the relative movement of the nest 6 and the block 11 in the

[0021] 3(a) to (d), the insert 6 has a through hole H into which a pin (not shown) can be inserted. T The shape of the through hole H as viewed from the top (shape in plan view) is not particularly limited, but may be, for example, a circle, an ellipse, or a polygon (for example, a rectangle). T In the case where there are multiple nests 6,T From the perspective, it is preferable that the multiple through holes H overlap. The thickness of the insert 6 is designated as T6. T6 is not particularly limited, but may be, for example, 0.5 mm or less, or 0.4 mm or less. On the other hand, T6 is, for example, 0.05 mm or more.

[0022] The shape of the nest as viewed in the thickness direction (shape in plan view) is not particularly limited, but may be, for example, a quadrangle such as a rectangle. The length of each side constituting the shape in plan view of the nest is not particularly limited, but may be, for example, 20 mm or more, and may be 30 mm or more. The length of each side is, for example, 100 mm or less. For example, when the shape of the nest as viewed in plan view is rectangular, the length of the short side is, for example, 20 mm or more and 50 mm or less, and the length of the long side is, for example, 50 mm or more and 100 mm or less. When the shape of the nest as viewed in plan view is rectangular, the nest in the electrode member is usually arranged so that the long side is along the first direction.

[0023] As shown in FIGS. 3(c) and 3(d), the block 11 has a thickness direction D T 3(d) has a recess C into which a pin (not shown) can be inserted at a position overlapping with the through hole H when viewed from the side. The recess C shown in FIG. 3(d) is a groove portion having a bottom. On the other hand, although not specifically shown, the recess in the present disclosure may be a through portion.

[0024] Fig. 4(a) is a schematic plan view illustrating a block in the present disclosure, Fig. 4(b) is a cross-sectional view taken along line AA in Fig. 4(a), and Fig. 4(c) is a cross-sectional view taken along line BB in Fig. 4(a). As shown in Figs. 4(a) to (c), the block 11 has a slit portion S extending in a first direction D1. As shown in Fig. 4(b), the slit portion S extends in a thickness direction D T The length at L S As described above, the thickness of the insert 6 is T6. S is, for example, 1.0 times or more and 3.0 times or less, or may be 1.05 times or more and 2.0 times or less, or may be 1.1 times or more and 1.5 times or less, relative to T6. Sis not particularly limited, but is, for example, 0.05 mm or more and 1.5 mm or less. Also, as shown in Fig. 4(b), the block 11 may have a chamfered portion α at the end (the end on the insert side) of the slit portion S. The chamfered portion may be an R chamfer or a C chamfer.

[0025] The block in the present disclosure has an integral structure. An integral structure means that one slit portion is formed by a single member. For example, a block in which one slit portion is formed from two separable members does not fall under a block having an integral structure, but falls under a block having a divided structure. A block having an integral structure can reduce the number of components of the block, compared to a block having a divided structure, for example. In addition, in the case of a block having a divided structure, it is necessary to accurately position each through hole in the divided components, but a block having an integral structure has the advantage that the above positioning is not necessary.

[0026] The material of the block is not particularly limited, but examples thereof include resin, rubber, and metal. When the material of the block is resin or rubber, since resin or rubber is usually insulating, even if the block is worn, the generation of conductive foreign matter can be suppressed. On the other hand, when the material of the block is metal, the durability of the block can be increased. From the viewpoint of suppressing the generation of conductive foreign matter, it is preferable that the metal used for the block has high wear resistance. An example of a metal with high wear resistance is stainless steel.

[0027] 2. Second restriction step A second limiting step in the present disclosure is a step of inserting a pin into the block with the insert inserted from the thickness direction to limit the relative movement of the insert and the block in the first direction.

[0028] Figures 5(a), (c), and (e) are schematic plan views illustrating the second limiting step in the present disclosure, where Figure 5(b) is a cross-sectional view taken along line AA in Figure 5(a), Figure 5(d) is a cross-sectional view taken along line AA in Figure 5(c), and Figure 5(f) is a cross-sectional view taken along line AA in Figure 5(e). As shown in Figures 5(a) to (f), with the insert 6 inserted into the block 11, a pin P is inserted into a through-hole H in the insert 6 and a recess C in the block 11, thereby limiting the relative movement of the insert 6 and the block 11 in the first direction D1. The material of the pin is not particularly limited, and examples thereof include metal, resin, and rubber.

[0029] 3. Drawing process The pulling out step in the present disclosure is a step of pulling out the insert from the electrode member by moving the insert and the block away from the electrode stack in the first direction after the second restricting step.

