Method for manufacturing an energy storage module and an energy storage module

Abstract

To provide a manufacturing method for a power storage module, and a power storage module, in which the insulation test can be carried out safely while the tact time and the power cost are reduced.SOLUTION: A manufacturing method for a power storage module 1 includes a stacking step of stacking a plurality of bipolar electrodes 100, a positive electrode terminal electrode 200, and a negative electrode terminal electrode 300, a sealing step of forming a sealing member 20 at a peripheral part of each of the electrodes 100, 200, and 300 in an electrode multilayer body 10 so as to form the sealing member 20 that seals a space R while keeping a liquid injection member 30, an insulating testing step of testing the insulation state between a positive electrode non-coated part 112b and a negative electrode non-coated part 113b by applying a voltage to the electrode multilayer body 10 in a state where the pressure inside the sealing member 20 is reduced from the liquid injection member 30, a liquid injection step of, after the insulating testing step, supplying an electrolyte solution from the liquid injection member 30 to the sealing member 20, and a charging step of charging the electrode multilayer body 10.SELECTED DRAWING: Figure 1

Description

Technical Field

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

Background Art

[0002] Japanese Patent Application Laid-Open No. 2019-87414 discloses a bipolar battery in which a plurality of bipolar electrodes, a positive terminal electrode, and a negative terminal electrode are laminated via a separator. In this bipolar battery, uncoated portions of the electrode foils of each electrode where no active material is provided face each other with a gap therebetween.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the bipolar battery described in Japanese Patent Application Laid-Open No. 2019-87414, the inside of the bipolar battery may be depressurized until the pressure inside the bipolar battery is less than atmospheric pressure. In this case, the uncoated portions of the electrode foil of the positive terminal electrode and the uncoated portions of the electrode foil of the negative terminal electrode are deformed so as to be recessed inward in the stacking direction due to the differential pressure between the inside and the outside of the bipolar battery. If there is a foreign object such as a metal piece between each uncoated portion deformed inward and the uncoated portion facing the uncoated portion, there is a concern that the foreign object penetrates the separator and the pair of uncoated portions facing each other come into contact with each other through the foreign object, that is, there is a concern that an internal short circuit may occur.

[0005] The presence or absence of this internal short circuit can be detected after the manufacture of the bipolar battery by inspecting the insulation state between the uncoated portion of the positive or negative terminal electrode and the uncoated portion facing it. This insulation inspection is performed by applying voltage to the bipolar battery. However, if an internal short circuit has occurred in the bipolar battery, applying voltage may cause the bipolar battery to enter a state known as thermal runaway.

[0006] Therefore, it is conceivable to perform the above insulation test after the bipolar battery has been almost completely discharged following its manufacture. However, doing so would increase the cycle time and also increase the electricity costs required for manufacturing the bipolar battery.

[0007] The purpose of this disclosure is to provide a method for manufacturing an energy storage module and an energy storage module that can safely perform insulation testing while reducing cycle time and power costs. [Means for solving the problem]

