Manufacturing method of bipolar type energy storage module

Abstract

To provide a manufacturing method of a bipolar type energy storage module that can improve airtightness when sealing a liquid filling port after electrolyte is poured through the liquid filling port surrounded by a liquid filling port frame.SOLUTION: A manufacturing method of a bipolar type energy storage module disclosed herein connects a liquid injection connector 120 to a liquid injection port frame of a resin sealing member 110 including a liquid injection port 102 for injecting an electrolyte into an internal space 114 between adjacent bipolar electrodes 112 in an electrode stack 118, a protruding opening 106 protruding from the liquid injection port, and a liquid injection port frame 104 surrounding the periphery of the protruding opening, and injects an electrolyte into the internal space through the protruding opening and the liquid injection port via the liquid injection connector. After the liquid injection, a heating and pressing member 130 is pressed against the protruding opening to cause the resin originating from the protruding opening to flow into the liquid injection port and then cooled, thereby forming a liquid injection port sealing part 116 that seals the liquid injection port.SELECTED DRAWING: Figure 5

Description

Technical Field

[0001] The present disclosure relates to a method for manufacturing a bipolar power storage module.

Background Art

[0002] A power storage module is known that includes an electrode laminate in which a plurality of electrodes are laminated via a separator, a case that holds the electrode laminate, and an electrolytic solution accommodated between adjacent electrodes of the electrode laminate. In such a power storage module, after the electrolytic solution is injected into the accommodation space of the electrode laminate through a liquid injection port provided in the case that accommodates the electrode laminate, a sealing member is attached to the liquid injection port to seal the power storage module (see, for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] As a method for sealing a power storage module, there is a method of providing a liquid injection port frame around the liquid injection port for injecting an electrolytic solution and sealing the liquid injection port frame by lamination or the like. FIG. 6 shows an example of a method for sealing the liquid injection port 102. The liquid injection port frame 104 is made of resin. After injecting the electrolytic solution from the liquid injection port 102, when sealing the resin-made liquid injection port frame 104 with the laminate 122, as shown in FIG. 6, there is a method of pressing and heating the hot plate 130 in contact with the laminate 122 against the liquid injection port frame 104 for heat welding. In this case, the end portion of the liquid injection port frame 104 may melt and be pushed into the electrode laminate 118 side. Then, the volume of the region surrounded by the liquid injection port frame 104 and the laminate 122 becomes smaller by, for example, ΔV, and the internal pressure of the region rises. Since the gas existing in the region surrounded by the liquid injection port frame 104 and the laminate 122 tries to escape to the outside due to the rise in the internal pressure, a hole may be formed in the welded portion 104A, and the sealing performance of the power storage module may deteriorate.

[0005] An object of the present disclosure is to provide a method for manufacturing a bipolar type power storage module that can improve the sealing performance when sealing a liquid injection port after injecting an electrolytic solution from the liquid injection port surrounded by a liquid injection port frame.

Means for Solving the Problems

[0006] Means for solving the above problems include the following embodiments. <1> A method for manufacturing a bipolar type power storage module including an electrode laminate in which a plurality of bipolar electrodes are laminated via a separator, a sealing member for sealing a peripheral portion of the electrode laminate, and an electrolytic solution, a liquid injection step of connecting a liquid injection connector to the liquid injection port frame of a resin sealing member including a liquid injection port for injecting the electrolytic solution into an internal space between adjacent bipolar electrodes, a protruding opening protruding from the liquid injection port, and a liquid injection port frame surrounding the periphery of the protruding opening, and injecting the electrolytic solution into the internal space through the protruding opening and the liquid injection port via the liquid injection connector; a sealing step of forming a liquid injection port sealing portion for sealing the liquid injection port by pressing a heating and pressing member against the protruding opening after the liquid injection step to allow the resin derived from the protruding opening to flow into the liquid injection port and then cooling; A method for manufacturing a bipolar type power storage module including the above steps. <2> The method for manufacturing a bipolar power storage module according to claim 1, further comprising a step of removing the liquid injection port frame after the sealing step. <3> When the target thickness of the liquid injection port sealing portion is T mm, the area of the liquid injection port when viewed from the direction in which the protruding opening protrudes is S mm 2 and the volume of the protruding opening is C mm 3 The method for manufacturing a bipolar power storage module according to claim 1 or claim 2, wherein the protruding opening is designed to satisfy the relationship of the following formula (1). C≧T×S ···(1)

