JP2020198190A - Manufacturing method of power storage module and power storage module - Google Patents

Abstract

To provide a manufacturing method of a power storage module capable of inhibiting deformation of an electrode, and to provide the power storage module.SOLUTION: This manufacturing method includes a first process of forming a first resin part 21A on the periphery of an electrode laminate 24 by injection molding of resin using a metal mould 28. The first process includes a first arrangement step of placing the electrode laminate 24 in the metal mould 28 so that the outer side face 24a faces a first cavity 35, and the first surface 24b faces a second cavity 36, and a first formation step of forming a first body part 22A by introducing resin from a common gate to the first and second cavities 35, 36 thereafter, and forming a first overhang part 23A.SELECTED DRAWING: Figure 5

Description

The present invention relates to a method for manufacturing a power storage module and a method for manufacturing a power storage module.

As a conventional power storage module, a bipolar battery including a bipolar electrode having a positive electrode formed on one surface of an electrode plate and a negative electrode formed on the other surface is known (see Patent Document 1). The bipolar battery includes a laminate formed by laminating a plurality of bipolar electrodes via a separator. On the side surface of the laminated body, a sealing body for sealing between the bipolar electrodes adjacent to each other in the stacking direction is provided, and the electrolytic solution is housed in the internal space formed between the bipolar electrodes.

Japanese Unexamined Patent Publication No. 2011-204386

As a method of providing the sealing body on the laminated body, for example, injection molding can be considered. In this case, the laminate is arranged in the mold so that the side surface of the laminate is exposed, and the resin is introduced into the mold. As a result, the sealing body is provided so as to cover the side surface of the laminated body. By the way, in order to improve the airtightness of the internal space, it is conceivable to provide an overhang portion extending from the side surface of the laminate to the front surface and the back surface of the sealed body.

That is, in order to improve the airtightness of the internal space, a sealing body including a main body portion that covers the side surface of the laminated body and an overhang portion extending from the main body portion to the front surface and the back surface of the laminated body is configured. That is one idea. On the other hand, when an attempt is made to form a sealed body including a main body portion and an overhang portion by injection molding, resin may enter between the bipolar electrodes constituting the laminated body, and the bipolar electrodes may be deformed so as to be rolled up.

Therefore, an object of the present invention is to provide a method for manufacturing a power storage module capable of suppressing deformation of electrodes and a power storage module.

The present inventor has obtained the following findings by proceeding with diligent studies in order to solve the above problems. That is, when the encapsulant is formed by injection molding, the resin enters between the electrodes and the electrodes are deformed because the resin introduced into the mold has a cavity (overhang) on the front surface (or back surface) side of the laminate. As a result of filling the cavity on the outer surface side of the laminate (cavity for the main body) before the cavity on the outer surface side of the laminate (cavity for the portion), the cavity on the front surface (or back surface) side of the laminate is not filled. This is because a resin flow is generated from the outer surface side of the laminated body to the front surface (or back surface) side. The present inventor has completed the present invention based on the above findings.

That is, the method for manufacturing a power storage module according to the present invention is a power storage module including an electrode laminate including a plurality of electrodes laminated along a first direction and a first resin portion for sealing the electrode laminate. It is a manufacturing method and includes a first step of forming a first resin portion on the outer peripheral portion of an electrode laminate by injection molding of a resin using a first mold, and the electrode laminate is laminated in the first direction. A first surface located at one end of the body, a second surface located at the other end of the electrode laminate in the first direction, and an outer surface extending along the first direction to connect the first surface and the second surface. The first resin portion includes a first main body portion that covers the outer surface of the electrode laminate, and a first over that extends from the first main body portion along the in-plane direction of the first surface of the electrode laminate. The first mold includes a hang portion, and when the electrode laminate is arranged inside, the first cavity faces the outer surface of the electrode laminate and extends along the first direction, and the first cavity A second cavity extending from the outer edge of the first surface of the connected electrode laminate along the in-plane direction of the first surface is formed between the electrode laminate and the electrode laminate. The first arrangement step of arranging the electrode laminate in the first mold so that the outer surface of the laminate faces the first cavity and the first surface of the electrode laminate faces the second cavity, and the first. After the first placement step, the resin is introduced into the first mold from the common gate to form the first main body portion from the resin filled in the first cavity, and the resin filled in the second cavity is used to form the first main body portion. 1 The first forming step of forming the overhang portion includes the first forming step of filling the first cavity with the resin, and the second forming step of filling the second cavity with the resin. In the first forming step, which includes a filling step, the first filling step is completed after the second filling step is completed.

In this manufacturing method, a first resin portion including a first main body portion that covers the outer surface of the electrode laminate and a first overhang portion that extends from the first main body portion to the first surface of the electrode laminate. Is formed by injection molding. More specifically, first, the electrode laminate so that the outer surface of the electrode laminate faces the first cavity of the mold and the first surface of the electrode laminate faces the second cavity of the mold. Is placed in the first mold. Then, by introducing the resin into the mold from the common gate, the first main body portion is formed by the resin filled in the first cavity, and the first overhang portion is formed by the resin filled in the second cavity. To do. As a result, the first resin portion is formed. In particular, in this manufacturing method, after the second filling step of filling the resin in the second cavity on the first surface side of the electrode laminate is completed, the resin is filled in the first cavity on the outer surface side of the electrode laminate. The first filling step of filling is completed. Therefore, the resin flow from the outer surface side to the first surface side is unlikely to occur when the second cavity is not filled. Therefore, it is possible to prevent the resin from entering between the electrodes and deforming the electrodes.

Here, as a result of further studies based on the above findings, the present inventor has obtained the following findings. That is, the thickness of the first cavity for the first body portion (dimensions in the second direction intersecting the first direction) is the thickness of the second cavity for the first overhang portion (in the first direction). If it is thicker than the above size), the resin preferentially flows into the first cavity, and as a result, the first cavity is likely to be filled first. By setting the thickness of the first cavity to be equal to or less than the thickness of the second cavity, it is possible to prevent the resin from preferentially flowing into the first cavity, and it becomes easier to fill the second cavity first.

Therefore, in the method for manufacturing the power storage module according to the present invention, in the first arrangement step, the thickness of the first cavity along the second direction orthogonal to the first direction is the thickness of the second cavity along the first direction. The electrode laminate may be arranged in the first mold so as to be less than or equal to the thickness. By controlling the thickness of the cavity in this way, it is possible to surely complete the filling of the resin into the first cavity after completing the filling of the resin into the second cavity and suppress the deformation of the electrode.

