Energy storage device and method for manufacturing an energy storage device

Abstract

In an energy storage device having a structure in which a plate-shaped battery and a plate-shaped member are bonded together with an adhesive, the quality of the energy storage device is improved. [Solution] The energy storage device 10 comprises a plate-shaped battery 12 and a plate-shaped member 14. The plate-shaped member 14 is positioned on one side of the plate-shaped battery 12 in the thickness direction, with its thickness direction oriented in the same direction as the thickness direction of the plate-shaped battery 12. The energy storage device 10 also has an adhesive 16 that is positioned between the plate-shaped battery 12 and the plate-shaped member 14. The adhesive 16 fixes the plate-shaped battery 12 and the plate-shaped member 14. The energy storage device 10 further comprises at least one adhesive member 18 positioned between the plate-shaped battery 12 and the plate-shaped member 14. The adhesive member 18 fixes the plate-shaped battery 12 and the plate-shaped member 14.

Description

Technical Field

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

Background Art

[0002] The power storage device disclosed in Patent Document 1 has a structure in which a bipolar battery module and an external current collector plate are adhered by an adhesive.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] An object of the present disclosure is to improve the quality of a power storage device having a structure in which a plate-shaped battery such as a bipolar battery module and a plate-shaped member such as an external current collector plate are adhered by an adhesive. Another object of the present disclosure is to improve the manufacturing efficiency in a method for manufacturing a power storage device having a structure in which a plate-shaped battery such as a bipolar battery module and a plate-shaped member such as an external current collector plate are adhered by an adhesive.

Means for Solving the Problems

[0005] (Power storage device) The power storage device according to the first aspect includes a plate-shaped battery, a plate-shaped member disposed on one side in the thickness direction of the plate-shaped battery with the thickness direction facing the same direction as the thickness direction of the plate-shaped battery, an adhesive disposed between the plate-shaped battery and the plate-shaped member to fix the plate-shaped battery and the plate-shaped member, and at least one adhesive member disposed between the plate-shaped battery and the plate-shaped member to fix the plate-shaped battery and the plate-shaped member.

[0006] In this embodiment, the energy storage device comprises a plate-shaped battery and a plate-shaped member. The plate-shaped member is positioned on one side of the plate-shaped battery in the thickness direction, with its thickness direction oriented in the same direction as the thickness direction of the plate-shaped battery. The energy storage device also includes an adhesive placed between the plate-shaped battery and the plate-shaped member. The adhesive fixes the plate-shaped battery and the plate-shaped member in place.

[0007] Incidentally, in energy storage devices having such a structure, it is desirable from a quality standpoint to properly control the thickness of the layer formed between the plate-shaped battery and the plate-shaped member (the layer on which the adhesive is placed, hereinafter sometimes referred to as the fixing layer). Therefore, in order to properly control the thickness, it is conceivable to perform a compression process when fixing with adhesive. This allows the adhesive to harden while the joint surface between the plate-shaped battery and the plate-shaped member is not perfectly flat but warped before fixing, with the warp corrected. However, it is not always easy to properly control the thickness with only a compression process. Therefore, in this embodiment, the energy storage device includes at least one adhesive member disposed between the plate-shaped battery and the plate-shaped member. The adhesive member fixes the plate-shaped battery and the plate-shaped member in place. Therefore, the quality of the energy storage device can be improved. This is because the adhesive material exerts the necessary adhesive strength to correct the warping of plate-shaped batteries and other components in a short compression time, making it easier to control the thickness of the layer formed between the plate-shaped battery and the plate-shaped component compared to energy storage devices that do not have such an adhesive material.

[0008] In the embodiments described later, the energy storage device is a large battery pack mounted under the vehicle floor, but the energy storage device in this embodiment is not limited to this. In the embodiments described later, the plate-shaped battery is a bipolar battery module, but this embodiment is not limited to this. The plate-shaped battery may be, for example, a monopolar battery cell. Furthermore, the plate-shaped battery may be a battery in which the thickness direction is the shortest side among the three sides extending in different directions of the plate-shaped battery. In other words, the direction of the shortest side among the three sides extending in different directions of the plate-shaped battery is the thickness direction of the plate-shaped battery. For example, the plate-shaped battery may be a so-called prismatic cell (a battery cell in which electrodes are housed in a metal can case). In the embodiments described later, the plate-shaped member is a current collector plate, a current-carrying plate, or a cooler, but the plate-shaped member in this embodiment is not limited to these. For example, the plate-shaped member may be other plate-shaped batteries. In the embodiments described later, the plate-shaped member functions to electrically connect one plate-shaped battery to another plate-shaped battery, but the plate-shaped member in this embodiment is not limited to this. In the embodiments described later, the adhesive is a conductive adhesive, but the adhesive in this embodiment is not limited to this. In the embodiments described later, the adhesive member is a double-sided adhesive tape, but the adhesive member in this embodiment is not limited to this. In the embodiments described later, the energy storage device has multiple fixed layers, and adhesive members are placed on all of these fixed layers, but this embodiment is not limited to this. The energy storage device in this embodiment does not have to have multiple fixed layers. Furthermore, even if the energy storage device has multiple fixed layers, it is not necessary for adhesive members to be placed on all of them. In the embodiments described later, the energy storage device is manufactured through a compression process, which is completed without waiting for the adhesive to harden. However, the energy storage device of this embodiment is not limited to this. For example, the compression process may be completed after the adhesive has hardened or is nearly hardened. Furthermore, the energy storage device of this embodiment is not limited to those manufactured by a specific manufacturing method.

[0009] In the second embodiment, the energy storage device, in the first embodiment, includes an adhesive member which is arranged along a first direction that is perpendicular to the thickness direction.