Advantages of the Invention

[0007] According to the present disclosure, there is provided a method for manufacturing a bipolar power storage module capable of improving the sealing performance when sealing a liquid injection port after injecting an electrolytic solution from the liquid injection port surrounded by a liquid injection port frame.

Brief Description of the Drawings

[0008]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Embodiments for Carrying Out the Invention

[0009] Hereinafter, with reference to the drawings, a method for manufacturing a bipolar type power storage module according to the present disclosure will be described. In the drawings, the same or corresponding parts are denoted by the same reference numerals, and the reference numerals are appropriately omitted in the same drawing. In the present disclosure, the term "process" includes not only an independent process but also a process that cannot be clearly distinguished from other processes as long as the intended purpose of the process is achieved. Further, in the present disclosure, the bipolar type power storage module may refer to not only a form in which an electrolytic solution is housed and sealed in the internal space of the electrode laminate, but also a form before the electrolytic solution is housed and sealed in each internal space.

[0010] A bipolar type power storage module manufactured by a method for manufacturing a bipolar type power storage module according to the present disclosure (which may be referred to as a "power storage module" in this specification) includes an electrode laminate in which a plurality of bipolar electrodes are laminated via a separator, a sealing member that seals the peripheral edge of the electrode laminate, and an electrolytic solution housed between the bipolar electrodes adjacent to each other in the lamination direction in the electrode laminate. FIG. 1 is a schematic diagram showing an example of the internal configuration of a power storage module in a bipolar type power storage device. The details of the structure of the power storage module shown in FIG. 1 will be described later.

[0011] The method for manufacturing a bipolar type power storage module according to the present disclosure includes a liquid injection step of injecting an electrolytic solution into the internal space of the electrode laminate from a liquid injection port surrounded by a liquid injection port frame, and a sealing step of sealing the liquid injection port after the liquid injection step. The method for manufacturing a bipolar type power storage module according to the present disclosure may include a liquid injection port frame removal step of removing the liquid injection port frame after the sealing step. Hereinafter, each step will be described with reference to FIGS. 2 to 5. Note that the electrode laminate and the like are shown in a simplified manner in FIGS. 2 to 5.

[0012] <Liquid injection step> FIG. 2 is a schematic diagram showing the periphery of a resin sealing member at one end of an electrode laminate 118 of a bipolar type power storage module 100 manufactured by a method for manufacturing a bipolar type power storage module according to the present disclosure. The electrode laminate 118 has a plurality of bipolar electrodes 112 laminated via a separator (not shown). The peripheral portions of each bipolar electrode 112 are supported by a support member 108. An internal space 114 for accommodating an electrolytic solution is provided between the bipolar electrodes 112 adjacent to each other in the lamination direction.

[0013] The resin sealing member 110 includes a liquid injection port 102 for injecting the electrolytic solution, a protruding opening 106 (which may be referred to as a "rib" in this specification) protruding outward from the liquid injection port 102, and a liquid injection port frame 104 surrounding the periphery of the rib 106. The liquid injection port 102 is formed across the support member 108 and the sealing member 110 and communicates with the rib 106 and the internal space 114. By injecting the electrolytic solution from the rib 106, the electrolytic solution is supplied to the internal space between the two bipolar electrodes 112. In FIG. 2, three liquid injection ports 102 are shown, but the liquid injection port 102 is provided for each internal space 114 of the adjacent bipolar electrodes 112. Specifically, in the power storage module 100 shown in FIG. 1, since there are 12 bipolar electrodes 112 and 11 internal spaces 114 between the adjacent bipolar electrodes 112, there are 11 liquid injection ports 102. Therefore, the eight liquid injection ports not shown and the ribs and liquid injection port frames corresponding to each liquid injection port are provided at positions different from those of the liquid injection port 102 and the like shown in the figure.