By the way, if the relative thickness between the cavities is controlled as described above, the thickness of the first main body portion in the first resin portion is limited to the thickness of the first overhang portion or less.

Therefore, in the method for manufacturing a power storage module according to the present invention, a resin using a second mold is used on an outer peripheral portion of a battery structure including an electrode laminate and a first resin portion formed in the first step. A second step of forming the second resin portion by injection molding is further provided, and the second resin portion includes the second main body portion that covers the first main body portion and the in-plane of the second surface of the electrode laminate from the second main body portion. The second mold includes a second overhang portion extending along the direction, and the second mold faces the first main body portion and extends along the first direction when the battery structure is arranged inside. The three cavities and the fourth cavity connected to the third cavity and extending from the outer edge of the second surface of the electrode laminate along the in-plane direction of the second surface are formed between the battery structure. In the second step, the battery structure is arranged in the second mold so that the first main body portion faces the third cavity and the second surface of the electrode laminate faces the fourth cavity. After the second placement step and the second placement step, the resin is introduced into the second mold to form the second main body portion from the resin filled in the third cavity and to fill the fourth cavity. In the second arrangement step, the thickness of the third cavity along the second direction is the fourth cavity along the first direction, including the second forming step of forming the second overhang portion with the resin. The battery structure may be arranged in the second mold so as to be thicker than the thickness of the above. According to this, the second main body portion that can be formed relatively thick is provided so as to cover the first main body portion that tends to be relatively thin, and the airtightness can be improved.

In the method for manufacturing the power storage module according to the present invention, in the first arrangement step, the cross-sectional area of the first cavity in the cross section orthogonal to the first direction is the cross-sectional area of the second cavity in the cross section along the first direction. The electrode laminate may be arranged in the first mold so as to be smaller than the above. Alternatively, in the first arrangement step, the electrode laminate may be arranged in the first mold so that the volume of the first cavity is larger than the volume of the second cavity. In this way, when the filling of the resin into the second cavity is completed and then the filling of the resin into the first cavity is completed to suppress the deformation of the electrode, at least one of the thickness, the cross-sectional area, and the volume of the cavity is used. Can be controlled.

The power storage module according to the present invention includes an electrode laminate including a plurality of electrodes laminated along the first direction, and a first resin portion and a second resin portion for sealing the electrode laminate. The electrode laminate has a first surface located at one end of the electrode laminate in the first direction, a second surface located at the other end of the electrode laminate in the first direction, and a first surface extending along the first direction. The first resin portion includes a first main body portion that covers the outer surface of the electrode laminate, and a surface of the first surface of the electrode laminate from the first main body portion, including an outer surface that connects the surface and the second surface. The second resin portion includes a first overhang portion extending inward, a second main body portion covering the first main body portion, and a surface of the second surface of the electrode laminate from the second main body portion. The thickness of the first main body portion along the second direction orthogonal to the first direction, including the second overhang portion extending along the inward direction, is the thickness of the first main body portion along the first direction. It is equal to or less than the thickness of the overhang portion, and the thickness of the second main body portion along the second direction is thicker than the thickness of the second overhang portion along the first direction.

This power storage module can be manufactured, for example, as follows. That is, first, a first resin portion including a first main body portion that covers the outer surface of the electrode laminate and a first overhang portion that extends from the first main body portion over the first surface of the electrode laminate is injected. It is formed by molding. More specifically, first, the electrode laminate so that the outer surface of the electrode laminate faces the first cavity of the mold and the first surface of the electrode laminate faces the second cavity of the mold. Is placed in the first mold. Then, by introducing the resin into the mold from the common gate, the first main body portion is formed by the resin filled in the first cavity, and the first overhang portion is formed by the resin filled in the second cavity. .. As a result, the first resin portion is formed. In particular, when forming the first resin portion, after the filling of the resin into the second cavity on the first surface side of the electrode laminate is completed, the resin is filled into the first cavity on the outer surface side of the electrode laminate. Complete. As a result, the resin flow from the outer surface side to the first surface side is less likely to occur when the second cavity is not filled. Therefore, it is possible to prevent the resin from entering between the electrodes and deforming the electrodes. Further, according to this power storage module, airtightness is improved by providing a second main body portion thicker than the second overhang so as to cover the first main body portion having a thickness equal to or less than that of the first overhang. Ru.

According to the present invention, it is possible to provide a method for manufacturing a power storage module capable of suppressing deformation of electrodes and a power storage module.

It is schematic cross-sectional view which shows the power storage device which includes the power storage module which concerns on embodiment. It is the schematic sectional drawing which shows the internal structure of the power storage module shown in FIG. It is a schematic cross-sectional view of the power storage module shown in FIG. 2, and is a figure for demonstrating the details of the secondary resin seal. It is a flowchart which shows the main process of the manufacturing method of the power storage module shown in FIGS. It is sectional drawing for demonstrating the manufacturing method shown in FIG. It is sectional drawing for demonstrating the manufacturing method shown in FIG. It is sectional drawing for demonstrating the manufacturing method shown in FIG. It is a figure which shows the 1st simulation example. It is a figure which shows the 1st simulation example. It is a figure which shows the 2nd simulation example. It is a figure which shows the 2nd simulation example. It is a figure which shows the 3rd simulation example. It is a figure which shows the 3rd simulation example.

Subsequently, the power storage module according to the present embodiment and the method for manufacturing the power storage module will be described with reference to the drawings. In the description of each figure, the same or corresponding elements are designated by the same reference numerals, and duplicate description will be omitted. Further, the following figure may show a Cartesian coordinate system defined by the X-axis, the Y-axis, and the Z-axis.

FIG. 1 is a schematic cross-sectional view showing a power storage device including the power storage module according to the embodiment. The power storage device 1 shown in FIG. 1 can be used as a battery for a vehicle such as a forklift, a hybrid vehicle, or an electric vehicle. The power storage device 1 includes a plurality of (three in this case) power storage modules 2. The power storage module 2 is, for example, a secondary battery such as a nickel hydrogen secondary battery or a lithium ion secondary battery, or an electric double layer capacitor. In the following description, a nickel hydrogen secondary battery will be illustrated.

The plurality of power storage modules 2 are laminated via a metal conductive plate 3. The outermost layer (stack outermost layer) in the stacking direction (for example, the Z-axis direction) of the laminated body of the power storage module 2 and the conductive plate 3 is the power storage module 2 as an example. The power storage module 2 and the conductive plate 3 have, for example, a rectangular shape (rectangular shape in a plan view) when viewed from the stacking direction. The conductive plate 3 is electrically connected to the adjacent power storage modules 2. As a result, the plurality of power storage modules 2 are connected in series in the stacking direction. The power storage module 2 will be described in detail later.