[0010] In this embodiment, at least one adhesive member includes an adhesive member that is arranged along a first direction which is perpendicular to the thickness direction. Therefore, the placement of adhesive members arranged along the first direction is simplified.

[0011] In the embodiments described later, the first direction coincides with the vehicle's longitudinal direction, but the first direction in this embodiment is not limited to this.

[0012] In the third embodiment, the energy storage device, in the first embodiment, includes a central region adhesive member which is arranged along a first direction perpendicular to the thickness direction and in the central 30% region of the plate-shaped battery in a second direction perpendicular to both the thickness direction and the first direction.

[0013] In this embodiment, at least one adhesive member includes a central region adhesive member. The central region adhesive member is an adhesive member that is positioned along a first direction which is perpendicular to the thickness direction, and is positioned in the central 30% region of the plate-shaped battery in a second direction which is perpendicular to both the thickness direction and the first direction. Therefore, at least one adhesive member can be used to make the adhesive members function more effectively compared to an embodiment that does not include a central region adhesive member. This is because, before the compression process, the plate-shaped battery and the plate-shaped member are often significantly separated in the central 30% region of the plate-shaped battery in the second direction.

[0014] In the fourth embodiment, the energy storage device, in the first embodiment, consists only of at least one central region adhesive member, which is arranged along a first direction perpendicular to the thickness direction and is located in the central 30% region of the plate-shaped battery in a second direction perpendicular to both the thickness direction and the first direction.

[0015] In this embodiment, at least one adhesive member is composed of at least one central region adhesive member. The central region adhesive member is an adhesive member that is positioned along a first direction which is perpendicular to the thickness direction, and is positioned in the central 30% region of the plate-shaped battery in a second direction which is perpendicular to both the thickness direction and the first direction. Therefore, the adhesive members can function more effectively compared to an embodiment in which at least one adhesive member does not include a central region adhesive member. In addition, the number of adhesive members can be reduced compared to an embodiment in which at least one adhesive member includes adhesive members other than the central region adhesive member.

[0016] In the fifth embodiment, the energy storage device, in the first embodiment, includes at least one adhesive member, which is arranged along a first direction perpendicular to the thickness direction and in the central 30% region of the plate-shaped battery in a second direction perpendicular to both the thickness direction and the first direction, and at least one outer region adhesive member, which is arranged along the first direction and in the region other than the central 30% region of the plate-shaped battery in the second direction, wherein the central region adhesive member has a larger arrangement area than the outer region adhesive member.

[0017] In this embodiment, at least one adhesive member includes at least one central region adhesive member and at least one outer region adhesive member. The central region adhesive member is an adhesive member arranged along a first direction and positioned in the central 30% region of the plate-shaped battery in a second direction, and the outer region adhesive member is an adhesive member arranged along the first direction and positioned in the region other than the central 30% region of the plate-shaped battery in a second direction. Moreover, the central region adhesive member has a larger area of placement than the outer region adhesive member. Therefore, the quality of the power storage device can be effectively improved with respect to the area of placement of the adhesive member.

[0018] In the power storage device according to the sixth aspect, in any of the first to fifth aspects, the adhesive has a larger area of placement than the at least one adhesive member.

[0019] Incidentally, usually, an adhesive can more easily secure the fixing strength between the plate-shaped battery and the plate-shaped member than an adhesive member. Therefore, in this aspect, the adhesive has a larger area of placement than the at least one adhesive member. Therefore, it is easy to secure the fixing strength between the plate-shaped battery and the plate-shaped member.

[0020] In the power storage device according to the seventh aspect, in any of the first to sixth aspects, the power storage device includes a wiring disposed between the plate-shaped battery and the plate-shaped member, and the at least one adhesive member includes an adjacent adhesive member adjacent to the wiring along the wiring, and no adhesive is disposed between the adjacent adhesive member and the wiring.

[0021] In this aspect, the power storage device includes a wiring disposed between the plate-shaped battery and the plate-shaped member. Incidentally, if an adhesive comes into contact with the wiring disposed between the plate-shaped battery and the plate-shaped member, there is a risk of problems. Examples of the problems include corrosion of the wiring due to the components of the adhesive. Therefore, in this aspect, the at least one adhesive member includes an adjacent adhesive member adjacent to the wiring along the wiring. And no adhesive is disposed between the adjacent adhesive member and the wiring. Therefore, while preventing the adhesive from coming into contact with the wiring, the adjacent adhesive member can secure the fixing strength between the plate-shaped battery and the plate-shaped member at the position adjacent to the wiring. This is because the adhesive has the property of spreading when crushed, while the adhesive member has a relatively weak property.

[0022] In the embodiments described later, the wiring is a thermistor that has the function of measuring temperature, but the wiring in this embodiment is not limited to this.

[0023] The energy storage device according to the eighth embodiment, in any of the first to sixth embodiments, comprises a wiring structure disposed between the plate-shaped battery and the plate-shaped member, wherein the at least one adhesive member includes a pair of adjacent adhesive members adjacent to the wiring structure so as to be along the wiring structure, the wiring structure is located between the pair of adjacent adhesive members, and no adhesive is disposed between the pair of adjacent adhesive members.

[0024] In this embodiment, the energy storage device includes wiring arranged between a plate-shaped battery and a plate-shaped member. Incidentally, if adhesive comes into contact with the wiring placed between the plate-shaped battery and the plate-shaped component, malfunctions may occur. These malfunctions could include, for example, corrosion of the wiring due to the components of the adhesive. Therefore, in this embodiment, at least one adhesive member includes a pair of adjacent adhesive members that are adjacent to the wiring and run along the wiring. The wiring is located between the pair of adjacent adhesive members, and no adhesive is placed between the pair of adjacent adhesive members. Therefore, while preventing the adhesive from coming into contact with the wiring, the pair of adjacent adhesive members ensure the fixing strength between the plate-shaped battery and the plate-shaped member at a position adjacent to the wiring.

