Battery pack

Abstract

The utility model relates to a battery pack, its inside space contains battery module, the battery module is stacked by electrode laminated body and cooler across temperature sensor, electrode laminated body and cooler are bonded through the bonding body, the bonding body is the sheet material with the adhesion on both sides. Adopt the utility model, can prevent the adhesive to enter the part with temperature sensor.

Description

Technical Field

[0001] This utility model relates to a battery pack. Background Technology

[0002] Japanese Patent Application Publication No. 2022-168593 discloses a battery pack in which a spacer is provided between a first battery module and a second battery module, and a temperature sensor for measuring the temperature of the first battery module and the second battery module is provided on the spacer.

[0003] The battery pack disclosed in Japanese Patent Application Publication No. 2022-168593 has only the outer periphery of the battery modules bonded with sealing resin, resulting in weak adhesive force to fix the battery modules together. However, when liquid adhesives are used to more firmly fix the battery modules, there is a technical problem that the adhesive may enter the areas where temperature sensors and flexible printed circuit boards (FPCs) are located, making it difficult to perform accurate temperature detection. Utility Model Content

[0004] This invention addresses the aforementioned technical problems by providing a battery pack that prevents adhesive from entering the area where a temperature sensor is located.

[0005] The battery pack of this utility model houses a battery module in its internal space. The battery module is composed of an electrode stack and a cooler stacked together with a temperature sensor in between. The electrode stack and the cooler are bonded together by an adhesive, which is a sheet material with adhesive properties on both sides.

[0006] The adhesive can be disposed on the periphery of the temperature sensor. The bonding surface of the electrode stack and the cooler are bonded to each other at the periphery by the adhesive. The parts outside the periphery can be bonded by an adhesive layer, which is formed by curing a liquid adhesive.

[0007] The end face of the adhesive may be formed with steps or inclinations to increase the surface area of ​​the end face.

[0008] According to this invention, a battery pack can be provided that can prevent adhesive from entering the part where a temperature sensor is located. Attached Figure Description

[0009] Figure 1A This is a schematic perspective view of the battery module involved in the embodiment of this utility model.

[0010] Figure 1B This is a schematic perspective view of the battery pack involved in the embodiment of this utility model.

[0011] Figure 2This is an xy cross-sectional view of the battery module involved in the embodiment of this utility model.

[0012] Figure 3 This is a YZ cross-sectional view of the battery module involved in the embodiment of this utility model.

[0013] Figure 4A This is a YZ cross-sectional view of the battery module involved in the embodiment of this utility model.

[0014] Figure 4B The YZ cross-sectional view shows the case where the end face shape of the adhesive body of the battery module involved in the embodiment of this utility model has been changed.

[0015] Figure 4C A yz cross-sectional view showing the case where the end face shape of the adhesive body of the battery module involved in the embodiment of this utility model has been changed.

[0016] Figure 5 This is a flowchart illustrating a method for manufacturing a battery pack according to an embodiment of the present invention. Detailed Implementation

[0017] The specific embodiments of this utility model are described in detail below with reference to the accompanying drawings. However, this utility model is not limited to the following embodiments. In addition, for clarity of explanation, the following description and drawings have been appropriately simplified.

[0018] Figure 1A This is a schematic perspective view of the battery module involved in the embodiment of this utility model. Figure 1B This is a schematic perspective view of the battery pack according to an embodiment of the present invention. Additionally, Figure 1A and Figure 1B The right-handed xyz orthogonal coordinate system shown is used for convenience to represent the positional relationships of constituent elements. The positive z-axis is vertically upward, and the xy plane is horizontal. Figures 1A to 4C The attached figures are identical.

[0019] Battery module 10 includes electrode stack 11 and cooler 12. One or more stacked electrodes are also possible. Figure 1A The battery module 10 shown is housed within the internal space of the outer casing 13, constituting Figure 1B Battery pack 1 is shown.

[0020] In addition, although Figure 1BThe internal space of the outer casing 13 houses two battery modules 10, but the size, number, and configuration of the battery modules 10 can be appropriately determined according to the size and purpose of the battery pack 1. In addition, in order for the battery pack 1 to function as a battery, the internal space of the outer casing 13 may also house, in addition to the battery modules 10, a power board, current collector, or insulating sheet, etc.