[0030] As shown in Figures 5(e) and (f), the nest 6 and block 11 are moved away from the electrode stack (e.g., the electrode stack EL in Figure 1) in the first direction D1, thereby pulling out the nest 6 from the electrode member (e.g., the electrode member 10 in Figure 1).

[0031] In the pulling-out process, pressure may be applied to the insert and the block in the thickness direction when the insert and the block are moved away from the electrode stack. By applying pressure in the thickness direction, the frictional force between the insert and the block can be increased and added to the pulling load, thereby suppressing the shear force caused by the pin. The pressure applied in the thickness direction is, for example, 0.05 MPa or more and 0.1 MPa or less.

[0032] B. Energy Storage Module Manufacturing Method Fig. 6 is a flow diagram illustrating a method for manufacturing an electricity storage module according to the present disclosure. In Fig. 6, first, the electrode members described above are prepared (preparation step). Next, the insert is pulled out from the electrode member using the method described in "A. Method for pulling out insert" above, and a through hole is formed in the electrode member (through hole forming step). Next, an electrolyte is injected into the electrode stack through the through hole (injection step). Next, the through hole is sealed (sealing step).

[0033] According to the present disclosure, by using the above-described method for extracting the insert, deformation or breakage of the insert due to the pin can be suppressed when the insert is extracted from the electrode member.

[0034] 1. Preparation process The preparation step in the present disclosure is a step of preparing the above-mentioned electrode member. As shown in FIGS. 1(a) and 1(b), the electrode member 10 has a plurality of electrodes E arranged in a thickness direction D. T The electrode laminate EL is laminated on the sealing member 5, which is disposed so as to surround the electrode laminate EL, and the sealing member 5 is disposed in a first direction D perpendicular to the thickness direction. T and an insert 6 disposed so as to penetrate the seal member 5 in the electrode stack EL, with one end t1 located inside the electrode stack EL and the other end t2 located outside the seal member 5.

[0035] As shown in FIG. 1(b), the electrode member 10 has a plurality of electrodes E arranged in a thickness direction D. T 1(b), the electrode stack EL has, as electrodes E, a bipolar electrode BP, a positive end electrode CA, and a negative end electrode AN.

[0036] The bipolar electrode BP has a current collector 1, a positive electrode active material layer 2 arranged on one surface of the current collector 1, and a negative electrode active material 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 active material 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 active material layer 3 arranged on one surface of the current collector 1. The current collector 1 is, for example, a metal current collector. The positive electrode active material layer 2 contains at least a positive electrode active material, and may further contain a conductive material and a binder. The negative electrode active material layer 3 contains at least a negative electrode active material, and may further contain a conductive material and a binder.

[0037] As shown in FIG. 1(b), the electrode member 10 has a sealing member 5 arranged to surround the electrode laminate EL. The sealing member 5 contains, for example, a resin. The resin used for the sealing member 5 is, for example, a thermoplastic resin. Examples of the thermoplastic resin include polyolefins such as polyethylene and polypropylene. Also, as shown in FIG. 1(b), the electrode member 10 is oriented in a first direction D. T The electrode stack EL has a core 6 disposed so as to penetrate the seal member 5, with one end t1 located inside the electrode stack EL and the other end t2 located outside the seal member 5. The core 6 is made of, for example, metal.

[0038] As shown in FIG. 1(b), the electrode laminate EL is T The power generating unit may have a plurality of power generating units U (U1, U2, U3) stacked on top of each other. The power generating unit is usually a unit having a positive electrode active material layer, a separator, and a negative electrode active material layer. As described below, the power generating unit functions as a power storage module by being supplied with an electrolyte. As shown in FIG. 1(b), the power generating units U (U1, U2, U3) may be connected in series with each other. Although not particularly shown, the power generating units may be connected in parallel with each other.

[0039] The shape of the electrode laminate as viewed in the thickness direction (planar shape) is not particularly limited, but examples thereof include quadrangles such as squares and rectangles. For example, the planar shape of the electrode laminate EL shown in Figs. 1(a) and (b) is a quadrangle. The length of each side constituting the planar shape of the electrode laminate is not particularly limited, but may be, for example, 30 cm or more, 50 cm or more, or 100 cm or more. Meanwhile, the length of each of the above sides is, for example, 200 cm or less.

[0040] The method for preparing the electrode member is not particularly limited, but may be, for example, the method shown in Fig. 7. As shown in Fig. 7, each electrode E has a frame 51 surrounding the current collector 1. The frame 51 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 that constitutes the outer edge of the current collector 1. T Adjacent frame bodies 51 are thermally welded together to form a seal member (for example, seal member 5 in FIG. 1).