[0025] In the ninth embodiment of the energy storage device, in the seventh or eighth embodiment, the wiring has a function for measuring temperature, and the adjacent adhesive member is a thermally conductive adhesive member.

[0026] In this embodiment, the wiring has a function for measuring temperature. Therefore, temperature information between the plate-shaped battery and the plate-shaped member can be obtained.

[0027] However, if the temperature rises locally near the wiring, it becomes impossible to obtain the desired temperature information. Therefore, one might consider placing a thermally conductive adhesive near the wiring to prevent localized temperature increases. However, if the adhesive comes into contact with the wiring, it may become impossible to measure the temperature accurately, and the wiring may corrode. Therefore, in this embodiment, the adjacent adhesive member is a thermally conductive adhesive member. Therefore, it is possible to suppress localized temperature increases near the wiring and prevent the aforementioned problems.

[0028] In the tenth embodiment of the energy storage device, in the ninth embodiment, the adhesive includes a thermally conductive adhesive, and the thermally conductive adhesive is adjacent to the adjacent adhesive member so as to be along the adjacent adhesive member.

[0029] In this embodiment, the adhesive includes a thermally conductive adhesive. The thermally conductive adhesive is adjacent to the adjacent adhesive member so as to be along the adjacent adhesive member. Therefore, it is possible to more effectively suppress localized temperature increases near wiring and prevent the aforementioned problems.

[0030] The energy storage device according to the 11th embodiment is a bipolar battery module in any of the 1st to 10th embodiments, comprising a plate-shaped battery comprising a bipolar electrode stack and a holder that holds the peripheral edge of the electrode stack.

[0031] In this embodiment, the plate-shaped battery is a bipolar battery module. The bipolar battery module comprises a bipolar electrode stack and a holder that holds the peripheral edge of the electrode stack. Therefore, the quality of an energy storage device in which bipolar battery modules and plate-shaped members are stacked can be improved.

[0032] In the twelfth embodiment of the energy storage device, in the eleventh embodiment, a plurality of plate-shaped batteries are provided, and one or more plate-shaped members are provided so as to be sandwiched between two adjacent plate-shaped batteries among the plurality of plate-shaped batteries, and two adjacent plate-shaped batteries among the plurality of plate-shaped batteries are electrically connected via the plate-shaped member sandwiched between the two plate-shaped batteries.

[0033] In this embodiment, multiple plate-shaped batteries are provided, and one or more plate-shaped members are provided so as to be sandwiched between two adjacent plate-shaped batteries. Two adjacent plate-shaped batteries are electrically connected via the plate-shaped member sandwiched between them. Therefore, from a quality standpoint, it is highly desirable that the thickness of the layer formed between the plate-shaped battery and the plate-shaped member (the layer on which the adhesive is placed) be properly controlled. In this regard, the energy storage device of this embodiment includes at least one adhesive member placed between the plate-shaped battery and the plate-shaped member, thus ensuring the quality of the energy storage device.

[0034] (Manufacturing method for energy storage devices) A method for manufacturing an energy storage device according to the 13th embodiment comprises: a plate-shaped battery; a plate-shaped member disposed on one side in the thickness direction of the plate-shaped battery with its thickness direction oriented in the same direction as the thickness direction of the plate-shaped battery; an adhesive disposed between the plate-shaped battery and the plate-shaped member to fix the plate-shaped battery and the plate-shaped member; and at least one adhesive member disposed between the plate-shaped battery and the plate-shaped member to fix the plate-shaped battery and the plate-shaped member, wherein the manufacturing method includes a compression step of applying a load to the plate-shaped battery and the plate-shaped member in their thickness direction while the adhesive and adhesive members are disposed between the plate-shaped battery and the plate-shaped member before curing.

[0035] In this embodiment, the manufacturing method includes a compression step. The compression step is a step of applying a compressive load to the plate-shaped battery and the plate-shaped member in the thickness direction, while the adhesive and adhesive member are placed between the plate-shaped battery and the plate-shaped member before curing. Therefore, compared to a manufacturing method that does not include a compression step, the thickness of the layer formed between the plate-shaped battery and the plate-shaped member (the layer on which the adhesive is placed) can be appropriately controlled. In the embodiments described later, the application of the load is terminated while the adhesive is still in an uncured state, but this embodiment is not limited to this.

[0036] In the 14th embodiment of the energy storage device, in the 13th embodiment, the time for applying the compressive load in the compression step is 30 minutes or less.

[0037] In this embodiment, the time for applying the compressive load in the compression process is 30 minutes or less (more preferably 1 minute or less, and even more preferably 30 seconds or less). Therefore, productivity can be improved compared to, for example, a configuration where the compression time is several hours. Furthermore, since the adhesive member exhibits the necessary adhesive strength for correcting warping of plate-shaped batteries, etc., even with a shorter compression time compared to adhesives, the application of load can be completed before the adhesive has cured. [Effects of the Invention]

[0038] As described above, according to this disclosure, the quality of an energy storage device can be improved in an energy storage device having a structure in which a plate-shaped battery and a plate-shaped member are bonded together with an adhesive. Furthermore, according to this disclosure, the manufacturing efficiency can be improved in a method for manufacturing an energy storage device having a structure in which a plate-shaped battery and a plate-shaped member are bonded together with an adhesive. [Brief explanation of the drawing]