[0021] As will be described later Figure 3 As shown, the electrode stack 11 is stacked with the cooler 12 through the temperature sensor 121 and the flexible printed circuit board 122. For example, in the case of a lithium-ion secondary battery, the electrode stack 11 has a structure in which a positive electrode containing lithium cobalt oxide, lithium nickel oxide, or lithium manganese oxide is stacked with a negative electrode containing carbon, graphite, or lithium titanate through a separator. However, the battery type of the battery pack 1 can also be a nickel-metal hydride battery, a lead-acid battery, or an all-solid-state battery, or other types of batteries. In addition, multiple positive and negative electrodes can be stacked in the electrode stack 11, and the positive and negative electrodes can arbitrarily contain electrolytes, conductive additives, and binders. Furthermore, an electrolyte for enabling the electrode stack 11 to function as a battery can also be contained inside the electrode stack 11.

[0022] Cooler 12 cools electrode stack 11. Cooler 12 has, for example, piping through which refrigerants such as air, water, and coolant flow.

[0023] The outer casing 13 internally houses the electrode laminate 11 and the cooler 12. The outer casing 13 is, for example, made of a metal can or a laminated film made by bonding metal foil with a resin such as polypropylene.

[0024] Figure 2 The image shows the xy-section of the battery module involved in the embodiment of this utility model, which is the xy-section of the upper part of the cooler 12. Figure 3 This is a YZ cross-sectional view of the battery module involved in the embodiment of this utility model.

[0025] Temperature sensor 121 is located between electrode stack 11 and cooler 12 to measure the temperature of electrode stack 11. Temperature sensor 121 is, for example, a negative temperature coefficient thermistor (NTC thermistor) of semiconductor ceramic containing oxides such as nickel, manganese, and iron.

[0026] The flexible printed circuit board 122 has circuitry that can be connected to the temperature sensor 121. The flexible printed circuit board 122 transmits the temperature information of the electrode stack 11 measured by the temperature sensor 121 to an external battery control unit (not shown), for example.

[0027] In addition, the size, number, and position of the temperature sensors 121 are only required to be able to appropriately measure the temperature of the electrode stack 11, and the size, number, and position of the flexible printed circuit board 122 are appropriately determined according to the size, number, and position of the temperature sensors 121.

[0028] The adhesive 123 is a sheet with adhesive properties on both sides, which is used to bond the electrode laminate 11 to the cooler 12. The adhesive 123 is, for example, an adhesive sheet or double-sided tape made of a solid support and an adhesive on the surface of the support.

[0029] like Figure 2 As shown, the adhesive 123 is located at the periphery of the temperature sensor 121 and the flexible printed circuit board 122. If the battery module 10 did not have the adhesive 123, liquid adhesive before the formation of the adhesive layer 124 during the construction of the battery module 10 could potentially flow into the temperature sensor 121. By having the adhesive 123, the thick adhesive 123 acts as a barrier, preventing the liquid adhesive from flowing into the temperature sensor 121.

[0030] However, the adhesive 123 may also have a shape that covers a portion of the flexible printed circuit board 122 from the z-direction, i.e. the stacking direction, as long as the adhesive 123 can prevent the liquid adhesive from flowing into the temperature sensor 121 and the temperature sensor 121 can be properly configured to measure the temperature of the electrode stack 11.

[0031] Furthermore, the thickness of the adhesive 123 is only required to prevent the inflow of liquid adhesive when constructing the battery module 10; for example, a thickness of 1 mm or less is preferred when constructing the battery module 10. Additionally, the adhesive 123 is preferably flexible in order to conform to the surface shapes of the electrode stack 11 and the cooler 12.

[0032] Furthermore, in order to enable heat dissipation from the electrode stack 11 and the temperature sensor 121, the adhesive 123 is preferably made of a raw material with high thermal conductivity. The thermal conductivity of the adhesive 123 is preferably 1.5 W / m·K or higher, more preferably 2.0 W / m·K or higher, and even more preferably 2.5 W / m·K or higher.

