Battery

Abstract

A battery is provided with: a rectangular single cell stack in which a plurality of rectangular single cells, each of which has terminals on both end surfaces in the longitudinal direction, are stacked; and a case that houses the cell stack. The unit cell stack includes metallic binding members that bind both lower ends of the plurality of rectangular unit cells in the longitudinal direction, and the binding members are fixed to the case with a thermally conductive adhesive.

Description

Technical Field

[0001] This disclosure relates to batteries. Background Technology

[0002] In existing batteries, terminals are provided on the upper surface of each stacked square cell. In recent years, batteries have also been developed, as disclosed in Patent Document 1, in which terminals are provided on the end faces of each stacked square cell along its length.

[0003] Patent Document 1: U.S. Patent Application Publication No. 2022 / 0302533 Utility Model Content

[0004] When the battery is charged, the temperature near the terminals in each prismatic cell rises. That is, there is a problem of localized temperature rise inside the prismatic cell. This problem becomes particularly pronounced during rapid charging.

[0005] This disclosure was made in view of the following situation, providing a battery capable of suppressing local temperature rise inside a square single cell during charging.

[0006] The battery involved in one of the solutions disclosed herein has the following characteristics:

[0007] A rectangular parallelepiped-shaped single-cell stack is composed of multiple square single cells stacked together, each with terminals at both ends along its length; and

[0008] A housing that contains the single battery stack.

[0009] in,

[0010] The single-cell stack includes metal restraint members that bind the lower ends of the plurality of square single cells along their length.

[0011] The restraint member is fixed to the housing by a thermally conductive adhesive.

[0012] In the battery disclosed herein, the two lower ends of the single-cell stack along its length are respectively bound by metal binding members, which are fixed to the casing by a thermally conductive adhesive. Therefore, heat generated near the terminals during charging can be dissipated to the casing via the binding members and the thermally conductive adhesive. As a result, localized temperature rise inside the prismatic single cell during charging can be suppressed.

[0013] Alternatively, an insulating plate can be provided between the plurality of square single cells and the binding member, and through holes in the insulating plate, which are respectively arranged corresponding to the plurality of square single cells, are filled with an insulating and thermally conductive material. With this structure, the thermal conductivity between the square single cells and the binding member can be improved while ensuring insulation between them.

[0014] Alternatively, the thermally conductive material can be the same material as the thermally conductive adhesive. With this structure, the battery can be easily manufactured.

[0015] Alternatively, a cooler may be provided on the underside of the bottom plate of the housing. With such a structure, the heat generated in the single-cell stack during charging can be more effectively dissipated from the bottom plate of the housing via the binding members and thermally conductive adhesive.

[0016] Alternatively, the restraining member may be an L-shaped metal strip.

[0017] According to this disclosure, a battery is provided that can suppress local temperature rise inside a square single cell during charging.

[0018] The above and other objects, features and advantages of this disclosure will become more fully understood from the detailed description and accompanying drawings given below. Attached Figure Description

[0019] Figure 1 This is a perspective view showing a single-cell stack in a battery according to the first embodiment.

[0020] Figure 2 This is a perspective view showing a single-cell stack in a battery according to the first embodiment.

[0021] Figure 3 This is a cross-sectional view showing the battery according to the first embodiment.

[0022] Figure 4 This is a perspective view showing the configuration of the insulating plate IP1 relative to the square single cells C1 to C6.

[0023] Figure 5 This is a perspective view showing the configuration of the insulating plate IP2 relative to the square single cells C1 to C6. Detailed Implementation

[0024] Hereinafter, specific embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. However, the present disclosure is not limited to the following embodiments. In addition, for the sake of clarity, the following description and drawings have been appropriately simplified.

[0025] (First Implementation)

[0026] First, refer to Figures 1-3 The configuration of the battery according to the first embodiment will be described. Figure 1 and Figure 2 All are perspective views showing a single-cell stack in the battery according to the first embodiment. Figure 3 This is a cross-sectional view showing the battery according to the first embodiment.

[0027] The battery described in this embodiment is used, for example, as a vehicle battery. While there are no particular limitations on the vehicle equipped with the battery described in this embodiment, it may include, for example, an electric vehicle, a hybrid vehicle, or a fuel cell vehicle that can be driven using electricity supplied from the battery.