[0039] [Figure 1] This is a schematic cross-sectional view showing the manufacturing process (lamination process) of the energy storage device according to this embodiment. [Figure 2] This is a schematic cross-sectional view showing the manufacturing process (compression process) of the energy storage device according to this embodiment. [Figure 3] This is a schematic cross-sectional view showing the energy storage device according to this embodiment. [Figure 4]This is a magnified cross-sectional view showing the fixing layer between the plate-shaped battery and the plate-shaped member. [Figure 5] This is a schematic cross-sectional view showing an enlarged view of a structure in which a temperature measuring device is provided between a plate-shaped battery and a plate-shaped member. [Figure 6] This is a schematic diagram showing a fixed layer, in which a temperature measuring device is provided between a plate-shaped battery and a plate-shaped member, as viewed from the stacking direction. [Figure 7] This is a schematic cross-sectional view of a bipolar battery module as a plate-shaped battery. [Figure 8] This is a cross-sectional view showing the structure of the adjacent adhesive member according to a modified example. [Modes for carrying out the invention]

[0040] The following describes the energy storage device 10 according to an embodiment.

[0041] As shown in Figure 3, the energy storage device 10 of this embodiment comprises a plurality of plate-shaped batteries 12 and a plurality of plate-shaped members 14.

[0042] The plate-shaped members 14 are arranged on one side and the other side of the plate-shaped battery 12 in the thickness direction, with their thickness direction facing the same direction as the thickness direction of the plate-shaped battery 12. As a result, the multiple plate-shaped batteries 12 and the multiple plate-shaped members 14 are arranged alternately along the stacking direction, with their thickness direction facing the stacking direction.

[0043] The multiple plate-shaped batteries 12 consist of a first plate-shaped battery 12A, a second plate-shaped battery 12B, a third plate-shaped battery 12C, and a fourth plate-shaped battery 12D. Unless otherwise specified, they are simply referred to as plate-shaped batteries 12.

[0044] As shown in Figure 4, adjacent plate-shaped batteries 12 and plate-shaped members 14 are fixed together by an adhesive 16 and an adhesive member 18. In other words, the energy storage device 10 comprises an adhesive 16 and an adhesive member 18.

[0045] The adhesive 16 is placed between the plate-shaped battery 12 and the plate-shaped member 14 to fix the plate-shaped battery 12 and the plate-shaped member 14. Multiple adhesive members 18 are placed between the plate-shaped battery 12 and the plate-shaped member 14 to fix the plate-shaped battery 12 and the plate-shaped member 14.

[0046] The adhesive 16 and adhesive member 18 are placed in all of the layers between the plate-shaped battery 12 and the plate-shaped member 14.

[0047] Adhesive 16 is a conductive adhesive. A conductive adhesive is an adhesive that has the property of conducting electricity and is a material used to ensure both mechanical and electrical connections simultaneously. A conductive adhesive comprises, for example, a base material made of resin (epoxy, acrylic, etc.) and conductive metal nanoparticles (silver, copper, carbon, etc.) dispersed within the base material.

[0048] The adhesive member 18 is specifically a double-sided adhesive tape 18. The double-sided adhesive tape 18 comprises a base material 18a and adhesive 18b provided on both sides of the base material 18a.

[0049] (Plate-shaped battery 12) Figure 7 is a schematic cross-sectional view of the plate-shaped battery 12 of this embodiment. As shown in Figure 7, the plate-shaped battery 12 of this embodiment is a bipolar battery module 12.

[0050] The bipolar battery module 12 comprises a bipolar electrode stack 30 and a frame-shaped holder 50 that holds the peripheral edge of the electrode stack 30.

[0051] The electrode stack 30 comprises a one-side electrode 34 on the side furthest in the stacking direction, a plurality of bipolar electrodes 32, a other-side electrode 36 on the other side furthest in the stacking direction, and a plurality of separators 38.

[0052] The one-sided electrode 34 comprises a current collector 42 and a positive electrode active material layer 44.

[0053] The bipolar electrode 32 comprises a negative electrode active material layer 46, a current collector 42, and a positive electrode active material layer 44.

[0054] The other electrode 36 comprises a negative electrode active material layer 46 and a current collector 42.

[0055] The separator 38 is placed between adjacent electrodes in the stacking direction.

[0056] The holder 50 is made of synthetic resin. The holder 50 holds a plurality of current collectors 42 and a plurality of separators 38. The method of forming the holder 50 is not particularly limited.

[0057] In the bipolar battery module 12, the portion S enclosed by the dotted line in the diagram can be considered as one cell. The number of cells in the bipolar battery module 12 is, for example, 25 to 34. Electrolyte is injected into each cell.

[0058] Each plate-shaped member 14 electrically connects the current collector 42 on the furthest side in the stacking direction of the bipolar battery module 12 to the current collector 42 on the furthest side in the stacking direction of another bipolar battery module 12 adjacent to the said bipolar battery module 12 on the furthest side in the stacking direction, via an adhesive 16 or the like.

[0059] (Plate-shaped member 14) As shown in Figure 3, the multiple plate-shaped members 14 include a pair of current collector plates 22A and 22B, a cooler 24, and a current-carrying plate 26. Specifically, the multiple plate-shaped members 14 consist of a pair of current collector plates 22A and 22B, two coolers 24, and one current-carrying plate 26.

[0060] The pair of current collector plates 22A and 22B are components for extracting electricity from the energy storage device 10. The pair of current collector plates 22A and 22B are arranged on one side and the other side in the stacking direction for a plurality (four) of plate-shaped batteries 12.