[0033] The adhesive layer 124 is formed by curing a liquid adhesive, bonding the electrode laminate 11 to the cooler 12. The adhesive layer 124 is formed, for example, by curing an adhesive containing silicone resin, acrylic resin, or epoxy resin. Furthermore, the adhesive layer 124 preferably has electrical or thermal conductivity.

[0034] Figure 4A This is a YZ cross-sectional view of the battery module involved in the embodiment of this utility model. Figure 4B and Figure 4C A yz cross-sectional view showing the case where the end face shape of the adhesive body of the battery module involved in the embodiment of this utility model has been changed.

[0035] like Figure 4B and Figure 4C As shown, the adhesive 123 preferably has a step or inclination formed on its end face. Figure 4B In the example shown, the adhesive 123 is formed with a step such that the surface on the positive z-axis side is smaller than the surface on the negative z-axis side. Figure 4C In the example shown, the adhesive 123 is inclined such that the area of ​​its end face in the xy plane decreases as it approaches the positive z-axis. By forming a step or incline on the end face of the adhesive 123, the surface area of ​​the end face portion is... Figure 4A Compared to the increase, the heat dissipation effect of the adhesive 123 receiving heat from the electrode laminate 11 is improved.

[0036] In addition, Figure 4B In the example shown, one step is formed on the adhesive 123, but two or more steps can also be formed. Furthermore, in Figure 4C In the example shown, the incline may not be straight; it may also include curves. Additionally, the incline may have one or more protrusions.

[0037] In addition, in order to form a step or inclination on the end face of the adhesive 123, in addition to using an adhesive 123 with a pre-processed end face shape, a step or inclination can also be formed on the end face of the adhesive 123 by stacking multiple adhesives 123 with different shapes.

[0038] As described above, in the battery pack of the present invention, the electrode laminate and the cooler are bonded together by an adhesive, which is a sheet with adhesiveness on both sides and is located at the periphery of the temperature sensor. This provides a battery pack that prevents adhesive from flowing into the area where the temperature sensor is located.

[0039] Next, refer to Figure 5 The manufacturing method of the battery pack involved in the embodiments of this utility model will be described. Figure 5 This is a flowchart illustrating a method for manufacturing a battery pack according to an embodiment of the present invention. The steps shown below are performed, for example, by a manufacturing apparatus such as a laminating machine, which holds the electrode laminate 11 and the cooler 21 and arranges a temperature sensor 121, a flexible printed circuit board 122, an adhesive 123, or a liquid adhesive on the electrode laminate 11 or the cooler 12.

[0040] First, the temperature sensor 121 and the flexible printed circuit board 122 are disposed on the cooler 12 (step S1). However, the temperature sensor 121 and the flexible printed circuit board 122 may also be disposed on the electrode stack 11, as long as the temperature sensor 121 can appropriately measure the temperature of the electrode stack 11 when the battery pack 1 is formed.

[0041] Next, the adhesive 123 is disposed on the cooler 12 such that it is disposed on the periphery of the temperature sensor 121 and the flexible printed circuit board 122 (step S2). However, the adhesive 123 may be disposed on the electrode laminate 11, or on both the electrode laminate 11 and the cooler 12. Alternatively, the temperature sensor 121 and the flexible printed circuit board 122 may be disposed on the cooler 12 in step S1, and the adhesive 123 may be disposed on the electrode laminate 11 in step S2. That is, the temperature sensor 121 and the flexible printed circuit board 122 and the adhesive 123 may be disposed on different surfaces, as long as the adhesive 123 is disposed on the periphery of the temperature sensor 121 and the flexible printed circuit board 122 in step S4 (described later). However, from the viewpoint of easily manufacturing the battery pack 1, it is preferable to arrange the adhesive 123, the temperature sensor 121 and the flexible printed circuit board 122 on the same surface, and more preferably to arrange the adhesive 123, the temperature sensor 121 and the flexible printed circuit board 122 on the cooler 12.