A positive electrode terminal 4 is connected to a power storage module 2 located at one end (lower end in this case) in the stacking direction. The negative electrode terminal 5 is connected to the power storage module 2 located at the other end (here, the upper end) in the stacking direction. The positive electrode terminal 4 and the negative electrode terminal 5 extend in a direction (for example, the X-axis direction) intersecting (orthogonal) in the stacking direction. By providing such a positive electrode terminal 4 and a negative electrode terminal 5, charging / discharging of the power storage device 1 can be performed. In the power storage device 1, the outermost layer of the stack may be the conductive plate 3. In this case, the positive electrode terminal 4 and the negative electrode terminal 5 can be provided on the conductive plate 3 on the outermost layer of the stack.

The conductive plate 3 can also function as a heat radiating plate for releasing the heat generated in the power storage module 2. The conductive plate 3 is provided with a plurality of voids 3a extending in a direction (for example, the Y-axis direction) that intersects (orthogonally) the stacking direction of the power storage module 2 and the extending direction of the positive electrode terminal 4 and the negative electrode terminal 5. There is. When a refrigerant such as air passes through these voids 3a, the heat from the power storage module 2 can be efficiently released to the outside.

Further, the power storage device 1 includes a restraint unit 6 that restrains the power storage module 2 and the conductive plate 3 in the stacking direction. The restraint unit 6 has a pair of restraint plates 7 that sandwich the power storage module 2 and the conductive plate 3 in the stacking direction, and a plurality of sets of bolts 8 and nuts 9 that fasten the restraint plates 7 to each other.

The restraint plate 7 is made of a metal such as iron. An insulating film 10 such as a resin film is arranged between each restraint plate 7 and the power storage module 2. The restraint plate 7 and the insulating film 10 have, for example, a rectangular shape in a plan view. With the shaft portion 8a of the bolt 8 inserted through the insertion holes 7a provided in each restraint plate 7, the nut 9 is screwed into the tip portion of the shaft portion 8a, whereby the power storage module 2, the conductive plate 3, and the insulating film are screwed. A restraining load in the stacking direction is applied to 10. When the outermost layer of the stack is the conductive plate 3, the insulating film 10 is interposed between each of the restraint plates 7 and the conductive plate 3.

Next, the configuration of the power storage module 2 will be described in detail. FIG. 2 is a schematic cross-sectional view showing the internal configuration of the power storage module shown in FIG. As shown in FIG. 2, the power storage module 2 includes an electrode laminate 13 and a resin sealant 14 for sealing the electrode laminate 13. The electrode laminate 13 has a plurality of electrodes (a plurality of bipolar electrodes 11, a single negative electrode terminal electrode 19, and a single negative electrode terminal electrode 19) laminated along a stacking direction (first direction, in this case, the Z-axis direction) via a separator 12. , A single positive electrode termination electrode 18).

The bipolar electrode 11 includes an electrode plate 15, a positive electrode 16 provided on the first surface 15a of the electrode plate 15, and a negative electrode 17 provided on the second surface 15b opposite to the first surface 15a of the electrode plate 15. The positive electrode 16 is a positive electrode active material layer formed by coating the electrode plate 15 with the positive electrode active material. The negative electrode 17 is a negative electrode active material layer formed by applying the negative electrode active material to the electrode plate 15. In the electrode laminate 13, the positive electrode 16 of one bipolar electrode 11 faces the negative electrode 17 of another electrode (bipolar electrode 11 or negative electrode terminal electrode 19) adjacent to each other in the stacking direction with the separator 12 interposed therebetween. In the electrode laminate 13, the negative electrode 17 of one bipolar electrode 11 faces the positive electrode 16 of yet another electrode (bipolar electrode 11 or positive electrode terminal electrode 18) adjacent to each other in the stacking direction with the separator 12 interposed therebetween.

The negative electrode terminal electrode 19 includes an electrode plate 15 and a negative electrode 17 provided on the second surface 15b of the electrode plate 15. The negative electrode terminal electrode 19 is arranged at one end in the stacking direction so that the second surface 15b faces the inside of the electrode stack 13 (center side in the stacking direction). The negative electrode 17 of the negative electrode terminal electrode 19 faces the positive electrode 16 of the bipolar electrode 11 at one end in the stacking direction via the separator 12. The positive electrode terminal electrode 18 includes an electrode plate 15 and a positive electrode 16 provided on the first surface 15a of the electrode plate 15. The positive electrode terminal electrode 18 is arranged at the other end in the stacking direction so that the first surface 15a faces the inside of the electrode laminate 13. The positive electrode 16 of the positive electrode terminal electrode 18 faces the negative electrode 17 of the bipolar electrode 11 at the other end in the stacking direction via the separator 12.

In the power storage module 2 excluding the outermost layer of the stack, the conductive plate 3 is in contact with the first surface 15a of the electrode plate 15 of the negative electrode terminal electrode 19. Further, in the power storage module 2 excluding the outermost layer of the stack, another conductive plate 3 is in contact with the second surface 15b of the electrode plate 15 of the positive electrode terminal electrode 18. In this case, the restraining load is applied to the electrode laminate 13 from the negative electrode terminal electrode 19 and the positive electrode terminal electrode 18 via the conductive plate 3. That is, the conductive plate 3 is also a restraining member that applies a restraining load to the electrode laminated body 13 along the stacking direction.

The electrode plate 15 is made of a metal such as nickel or a nickel-plated steel plate. As an example, the electrode plate 15 is a rectangular metal leaf made of nickel. The peripheral edge of the electrode plate 15 (the bipolar electrode 11, the negative electrode terminal electrode 19, and the edge of the positive electrode terminal 18) has a rectangular frame shape, and has an uncoated area where the positive electrode active material and the negative electrode active material are not coated. It has become. Examples of the positive electrode active material constituting the positive electrode 16 include nickel hydroxide. Examples of the negative electrode active material constituting the negative electrode 17 include a hydrogen storage alloy. In the present embodiment, the formation region of the negative electrode 17 on the second surface 15b of the electrode plate 15 is larger than the formation region of the positive electrode 16 on the first surface 15a of the electrode plate 15.