[0014] Examples of the resin constituting the resin sealing member 110 include polyethylene, polystyrene, acrylonitrile-butadiene-styrene copolymer synthetic resin (ABS resin), modified polypropylene, and acrylonitrile styrene resin. The above resin is also mentioned as a constituent material of the support member 108. The support member 108 can be regarded as a part of the sealing member.

[0015] FIG. 3 is a schematic diagram showing a state in which a liquid injection connector 120 is connected to a liquid injection port frame 104. As shown in FIG. 3, in the liquid injection step, the liquid injection connector 120 is connected to the liquid injection port frame 104 of the resin sealing member 110. The liquid injection connector 120 is connected to a tank (not shown) containing an electrolytic solution, and the electrolytic solution can be fed by a pump (not shown). The electrolytic solution is injected into the internal space 114 through the rib 106 and the liquid injection port 102 via the liquid injection connector 120 connected to the liquid injection port frame 104.

[0016] Examples of the electrolytic solution include those containing a non-aqueous solvent and a lithium salt. Examples of the lithium salt include LiClO4, LiAsF6, LiPF6, LiBF4, LiCF3SO3, LiN(FSO2)2, LiN(CF3SO2)2, and the like. Examples of the non-aqueous solvent include cyclic carbonates, cyclic esters, chain carbonates, chain esters, ethers, and the like. The electrolytic solution may contain an additive (for example, lithium bis(oxalato)borate, etc.).

[0017] <Sealing Process> After the liquid injection process, the injection port 102 is sealed with the resin derived from the rib 106. FIG. 4 is a schematic view showing an example of a method of sealing by pressing a heating and pressing member 130 against the rib 106 in one injection port frame 104. FIG. 5 is a schematic view showing a state where the injection port 102 is sealed. After the liquid injection process, as shown in FIG. 4, the heating and pressing member 130 is pressed against the rib 106 to allow the resin derived from the rib 106 to flow into the injection port 102. The heating and pressing member 130 may be selected according to the shape and size of the rib 106 and the injection port frame 104, and examples thereof include a plate-shaped heating body (hot plate) or a rod-shaped heating body. The temperature of the heating and pressing member 130 may be set according to the melting point or glass transition temperature of the resin constituting the rib 106. Specifically, the temperature of the heating and pressing member 130 is set to the temperature at which the rib 106 melts or softens. However, if the temperature is too low, the resin derived from the rib 106 is difficult to flow into the injection port 102, and if the temperature is too high, portions of the sealing member 110 other than the rib 106 may melt or soften and deform. From this perspective, the heating and pressing member 130 may be set to a temperature about 10°C to 50°C higher than the melting point or glass transition temperature of the resin constituting the rib 106. Since the heating and pressing member 130 is separated from the resin sealing member 110 and cooled, as shown in FIG. 5, an injection port sealing portion 116 for sealing the injection port 102 is formed, and the injection port 102 is blocked with resin.

[0018] The thickness of the injection port sealing portion 116 is not particularly limited. However, since the injection port sealing portion 116 is formed by the melted rib 106 flowing into the injection port 102 and solidifying, the thickness of the injection port sealing portion 116 depends on the area of the injection port 102 and the volume of the rib 106. When the target thickness of the injection port sealing portion 116 is T mm, the area of the injection port 102 as viewed from the direction in which the rib 106 protrudes is S mm 2 and the volume of the rib 106 is C mm 3 it is preferable to design the rib 106 so as to satisfy the relationship of the following formula (1). C≧T×S ···(1) From the perspective of reliably sealing the injection port 102, the thickness of the injection port sealing portion 116 is preferably 1 mm or more.

[0019] <Injection port frame removal process> After the sealing process, since the liquid injection port frame 104 is no longer needed, the liquid injection port frame 104 may be removed. For example, cut the liquid injection port frame 104 along the line A-A in FIG. 5 with a cutter or the like. By removing the liquid injection port frame 104, the overall size of the power storage module can be reduced, and the volume efficiency can be improved.