[0008] A method for manufacturing an energy storage module according to one aspect of the present disclosure comprises: an electrode stack including a plurality of bipolar electrodes stacked on top of each other; a positive terminal electrode disposed on one side of the plurality of bipolar electrodes in the stacking direction of the plurality of bipolar electrodes; and a negative terminal electrode disposed on the other side of the plurality of bipolar electrodes in the stacking direction; a sealing member that seals the space between a pair of electrodes adjacent to each other in the stacking direction of the electrode stack; and a liquid injection member disposed within the sealing member for supplying an electrolyte to the electrode stack, comprising: a stacking step of stacking the plurality of bipolar electrodes, the positive terminal electrode, and the negative terminal electrode such that the uncoated positive electrode portion of one electrode and the uncoated negative electrode portion of the other electrode of the pair of electrodes adjacent to each other in the stacking direction face each other; and opening the space between the uncoated positive electrode portion and the uncoated negative electrode portion to the outside. The method comprises: a sealing step of forming a sealing member on the periphery of each electrode in the electrode stack such that a sealing member is formed that seals the space while holding the liquid injection member to be released; an insulation inspection step of applying a voltage to the electrode stack while reducing the pressure inside the sealing member from the liquid injection member such that the uncoated portion of the positive electrode in the positive electrode terminal electrode is recessed toward the inside in the stacking direction, and the uncoated portion of the negative electrode in the negative electrode terminal electrode is recessed toward the inside in the stacking direction, thereby inspecting the insulation state between the uncoated portion of the positive electrode in the positive electrode terminal electrode and the uncoated portion of the negative electrode facing the uncoated portion of the positive electrode terminal electrode, and the insulation state between the uncoated portion of the negative electrode in the negative electrode terminal electrode and the uncoated portion of the positive electrode facing the uncoated portion of the negative electrode; a liquid injection step of supplying the electrolyte from the liquid injection member into the sealing member after the insulation inspection step; and a charging step of charging the electrode stack.

[0009] A battery storage module according to one aspect of the present disclosure comprises an electrode stack including a plurality of bipolar electrodes stacked on top of each other, a positive terminal electrode disposed on one side of the plurality of bipolar electrodes in the stacking direction of the plurality of bipolar electrodes, and a negative terminal electrode disposed on the other side of the plurality of bipolar electrodes in the stacking direction, a sealing member that seals between a pair of electrodes adjacent to each other in the stacking direction of the electrode stack, and a liquid injection member disposed within the sealing member for supplying an electrolyte to the electrode stack, wherein each of the plurality of bipolar electrodes has a current collector including a positive electrode current collector foil and a negative electrode current collector foil, a positive electrode active material layer provided on the positive electrode current collector foil in the current collector, and a negative electrode active material layer provided on the negative electrode current collector foil in the current collector, and the positive terminal electrode has a positive electrode current collector foil and a positive electrode active material layer provided on the positive electrode current collector foil, and The negative electrode terminal electrode comprises a negative electrode foil and a negative electrode active material layer provided on the negative electrode foil. The positive electrode current collector foil in each current collector and the positive electrode current collector foil in the positive electrode terminal electrode each comprises a positive electrode coated portion on which the positive electrode active material layer is provided and a positive electrode uncoated portion on which the positive electrode active material layer is not provided. The negative electrode current collector foil in each current collector and the negative electrode current collector foil in the negative electrode terminal electrode each comprises a negative electrode coated portion on which the negative electrode active material layer is provided and a negative electrode uncoated portion facing the positive electrode uncoated portion in the stacking direction and on which the negative electrode active material layer is not provided. The sealing member seals the space formed between the positive electrode uncoated portion of one electrode and the negative electrode uncoated portion of the other electrode in a pair of electrodes adjacent to each other in the stacking direction when the pressure is lower than atmospheric pressure. The liquid injection member communicates the space with the outside of the sealing member. [Effects of the Invention]

[0010] According to this disclosure, it is possible to provide a method for manufacturing an energy storage module and an energy storage module that can safely perform insulation testing while reducing cycle time and power costs. [Brief explanation of the drawing]

[0011] [Figure 1]This is a schematic cross-sectional view showing an energy storage module in one embodiment of the present disclosure. [Figure 2] This is an enlarged view of the area indicated by the solid line II in Figure 1. [Figure 3] This is a cross-sectional view of the liquid injection member. [Modes for carrying out the invention]

[0012] Embodiments of this disclosure will be described with reference to the drawings. In the drawings referred to below, the same or equivalent components are given the same number.

[0013] Figure 1 is a schematic cross-sectional view showing an energy storage module in one embodiment of the present disclosure. As shown in Figure 1, the energy storage module 1 comprises an electrode stack 10, a sealing member 20, and a liquid injection member 30.