The separator 12 is formed in a sheet shape, for example. Examples of the separator 12 include a porous film made of a polyolefin resin such as polyethylene (PE) and polypropylene (PP), a woven fabric made of polypropylene, methyl cellulose and the like, or a non-woven fabric. The separator 12 may be reinforced with a vinylidene fluoride resin compound.

The encapsulant 14 is arranged so as to surround the electrode laminate 13, and a plurality of 1s each holding the peripheral edge portion 15c of the electrode plate 15 of the electrodes (bipolar electrode 11, negative electrode termination electrode 19, and positive electrode termination electrode 18). It has a secondary resin seal 20 and a secondary resin seal 21 arranged so as to surround the primary resin seal 20. The primary resin seal 20 is arranged for each electrode plate 15 along the stacking direction. The primary resin seal 20 has a frame shape. The primary resin seal 20 is bonded (for example, welded) to the peripheral edge portion 15c of the electrode plate 15. The primary resin seal 20 and the secondary resin seal 21 are, for example, insulating resins and may be composed of polypropylene (PP), polyphenylene sulfide (PPS), modified polyphenylene ether (modified PPE), or the like.

An internal space V defined by the electrode plates 15 and the primary resin seal 20 is provided between the electrode plates 15 adjacent to each other in the stacking direction. An alkaline electrolytic solution is injected into the internal space V. As the alkaline electrolytic solution, an alkaline solution containing, for example, an aqueous potassium hydroxide solution is used. The primary resin seal 20 is for sealing the internal space V. One cell in the power storage module 2 is composed of two electrode plates 15, a positive electrode 16, a negative electrode 17, a separator 12, and a primary resin seal 20, and has an internal space V.

That is, here, the electrode laminate 13 and the primary resin seal 20 further constitute the electrode laminate 24. The electrode laminate 24 has an electrode unit 25 formed by bonding (for example, welding) a primary resin seal 20 to the peripheral edge of the bipolar electrode 11, and a primary resin seal 20 bonded (for example) to the peripheral edge of the positive electrode terminal electrode 18. The electrode unit 26 formed by welding) and the electrode unit 27 formed by joining (for example, welding) a primary resin seal 20 to the negative electrode terminal electrode 19 are laminated via a separator 12. ing.

The electrode laminate 24 is laminated with a first surface 24b that intersects (orthogonally) in the lamination direction (first direction) and a second surface 24c that intersects (orthogonally) in the lamination direction and is opposite to the first surface 24b. Includes an outer surface 24a that extends along a direction (first direction) and connects the first surface 24b and the second surface 24c. The first surface 24b is located at one end of the electrode laminate 24 in the lamination direction. The second surface 24c is located at the other end of the electrode laminate 24 in the lamination direction. The first surface 24b includes a first surface 15a of the electrode plate 15 of the negative electrode terminal electrode 19 and a surface facing the outside of the primary resin seal 20 joined to the first surface 15a in the stacking direction. The second surface 24c includes a second surface 15b of the electrode plate 15 of the positive electrode terminal electrode 18 and a surface facing the outside of the primary resin seal 20 joined to the second surface 15b in the stacking direction. The outer side surface 24a includes a set of outer surfaces along the stacking direction of the primary resin seal 20. The peripheral portion of the first surface 24b and the second surface 24c and the outer peripheral surface 24a form an outer peripheral portion of the electrode laminate 24. The secondary resin seal 21 is provided on the outer peripheral portion of the electrode laminate 24.

The secondary resin seal 21 has a square tubular main body 22 and a pair of upper and lower rectangular rings protruding from both ends (one end and the other end) of the main body 22 to the inside of the primary resin seal 20 in the stacking direction. It has an overhang portion 23 and. The overhang portion 23 extends from the main body portion 22 so as to overlap the electrode laminate 24 (primary resin seal 20). The overhang portion 23 sandwiches a plurality of primary resin seals 20 in the stacking direction. By providing the overhang portion 23 on the secondary resin seal 21, it is possible to suppress the swelling of the power storage module 2 due to repeated charging and discharging of the power storage module 2. The secondary resin seal 21 is formed by injection molding (described later). The secondary resin seal 21 is joined to the primary resin seal 20. The secondary resin seal 21 is for sealing the internal space V together with the primary resin seal 20.

FIG. 3 is a schematic cross-sectional view of the power storage module shown in FIG. 2 and is a diagram for explaining the details of the secondary resin seal. As shown in FIG. 3, the secondary resin seal 21 has a first resin portion 21A and a second resin portion 21B. As will be described later, the first resin portion 21A and the second resin portion 21B are each formed by injection molding. The first resin portion 21A is formed on the outer peripheral portion of the electrode laminate 24. The second resin portion 21B is formed on the outside of the first resin portion 21A. The first resin portion 21A and the second resin portion 21B are each formed in a frame shape, and face the outside of the electrode laminate 24 in the directions (Y-axis direction and Z-axis direction) intersecting (orthogonal) in the lamination direction. They are arranged in order. The first resin portion 21A and the second resin portion 21B are joined to each other.

The first resin portion 21A includes a first main body portion 22A that covers the outer surface 24a of the electrode laminate 24, and a first overhang portion 23A that extends from the first main body portion 22A over the first surface 24b of the electrode laminate 24. And, including. The first overhang portion 23A extends along the in-plane direction of the first surface 24b. The first main body portion 22A constitutes an inner portion of the main body portion 22 of the secondary resin seal 21. The first overhang portion 23A is one of a pair of overhang portions 23 of the secondary resin seal 21. The first resin portion 21A is formed in an L-shaped cross section by the first main body portion 22A and the first overhang portion 23A.

The second resin portion 21B includes a second main body portion 22B that covers the first main body portion 22A, and a second overhang portion 23B that extends from the second main body portion 22B over the second surface 24c of the electrode laminate 24. Including. The second overhang portion 23B extends along the in-plane direction of the second surface 24c. The second main body portion 22B constitutes an outer portion of the main body portion 22 of the secondary resin seal 21. The second overhang portion 23B is the other of the pair of overhang portions 23 of the secondary resin seal 21. The second resin portion 21B is formed by the second main body portion 22B and the second overhang portion 23B in an L-shaped cross section opposite to that of the first resin portion 21A.