[0028] Furthermore, it is only natural that... Figures 1-3 The right-handed XYZ orthogonal coordinate system shown in the other accompanying figures is for ease of illustrating the positional relationships of the constituent elements. Figure 1 In general, the positive Z-axis is the vertical direction, and the XY plane is the horizontal plane, which is common to all the attached diagrams.

[0029] like Figure 3 As shown, the battery according to the first embodiment includes a single-cell stack CS, an upper casing UC, a lower casing LC, and a cooler CO. Here, the single-cell stack CS is as follows: Figure 1 and Figure 2 As shown, it includes square single cells C1 to C6, busbars B1 to B5, and metal strips MB1 and MB2, and as... Figure 3 As shown, it has adhesive layers AL1 and AL2, insulating plates IP1 and IP2, and thermally conductive layers TL1 and TL2.

[0030] In addition, Figure 3 In the diagram, the square single cell C1 and the cooler CO are shown in a side view rather than a sectional view.

[0031] First, refer to Figures 1-3 The structure of a single-cell stack (CS) is explained.

[0032] like Figure 1 and Figure 2 As shown, the square single cells C1 to C6 are rectangular single cells in the shape of cuboids extending along the Y-axis. The square single cells C1 to C6 are stacked along the thickness direction (X-axis direction) to form a single cell stack CS. The square single cells C1 to C6 are, for example, secondary batteries such as lithium-ion batteries and nickel-metal hydride batteries.

[0033] In addition, Figure 1 and Figure 2 In the diagram, the single-cell stack CS is shown in a simplified manner. Figure 1 and Figure 2The single-cell stack CS shown consists of six square single cells C1 to C6, but it is usually composed of more square single cells. On the other hand, there is no particular limitation on the number of square single cells that make up the single-cell stack CS, as long as there are multiple cells.

[0034] Additionally, heat insulation plates (not shown) and spacers for adjusting the spacing can be inserted between adjacent square single cells.

[0035] Furthermore, end plates (not shown) can also be provided at both ends of the stacking direction (X-axis direction) of the single cell stack CS.

[0036] like Figure 1 As shown, a positive terminal PT1 is provided on one end face (the negative Y-axis side end face) of the square single cell C1 along its length. Although not specifically limited, Figure 1 The positive terminal PT1 shown is rectangular in shape when viewed in the XZ plane, and is positioned to protrude outward from the end face of the square single cell C1. Additionally, Figure 1 The positive terminal PT1 shown is located on the upper side (positive Z-axis side) of the end face of the square single cell C1. The positive terminal PT1 is made of a metallic material such as copper, which has excellent conductivity.

[0037] Similarly, as Figure 1 As shown, a negative terminal NT2 is provided on one end face (the negative Y-axis side face) of square single cell C2 adjacent to square single cell C1 along its length. A positive terminal PT3 is provided on one end face (the negative Y-axis side face) of square single cell C3 adjacent to square single cell C2 along its length. A negative terminal NT4 is provided on one end face (the negative Y-axis side face) of square single cell C4 adjacent to square single cell C3 along its length. A positive terminal PT5 is provided on one end face (the negative Y-axis side face) of square single cell C5 adjacent to square single cell C4 along its length. A negative terminal NT6 is provided on one end face (the negative Y-axis side face) of square single cell C6 adjacent to square single cell C5 along its length.

[0038] like Figure 1 As shown, the negative terminal NT2 of square single cell C2, the positive terminal PT3 of square single cell C3, the negative terminal NT4 of square single cell C4, the positive terminal PT5 of square single cell C5, and the negative terminal NT6 of square single cell C6 have the same shape as the positive terminal PT1 of square single cell C1, and are configured in the same way.

[0039] And, as Figure 1As shown, the positive terminal PT1 of adjacent square single-cell C1 and the negative terminal NT2 of square single-cell C2 are electrically connected by a plate-shaped busbar B1. Similarly, the positive terminal PT3 of adjacent square single-cell C3 and the negative terminal NT4 of square single-cell C4 are electrically connected by a plate-shaped busbar B3. Likewise, the positive terminal PT5 of adjacent square single-cell C5 and the negative terminal NT6 of square single-cell C6 are electrically connected by a plate-shaped busbar B5.