[0014] The electrode stack 10 includes a plurality of bipolar electrodes 100, a positive terminal electrode 200, a negative terminal electrode 300, and a plurality of separators 400.

[0015] Multiple bipolar electrodes 100 are stacked on top of each other. Each bipolar electrode 100 has a current collector 110, a positive electrode active material layer 120, and a negative electrode active material layer 130.

[0016] The current collector 110 is made of metal and is formed, for example, in a rectangular shape. The current collector 110 has a positive electrode current collector foil 112 and a negative electrode current collector foil 113. The positive electrode current collector foil 112 is made of, for example, aluminum. The negative electrode current collector foil 113 is made of, for example, copper foil. The negative electrode current collector foil 113 is bonded to the positive electrode current collector foil 112 by a conductive adhesive.

[0017] The positive electrode active material layer 120 is provided on one surface of the current collector 110, that is, on the surface of the positive electrode current collector foil 112. The negative electrode active material layer 130 is provided on the other surface of the current collector 110, that is, on the surface of the negative electrode current collector foil 113.

[0018] The plurality of bipolar electrodes 100 are stacked such that the positive electrode active material layer 120 in one bipolar electrode 100 and the negative electrode active material layer 130 in the bipolar electrode 100 adjacent to the one bipolar electrode 100 face each other.

[0019] The positive electrode terminal electrode 200 is disposed on one side (the upper side in FIG. 1) of the plurality of bipolar electrodes 100 in the stacking direction. The positive electrode terminal electrode 200 has a positive electrode current collector foil 112 and a positive electrode active material layer 120 provided on the positive electrode current collector foil 112. The configurations of the positive electrode current collector foil 112 and the positive electrode active material layer 120 in the positive electrode terminal electrode 200 are the same as the configurations of the positive electrode current collector foil 112 and the positive electrode active material layer 120 in the bipolar electrode 100.

[0020] The negative electrode terminal electrode 300 is disposed on the other side (the lower side in FIG. 1) of the plurality of bipolar electrodes 100 in the stacking direction. The negative electrode terminal electrode 300 has a negative electrode current collector foil 113 and a negative electrode active material layer 130 provided on the negative electrode current collector foil 113. The configurations of the negative electrode current collector foil 113 and the negative electrode active material layer 130 in the negative electrode terminal electrode 300 are the same as the configurations of the negative electrode current collector foil 113 and the negative electrode active material layer 130 in the bipolar electrode 100.

[0021] The positive electrode current collector foil 112 in each bipolar electrode 100 and the positive electrode current collector foil 112 in the positive electrode terminal electrode 200 have a positive electrode coating portion 112a and a non-coated positive electrode portion 112b.

[0022] The positive electrode coating portion 112a is a portion where the positive electrode active material layer 120 is provided. The positive electrode coating portion 112a is formed at the central portion of the positive electrode current collector foil 112.

[0023] The non-coated positive electrode portion 112b is a portion where the positive electrode active material layer 120 is not provided, that is, a portion where the positive electrode current collector foil 112 is exposed. The non-coated positive electrode portion 112b is formed around the positive electrode coating portion 112a (the peripheral edge portion of the positive electrode current collector foil 112).

[0024] Each bipolar electrode 100 and the negative electrode current collector foil 113 of the negative electrode terminal electrode 300 have a negative electrode coated portion 113a and a negative electrode uncoated portion 113b.

[0025] The negative electrode coating portion 113a is the area where the negative electrode active material layer 130 is provided. The negative electrode coating portion 113a is formed in the central part of the negative electrode current collector foil 113.

[0026] The uncoated negative electrode portion 113b is the portion where the negative electrode active material layer 130 is not provided, that is, the portion where the negative electrode current collector foil 113 is exposed. The uncoated negative electrode portion 113b is formed around the coated negative electrode portion 113a (the peripheral edge of the negative electrode current collector foil 113). In a pair of electrodes 100, 200, and 300 adjacent to each other in the stacking direction, the uncoated positive electrode portion 112b of one electrode and the uncoated negative electrode portion 113b of the other electrode are spaced apart and face each other in the stacking direction.