The thickness T22A of the first main body portion 22A along the direction intersecting (orthogonal) in the stacking direction (here, the Y-axis direction or the X-axis direction, hereinafter referred to as “the second direction”) is the stacking direction (here, Z). It is the axial direction, and is not more than the thickness T23A of the first overhang portion 23A along the "first direction"). The thickness T22A may be the same as the thickness T23A or may be thinner than the thickness T23A. As an example, the cross-sectional area of the first main body portion 22A in the cross section intersecting (orthogonal) in the first direction is the cross section of the first overhang portion 23A along the first direction (crossing (orthogonal) in the second direction). It is less than the cross-sectional area. For example, the cross-sectional area of the first main body portion 22A in the cross section intersecting (orthogonal) in the first direction is the cross section of the first overhang portion 23A along the first direction (crossing (orthogonal) in the second direction). Smaller than the area.

The length L22A of the first main body portion 22A along the first direction is longer than the length L23A of the first overhang portion 23A along the second direction. Here, the volume of the first main body portion 22A is made larger than the volume of the first overhang portion 23A. The length L23A is the length of the portion of the first resin portion 21A that overlaps with the electrode laminate 24 when viewed from the first direction. Further, the length L22A is the total length of the portion of the first resin portion 21A that overlaps the electrode laminate 24 and the portion of the first resin portion 21A that protrudes from the first surface 24b when viewed from the second direction. ..

The thickness T22B of the second main body portion 22B along the second direction is thicker than the thickness T23B of the second overhang portion 23B along the first direction. The thickness T23A of the first overhang portion 23A and the thickness T23B of the second overhang portion 23B are, for example, the same. In this case, the thickness T22B of the second main body 22B is thicker than the thickness T22A of the first main body 22A. The thickness T22A of the first main body 22A and the thickness T22B of the second main body 22B can be set complementarily. That is, the thickness T22A and the thickness T22B can be set so that the total of them is the thickness required for the main body portion 22. In this case, the second main body 22B is thickened by the amount that the first main body 22A is thinned.

Subsequently, a method of manufacturing the power storage module 2 will be described. FIG. 4 is a flowchart showing a main process of the method of manufacturing the power storage module shown in FIGS. 2 and 3. In this manufacturing method, first, a plurality of bipolar electrodes 11 are manufactured (step S101). In step S101, in addition to the bipolar electrode 11, the positive electrode terminal electrode 18 and the negative electrode terminal electrode 19 are also manufactured. On the other hand, a plurality of resin members for the primary resin seal 20 are produced (step S102). The order of these steps does not matter.

Then, a plurality of electrode units 25 are manufactured by welding the primary resin seal 20 to the peripheral edge of the electrode plate 15 of the bipolar electrode 11 (step S103). More specifically, in this step S103, a plurality of (for example, four) resin members produced in step S102 are arranged and welded on the peripheral edge of the bipolar electrode 11 so as to form a frame shape. As a result, the resin members and the resin member and the bipolar electrode 11 are welded to each other to produce a primary resin seal 20 provided on the peripheral edge of the bipolar electrode 11, and the electrode unit 25 including the primary resin seal 20 is produced. Is produced.

As described above, here, welding the primary resin seal 20 to the welded member means that the primary resin seal 20 is welded to the welded member as a result of welding of the member that is the source of the primary resin seal 20. Including the case where is formed. However, when the primary resin seal 20 is welded to the member to be welded, a frame-shaped primary resin seal 20 may be formed in advance and directly welded to the member to be welded.

In step S103, the electrode units 26 and 27 are also manufactured in addition to the electrode unit 25. Next, the electrode laminated body 24 is manufactured by laminating the plurality of electrode units 25 and the electrode units 26 and 27 via the separator 12 (step S104). Steps S101 to S104 are steps for producing the electrode laminate 13 and the electrode laminate 24 having the plurality of primary resin seals 20.

In the subsequent steps, a secondary resin seal is produced by injection molding of the resin using a mold (step S105: first step, second step). This step S105 will be described in more detail. FIG. 5A is a partial cross-sectional view showing a state in which the electrode laminate 24 is arranged inside the mold (first mold) 28. FIG. 5B is a partially enlarged view of FIG. 5A. As shown in FIG. 5, the mold 28 has a lower mold 30 and an upper mold 31. The lower mold 30 is provided with a storage recess 32 in which the electrode laminate 24 is housed. The accommodating recess 32 has a rectangular shape with a cross section cut perpendicular to the vertical direction H of the mold 28. In a state where the electrode laminate 24 is accommodated in the accommodating recess 32, a cavity 33 filled with resin is formed around the outer peripheral portion of the electrode laminate 24 between the inner surfaces 32a and 31a of the accommodating recess 32. Has been done.

More specifically, when the electrode laminate 24 is arranged inside (accommodation recess 32), the mold 28 faces the outer surface 24a of the electrode laminate 24 and extends along the first direction. The cavity 35 and the second cavity 36 facing the outer edge of the first surface 24b of the electrode laminate 24 and extending along the second direction are configured to be formed between the electrode laminate 24. .. The second cavity 36 is connected to the first cavity 35 and extends along the outer edge portion of the first surface 24b of the electrode laminate 24 (extending from the outer edge portion along the in-plane direction of the first surface 24b). .. Further, the mold 28 is provided with a resin introduction portion (gate) P1 for introducing the resin into the cavity 33. The resin introduction portion P1 is provided on the upper mold 31 as an example. The resin introduction portion P1 is provided at a position overlapping the connection portion with the second cavity 36 in the first cavity 35 when viewed from the first direction. The resin derived from the resin introduction unit P1 is simultaneously introduced into both the first cavity 35 and the second cavity 36. That is, the resin introduction portion P1 is a common gate commonly used for introducing the resin into the first cavity 35 and the second cavity 36.

The first cavity 35 is for forming the first main body portion 22A of the first resin portion 21A. The second cavity 36 is for forming the first overhang portion 23A of the first resin portion 21A. Therefore, the shapes and dimensions of the first cavity 35 and the second cavity 36 correspond to the shapes and dimensions of the first main body portion 22A and the first overhang portion 23A.

That is, the thickness T35 of the first cavity 35 along the second direction is equal to or less than the thickness T36 of the second cavity 36 along the first direction. The thickness T35 may be the same as the thickness T36 or may be thinner than the thickness T36. The thickness T35 is, for example, about 150% of the thickness T36. As an example, the cross-sectional area of the first cavity 35 in the cross section intersecting (orthogonal) in the first direction is equal to or less than the cross-sectional area of the second cavity 36 along the first direction (crossing (orthogonal) in the second direction). Is. For example, the cross-sectional area of the first cavity 35 in the cross section intersecting (orthogonal) in the first direction is larger than the cross-sectional area of the second cavity 36 in the cross section along the first direction (crossing (orthogonal) in the second direction). small. The length L35 of the first cavity 35 along the first direction is longer than the length L36 of the second cavity 36 along the second direction. Here, the volume of the first cavity 35 is made larger than the volume of the second cavity 36. The length L36 is the length of the portion of the cavity 33 that overlaps the electrode laminate 24 when viewed from the first direction. Further, the length L35 is the length of the portion of the cavity 33 that overlaps the electrode laminate 24 and the portion of the cavity 33 that protrudes from the first surface 24b (that is, the thickness of the second cavity 36) when viewed from the second direction. It is the total of T36).