[0040] On the other hand, such as Figure 2 As shown, a negative terminal NT1 is provided on the other end face (the positive Y-axis side end face) along the length of the square single cell C1. Although not specifically limited, Figure 2 The negative extreme NT1 shown is Figure 1 The positive terminal PT1 shown is also rectangular in shape when viewed in the XZ plane, and is positioned to protrude outward from the end face of the square single cell C1. Additionally, Figure 2 The negative extreme NT1 shown is Figure 1 The positive terminal PT1 shown is also located on the upper side (positive Z-axis side) of the end face of the square single cell C1. The negative terminal NT1 is the same as the positive terminal PT1, and is made of a metal material such as copper with excellent conductivity.

[0041] Similarly, as Figure 2 As shown, a positive terminal PT2 is provided on the other end face (positive Y-axis side face) of square single cell C2, which is adjacent to square single cell C1, along its length. A negative terminal NT3 is provided on the other end face (positive Y-axis side face) of square single cell C3, which is adjacent to square single cell C2, along its length. A positive terminal PT4 is provided on the other end face (positive Y-axis side face) of square single cell C4, which is adjacent to square single cell C3. A negative terminal NT5 is provided on the other end face (positive Y-axis side face) of square single cell C5, which is adjacent to square single cell C4. A positive terminal PT6 is provided on the other end face (positive Y-axis side face) of square single cell C6, which is adjacent to square single cell C5, along its length.

[0042] like Figure 2 As shown, the positive terminal PT2 of square single cell C2, the negative terminal NT3 of square single cell C3, the positive terminal PT4 of square single cell C4, the negative terminal NT5 of square single cell C5, and the positive terminal PT6 of square single cell C6 have the same shape as the negative terminal NT1 of square single cell C1, and are configured in the same way.

[0043] And, as Figure 2As shown, the positive terminal PT2 of the adjacent square single cell C2 and the negative terminal NT3 of the square single cell C3 are electrically connected by a plate-shaped busbar B2. Similarly, the positive terminal PT4 of the adjacent square single cell C4 and the negative terminal NT5 of the square single cell C5 are electrically connected by a plate-shaped busbar B4.

[0044] Like this, in Figure 1 and Figure 2 In the single-cell stack CS shown, square single cells C1 to C6 are connected in series through busbars B1 to B5.

[0045] also, Figure 2 The negative terminal NT1 of the square single cell C1 shown is not particularly limited, but it can be connected to the positive terminal of other single cell stacks, for example, via a busbar (not shown). Additionally, Figure 2 The positive terminal PT6 of the square single cell C6 shown is not particularly limited, but can be connected to the negative terminal of other single cell stacks, for example, via a busbar (not shown). With this structure, multiple single cell stacks can be connected in series, for example.

[0046] Figure 1 and Figure 2 The busbars B1 to B5 shown have the same structure, so busbar B1 will be described.

[0047] like Figure 1 As shown, busbar B1 is a plate-shaped component that electrically connects the positive terminal PT1 of adjacent square single cells C1 to the negative terminal NT2 of square single cells C2. Busbar B1 is made of, for example, a metallic material such as copper with excellent conductivity.

[0048] like Figure 1 As shown, the busbar B1 is, for example, a plate-like member that is rectangular in shape when viewed in the XZ plane. The busbar B1 is configured to cover the positive terminal PT1 of the square single cell C1 and the negative terminal NT2 of the square single cell C2 in a substantially integral manner. The busbar B1 has a pair of welded portions WP1 and WP2 that are respectively welded to the positive terminal PT1 of the adjacent square single cell C1 and the negative terminal NT2 of the square single cell C2.

[0049] Although there are no specific restrictions, Figure 1 The welded portions WP1 and WP2 shown are located at both ends in the X-axis direction on the lower side (negative Z-axis direction side) of busbar B1. Figure 1 The welded sections WP1 and WP2 before welding are shown. Figure 1 The welded areas WP1 and WP2 shown have undergone countersinking, resulting in a thinner plate compared to other areas. Additionally, Figure 1The welded parts WP1 and WP2 shown have a circular shape when viewed in the XZ plane, and have a through hole in the center.

