Battery cell

Abstract

To provide a battery cell capable of preventing condensate water from penetrating from an overlapping portion of an insulating film to thereby suppress a decrease in insulation. The battery cell according to the present application includes: a square outer body that houses an electrode body; and an insulating film that covers a surface portion of the outer body other than a lid portion, the insulating film being formed at an overlapping portion where at least one surface portion of the outer body other than the lid portion overlaps, and a heat conducting member being in contact with the overlapping portion to seal the overlapping portion.

Description

Technical Field

[0001] This invention relates to battery cells. Background Technology

[0002] Patent document 1 discloses a battery cell with an insulating film attached to the side of the outer can.

[0003] [Existing Technical Documents]

[0004] [Patent Literature]

[0005] Patent Document 1: Japanese Patent Application Publication No. 2013-033668 Summary of the Invention

[0006] [The problem the invention aims to solve]

[0007] However, as disclosed in Patent Document 1, if the insulating film is only attached to the outer canister, when the battery pack is mounted in a vehicle, condensation water can seep in from the overlapping part of the insulating film, which may reduce the insulation performance.

[0008] The present invention was made in view of the above-mentioned problems, and its object is to provide a battery cell that can prevent condensation water from seeping in from the overlapping part of the insulating film and thus suppress the reduction of insulation.

[0009] [Methods used to solve problems]

[0010] To address the aforementioned issues and achieve the objectives, the battery cell of the present invention comprises: a square outer casing that houses electrode bodies; and an insulating film that covers the portion of the outer casing other than the cover portion, wherein the insulating film is formed on an overlapping portion of at least one portion of the outer casing other than the cover portion, thereby sealing the heat-conducting component by contacting the overlapping portion.

[0011] Therefore, the battery cell of the present invention can use the heat conduction component to seal the overlapping part of the insulating film, prevent the intrusion of condensate water, and suppress the reduction of insulation.

[0012] Alternatively, as described above, the cover portion can also be one of the two end portions of the battery cell in the width direction.

[0013] This can improve the construction efficiency of battery cells.

[0014] Alternatively, the heat conduction component described above can also be a cooler.

[0015] Therefore, the cooler can be shared for sealing the overlapping parts and cooling the battery cells, thus enabling a reduction in the number of components and saving space.

[0016] [Invention Effects]

[0017] The battery cell involved in this invention has the following effects: it can use the heat conduction component to seal the overlapping part of the insulating film, prevent the intrusion of condensate water, and suppress the reduction of insulation. Attached Figure Description

[0018] Figure 1 This is a diagram showing the outer casing and insulating film of the battery cell involved in the embodiment.

[0019] Figure 2 This diagram shows step two of the covering process, in which an insulating film is used to cover the outer casing.

[0020] Figure 3 This diagram illustrates step three of the covering process, where an insulating film is used to cover the outer casing.

[0021] Figure 4 This diagram shows step four of the covering process, in which an insulating film is used to cover the outer casing.

[0022] Figure 5 This diagram illustrates step five of the covering process, where an insulating film is used to cover the outer casing.

[0023] Figure 6 This diagram shows a state where the overlapping portion of the insulating film is sealed by a heat-conducting component.

[0024] Figure 7 This diagram illustrates the use of two insulating films to cover the outer casing.

[0025] Figure 8 This diagram shows a state where the upper and lower surfaces of the outer casing overlap. Detailed Implementation

[0026] The following describes embodiments of the battery cell according to the present invention. However, the present invention is not limited to these embodiments.

[0027] Figure 1 This diagram illustrates the outer casing 2 and insulating film 3 of the battery cell 1 according to the embodiment. Furthermore, Figure 1 This diagram also illustrates step one of the covering process of covering the outer casing 2 with insulating film 3, which will be described later.

[0028] like Figure 1 As shown, the battery cell 1 according to the embodiment includes a square outer casing 2 for housing electrode bodies (not shown) and an insulating film 3 covering the outer casing 2. Figure 1 The "X" in the figure represents the width direction of battery cell 1, which will also be abbreviated as "width direction X" in the following description. Additionally, Figure 1 In this context, "Y" represents the thickness direction of battery cell 1, which will also be abbreviated as "thickness direction Y" in the following explanation. Additionally, Figure 1 In this context, "Z" refers to the height direction of battery cell 1, which will also be abbreviated as "height direction Z" in the following explanation. Furthermore, in... Figure 1 In this configuration, the width direction X of the battery cell 1 is the same as the width direction of the outer casing 2 and the short side direction of the insulating film 3. Furthermore, in... Figure 1 In the diagram, the thickness direction Y of battery cell 1 is the same as the thickness direction of outer casing 2 and the length direction of insulating film 3. Furthermore, in... Figure 1 In the figure, the height direction Z of battery cell 1 is the same as the height direction of outer body 2.