[0027] Each separator 400 is positioned between pairs of electrodes 100, 200, and 300 adjacent to each other in the stacking direction. Specifically, each separator 400 is positioned between the positive electrode active material layer 120 and the negative electrode active material layer 130. Each separator 400 is made of an insulating material and allows ion permeability. Examples of each separator 400 include polyolefin microporous membranes (such as a single-layer polyethylene structure or a three-layer structure of polypropylene, polyethylene, and polypropylene). A ceramic layer may be provided on at least one surface of the polyolefin microporous membrane.

[0028] The sealing member 20 is made of an insulating material (such as resin). The sealing member 20 holds the peripheral edges of each current collector foil 112, 113 and the peripheral edges of each separator 400. The sealing member 20 seals the space between pairs of electrodes 100, 200, and 300 that are adjacent to each other in the stacking direction within the electrode stack 10. More specifically, the sealing member 20 seals the space R (see Figure 1) formed between the uncoated positive electrode portion 112b of one electrode and the uncoated negative electrode portion 113b of the other electrode in a pair of electrodes 100, 200, and 300 that are adjacent to each other in the stacking direction, when the space R is at a pressure lower than atmospheric pressure. An electrolyte is sealed in the space R. The sealing member 20 has the function of preventing the leakage of electrolyte from the space R and the intrusion of moisture into the space R from the outside, as well as the function of ensuring the distance between the uncoated positive electrode portion 112b and the uncoated negative electrode portion 113b, which are arranged to sandwich the space R.

[0029] Because each space R is at a lower pressure than atmospheric pressure, as shown in Figure 1, the uncoated portion 112b of the positive electrode terminal electrode 200 and the uncoated portion 113b of the negative electrode terminal electrode 300 are deformed to be concave inward in the stacking direction. Space R functions as a gas pocket that contains the gas generated from each electrode 100, 200, and 300 during charging and discharging.

[0030] The liquid injection member 30 is a member for supplying electrolyte to the electrode stack 10 from outside the sealing member 20. The liquid injection member 30 is located inside the sealing member 20. The liquid injection member 30 communicates the space R with the outside of the sealing member 20. The liquid injection member 30 is made of, for example, resin (polyethylene, etc.). As shown in Figure 3, the liquid injection member 30 is formed in a rectangular tubular shape. However, the liquid injection member 30 is not limited to a rectangular tubular shape as long as it is cylindrical.

[0031] The liquid injection member 30 is used to reduce the pressure inside the sealing member 20. Therefore, the liquid injection member 30 has sufficient rigidity to prevent blockage during pressure reduction inside the sealing member 20. For example, the second moment of area of ​​the liquid injection member 30 is 3.8 mm. 4 It is preferable to set it to the above, 4.9 mm 4It is more preferable to set the values ​​to the above. For example, by setting the width wa (see Figure 3) of the liquid injection member 30 to 48.5 mm, the height ha (see Figure 3) to 1.0 mm, the opening width wb (see Figure 3) to 47.9 mm, and the opening height hb (see Figure 3) to 0.4 mm, the second moment of area is 3.8 mm. 4 Furthermore, by setting the width wa of the liquid injection member 30 to 48.5 mm, the height ha to 1.2 mm, the opening width wb to 48.1 mm, and the opening height hb to 0.8 mm, the second moment of area becomes 4.9 mm. 4 This is the result.

[0032] As shown in Figure 2, the liquid injection member 30 has an exposed end 32. The exposed end 32 is exposed to space R. The exposed end 32 has an inner end 32a formed on the inside in the stacking direction and an outer end 32b formed on the outside in the stacking direction. The outer end 32b is formed closer to the electrode stack 10 than the inner end 32a.