[0020] Next, the details of the structure of the power storage module shown in FIG. 1 will be described. The method for manufacturing a bipolar type power storage module according to the present disclosure can be applied to the manufacture of a power storage module 4 having a structure as shown in FIG. 1. However, the power storage module 4 shown in FIG. 1 is an example (one embodiment), and the method for manufacturing a bipolar type power storage module according to the present disclosure is not limited thereto. Note that the power storage module 4 shown in FIG. 1 is denoted by different reference numerals even if it is the same or corresponding member in FIGS. 2 to 5.

[0021] The power storage module 4 includes an electrode laminate 11, a resin sealing body 12 that seals the electrode laminate 11, and an electrolytic solution (not shown). The power storage module 4 is formed in a rectangular parallelepiped shape, for example.

[0022] The electrode laminate 11 includes a plurality of electrodes laminated along the lamination direction D via a separator 13, and current collectors (metal plates 20A, 20B) located at the lamination ends of the electrode laminate 11. The plurality of electrodes include a negative terminal electrode 18, a positive terminal electrode 19, and a plurality of bipolar electrodes 14 laminated between the negative terminal electrode 18 and the positive terminal electrode 19. The laminate of the plurality of bipolar electrodes 14 is disposed between the negative terminal electrode 18 and the positive terminal electrode 19. The power storage module 4 has a structure in which a plurality of cells are stacked in the lamination direction D of the bipolar electrodes 14.

[0023] The bipolar electrode 14 includes a metal plate 15 as a current collector including one surface 15a and the other surface 15b provided on the opposite side of the one surface 15a, a positive electrode 16 provided on the one surface 15a, and a negative electrode 17 provided on the other surface 15b. The one surface 15a is a surface facing one side in the stacking direction D, for example, facing upward in the direction of gravity. The other surface 15b is a surface facing the other side in the stacking direction D, for example, facing downward in the direction of gravity. The positive electrode 16 is a positive electrode active material layer formed by coating the positive electrode active material on the metal plate 15. The negative electrode 17 is a negative electrode active material layer formed by coating the negative electrode active material on the metal plate 15. In the electrode laminate 11, the positive electrode 16 of one bipolar electrode 14 faces the negative electrode 17 of another bipolar electrode 14 adjacent to one side in the stacking direction D with the separator 13 interposed therebetween. In the electrode laminate 11, the negative electrode 17 of one bipolar electrode 14 faces the positive electrode 16 of another bipolar electrode 14 adjacent to the other side in the stacking direction D with the separator 13 interposed therebetween.

[0024] The negative terminal electrode 18 includes the metal plate 15 and the negative electrode 17 provided on the other surface 15b of the metal plate 15. The negative terminal electrode 18 is disposed on one end side in the stacking direction D such that the other surface 15b faces the central side in the stacking direction D in the electrode laminate 11. A metal plate 20A is further stacked on the one surface 15a of the metal plate 15 of the negative terminal electrode 18 and is electrically connected to one conductive plate 5 adjacent to the power storage module 4 through this metal plate 20A. The negative electrode 17 provided on the other surface 15b of the metal plate 15 of the negative terminal electrode 18 faces the positive electrode 16 of the bipolar electrode 14 at one end in the stacking direction D with the separator 13 interposed therebetween.

[0025] The positive terminal electrode 19 has a metal plate 15 and a positive electrode 16 provided on one surface 15a of the metal plate 15. The positive terminal electrode 19 is arranged on the other end side in the stacking direction D such that one surface 15a faces the central side in the stacking direction D in the electrode laminate 11. A metal plate 20B is further stacked on the other surface 15b of the metal plate 15 of the positive terminal electrode 19, and is electrically connected to the other conductive plate 5 adjacent to the power storage module 4 through this metal plate 20B. The positive electrode 16 provided on one surface 15a of the metal plate 15 of the positive terminal electrode 19 faces the negative electrode 17 of the bipolar electrode 14 at the other end in the stacking direction D through the separator 13.