[0029] The outer casing 2 has a first end portion 10A, a second end portion 10B, a first side portion 11A, a second side portion 11B, an upper surface portion 12A, and a lower surface portion 12B. Two electrode terminals 21A and 22A are provided on the first end portion 10A. Similarly, two electrode terminals 21B and 22B are provided on the second end portion 10B. The first end portion 10A and the second end portion 10B are configured as detachable covers that can be attached to and detached from the main body of the outer casing 2. When storing electrodes or the like inside the outer casing 2, the first end portion 10A and the second end portion 10B are removed from the main body of the outer casing 2. Furthermore, the main body of the outer casing 2 is formed by the first side portion 11A, the second side portion 11B, the upper surface portion 12A, and the lower surface portion 12B. In the battery cell 1 according to the embodiment, the first end portion 10A, which is provided with electrode terminals 21A and 22A, and the second end portion 10B, which is provided with electrode terminals 21B and 22B, are the cover portions of the outer body 2 at both ends in the width direction (width direction X), thereby improving the construction efficiency.

[0030] like Figure 1 As shown, the insulating film 3 has a first upper surface covering portion 32A, a first side surface covering portion 31A, a lower surface covering portion 33, a second side surface covering portion 31B, and a second upper surface covering portion 32B from one end to the other along its length direction (thickness direction Y). Furthermore, the single-dotted lines shown on the insulating film 3 represent creases when the insulating film 3 is bent, and also indicate the boundaries of adjacent covering portions.

[0031] Furthermore, at least one side of the insulating film 3, i.e. the side that can contact the outer casing 2, has an adhesive layer for bonding with the outer casing 2. This adhesive layer is formed, for example, by applying an adhesive.

[0032] The battery cell 1 involved in the implementation method, for example, has been used Figures 1 to 5The following steps one through five are described in detail, in which the insulating film 3 is used to cover all surfaces of the outer casing 2 except for the first end portion 10A and the second end portion 10B, which serve as the cover. Furthermore, in the battery cell 1 according to the embodiment, at least one surface of the outer casing 2 other than the first end portion 10A and the second end portion 10B, namely the upper surface portion 12A, is sealed by overlapping the first upper surface covering portion 32A and the second upper surface covering portion 32B of the insulating film 3.

[0033] Next, use Figures 1 to 5 Steps one through five of the covering process of covering the outer casing 2 with insulating film 3 in the battery cell 1 according to the embodiment will be described. Figure 2 This diagram shows step two of the covering process where the insulating film 3 covers the outer casing 2. Figure 3 This is a diagram showing step three of the covering process of covering the outer casing 2 with insulating film 3. Figure 4 This is a diagram showing step four of the covering process of covering the outer casing 2 with insulating film 3. Figure 5 This is a diagram showing step five of the covering process of covering the outer casing 2 with insulating film 3.

[0034] First, in step one, as Figure 1 As shown, the lower surface portion 12B of the outer casing 2 is mounted on the lower surface covering portion 33 of the insulating film 3.

[0035] Next, in step two, as Figure 2 As shown, the insulating film 3 is bent so that the first side covering portion 31A of the insulating film 3 covers the first side portion 11A of the outer casing 2, so that the first side covering portion 31A is adhered to the first side portion 11A.

[0036] Next, in step three, as Figure 3 As shown, the insulating film 3 is bent such that the first upper surface covering portion 32A covers a portion of the upper surface portion 12A of the outer casing 2, so that the first upper surface covering portion 32A is adhered to the upper surface portion 12A.

[0037] Next, in step four, as Figure 4 As shown, the insulating film 3 is bent so that the second side covering portion 31B of the insulating film 3 covers the second side portion 11B of the outer casing 2, so that the second side covering portion 31B is adhered to the second side portion 11B.

[0038] Next, in step five, as Figure 5As shown, the insulating film 3 is bent such that a portion of the upper surface portion 12A of the outer casing 2 and a portion of the first upper surface portion 32A of the insulating film 3 are covered by the second upper surface covering portion 32B of the insulating film 3, so that the second upper surface covering portion 32B overlaps with the first upper surface covering portion 32A and is bonded to the upper surface portion 12A and the first upper surface covering portion 32A. Thus, in the outer casing 2, the battery cell 1 according to the embodiment is covered by the insulating film 3 on all surfaces except the first end portion 10A and the second end portion 10B.

[0039] Figure 6 This diagram shows the state in which the overlapping portion 30 of the insulating film 3 is sealed by the heat conduction component 4 blocking the insulating film 3.

[0040] In battery cell 1, the overlapping portion 30 of the first upper surface covering portion 32A and the second upper surface covering portion 32B of the insulating film 3 is used when multiple battery cells 1 are stacked to form a battery pack, such as Figure 6 As shown, the flat portion of the heat conduction component 4 is made to contact and block it, or it is sealed by using an adhesive.

[0041] Alternatively, for example, the overlapping portion 30 of the insulating film 3 is preferably used as the cooling surface of the battery cell 1, and the flat portion of the cooler is made to contact and cover the overlapping portion 30 as a heat conduction component 4, thereby sealing it. As a result, the cooler (heat conduction component 4) can be used for both sealing the overlapping portion 30 and cooling the battery cell 1, thus reducing the number of components, saving space, and improving construction efficiency.