[0033] Next, a method for manufacturing the energy storage module 1 will be described. This manufacturing method includes a lamination process, a sealing process, an insulation inspection process, a liquid injection process, a charging process, and a reduced-pressure sealing process. This manufacturing method can be applied not only when manufacturing a single energy storage module 1, but also when manufacturing multiple energy storage modules together.

[0034] In the lamination process, multiple bipolar electrodes 100, positive terminal electrodes 200, and negative terminal electrodes 300 are laminated via separators 400. Specifically, multiple bipolar electrodes 100, positive terminal electrodes 200, and negative terminal electrodes 300 are laminated via separators 400 such that the uncoated positive portion 112b of one electrode and the uncoated negative portion 113b of the other electrode in pairs of electrodes 100, 200, and 300 adjacent to each other in the lamination direction face each other.

[0035] In the sealing process, the space R between the uncoated positive electrode portion 112b and the uncoated negative electrode portion 113b is sealed. Specifically, in the sealing process, the sealing member 20 is heat-welded to the peripheral edge of each electrode 100, 200, 300 in the electrode laminate 10 so as to form a sealing member 20 that seals the space R while holding a liquid injection member 30 that opens the space R between the uncoated positive electrode portion 112b and the uncoated negative electrode portion 113b to the outside.

[0036] The insulation inspection process is performed before the liquid injection process. In the insulation inspection process, a voltage is applied to the electrode laminate 10 while the pressure inside the sealing member 20 is reduced from the liquid injection member 30, so that the uncoated portion 112b of the positive electrode terminal electrode 200 is recessed inward in the stacking direction, and the uncoated portion 113b of the negative electrode terminal electrode 300 is recessed inward in the stacking direction. This inspects the insulation state between the uncoated portion 112b of the positive electrode terminal electrode 200 and the uncoated portion 113b of the negative electrode opposite to the uncoated portion 112b of the positive electrode terminal electrode 200, and the insulation state between the uncoated portion 113b of the negative electrode terminal electrode 300 and the uncoated portion 112b of the positive electrode opposite to the uncoated portion 113b of the negative electrode terminal electrode 300. The insulation inspection process is performed as follows.

[0037] In other words, after the liquid injection member 30 is temporarily sealed with the energy storage module 1 placed inside the depressurized chamber, the energy storage module 1 is opened to the atmosphere. As a result, the uncoated portion 112b of the positive electrode terminal electrode 200 and the uncoated portion 113b of the negative electrode terminal electrode 300 are recessed inward in the stacking direction. Then, a voltage is applied to the electrode stack 10.

[0038] Alternatively, when the energy storage module 1 is placed, for example, under atmospheric pressure, the pressure inside the sealing member 20 is reduced through the liquid injection member 30, and a voltage is applied to the electrode stack 10 in that state.

[0039] For example, if foreign matter such as a metal fragment is present between the uncoated positive electrode portion 112b of the positive electrode terminal electrode 200 and the uncoated negative electrode portion 113b facing the positive electrode portion 112b, and a short circuit occurs between the uncoated positive electrode portion 112b and the uncoated negative electrode portion 113b via this foreign matter, the short circuit will be detected when a voltage is applied to the electrode stack 10. On the other hand, if no short circuit occurs within the electrode stack 10, the insulation state is judged to be good.

[0040] The electrolyte injection process is performed after the insulation inspection process. In the electrolyte injection process, electrolyte is supplied into the sealing member 20 through each electrolyte injection member 30. The electrolyte injection process is performed under atmospheric pressure. In this process, the energy storage module 1 is placed under atmospheric pressure, so the uncoated portion 112b of the positive electrode termination electrode 200 and the uncoated portion 113b of the negative electrode termination electrode 300 return to a nearly flat state.

[0041] The charging process is performed after the electrolyte injection process. During the charging process, the energy storage module 1 is charged to a predetermined voltage. This causes the formation of an SEI film on the negative electrode through the decomposition of the electrolyte solvent and additives, and the by-product gas is discharged to the outside of the sealing member 20 through the electrolyte injection member 30.