[0050] While the welding method is not particularly limited, for example, by irradiating the welding section WP1 with a laser beam from the negative Y-axis direction, the busbar B1 is welded to the positive terminal PT1 of the square single cell C1 at the welding section WP1. Similarly, by irradiating the welding section WP2 with a laser beam from the negative Y-axis direction, the busbar B1 is welded to the negative terminal NT2 of the square single cell C2 at the welding section WP2.

[0051] like Figure 1 and Figure 2 As shown, metal strips (constraint members) MB1 and MB2 are L-shaped metal members with YZ cross sections that extend along the stacking direction along the entire length of the single cell stack CS. Metal strips MB1 and MB2 constrain the two lower ends of the square single cells C1 to C6 (i.e., the single cell stack CS) along the length direction.

[0052] In addition, metal strips MB1 and MB2 can also be divided into multiple strips along the entire length of a single cell stack CS.

[0053] More specifically, such as Figure 3 As shown, the metal strip MB1 is configured in an L-shape with a YZ cross-section along the lower corner of the square single cells C1 to C6 in the negative Y-axis direction, and has a base plate supporting the bottom surface of the square single cells C1 to C6 and a side plate supporting the end surfaces of the square single cells C1 to C6. Similarly, the metal strip MB2 is configured in an L-shape with a YZ cross-section along the lower corner of the square single cells C1 to C6 in the positive Y-axis direction, and has a base plate supporting the bottom surface of the square single cells C1 to C6 and a side plate supporting the end surfaces of the square single cells C1 to C6.

[0054] The metal strips MB1 and MB2 may not be L-shaped with a YZ cross section; they may be flat, for example.

[0055] like Figure 3 As shown, adhesive layer AL1 is made of thermally conductive adhesive and fixes metal strip MB1 to the bottom plate of the lower housing LC. Similarly, adhesive layer AL2 is made of thermally conductive adhesive and fixes metal strip MB2 to the bottom plate of the lower housing LC.

[0056] The thermally conductive adhesives constituting the adhesive layers AL1 and AL2 are, for example, adhesives with a thermal conductivity of 1 W / m·K or higher. The thermally conductive adhesives may also have insulating properties.

[0057] In addition, metal strips MB1 and MB2 can also be fixed to the side plates of the housing, the support frame of the housing, etc., via adhesive layers AL1 and AL2.

[0058] exist Figure 3In the battery shown, heat generated near the positive terminal PT1 of the square single cell C1 during charging can be dissipated to the bottom plate of the lower casing LC via the metal strip MB1 and the adhesive layer AL1. Similarly, heat generated near the negative terminal NT1 of the square single cell C1 during charging can be dissipated to the bottom plate of the lower casing LC via the metal strip MB2 and the adhesive layer AL2. That is, by using the adhesive layers AL1 and AL2 to connect the metal strips MB1 and MB2 to the lower casing LC, local temperature rise inside the square single cell C1 during charging can be suppressed.

[0059] Here, besides Figure 3 In addition, refer to Figure 4 and Figure 5 The IP1 and IP2 of the insulation board are explained. Figure 4 This is a perspective view showing the configuration of the insulating plate IP1 relative to the square single cells C1 to C6. Figure 5 This is a perspective view showing the configuration of the insulating plate IP2 relative to the square single cells C1 to C6.

[0060] like Figure 4 and Figure 5 As shown, insulating plates IP1 and IP2 are L-shaped insulating members with YZ cross sections that extend along the stacking direction along the entire length of the single cell stack CS. Insulating plates IP1 and IP2 are, for example, made of resin.

[0061] Here, as Figure 4 As shown, six through holes TH1 are provided on the insulating plate IP1, corresponding to the square single cells C1 to C6 respectively. Similarly, as... Figure 5 As shown, six through holes TH2 are provided on the insulating plate IP2 in a manner corresponding to the square single cells C1 to C6 respectively.