[0026] The metal plate 15 is made of a metal such as, for example, Al, SUS, Ni, Cu, etc. Each metal plate 15 is one of the metal plates included in the electrode laminate 11. The edge 15c of the metal plate 15 forms a rectangular frame shape and forms a part of the uncoated region 15d where the positive electrode active material and the negative electrode active material are not coated. Examples of the positive electrode active material constituting the positive electrode 16 include oxide active materials. Examples of the oxide active materials include rock salt layer type active materials such as LiCoO2, LiMnO2, LiNiO2, LiVO2, LiNi 1 / 3 Co 1 / 3 Mn 1 / 3 O2 and other spinel type active materials such as LiMn2O4, Li(Ni 0.5 Mn 1.5 )O4, and olivine type active materials such as LiFePO4, LiMnPO4, LiNiPO4, LiCuPO4. Examples of the negative electrode active material constituting the negative electrode 17 include carbon active materials, oxide active materials, and metal active materials. In this embodiment, the formation region of the negative electrode 17 on the other surface 15b of the metal plate 15 is slightly larger than the formation region of the positive electrode 16 on one surface 15a of the metal plate 15. The electrode laminate 11 has a plurality of stacked metal plates 15, 20A, 20B.

[0027] Separator 13 is a member for preventing short - circuit between metal plates 15 and is formed, for example, in a sheet shape. Examples of the separator 13 include a porous film made of a polyolefin - based resin such as polyethylene (PE) or polypropylene (PP), a woven or non - woven fabric made of polypropylene, methyl cellulose, etc. The separator 13 may be reinforced with a vinylidene fluoride resin compound. Note that the separator 13 is not limited to a sheet shape, and a bag - shaped one may be used.

[0028] Metal plates 20A and 20B are members substantially the same as the metal plate 15 and are made of metals such as Al, SUS, Ni, Cu, etc. Metal plates 20A and 20B are both one of the metal plates included in the electrode laminate 11. Metal plates 20A and 20B form uncoated electrodes on which neither the positive electrode active material layer nor the negative electrode active material layer is coated on one surface 20a and the other surface 20b. That is, metal plates 20A and 20B are uncoated electrodes on which no active material layer is provided on both sides.

[0029] Due to the metal plate 20A, the negative terminal electrode 18 is arranged between the metal plate 20A and the bipolar electrode 14 along the stacking direction D. The other surface 20b of the metal plate 20A and the one surface 15a of the metal plate 15 of the negative terminal electrode 18 are electrically connected by directly contacting each other without any intervening material. Due to the metal plate 20B, the positive terminal electrode 19 is arranged between the metal plate 20B and the bipolar electrode 14 along the stacking direction D. The one surface 20a of the metal plate 20B and the other surface 15b of the metal plate 15 of the positive terminal electrode 19 are electrically connected by directly contacting each other without any intervening material.

[0030] In the electrode laminate 11, the central region of the electrode laminate 11 (the region where the active material layer is arranged in the bipolar electrode 14, the negative terminal electrode 18, and the positive terminal electrode 19) bulges in the stacking direction D compared to the surrounding region. For this reason, the metal plates 20A and 20B bend in a direction in which the central regions of the metal plates 20A and 20B are separated from each other. The central regions of the one surface 20a of the metal plate 20A and the other surface 20b of the metal plate 20B come into contact with the conductive plate 5.

[0031] The sealing body 12 is formed, for example, of an insulating resin into a rectangular cylindrical shape as a whole. The sealing body 12 is formed, for example, into a rectangular cylindrical shape having a pair of short side portions 12a and a pair of long side portions 12b. The sealing body 12 is provided so as to surround the side surface 11a of the electrode laminate 11. The sealing body 12 holds the edge portion 15c on the side surface 11a.