[0041] 7, the negative electrode active material layer 3 of the bipolar electrode BP1 and the positive electrode active material layer 2 of the bipolar electrode BP2 are opposed to each other with a separator 4 interposed therebetween. At this time, a nest 6 is disposed between the bipolar electrodes BP1 and BP2. In addition, another frame 51 (spacer 51a) is disposed between the frame 51 of the bipolar electrode BP1 and the frame 51 of the bipolar electrode BP2.

[0042] Next, the positive electrode active material layer 2 of the bipolar electrode BP1 and the negative electrode active material layer 3 of the negative electrode end electrode AN are opposed to each other via the separator 4. At this time, a nest 6 is placed between the bipolar electrode BP1 and the negative electrode end electrode AN. In addition, another frame 51 (spacer 51a) is placed between the frame 51 of the bipolar electrode BP1 and the frame 51 of the negative electrode end electrode AN.

[0043] Next, the negative electrode active material layer 3 of the bipolar electrode BP2 and the positive electrode active material layer 2 of the positive electrode end electrode CA are opposed to each other with the separator 4 interposed therebetween. At this time, a nest 6 is placed between the bipolar electrode BP2 and the positive electrode end electrode CA. In addition, another frame 51 (spacer 51) is placed between the frame 51 of the bipolar electrode BP2 and the frame 51 of the positive electrode end electrode CA. Thereafter, in the thickness direction D T Adjacent frame bodies 51 are thermally welded together to form a seal member (for example, seal member 5 in FIG. 1).

[0044] 2.Communication hole formation process The communication hole forming step in the present disclosure is a step of extracting the insert from the electrode member by using the insert extracting method described above, and forming a communication hole in the electrode member. The insert extracting method is the same as that described in "A. Insert Extracting Method" above.

[0045] In the present disclosure, during the communication hole forming step, injection molding may be performed to form a resin member that covers the side surface (surface extending in the thickness direction) of the seal member in the electrode member. For example, after the second restricting step and before the extracting step in the above-mentioned method for extracting a nest, the nest and the block are fixed to a mother mold, and an injection molding step of injection molding a resin is performed to form a resin member. The resin member is, for example, a liquid injection frame for fixing the position of the liquid injection nozzle during liquid injection. The above-mentioned method for extracting a nest may also include the above-mentioned injection molding step.

[0046] 3.Other processes The injection step in the present disclosure is a step of injecting an electrolyte solution into the electrode stack through the communication hole after the above-mentioned communication hole forming step. The method of injecting the electrolyte solution is not particularly limited, and a known method can be used.

[0047] The sealing step in the present disclosure is a step of sealing the communication hole after the above-mentioned liquid injection step. The method for sealing the communication hole is not particularly limited, but an example of the method is a method of sealing the communication hole by attaching a metal laminate.

[0048] 4. Energy storage module Specific examples of the power storage module 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 module 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 module 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 module 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.

[0049] 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]

[0050] 1...Current collector 2...Cathode active material layer 3...Negative electrode active material layer 4…Separator 5…Sealing material 6…Nesting 10...Electrode member 11…Block

Claims

1. A method for extracting a nest, comprising the steps of: The method is a method of pulling out the insert from an electrode member including: an electrode stack in which a plurality of electrodes are stacked in a thickness direction; a seal member arranged to surround the electrode stack; and the insert disposed to penetrate the seal member in a first direction perpendicular to the thickness direction, with one end located inside the electrode stack and the other end located outside the seal member, The method comprises: a first limiting step of using a block having a slit portion, bringing the slit portion of the block close to the insert positioned outside the seal member from the first direction, inserting the insert into the slit portion, and limiting relative movement of the insert and the block in the thickness direction; a second limiting step of inserting a pin into the block with the insert inserted therein from the thickness direction to limit relative movement of the insert and the block in the first direction; a pull-out step of pulling out the insert from the electrode member by moving the insert and the block away from the electrode stack in the first direction after the second restricting step; having the insert has a through hole into which the pin can be inserted, the block has a recess into which the pin can be inserted at a position overlapping with the through hole as viewed from the thickness direction when the insert is inserted, In the second limiting step, the pin is inserted into the through hole and the recess, thereby limiting the relative movement in the first direction; The block has a unitary structure.

2. 2. The insert removal method according to claim 1, wherein the block is made of a material selected from the group consisting of resin, rubber and metal.

3. The thickness of the insert is 0.5 mm or less, The method for extracting a insert core according to claim 1 , wherein a length of the slit portion in the thickness direction is 1.0 to 3.0 times the thickness of the insert core.

4. The insert extracting method according to claim 1 , wherein the electrode stack has bipolar electrodes as the electrodes.

5. A method for manufacturing an electric storage module, comprising the steps of: extracting the insert from the electrode member by using the insert extraction method according to any one of claims 1 to 4; and forming a through hole in the electrode member.

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