[0042] Furthermore, the end face shape of the adhesive 123 configured in step S2 is preferably as follows: Figure 4B and Figure 4C The end face is shown to have a step or inclination. Furthermore, in step S4 described later, when the electrode laminate 11 is located above the cooler 12, the adhesive 123 preferably has an end face shape such that the area of ​​the surface where the adhesive 123 is bonded to the electrode laminate 11 is smaller than the area of ​​the surface where the adhesive 123 is bonded to the cooler 12. Because the adhesive 123 has... Figure 4B and Figure 4C As shown in the end face shape, in step S4, the adhesive that would flow into the temperature sensor 121 is blocked by the adhesive layer on the end face portion of the adhesive body 123. This increases the surface area of ​​the end face portion of the adhesive body 123 while more effectively preventing the liquid adhesive from flowing into the temperature sensor 121.

[0043] Furthermore, in step S4 described later, when the electrode stack 11 is located below the cooler 12, the adhesive 123 preferably has an end face shape where the area of ​​the surface where the adhesive 123 is bonded to the electrode stack 11 is larger than the area of ​​the surface where the adhesive 123 is bonded to the cooler 12. That is, the end face shape of the adhesive 123 preferably varies depending on the positional relationship between the electrode stack 11 and the cooler 12 and the direction of gravity during the bonding step. This more effectively prevents the liquid adhesive from flowing into the temperature sensor 121 during the bonding step.

[0044] Alternatively, multiple adhesive bodies 123 of different shapes can be stacked by repeating step S2 multiple times, and steps or inclinations can be formed on the end faces of the adhesive bodies 123.

[0045] Next, the liquid adhesive is disposed on the cooler 12 (step S3). However, the liquid adhesive may also be disposed on the electrode laminate 11, or on a surface different from the surface on which one or more of the temperature sensor 121, flexible printed circuit board 122, and adhesive 123 are disposed. However, from the viewpoint of easily manufacturing the battery pack 1, it is preferable to dispose of the liquid adhesive and adhesive 123 on the same surface, and more preferably to dispose of the liquid adhesive, temperature sensor 121, flexible printed circuit board 122, and adhesive 123 on the cooler 12.

[0046] In addition, Figure 5 Step S3, which involves preparing the liquid adhesive, is set after step S2, which involves preparing the adhesive body 123. However, step S3 can also be set before step S2. That is, the adhesive body 123 can be prepared after the liquid adhesive has been prepared.

[0047] Next, the electrode laminate 11 is bonded to the cooler 12 in such a way that the temperature sensor 121, flexible printed circuit board 122, adhesive 123, and liquid adhesive are configured to be substantially coplanar (step S4). In step S4, the liquid adhesive cures to form an adhesive layer 124. Furthermore, the pressure applied during bonding in step S4 is only sufficient to adequately bond the electrode laminate 11 to the cooler 12; no pressure is required as long as the electrode laminate 11 is bonded to the cooler 12.

[0048] As explained above, the method for manufacturing a battery pack according to the embodiments of this utility model involves placing an adhesive on the periphery of a temperature sensor and bonding the electrode laminate to a cooler. This provides a method for manufacturing a battery pack that prevents adhesive from flowing into the area where the temperature sensor is located.

[0049] Furthermore, the battery pack and its manufacturing method described in the embodiments of this utility model can also be applied to battery packs that do not include the temperature sensor 121. In this case, by placing the adhesive 123 at the periphery of the flexible printed circuit board 122 in a manner that prevents liquid adhesive from flowing into the area where the flexible printed circuit board 122 is disposed, the same effect as described in this utility model can be obtained.

Claims

1. A battery pack, characterized in that, The internal space houses a battery module, which is composed of an electrode stack and a cooler stacked together with a temperature sensor as a barrier. The electrode stack and the cooler are bonded together by an adhesive. The adhesive is a sheet material that is adhesive on both sides.

2. The battery pack according to claim 1, characterized in that, The adhesive is disposed on the periphery of the temperature sensor. The electrode laminate and the cooler are bonded at the periphery by the adhesive body, and at the location outside the periphery by an adhesive layer, which is formed by curing a liquid adhesive.

3. The battery pack according to claim 1 or 2, characterized in that, A step or inclination is formed on the end face of the adhesive to increase the surface area of ​​the end face.

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