[0042] In the battery cell 1 of the embodiment, the overlapping portion 30 of the insulating film 3 is sealed by the heat conduction member 4 to prevent condensation water from seeping in from the overlapping portion 30, thereby suppressing the reduction of insulation.

[0043] Figure 7 This diagram illustrates the use of two insulating films, 3A and 3B, to cover the outer casing 2. Figure 8 This diagram shows that overlapping portions 30A and 30B are formed on the upper surface portion 12A and the lower surface portion 12B of the outer casing 2.

[0044] In the battery cell 1 involved in the implementation method, such as Figure 7 As shown, it can also be configured such that the outer casing 2 is covered by two insulating films 3A and 3B. Figure 7 As shown, the insulating film 3A has a first upper surface covering portion 320A, a first side surface covering portion 310A, and a first lower surface covering portion 330A along the short side direction (height direction Z) from one end to the other. Additionally, as... Figure 7As shown, the insulating film 3B has a second upper surface covering portion 320B, a second side surface covering portion 310B, and a second lower surface covering portion 330B in the short side direction (height direction Z) of the insulating film 3B from one end to the other.

[0045] Then, as Figure 7 As shown, the first side covering portion 310A of the insulating film 3A is bonded to the first side covering portion 11A of the outer body 2, and the second side covering portion 310B of the insulating film 3B is bonded to the second side covering portion 11B of the outer body 2.

[0046] Next, as Figure 8 As shown, the insulating film 3A is bent such that a portion of the upper surface portion 12A of the outer casing 2 is covered by the first upper surface covering portion 320A, thereby bonding the first upper surface covering portion 320A to the upper surface portion 12A. Then, the insulating film 3B is bent such that a portion of both the upper surface portion 12A and the first upper surface covering portion 320A of the outer casing 2 are covered by the second upper surface covering portion 320B, thereby overlapping and bonding the second upper surface covering portion 320B to both the first upper surface covering portion 320A and the first upper surface covering portion 320A. Thus, an overlapping portion 30A is formed on the upper surface portion 12A of the outer casing 2, where the first upper surface covering portion 320A and the second upper surface covering portion 320B overlap.

[0047] In addition, such as Figure 8 As shown, the insulating film 3A is bent such that a portion of the lower surface portion 12B of the outer casing 2 is covered by the first lower surface covering portion 330A, thereby bonding the first lower surface covering portion 330A to the lower surface portion 12B. Then, the insulating film 3B is bent such that a portion of both the lower surface portion 12B of the outer casing 2 and the first lower surface covering portion 330A of the insulating film 3A are covered by the second lower surface covering portion 330B, thereby overlapping and bonding the second lower surface covering portion 330B to both the lower surface portion 12B and the first lower surface covering portion 330A. Thus, an overlapping portion 30B is formed on the lower surface portion 12B of the outer casing 2, where the first lower surface covering portion 330A and the second lower surface covering portion 330B overlap.

[0048] Furthermore, the overlapping portion 30A formed on the upper surface portion 12A of the outer casing 2 and the overlapping portion 30B formed on the lower surface portion 12B of the outer casing 2 are respectively made to contact and block the planar portion of the heat conduction component such as the cooler, or are sealed by bonding with an adhesive. As a result, condensate can be prevented from seeping in from the overlapping portions 30A and 30B formed on the upper surface portion 12A and the lower surface portion 12B of the outer casing 2, and the reduction of insulation can be suppressed.

[0049] [Explanation of reference numerals in the attached figures]

[0050] 1 Battery cell

[0051] 2 outer body

[0052] 3, 3A, 3B insulating films

[0053] 4. Heat conduction components

[0054] 10A First end face

[0055] 10B Second end face

[0056] 11A First side profile

[0057] 11B Second side profile

[0058] 12A Upper Surface

[0059] 12B Lower surface

[0060] Electrode terminals 21A, 21B, 22A, and 22B

[0061] Overlapping parts of 30, 30A, and 30B

[0062] 31B, 310B Second Side Cover

[0063] 31A, 310A First Side Cover

[0064] 32A, 320A First Upper Surface Covering

[0065] 32B, 320B Second Upper Surface Cover

[0066] 33 Lower surface covering

[0067] 330A First Lower Surface Cover

[0068] 330B Second Lower Surface Cover

Claims

1. A battery cell, characterized in that, have: A square outer casing that houses the electrode body; and An insulating film that covers the surface of the outer casing other than the cover portion. The insulating film is formed on at least one overlapping portion of the outer casing, outside the cover portion. The heat-conducting component is brought into contact with the overlapping portion to achieve a seal.

2. The battery cell according to claim 1, characterized in that, The cover portion is the two end portions of the battery cell in the width direction.

3. The battery cell according to claim 1 or 2, characterized in that, The heat-conducting component is a cooler.

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