In step S105, first, the first resin portion 21A is formed on the outer peripheral portion of the electrode laminate 24 by injection molding of the resin using the mold 28 as described above (first step). That is, here, first, the electrode laminate 24a is such that the outer surface 24a of the electrode laminate 24 faces the first cavity 35, and the first surface 24b of the electrode laminate 24 faces the second cavity 36. Is placed in the mold 28 (first placement step). After that, as shown in FIG. 6, the resin is introduced into the mold 28 from the resin introduction portion P1 which is a common gate (that is, simultaneously in the first cavity 35 and the second cavity 36), thereby causing the first cavity 35. The first main body portion 22A is formed of the resin filled in, and the first overhang portion 23A is formed of the resin filled in the second cavity 36 (first forming step).

In particular, here, the filling of the resin into the second cavity 36 is completed before the filling of the resin into the first cavity 35. That is, the first forming step includes a first filling step of filling the first cavity 35 with the resin and a second filling step of filling the second cavity 36 with the resin, and the second filling step includes. After completion, the first filling step is completed. This is realized by the relationship between the dimensions of the first cavity 35 and the second cavity 36. That is, as an example, in the first forming step, the resin is introduced into the mold 28 in a state where the thickness T35 of the first cavity 35 is equal to or less than the thickness T36 of the second cavity 36. 2 After the filling step is completed, the first filling step is completed. In other words, in the first arrangement step, the thickness T35 of the first cavity 35 along the second direction orthogonal to the first direction is equal to or less than the thickness T36 of the second cavity 36 along the first direction. As described above, the electrode laminate 24 is arranged in the mold 28.

In addition to the thickness of such a cavity (or in addition to the thickness), by controlling other parameters such as the cross-sectional area, volume, and length of the cavity, the first cavity 35 is more than filled with resin. The filling of the resin into the second cavity 36 may be completed first. That is, in the first forming step, the cross-sectional area of the first cavity 35 in the cross section intersecting (orthogonal) in the first direction is smaller than the cross-sectional area of the second cavity 36 in the cross section along the first direction. In, the first filling step may be completed after the second filling step is completed by introducing the resin into the mold 28. In other words, in the first arrangement step, the cross-sectional area of the first cavity 35 in the cross section intersecting (orthogonal) in the first direction is smaller than the cross-sectional area of the second cavity 36 in the cross section along the first direction. As described above, the electrode laminate 24 may be arranged in the mold 28. Further, in the first forming step, the second filling step is completed by introducing the resin into the mold 28 in a state where the volume of the first cavity 35 is larger than the volume of the second cavity 36. The first filling step may be completed later. In other words, in the first arrangement step, the electrode laminate 24 may be arranged in the mold 28 so that the volume of the first cavity 35 is larger than the volume of the second cavity 36. As described above, here, at least one of the thickness, the cross-sectional area, and the volume (any combination thereof) can be controlled so that the first filling step is completed after the second filling step is completed. .. As described above, the first resin portion 21A is produced, and the battery structure 37 including the electrode laminate 24 and the first resin portion 21A is produced.

In step S105, subsequently, as shown in FIG. 7, a second resin portion 21B is formed on the outer peripheral portion of the battery structure 37 by injection molding of a resin using a mold (second mold) 29. (Second step). As shown in FIG. 7, the mold 29 has an upper mold 38 and a lower mold 39. In a state where the battery structure 37 is housed in the mold 29, a cavity 40 is filled with resin between the outer peripheral portion of the battery structure 37 and the inner surface 39a of the mold 29 (lower mold 39). Is formed. More specifically, the mold 29 is formed on the outer surface 37a of the battery structure 37, which is the outer surface of the first main body 22A extending along the first direction when the battery structure 37 is arranged inside. A third cavity 41 extending along the first direction and a fourth cavity extending along the second direction from the third cavity 41 while facing the second surface 24c of the battery structure 37 (electrode laminated body 24). 42 and 42 are configured to be formed between the battery structure 37 and the battery structure 37. The fourth cavity 42 is connected to the third cavity 41 and extends along the outer edge portion of the second surface 24c of the electrode laminate 24 (extending from the outer edge portion along the in-plane direction of the second surface 24c).

The third cavity 41 is for forming the second main body portion 22B of the second resin portion 21B. The fourth cavity 42 is for forming the second overhang portion 23B of the second resin portion 21B. Therefore, the shapes and dimensions of the third cavity 41 and the fourth cavity 42 correspond to the shapes and dimensions of the second main body portion 22B and the second overhang portion 23B. That is, the thickness T41 of the third cavity 41 along the second direction is thicker than the thickness T42 of the fourth cavity along the first direction.

Here, the battery structure 37 is arranged in the mold 29 as described above. That is, the battery structure 37 is arranged in the mold 29 so that the first main body 22A faces the third cavity 41 and the second surface 24c faces the fourth cavity 42 (second arrangement step). ). After that, by introducing the resin into the mold 29 via the resin introducing portion P2, the second main body portion 22B is formed by the resin filled in the third cavity 41, and the resin filled in the fourth cavity 42 is formed. The second overhang portion 23B is formed by the above (second forming step). In particular, as described above, here, the third cavity is in a state where the thickness T41 of the third cavity 41 along the second direction is thicker than the thickness T42 of the fourth cavity 42 along the first direction. The resin is introduced into the 41 and the fourth cavity 42 (that is, the mold 29). In other words, in the second arrangement step, the battery structure is such that the thickness T41 of the third cavity 41 along the second direction is thicker than the thickness T42 of the fourth cavity 42 along the first direction. The body 37 is placed in the mold 29. As a result, the second resin portion 21B is produced.

After that, the power storage module 2 is subjected to a step of injecting an electrolytic solution into the internal space V of the electrode laminate 24 (electrode laminate 13) via the liquid injection port, and then sealing the liquid injection port. Manufactured.