[0042] In the post-charging depressurization sealing process, the liquid injection member 30 is sealed under a depressurized atmosphere (an atmosphere with a pressure lower than atmospheric pressure). This completes the energy storage module 1. When this energy storage module 1 is moved from a depressurized atmosphere to atmospheric pressure, as shown in Figure 1, the uncoated portion 112b of the positive electrode terminal electrode 200 and the uncoated portion 113b of the negative electrode terminal electrode 300 deform so as to be concave toward the inside in the stacking direction.

[0043] As described above, in the manufacturing method of the energy storage module 1 in this embodiment, since the insulation inspection step is performed before the liquid injection step, it is possible to inspect for the presence or absence of foreign matter that could cause a short circuit between the uncoated positive electrode portion 112b of the positive electrode terminal electrode 200 and the uncoated negative electrode portion 113b facing the uncoated positive electrode portion 112b, or between the uncoated negative electrode portion 113b of the negative electrode terminal electrode 300 and the uncoated positive electrode portion 112b facing the uncoated negative electrode portion 113b, before the liquid injection step and the charging step, that is, before voltage is generated in the electrode stack 10. Therefore, it is possible to safely perform insulation inspections while reducing the cycle time and power costs required for the manufacture of the energy storage module 1.

[0044] Furthermore, in the energy storage module 1 of this embodiment, since the liquid injection member 30 communicates the space R with the outside of the sealing member 20, when gas is generated from the electrode stack 10 due to an internal short circuit or the like in the electrode stack 10, the gas is discharged to the outside of the sealing member 20 through the liquid injection member 30. Thus, the direction of gas discharge is defined.

[0045] Those skilled in the art will understand that the exemplary embodiments and examples described above are specific examples of the following embodiments.

[0046] [Aspect 1] A method for manufacturing an energy storage module, comprising: an electrode stack including a plurality of bipolar electrodes stacked on top of each other; a positive terminal electrode disposed on one side of the plurality of bipolar electrodes in the stacking direction of the plurality of bipolar electrodes; a negative terminal electrode disposed on the other side of the plurality of bipolar electrodes in the stacking direction; a sealing member that seals the space between a pair of electrodes adjacent to each other in the stacking direction of the electrode stack; and a liquid injection member disposed within the sealing member for supplying an electrolyte to the electrode stack, wherein A lamination step of stacking the plurality of bipolar electrodes, the positive terminal electrode, and the negative terminal electrode such that the uncoated positive electrode portion of one electrode and the uncoated negative electrode portion of the other electrode in a pair of electrodes adjacent to each other in the lamination direction face each other. A sealing step in which a sealing member is formed on the peripheral edge of each electrode in the electrode laminate, such that the sealing member is formed to seal the space while holding the liquid injection member that opens the space between the uncoated portion of the positive electrode and the uncoated portion of the negative electrode to the outside, An insulation inspection step is performed by applying a voltage to the electrode stack while the pressure inside the sealing member is reduced from the liquid injection member, so that the uncoated portion of the positive electrode terminal electrode is recessed toward the inside in the stacking direction, and the uncoated portion of the negative electrode terminal electrode is recessed toward the inside in the stacking direction, thereby inspecting the insulation state between the uncoated portion of the positive electrode terminal electrode and the uncoated portion of the negative electrode facing the uncoated portion of the positive electrode terminal electrode, and the insulation state between the uncoated portion of the negative electrode terminal electrode and the uncoated portion of the positive electrode facing the uncoated portion of the negative electrode terminal electrode. After the insulation inspection step, an injection step is performed in which the electrolyte is supplied from the liquid injection member into the sealing member, A method for manufacturing an energy storage module, comprising a charging step for charging the electrode stack.