[0061] The cooler 24 is made of metal. The cooler 24 electrically connects two plate-shaped batteries 12 that are adjacent to each other in the stacking direction, with the cooler 24 in between, and functions to cool the two plate-shaped batteries 12. Specifically, the two coolers consist of a first cooler 24A that electrically connects the first plate-shaped battery 12A and the second plate-shaped battery 12B, and a second cooler 24B that electrically connects the third plate-shaped battery 12C and the fourth plate-shaped battery 12D.

[0062] As shown in Figure 1, the cooler 24 has refrigerant passages 25 inside. Multiple refrigerant passages 25 are formed, extending in a first direction and aligned in a second direction.

[0063] The conductive plate 26 is made of metal. The conductive plate 26 functions to electrically connect two adjacent plate-shaped batteries 12 in the stacking direction. Specifically, the conductive plate 26 electrically connects the second plate-shaped battery 12B and the third plate-shaped battery 12C.

[0064] Furthermore, the energy storage device 10 includes a first insulating sheet 19A and a second insulating sheet 19B. The first insulating sheet 19A is positioned outward in the stacking direction relative to the first current collector plate 22A, and the second insulating sheet 19B is positioned outward in the stacking direction relative to the second current collector plate 22B. Each insulating sheet 19A and 19B is fixed to each current collector plate 22A and 22B with an adhesive. This adhesive is a structural adhesive and is a different type of adhesive from the adhesive 16 (conductive adhesive) described above.

[0065] Furthermore, the energy storage device 10 includes a case 60 that houses a plurality of plate-shaped batteries 12 and a plurality of plate-shaped members 14. The case 60 comprises a lower case 62 and an upper case 64.

[0066] The energy storage device 10 is a battery pack mounted under the floor of the vehicle. When the energy storage device 10 is mounted under the floor of the vehicle, the first direction coincides with the vehicle's longitudinal direction, and the second direction coincides with the vehicle's width direction. The center position in the second direction of the energy storage device 10 coincides with the center position in the vehicle's width direction.

[0067] The energy storage device 10 may also include a temperature measuring device 70 for acquiring temperature information between the plate-shaped battery 12 and the plate-shaped member 14. Figure 5 is a schematic cross-sectional view showing an enlarged view of a structure in which the temperature measuring device 70 is provided between the plate-shaped battery 12 and the plate-shaped member 14. Figure 6 is a schematic view of the above structure (fixed layer) as seen from the stacking direction.

[0068] The temperature measuring device 70 is a linearly extending device comprising a thermistor, which is a temperature measuring unit, and an FPC connected to the thermistor. The temperature measuring device 70 is positioned between the plate-shaped battery 12 and the plate-shaped member 14. More specifically, the temperature measuring device 70 is positioned between the plate-shaped battery 12 and the plate-shaped member 14 so as to extend linearly parallel to the first direction. Hereinafter, the temperature measuring device 70 may be referred to as the wiring 70.

[0069] In the example shown in Figure 6, three temperature measuring devices 70 are provided in the fixed layer between the plate-shaped battery 12 and the plate-shaped member 14. Each temperature measuring device 70 extends linearly parallel to the first direction. A pair of adjacent adhesive members 18 are provided corresponding to one temperature measuring device 70. The pair of adjacent adhesive members 18 are adjacent to the temperature measuring device 70 so as to be along the temperature measuring device 70. The temperature measuring device 70 is located between the pair of adjacent adhesive members 18, and no adhesive 16 is placed between the pair of adjacent adhesive members 18.

[0070] The adjacent adhesive member 18 is a thermally conductive adhesive member 18, specifically a thermally conductive adhesive tape. A thermally conductive adhesive tape means an adhesive tape that has the property of efficiently transferring heat. The thermally conductive adhesive tape 18 of this embodiment comprises a base material with excellent thermal conductivity and a thermally conductive adhesive provided on both sides of the base material. The thermally conductive adhesive 18b comprises, for example, an acrylic-based or silicone-based adhesive and a thermally conductive filler (for example, fine particles such as aluminum oxide, magnesium oxide, or aluminum nitride) mixed in the adhesive.

[0071] (Manufacturing method) The manufacturing method for the energy storage device 10 of this embodiment includes the following steps in order. (1) Preparation process for preparing each layer (2) Arrangement step of arranging the adhesive 16 and adhesive member 18 (3) Lamination process for stacking each laminate (4) Compression process in which a compressive load is applied in the stacking direction to the laminate formed by stacking each laminate.

[0072] In the preparation process, each laminate is prepared. The laminates include the insulating sheets 19A and 19B, current collector plates 22A and 22B, bipolar battery module 12, cooler 24, and current collector plates 22A and 22B as described above.

[0073] In the placement process, the adhesive 16 and the adhesive member 18 are placed. As shown in Figure 1, the adhesive 16 is positioned to extend in the first direction at multiple different locations in the second direction. Specifically, the adhesive 16 is applied in a bead-like manner (for example, a bead with a diameter of 2-4 mm) so as to extend in the first direction at multiple different locations in the second direction. The adhesive members 18 are arranged at multiple different positions in the second direction, extending in the first direction. Preferably, the positions where the adhesive members 18 are placed are those that do not come into contact with the adhesive 16. Positions where the adhesive 16 does not come into contact with the adhesive 16 mean positions where it does not come into contact even after the adhesive 16 has spread in the second direction due to the compression process. The adhesive 16 and the adhesive member 18 are placed on the lower surface in the direction of gravity of the pair of surfaces to be bonded.

[0074] In the lamination process, each laminate is stacked as shown in Figure 1.

[0075] The compression process is carried out with each stack placed on the equipment-side base plate 90, as shown in Figure 2.

[0076] The duration for which the compressive load is continuously applied during the compression process (compression time) is, for example, 10 seconds. However, the compression time is not limited to this. From the viewpoint of manufacturing efficiency, the compression time is preferably 30 minutes or less, more preferably 1 minute or less, and even more preferably 30 seconds or less.