As described above, in the manufacturing method according to the present embodiment, the first main body portion 22A covering the outer surface 24a of the electrode laminated body 24 and the first main body portion 22A over the first surface 24b of the electrode laminated body 24. The extending first overhang portion 23A and the first resin portion 21A including the extending first overhang portion 23A are formed by injection molding. More specifically, first, the outer surface 24a of the electrode laminate 24 faces the first cavity 35 of the mold 28, and the first surface 24b of the electrode laminate 24 is the second cavity 36 of the mold 28. The electrode laminate 24 is arranged in the mold 28 so as to face the above. Then, by introducing the resin into the mold 28 from the common gate, the first main body portion 22A is formed by the resin filled in the first cavity 35, and the first overhang is formed by the resin filled in the second cavity 36. The hang portion 23A is formed. As a result, the first resin portion 21A is formed.

In particular, in the manufacturing method according to the present embodiment, after the second filling step of filling the second cavity 36 on the first surface 24b side of the electrode laminate 24 with the resin is completed, the outer surface of the electrode laminate 24 The first filling step of filling the first cavity 35 on the 24a side with the resin is completed. Therefore, in a state where the second cavity 36 is not filled, a resin flow from the outer surface 24a side to the first surface 24b side is unlikely to occur. Therefore, it is possible to prevent the resin from entering between the electrodes and deforming the electrodes.

Further, in the manufacturing method according to the present embodiment, in the first arrangement step, the thickness of the first cavity 35 along the second direction intersecting (orthogonal) with the first direction is the second thickness along the first direction. The electrode laminate 24 is arranged in the mold 28 so as to be equal to or less than the thickness of the cavity 36. As a result, the first filling step is completed after the second filling step is completed. By controlling the thickness of the cavity in this way, it is possible to surely complete the first filling step after the second filling step is completed and suppress the deformation of the electrode.

Further, in the manufacturing method according to the present embodiment, the second resin portion 21B is formed on the outer peripheral portion of the battery structure 37 including the electrode laminate 24 and the first resin portion 21A by injection molding of a resin using a mold 29. A second step of forming is further provided. The second resin portion 21B includes a second main body portion 22B that covers the first main body portion 22A, and a second overhang portion 23B that extends from the second main body portion 22B over the second surface 24c. When the battery structure 37 is arranged inside the mold 29, the third cavity 41 extending along the first direction and the fourth cavity connecting to the third cavity 41 and extending along the outer edge of the second surface 24c. The cavity 42 and the cavity 42 are configured to be formed between the cavity 42 and the battery structure 37.

In the second step, the battery structure 37 is arranged in the mold 29 so that the first main body 22A faces the third cavity 41 and the second surface 24c faces the fourth cavity 42. By introducing the resin into the mold 29 after the step and the second arrangement step, the second main body portion 22B is formed from the resin filled in the third cavity 41, and the fourth cavity 42 is filled. It includes a second forming step of forming the second overhang portion 23B with the resin. In the second arrangement step, the battery structure 37 is made of gold so that the thickness T41 of the third cavity 41 along the second direction is thicker than the thickness T42 of the fourth cavity 42 along the first direction. Place in mold 29. Therefore, the second main body portion 22B that can be formed relatively thick is provided so as to cover the first main body portion 22A that tends to be relatively thin, and the airtightness can be improved.

In the manufacturing method according to the present embodiment, in the first arrangement step, the cross-sectional area in the cross section intersecting (orthogonal) in the first direction of the first cavity 35 is the cross section along the first direction of the second cavity 36. By arranging the electrode laminate 24 in the mold 28 so as to be smaller than the cross-sectional area in the above, the first filling step may be completed after the second filling step is completed. Alternatively, in the first arrangement step, the second filling step is completed by arranging the electrode laminate 24 in the mold 28 so that the volume of the first cavity 35 is larger than the volume of the second cavity 36. After that, the first filling step may be completed. In this way, when the filling of the resin into the second cavity 36 is completed and then the filling of the resin into the first cavity 35 is completed to suppress the deformation of the electrode, at least the thickness, cross-sectional area, and volume of the cavity are at least. You can control one.

Subsequently, the action / effect will be explained based on the simulation result. 8 and 9 are diagrams showing a first simulation example. As shown in FIG. 8A, in this example, the thickness T35 of the first cavity 35 along the second direction and the thickness T36 of the second cavity 36 along the first direction are the same. And said. In that state, as shown in FIG. 9, resin was simultaneously introduced into the first cavity 35 and the second cavity 36 from the pair of resin introduction portions P1 separated from each other (resin was introduced into the mold 28 from the common gate). Introduced). The viscosity of the resin was, for example, about 10 Pa · sec to 1000 Pa · sec.

According to FIG. 9, it is understood that the resin M is preferentially advanced to the second cavity 36 rather than the first cavity 35. That is, according to this first simulation example, the filling of the resin M in the second cavity 36 can be completed before the filling of the resin M in the first cavity 35 (after the second filling step is completed). The first filling step can be completed). As a result, as shown in FIG. 8B, at the confluence point (weld line) between the resin M introduced from one resin introduction section P1 and the resin M introduced from the other resin introduction section P1. However, the generation of the resin flow from the first cavity 35 toward the second cavity 36 side (that is, the resin flow from the outer surface 24a side toward the first surface 24b side) was suppressed.

10 and 11 are diagrams showing a second simulation example. As shown in FIG. 10A, in this example, the thickness T35 of the first cavity 35 along the second direction is made thinner than the thickness T36 of the second cavity 36 along the first direction. .. In that state, as shown in FIG. 11, the resin was simultaneously introduced into the first cavity 35 and the second cavity 36 from the pair of resin introduction portions P1 (the resin was introduced into the mold 28 from the common gate).

According to FIG. 11, it is understood that the resin M is more preferentially advanced to the second cavity 36 than the first cavity 35, even when compared with the first simulation example. That is, according to this second simulation example, the filling of the resin M in the second cavity 36 can be completed more reliably (more reliably than the filling of the resin M in the first cavity 35). The first filling step can be completed after the filling step is completed). As a result, as shown in FIG. 10B, at the confluence point (weld line) between the resin M introduced from one resin introduction section P1 and the resin M introduced from the other resin introduction section P1. However, the generation of the resin flow from the first cavity 35 toward the second cavity 36 side (that is, the resin flow from the outer surface 24a side toward the first surface 24b side) was suppressed.