[0032] The sealing body 12 includes a plurality of frame-shaped first sealing portions 21 (resin portions) provided respectively at the edge portions of the metal plates included in the electrode laminate 11 (that is, the edge portion 15c of the metal plate 15 and the edge portions 20c of the metal plates 20A and 20B), and a second sealing portion 22 that surrounds the first sealing portion 21 from the outside along the side surface 11a and is coupled to each of the first sealing portions 21. The first sealing portion 21 and the second sealing portion 22 are, for example, insulating resins, and examples of the constituent materials of the resin include polypropylene (PP), polyphenylene sulfide (PPS), modified polyphenylene ether (modified PPE), and the like.

[0033] The first sealing portion 21 is continuously provided over the entire circumference of the edge portion 15c of the metal plate 15 and the edge portions 20c of the metal plates 20A and 20B, and forms a rectangular frame shape when viewed from the stacking direction D. The first sealing portion 21 and the metal plate 15, and the first sealing portion 21 and the metal plates 20A and 20B are hermetically joined respectively. The first sealing portion 21 extends outward beyond the edge portion 15c of the metal plate 15 or the edge portions 20c of the metal plates 20A and 20B when viewed from the stacking direction D. The first sealing portion 21 includes an outer portion 21a that projects outward beyond the edge of the metal plate 15 or the metal plates 20A and 20B, and an inner portion 21b that is located inward of the edge of the metal plate 15 or the metal plates 20A and 20B. A welding layer 23 is formed at the tip (outer edge portion) of the outer portion 21a of the first sealing portion 21.

[0034] The plurality of first sealing portions 21 include a plurality of first sealing portions 21A provided on the bipolar electrode 14 and the positive terminal electrode 19, a first sealing portion 21B provided on the negative terminal electrode 18, a first sealing portion 21C provided on the metal plate 20A, and first sealing portions 21D and 21E provided on the metal plate 20B.

[0035] The first sealing part 21A is joined to one surface 15a of the metal plate 15 of the bipolar electrode 14 and the positive terminal electrode 19. The inner part 21b of the first sealing part 21A is located between the edges 15c of the metal plates 15 adjacent to each other in the stacking direction D. The region where the edge 15c on one surface 15a of the metal plate 15 and the first sealing part 21A overlap becomes the bonding region between the metal plate 15 and the first sealing part 21A.

[0036] In this embodiment, the first sealing part 21A is formed in a two-layer structure by folding one film in half. The outer edge part of the first sealing part 21A embedded in the second sealing part 22 is the folded-back part (bent part) of the film. The first layer of the film constituting the first sealing part 21A is joined to one surface 15a. The inner edge of the second layer of the film is located outside the inner edge of the first layer of the film and forms a stepped part on which the separator 13 is placed. The inner edge of the second layer of the film is located inside the edge of the metal plate 15.

[0037] The first sealing part 21B is joined to one surface 15a of the metal plate 15 of the negative terminal electrode 18. The inner part 21b of the first sealing part 21B is located between the edge 15c of the metal plate 15 of the negative terminal electrode 18 adjacent to each other in the stacking direction D and the edge 20c of the metal plate 20A. The region where the edge 15c on one surface 15a of the metal plate 15 and the inner part 21b of the first sealing part 21B overlap becomes the bonding region between the metal plate 15 and the first sealing part 21B. The first sealing part 21B is also joined to the other surface 20b of the metal plate 20A. The region where the edge 20c on the other surface 20b of the metal plate 20A and the first sealing part 21B overlap becomes the bonding region between the metal plate 20A and the first sealing part 21B. In this embodiment, the first sealing part 21B is also joined to the edge 20c on the other surface 20b of the metal plate 20A.

[0038] The first sealing portion 21C is joined to one surface 20a (outer surface) of the metal plate 20A. The region where the edge 20c on one surface 20a of the metal plate 20A overlaps with the first sealing portion 21C becomes the bonding region between the metal plate 20A and the first sealing portion 21C. One surface 20a of the metal plate 20A has an exposed surface 20d that is exposed from the first sealing portion 21C. The conductive plate 5 is disposed in contact with the exposed surface 20d.