[0077] As shown in Figure 1, the compression process is carried out with the laminate housed in the lower case 62. In other words, the lower case 62 is also included in the objects to be compressed. In addition to the objects described above, the objects to be compressed may also include, for example, a shear panel assembly (not shown). A shear panel assembly is a panel-shaped component that protects the energy storage device 10, which is a battery pack, from objects that have fallen on the road, etc.

[0078] <Effects and Effects> Next, the effects and advantages of this embodiment will be described.

[0079] In this embodiment, as shown in Figure 3, the energy storage device 10 comprises a plate-shaped battery 12 and a plate-shaped member 14. The plate-shaped member 14 is positioned on one side of the plate-shaped battery 12 in the thickness direction, with its thickness direction oriented in the same direction as the thickness direction of the plate-shaped battery 12. Furthermore, as shown in Figure 4, the energy storage device 10 has an adhesive 16 that is placed between the plate-shaped battery 12 and the plate-shaped member 14. The adhesive 16 fixes the plate-shaped battery 12 and the plate-shaped member 14.

[0080] Incidentally, in an energy storage device 10 having such a structure, it is preferable from a quality standpoint to appropriately control the thickness of the layer formed between the plate-shaped battery 12 and the plate-shaped member 14 (the layer on which the adhesive 16 is placed, the fixing layer). Therefore, in order to appropriately control the thickness, it is conceivable to perform a compression process when fixing with the adhesive 16. This allows the adhesive 16 to harden while the joint surface between the plate-shaped battery 12 and the plate-shaped member 14 is not perfectly flat but has a warp before fixing. However, it is not always easy to appropriately control the thickness with only a compression process. Therefore, in this embodiment, as shown in Figure 4, the energy storage device 10 includes at least one adhesive member 18 positioned between the plate-shaped battery 12 and the plate-shaped member 14. The adhesive member 18 fixes the plate-shaped battery 12 and the plate-shaped member 14. Therefore, the quality of the energy storage device 10 can be improved. This is because the adhesive member 18 exerts the adhesive force necessary to correct the warping of the plate-shaped battery 12, etc., in a short compression time, making it easier to control the thickness of the layer formed between the plate-shaped battery 12 and the plate-shaped member 14 compared to an energy storage device that does not have such an adhesive member 18.

[0081] Furthermore, in this embodiment, as shown in Figure 4, at least one adhesive member 18 includes an adhesive member 18 that is arranged along a first direction which is perpendicular to the thickness direction. Therefore, the placement of the adhesive members 18, which are arranged along the first direction, is simplified.

[0082] Furthermore, in the example shown in Figure 1 or Figure 6, at least one adhesive member 18 includes a central region adhesive member 18C. The central region adhesive member 18C is an adhesive member 18 that is positioned along a first direction and also positioned in the central 30% region of the plate-shaped battery 12 in a second direction. Therefore, the adhesive members 18 can function more effectively compared to an embodiment in which at least one adhesive member 18 does not include the central region adhesive member 18C. This is because, before the compression process, the plate-shaped battery 12 and the plate-shaped member 14 are often significantly separated in the central 30% region of the plate-shaped battery 12 in the second direction. In this embodiment, the plate-shaped battery 12, plate-shaped member 14, etc., have an upward convex curve when viewed in the first direction (see Figure 1) due to structural considerations in the state before the compression process.

[0083] Furthermore, in the example shown in Figure 1, at least one adhesive member 18 is composed of only at least one central region adhesive member 18C. The central region adhesive member 18C is an adhesive member 18 that is positioned along the first direction and also positioned in the central 30% region of the plate-shaped battery 12 in the second direction. Therefore, the adhesive members 18 can function more effectively compared to an embodiment in which at least one adhesive member 18 does not include the central region adhesive member 18C. In addition, the number of adhesive members 18 can be reduced compared to an embodiment in which at least one adhesive member 18 includes adhesive members 18 other than the central region adhesive member 18C.

[0084] Furthermore, in the example shown in Figure 6, at least one adhesive member 18 includes at least one central region adhesive member 18C and at least one outer region adhesive member 18S. The central region adhesive member 18C is an adhesive member 18 that is arranged along the first direction and is positioned in the central 30% region of the plate-shaped battery 12 in the second direction, and the outer region adhesive member 18S is an adhesive member 18 that is arranged along the first direction and is positioned in the region other than the central 30% region of the plate-shaped battery 12 in the second direction. Although not shown in the diagram, the central adhesive member 18C may have a larger placement area (total placement area) than the outer adhesive member 18S. In this case, the quality of the energy storage device 10 can be effectively improved in relation to the area of ​​the adhesive member 18.

[0085] Incidentally, adhesive 16 is generally more effective than adhesive material 18 in ensuring sufficient fixing strength between the plate-shaped battery 12 and the plate-shaped member 14. Therefore, in this embodiment, as shown in Figure 6, the adhesive 16 may have a larger placement area (total placement area) than at least one adhesive member 18. In this case, it is easier to ensure the fixing strength between the plate-shaped battery 12 and the plate-shaped member 14.