12 and 13 are diagrams showing a third simulation example. As shown in FIG. 12A, in this example, the thickness T35 of the first cavity 35 along the second direction is made thicker than the thickness T36 of the second cavity 36 along the first direction. .. In that state, as shown in FIG. 13, the resin was simultaneously introduced into the first cavity 35 and the second cavity 36 from the pair of resin introduction portions P1 (the resin was introduced into the mold 28 from the common gate).

According to FIG. 13, it can be seen that the resin M is preferentially advancing to the first cavity 35 rather than the second cavity 36. That is, according to this third simulation example, it is difficult to complete the filling of the resin M in the second cavity 36 before the filling of the resin M in the first cavity 35. As a result, as shown in FIG. 12B, at least the confluence point (weld line) of the resin M introduced from one resin introduction section P1 and the resin M introduced from the other resin introduction section P1. ), A resin flow from the first cavity 35 toward the second cavity 36 side (that is, a resin flow from the outer surface 24a side toward the first surface 24b side) was generated.

From the above simulation results, by controlling the thickness T35 of the first cavity 35 to be at least the thickness T36 of the second cavity 36 or less, the first cavity 35 is surely more than the filling of the resin. It was confirmed that the filling of the resin into the two cavities 36 can be completed first, and as a result, the deformation of the electrode can be suppressed.

The above-described embodiment describes one embodiment of the present invention. Therefore, the present invention is not limited to the above-mentioned manufacturing method of the power storage module 2 and the power storage module 2. The present invention may be considered to be an arbitrary modification of the above-mentioned manufacturing method of the power storage module 2 and the power storage module 2 without changing the gist of each claim.

2 ... Power storage module, 21A ... 1st resin part, 21B ... 2nd resin part, 22A ... 1st main body part, 22B ... 2nd main body part, 23A ... 1st overhang part, 23B ... 2nd overhang part, 24 ... Electrode laminate, 24a ... outer surface, 24b ... first surface, 24c ... second surface, 28 ... mold (first mold), 29 ... mold (second mold), 35 ... first cavity, 36 ... 2nd cavity, 41 ... 3rd cavity, 42 ... 4th cavity, T22A, T22B, T23A, T23B ... Thickness.

Claims (6)

A method for manufacturing a power storage module including an electrode laminate including a plurality of electrodes laminated along a first direction and a first resin portion for sealing the electrode laminate.
A first step of forming the first resin portion on the outer peripheral portion of the electrode laminate by injection molding of a resin using a first mold is provided.
The electrode laminate is
A first surface located at one end of the electrode laminate in the first direction, a second surface located at the other end of the electrode laminate in the first direction, and the first surface extending along the first direction. Including an outer surface connecting one surface and the second surface,
The first resin portion includes a first main body portion that covers the outer surface of the electrode laminate, and a first main body portion that extends from the first main body portion along the in-plane direction of the first surface of the electrode laminate. Including the overhang part,
When the electrode laminate is arranged inside, the first mold is connected to a first cavity that faces the outer surface of the electrode laminate and extends along the first direction, and the first cavity. A second cavity extending from the outer edge of the first surface of the electrode laminate along the in-plane direction of the first surface is formed between the electrode laminate and the electrode laminate.
The first step is
The electrode laminate is placed in the first mold so that the outer surface of the electrode laminate faces the first cavity and the first surface of the electrode laminate faces the second cavity. The first placement process to place and
After the first arrangement step, the resin is introduced into the first mold from the common gate to form the first main body portion from the resin filled in the first cavity and into the second cavity. The first forming step of forming the first overhang portion with the filled resin, and
Including
The first forming step is
The first filling step of filling the first cavity with the resin, and
The second filling step of filling the second cavity with the resin, and
Including
In the first forming step, the first filling step is completed after the second filling step is completed.
Manufacturing method of power storage module. In the first arrangement step, the thickness of the first cavity along the second direction orthogonal to the first direction is equal to or less than the thickness of the second cavity along the first direction. The electrode laminate is arranged in the first mold.
The method for manufacturing a power storage module according to claim 1. A second resin portion is formed on the outer peripheral portion of the battery structure including the electrode laminate and the first resin portion formed in the first step by injection molding of a resin using a second mold. With the second step further
The second resin portion includes a second main body portion that covers the first main body portion, and a second overhang portion that extends from the second main body portion along the in-plane direction of the second surface of the electrode laminate. And, including
When the battery structure is arranged inside, the second mold is connected to the third cavity and the third cavity that faces the first main body and extends along the first direction, and the electrodes are laminated. A fourth cavity extending from the outer edge of the second surface of the body along the in-plane direction of the second surface is formed between the battery structure and the fourth cavity.
The second step is
The battery structure is arranged in the second mold so that the first main body portion faces the third cavity and the second surface of the electrode laminate faces the fourth cavity. 2 placement process and
By introducing the resin into the second mold after the second arrangement step, the second main body portion is formed by the resin filled in the third cavity, and the fourth cavity is filled. The second forming step of forming the second overhang portion with the resin, and
Including
In the second arrangement step, the battery structure is formed so that the thickness of the third cavity along the second direction is thicker than the thickness of the fourth cavity along the first direction. Place in the second mold,
The method for manufacturing a power storage module according to claim 2. In the first arrangement step, the cross-sectional area of the first cavity in a cross section orthogonal to the first direction is smaller than the cross-sectional area of the second cavity in a cross section along the first direction. The electrode laminate is arranged in the first mold,
The method for manufacturing a power storage module according to any one of claims 1 to 3. In the first arrangement step, the electrode laminate is arranged in the first mold so that the volume of the first cavity is larger than the volume of the second cavity.
The method for manufacturing a power storage module according to any one of claims 1 to 4. An electrode laminate containing a plurality of electrodes laminated along the first direction, and
A first resin part and a second resin part for sealing the electrode laminate,
With
The electrode laminate has a first surface located at one end of the electrode laminate in the first direction, a second surface located at the other end of the electrode laminate in the first direction, and the electrode laminate in the first direction. Includes an outer surface that extends along and connects the first surface and the second surface.
The first resin portion includes a first main body portion that covers the outer surface of the electrode laminate, and a first main body portion that extends from the first main body portion along the in-plane direction of the first surface of the electrode laminate. Including the overhang part,
The second resin portion includes a second main body portion that covers the first main body portion, and a second overhang portion that extends from the second main body portion along the in-plane direction of the second surface of the electrode laminate. And, including
The thickness of the first main body portion along the second direction orthogonal to the first direction is equal to or less than the thickness of the first overhang portion along the first direction.
The thickness of the second main body portion along the second direction is thicker than the thickness of the second overhang portion along the first direction.
Power storage module.

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