[0039] In the present embodiment, the outer edges of the first sealing portions 21B and 21C embedded in the second sealing portion 22 are continuous. That is, the first sealing portions 21B and 21C are formed by folding a single film in two with the edge 20c of the metal plate 20A sandwiched therebetween. The outer edges of the first sealing portions 21B and 21C are the folded-back portions of the film. The film constituting the first sealing portions 21B and 21C is joined to the edge 20c on both the one surface 20a and the other surface 20b of the metal plate 20A.

[0040] The first sealing portion 21D is joined to one surface 20a of the metal plate 20B. The inner portion 21b of the first sealing portion 21D is located between the edge 15c of the metal plate 15 of the positive terminal electrode 19 adjacent to each other in the stacking direction D and the edge 20c of the metal plate 20B. The region where the edge 20c on one surface 20a of the metal plate 20B overlaps with the first sealing portion 21D becomes the bonding region between the metal plate 20B and the first sealing portion 21D.

[0041] The first sealing portion 21E is disposed at the edge 20c on the other surface 20b (outer surface) of the metal plate 20B. In the present embodiment, the first sealing portion 21E is not joined to the metal plate 20B. The other surface 20b of the metal plate 20B has an exposed surface 20d that is exposed from the first sealing portion 21E. The conductive plate 5 is disposed in contact with the exposed surface 20d.

[0042] In this embodiment, the outer edges of the first sealing portions 21D and 21E embedded in the second sealing portion 22 are continuous. That is, the first sealing portions 21D and 21E are formed by folding a single film in two with the edge 20c of the metal plate 20B sandwiched therebetween. The outer edges of the first sealing portions 21D and 21E are the folded-back portions of the film. The film constituting the first sealing portions 21D and 21E is joined to the edge 20c on one surface 20a of the metal plate 20B.

[0043] A plurality of internal spaces V are provided in the electrode laminate 11. Each internal space V is provided between adjacent metal plates. The internal space V is a space hermetically and liquid-tightly partitioned by the metal plate and the sealing body 12 between adjacent metal plates in the stacking direction D. An electrolytic solution (not shown) is accommodated in this internal space V.

[0044] In the manufacture of the power storage module having the above-described structure, when sealing after accommodating the electrolytic solution in the internal space V, by applying the manufacturing method of the bipolar type power storage module according to the present disclosure, a power storage module with high sealing performance can be manufactured.

Explanation of Reference Numerals

[0045] 4 Power storage module, 11 Electrode laminate, 12 Sealing body, 14 Bipolar electrode, 102 Liquid injection port, 104 Liquid injection port frame, 106 Protruding opening (rib), 108 Support member, 110 Resin sealing member, 112 Bipolar electrode, 114 Internal space, 116 Liquid injection port sealing portion, 118 Electrode laminate, 120 Liquid injection connector

Claims

1. A method for manufacturing a bipolar type power storage module including: an electrode laminate in which a plurality of bipolar electrodes are laminated via a separator; a sealing member that seals a peripheral portion of the electrode laminate; and an electrolytic solution, a liquid injection step of connecting a liquid injection connector to a liquid injection port frame of a resin sealing member including a liquid injection port for injecting the electrolytic solution into an internal space between adjacent bipolar electrodes, a protruding opening protruding from the liquid injection port, and a liquid injection port frame surrounding the periphery of the protruding opening, and injecting the electrolytic solution into the internal space through the protruding opening and the liquid injection port via the liquid injection connector; a sealing step of forming a liquid injection port sealing portion for sealing the liquid injection port by pressing a heating and pressing member against the protruding opening after the liquid injection step to cause the resin derived from the protruding opening to flow into the liquid injection port and then cooling; A method for manufacturing a bipolar type power storage module including the above steps.

2. The method for manufacturing a bipolar type power storage module according to claim 1, further including a liquid injection port frame removal step of removing the liquid injection port frame after the sealing step.

3. The target thickness of the liquid injection port sealing portion is T mm, and the area of the liquid injection port when viewed from the direction in which the protruding opening protrudes is S mm ２ , the volume of the protruding opening is C mm ３ The method for manufacturing a bipolar type power storage module according to claim 1 or claim 2, wherein the protruding opening is designed so as to satisfy the relationship of the following formula (1). C≧T×S ・・・(1)

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