[0086] Furthermore, in the examples shown in Figures 5 and 6, the energy storage device 10 includes wiring 70 arranged between the plate-shaped battery 12 and the plate-shaped member 14. By the way, if the adhesive 16 comes into contact with the wiring 70 placed between the plate-shaped battery 12 and the plate-shaped member 14, malfunctions may occur. For example, malfunctions such as corrosion of the wiring 70 due to the components of the adhesive 16 may occur. Therefore, in this embodiment, at least one adhesive member 18 includes an adjacent adhesive member 18 that is adjacent to the wiring 70 so as to follow the wiring 70. And, no adhesive 16 is placed between the adjacent adhesive member 18 and the wiring 70. Therefore, while preventing the adhesive 16 from coming into contact with the wiring 70, the adjacent adhesive member 18 ensures the fixing strength between the plate-shaped battery 12 and the plate-shaped member 14 at a position adjacent to the wiring 70. This is because the adhesive 16 has a property of being crushed and spreading, whereas the adhesive member 18 has a relatively weaker property in this regard.

[0087] Furthermore, in the examples shown in Figures 5 and 6, at least one adhesive member 18 includes a pair of adjacent adhesive members 18 that are adjacent to the wiring 70 and run along the wiring 70. The wiring 70 is located between the pair of adjacent adhesive members 18, and no adhesive 16 is placed between the pair of adjacent adhesive members 18. Therefore, while preventing the adhesive 16 from coming into contact with the wiring 70, the pair of adjacent adhesive members 18 can ensure the fixing strength between the plate-shaped battery 12 and the plate-shaped member 14 at a position adjacent to the wiring 70.

[0088] Furthermore, in the examples shown in Figures 5 and 6, the wiring 70 has a function for measuring temperature. Therefore, temperature information between the plate-shaped battery 12 and the plate-shaped member 14 can be obtained.

[0089] However, if the temperature rises locally near the wiring 70, it becomes impossible to obtain the desired temperature information. Therefore, to prevent localized temperature increases, it is conceivable to place a thermally conductive adhesive near the wiring 70. However, if the adhesive comes into contact with the wiring 70, it may become impossible to accurately measure the temperature, and the wiring 70 may corrode. Therefore, in the examples shown in Figures 5 and 6, the adjacent adhesive member 18 is a thermally conductive adhesive member 18. Therefore, localized temperature increases near the wiring 70 can be suppressed, preventing the aforementioned problems.

[0090] Furthermore, in this embodiment, the adhesive 16 may include a thermally conductive adhesive 16. It is preferable that the thermally conductive adhesive 16 be arranged so as to be adjacent to the adjacent adhesive member 18 along the adjacent adhesive member 18. For example, among the multiple adhesives 16 arranged in the second direction, only the adhesive 16 adjacent to the adjacent adhesive member 18 may be a thermally conductive adhesive. In this case, the localized temperature rise near the wiring 70 can be more effectively suppressed, preventing the aforementioned problems.

[0091] Furthermore, in this embodiment, as shown in Figure 7, the plate-shaped battery 12 is a bipolar battery module 12. The bipolar battery module 12 comprises a bipolar electrode stack 30 and a holder 50 that holds the peripheral edge of the electrode stack 30. Therefore, the quality of the energy storage device 10, in which the bipolar battery module 12 and the plate-shaped member 14 are stacked, can be improved.

[0092] Furthermore, in this embodiment, as shown in Figure 3, multiple plate-shaped batteries 12 are provided, and one or more plate-shaped members 14 are provided so as to be sandwiched between two adjacent plate-shaped batteries 12. Then, two adjacent plate-shaped batteries 12 are electrically connected via the plate-shaped member 14 sandwiched between them. Therefore, from a quality standpoint, it is highly desirable that the thickness of the layer formed between the plate-shaped battery 12 and the plate-shaped member 14 (the layer on which the adhesive 16 is placed) be properly controlled. In this regard, the energy storage device of this embodiment includes at least one adhesive member 18 placed between the plate-shaped battery 12 and the plate-shaped member 14, so that the quality of the energy storage device 10 can be ensured.

[0093] (Manufacturing method for energy storage devices) Furthermore, in this embodiment, the manufacturing method includes a compression step (see Figure 2). The compression step is a process in which, with the uncured adhesive 16 and adhesive member 18 placed between the plate-shaped battery 12 and the plate-shaped member 14, a compressive load is applied to the plate-shaped battery 12 and the plate-shaped member 14 in the thickness direction. Therefore, compared to a manufacturing method that does not include a compression step, the thickness of the layer formed between the plate-shaped battery 12 and the plate-shaped member 14 (the layer on which the adhesive 16 is placed) can be appropriately controlled.

[0094] Furthermore, in this embodiment, the time for applying the compressive load in the compression process is 30 minutes or less (more preferably 1 minute or less, and even more preferably 30 seconds or less). Therefore, productivity can be improved compared to, for example, an embodiment where the compression time is several hours. Furthermore, since the adhesive member 18 exhibits the necessary adhesive strength for correcting warping of the plate-shaped battery 12, etc., even with a shorter compression time compared to the adhesive 16, the application of load can be completed before the adhesive has cured.

[0095] <Modified form of the first embodiment> Figure 8 is a schematic cross-sectional view showing an adjacent adhesive member 18B according to a modified example.

[0096] The adjacent adhesive member 18B comprises a proximity portion 18B1 that is close to the temperature measuring device 70 and a general portion 18B2 that is farther from the temperature measuring device 70. The proximity portion 18B1 has a greater thickness than the general portion 18B2. As a result, the proximity portion 18B1 is in contact with both the plate-shaped battery 12 and the plate-shaped member 14, while the general portion 18B2 is in contact with only one of the plate-shaped battery 12 or the plate-shaped member 14. Therefore, a gap is formed between the general portion 18B2 and the other of the plate-shaped battery 12 or the plate-shaped member 14.

[0097] The gap described above is designed to allow adhesive 16 to enter. This adhesive 16 is a thermally conductive adhesive. This prevents the adhesive 16 from entering the temperature measuring device 70 while improving thermal conductivity (cooling performance). This is because, generally, it is easier to obtain thermally conductive adhesives that have higher thermal conductivity than thermally conductive adhesive materials.