[0047] In this manufacturing method, since the insulation inspection process is performed before the liquid injection process, it becomes possible to inspect for the presence of foreign matter that could cause a short circuit between the uncoated positive electrode portion of the positive terminal electrode and the uncoated negative electrode portion facing the said uncoated positive electrode portion, or between the uncoated negative electrode portion of the negative terminal electrode and the uncoated positive electrode portion facing the said uncoated negative electrode portion, before the liquid injection process and the charging process, i.e., before voltage is generated in the electrode stack. Therefore, it becomes possible to safely perform insulation inspections while reducing the cycle time and power costs required for the manufacture of energy storage modules.

[0048] [Aspect 2] The liquid injection member has an exposed end that is exposed to the space, The exposed end is, The inner end formed on the inside in the stacking direction, Including an outer end formed on the outside in the stacking direction, The method for manufacturing an energy storage module according to embodiment 1, wherein the outer end is formed at a position closer to the electrode stack than the inner end.

[0049] In this embodiment, when the uncoated portion of the positive electrode terminal electrode and the uncoated portion of the negative electrode terminal electrode deform in a way that causes them to sink inward in the stacking direction during the insulation inspection process, the closure of the opening at the exposed end of the uncoated portion is suppressed.

[0050] [Aspect 3] An electrode laminate comprising a plurality of bipolar electrodes stacked on top of each other, a positive terminal electrode positioned on one side of the plurality of bipolar electrodes in the stacking direction of the plurality of bipolar electrodes, and a negative terminal electrode positioned on the other side of the plurality of bipolar electrodes in the stacking direction, A sealing member that seals between a pair of electrodes adjacent to each other in the stacking direction of the electrode stack, The sealing member is disposed within the sealing member and comprises an injection member for supplying an electrolyte to the electrode stack, Each of the aforementioned bipolar electrodes is A current collector including a positive electrode current collector foil and a negative electrode current collector foil, A positive electrode active material layer provided on the positive electrode current collector foil in the current collector, The current collector comprises a negative electrode active material layer provided on the negative electrode current collector foil, The positive terminal electrode is, Positive electrode current collector foil, The positive electrode current collector foil has a positive electrode active material layer provided on it, The aforementioned negative terminal electrode is, Negative electrode foil and The negative electrode foil has a negative electrode active material layer provided on it, The positive electrode current collector foil in each of the current collectors and the positive electrode current collector foil in the positive electrode terminal electrode are, The positive electrode coating portion provided with the positive electrode active material layer, The positive electrode has an uncoated portion where the positive electrode active material layer is not provided, The negative electrode current collector foil in each of the current collectors and the negative electrode current collector foil in the negative electrode terminal electrode are The negative electrode coating section provided with the negative electrode active material layer, It has a negative electrode uncoated portion that faces the positive electrode uncoated portion in the stacking direction and where the negative electrode active material layer is not provided, The sealing member seals the space formed between the uncoated positive electrode portion of one electrode and the uncoated negative electrode portion of the other electrode in the pair of electrodes adjacent to each other in the stacking direction, while the pressure of the space is lower than atmospheric pressure. The liquid injection member is a power storage module that connects the space with the outside of the sealing member.

[0051] In this energy storage module, the liquid injection member connects the space formed between the uncoated positive electrode portion of one electrode and the uncoated negative electrode portion of the other electrode in a pair of electrodes to the outside of the sealing member. Therefore, when gas is generated from the electrode stack due to an internal short circuit or the like in the electrode stack, that gas is discharged to the outside of the sealing member through the liquid injection member. Thus, the direction of gas discharge is defined.

[0052] [Aspect 4] The liquid injection member has an exposed end that is exposed to the space, The exposed end is, The inner end formed on the inside in the stacking direction, Including an outer end formed on the outside in the stacking direction, The energy storage module according to embodiment 3, wherein the outer end is formed closer to the electrode stack than the inner end.