[0098] Furthermore, the means by which the adjacent portion 18B1 and the general portion 18B2 of the adjacent adhesive member 18B are made to have the structure described above are not particularly limited. For example, as shown in Figure 8, two double-sided adhesive tapes can be layered in the portion close to the temperature measuring device 70.

[0099] While preferred embodiments of the present disclosure have been described above, the present disclosure is not limited to these descriptions. [Explanation of symbols]

[0100] 10 Energy storage device 12. Bipolar battery module (plate-type battery) 14 Plate-shaped member 16 Adhesive 18. Double-sided adhesive tape (adhesive material) 18C Central region adhesive member 18S outer area adhesive material 18 Adjacent adhesive members 18B1 Proximity Section 18B Adjacent adhesive member 18B2 General 18a Base material 18b Adhesive 19A, 19B Insulating Sheet 19A Each insulating sheet 19A First Insulating Sheet 19B Second insulating sheet 22A, 22B Current collector plate 24 Second cooler 24 Cooler 26 Current carrying board 30 Electrode Stack 32 bipolar electrodes 34 One-sided electrode 36 Other side electrode 38 Separator 42 Current collector 44 Positive electrode active material layer 46 Negative electrode active material layer 50 Holder 60 cases 62 Lower Cases 64 Upper Case 70 Temperature measuring device (wiring)

Claims

1. Plate-shaped battery and, A plate-shaped member is positioned on one side of the plate-shaped battery in the thickness direction, with its thickness direction oriented in the same direction as the thickness direction of the plate-shaped battery. An adhesive is placed between the plate-shaped battery and the plate-shaped member to fix the plate-shaped battery and the plate-shaped member together. At least one adhesive member is disposed between the plate-shaped battery and the plate-shaped member to fix the plate-shaped battery and the plate-shaped member, A power storage device equipped with the following features.

2. The at least one adhesive member is Adhesive member arranged along the first direction, which is perpendicular to the thickness direction. including, The energy storage device according to claim 1.

3. The at least one adhesive member is A central region adhesive member is positioned along a first direction perpendicular to the thickness direction and in the central 30% region of the plate-shaped battery in a second direction perpendicular to both the thickness direction and the first direction. including, The energy storage device according to claim 1.

4. The at least one adhesive member is At least one central region adhesive member is positioned along a first direction which is perpendicular to the thickness direction, and is positioned in the central 30% region of the plate-shaped battery in a second direction which is perpendicular to both the thickness direction and the first direction. It consists only of, The energy storage device according to claim 1.

5. The at least one adhesive member is At least one central region adhesive member is arranged along a first direction which is perpendicular to the thickness direction, and is positioned in the central 30% region of the plate-shaped battery in a second direction which is perpendicular to both the thickness direction and the first direction, An outer region adhesive member is arranged along the first direction and in a region other than the central 30% region of the plate-shaped battery in the second direction, Includes, The central region adhesive member has a larger placement area than the outer region adhesive member. The energy storage device according to claim 1.

6. The adhesive has a larger placement area than the at least one adhesive member. The energy storage device according to claim 1.

7. The aforementioned energy storage device is Wiring arranged between the plate-shaped battery and the plate-shaped member Equipped with, The at least one adhesive member includes an adjacent adhesive member that is adjacent to the wiring along the wiring, No adhesive is placed between the adjacent adhesive member and the wiring. The energy storage device according to claim 1.

8. The aforementioned energy storage device is Wiring arranged between the plate-shaped battery and the plate-shaped member Equipped with, The at least one adhesive member is A pair of adjacent adhesive members that are adjacent to the wiring so as to run along the wiring. Includes, The wiring is located between the pair of adjacent adhesive members. No adhesive is placed between the pair of adjacent adhesive members. The energy storage device according to claim 1.

9. The aforementioned wiring has a function for measuring temperature, The adjacent adhesive member is a thermally conductive adhesive member. The energy storage device according to claim 7 or claim 8.

10. The aforementioned adhesive includes a thermally conductive adhesive. The thermally conductive adhesive is located adjacent to the adjacent adhesive member, along the adjacent adhesive member. The energy storage device according to claim 9.

11. The aforementioned plate-shaped battery is A bipolar electrode stack, A holder that holds the peripheral edge of the electrode stack, This is a bipolar battery module equipped with the following features: The energy storage device according to claim 1.

12. Multiple plate-shaped batteries are provided, The plate-shaped members are provided one or more times so as to be sandwiched between two adjacent plate-shaped batteries among the plurality of plate-shaped batteries. Two adjacent plate-shaped batteries among the plurality of plate-shaped batteries are electrically connected via the plate-shaped member sandwiched between the two plate-shaped batteries. The energy storage device according to claim 11.

13. Plate-shaped battery and, A plate-shaped member is positioned on one side of the plate-shaped battery in the thickness direction, with its thickness direction oriented in the same direction as the thickness direction of the plate-shaped battery. An adhesive is placed between the plate-shaped battery and the plate-shaped member to fix the plate-shaped battery and the plate-shaped member together. At least one adhesive member is disposed between the plate-shaped battery and the plate-shaped member to fix the plate-shaped battery and the plate-shaped member, A method for manufacturing an energy storage device comprising: The aforementioned manufacturing method is Compression process: With the uncured adhesive and adhesive member placed between the plate-shaped battery and the plate-shaped member, a compressive load is applied to the plate-shaped battery and the plate-shaped member in the thickness direction. including, A method for manufacturing an energy storage device.

14. The time for applying the compressive load in the aforementioned compression process is 30 minutes or less. A method for manufacturing an energy storage device according to claim 13.

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