[0053] In this embodiment, the uncoated portion of the positive electrode terminal electrode and the uncoated portion of the negative electrode terminal electrode are prevented from blocking the opening at their exposed ends.

[0054] It should be noted that the embodiments disclosed herein are illustrative in all respects and not restrictive. The scope of the present invention is indicated by the claims rather than the description of the embodiments above, and further includes all modifications within the meaning and scope equivalent to the claims. [Explanation of symbols]

[0055] 1 Energy storage module, 10 Electrode stack, 20 Sealing member, 30 Liquid injection member, 32 Exposed end, 32a Inner end, 32b Outer end, 100 Bipolar electrode, 110 Current collector, 112 Positive electrode current collector foil, 112a Positive electrode coated portion, 112b Positive electrode uncoated portion, 113 Negative electrode current collector foil, 113a Negative electrode coated portion, 113b Negative electrode uncoated portion, 120 Positive electrode active material layer, 130 Negative electrode active material layer, 200 Positive electrode termination electrode, 300 Negative electrode termination electrode, 400 Separator, R Space.

Claims

1. A lamination process in which multiple bipolar electrodes, a positive terminal electrode, and a negative terminal electrode are stacked, A sealing step in which a sealing member is formed on the peripheral edge of each electrode in an electrode stack such that a sealing member is formed that seals the space between the uncoated positive electrode portion and the uncoated negative electrode portion while holding a liquid injection member that opens the space to the outside, An insulation inspection step is performed by applying a voltage to the electrode laminate while the space is depressurized from the liquid injection member, thereby inspecting the insulation state between the uncoated portion of the positive electrode terminal electrode and the uncoated portion of the negative electrode facing the uncoated portion of the positive electrode, and the insulation state between the uncoated portion of the negative electrode terminal electrode and the uncoated portion of the positive electrode facing the uncoated portion of the negative electrode. After the insulation inspection step, an injection step is performed in which an electrolyte is supplied from the liquid injection member into the sealing member, A method for manufacturing an energy storage module, comprising a charging step for charging the electrode stack.

2. The liquid injection member has an exposed end that is exposed to the space, The exposed end is, The inner end formed on the inside in the stacking direction of the plurality of bipolar electrodes, Including an outer end formed on the outside in the stacking direction, The method for manufacturing an energy storage module according to claim 1, wherein the outer end is formed at a position closer to the electrode stack than the inner end.

3. An electrode laminate comprising multiple bipolar electrodes, a positive terminal electrode, and a negative terminal electrode, A sealing member that seals between a pair of adjacent electrodes in the electrode stack, The electrode stack comprises an injection member for supplying an electrolyte, Each of the bipolar electrodes is Current collector and, A positive electrode active material layer provided on the positive electrode current collector foil of the current collector, The current collector comprises a negative electrode active material layer provided on the negative electrode current collector foil, The positive terminal electrode is, Positive electrode current collector foil, The positive electrode current collector foil has a positive electrode active material layer provided on it, The aforementioned negative terminal electrode is, Negative electrode current collector foil, The negative electrode current collector foil has a negative electrode active material layer provided on it, Each of the positive electrode current collector foils has an uncoated portion of the positive electrode, Each of the aforementioned negative electrode current collector foils has an uncoated negative electrode portion. The sealing member seals the space between the uncoated portion of the positive electrode and the uncoated portion of the negative electrode when the pressure in that space is lower than atmospheric pressure. The liquid injection member is formed in a cylindrical shape that connects the space and the outside of the sealing member, and is sealed. The uncoated portion of the positive electrode terminal electrode and the uncoated portion of the negative electrode terminal electrode are recessed toward the inside in the stacking direction of the electrode laminate. The liquid injection member has an exposed end that is exposed to the space, The exposed end is, The inner end formed on the inside in the stacking direction, Including an outer end formed on the outside in the stacking direction, An energy storage module in which the outer end is formed closer to the electrode stack than the inner end.

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