[0062] Figure 4 and Figure 5 The through holes TH1 and TH2 shown are rectangular in shape when viewed in the XZ plane, but they can also be circular or elliptical, for example, without any limitation.

[0063] On the other hand, such as Figure 3 As shown, insulating plate IP1 is located at the lower corner of the square single cells C1-C6 on the negative Y-axis side, between the square single cells C1-C6 and the metal strip MB1, electrically insulating the square single cells C1-C6 from the metal strip MB1. Similarly, insulating plate IP2 is located at the lower corner of the square single cells C1-C6 on the positive Y-axis side, between the square single cells C1-C6 and the metal strip MB2, electrically insulating the square single cells C1-C6 from the metal strip MB2.

[0064] In addition, although there are no specific restrictions, Figure 3The insulating plates IP1 and IP2 shown have an L-shaped YZ cross section corresponding to the metal strips MB1 and MB2, and are slightly larger than the metal strips MB1 and MB2, and are arranged to extend from the metal strips MB1 and MB2.

[0065] The thermally conductive layer TL1 is made of a thermally conductive material with insulating properties, such as... Figure 3 As shown, the thermally conductive layer TL1 fills the through holes TH1 provided on the insulating plate IP1. That is, the thermally conductive layer TL1 connects the metal strip MB1 to the square single cells C1 to C6 in a way that is both electrically insulated and thermally conductive.

[0066] Similarly, the thermally conductive layer TL2 is made of an insulating and thermally conductive material and fills the through holes TH2 provided on the insulating plate IP2. That is, the thermally conductive layer TL2 connects the metal strip MB2 to the square single cells C1 to C6 in an electrically insulating and thermally conductive manner.

[0067] Based on this structure, Figure 3 In the battery shown, heat generated near the positive terminal PT1 of the square single cell C1 during charging is dissipated to the bottom plate of the lower casing LC via the thermally conductive layer TL1, the metal strip MB1, and the adhesive layer AL1. Similarly, heat generated near the negative terminal NT1 of the square single cell C1 during charging is dissipated to the bottom plate of the lower casing LC via the thermally conductive layer TL2, the metal strip MB2, and the adhesive layer AL2.

[0068] That is, by connecting the metal strips MB1 and MB2, which are connected to the lower housing LC by adhesive layers AL1 and AL2, to the square single cells C1 to C6 by thermally conductive layers TL1 and TL2, it is possible to further suppress the local temperature rise inside the square single cell C1 during charging.

[0069] Furthermore, the thermally conductive materials constituting the thermally conductive layers TL1 and TL2 can also be the same materials as the thermally conductive adhesives constituting the adhesive layers AL1 and AL2. With this structure, it is easy to manufacture batteries.

[0070] Furthermore, as long as the square single cells C1 to C6 are insulated from the metal strips MB1 and MB2, the insulating plates IP1 and IP2 are not necessary. Therefore, the thermal conductive layers TL1 and TL2 are also not necessary.

[0071] like Figure 3 As shown, the upper shell UC and the lower shell LC constitute the housing for the single-cell stack CS. The upper shell UC is a metal plate covering the upper surface of the single-cell stack CS, and the lower shell LC is a metal plate supporting the bottom surface of the single-cell stack CS. The bottom surface of the single-cell stack CS (i.e., square single cells C1 to C6) is electrically insulated from the upper surface of the lower shell LC, for example, by a thermally conductive layer with insulating properties (not shown).

[0072] In addition, multiple single-cell stacks CS can be arranged along the Y-axis inside the housing (upper housing UC and lower housing LC).

[0073] The cooler CO cools the single-cell stack CS, i.e., the square single cells C1 to C6. For example... Figure 3 As shown, the cooler CO extends along the stacking direction (X-axis direction) along the entire length of the single cell stack CS while contacting the bottom surface of the lower housing LC. Although not specifically limited, multiple refrigerant pipes extending along the X-axis direction are arranged along the Y-axis direction inside the cooler CO. The refrigerant flowing inside the refrigerant pipes is, for example, water.

[0074] The central portion of the square single cells C1 to C6 along the length direction (Y-axis direction) is cooled by the cooler CO via the lower casing LC. On the other hand, the ends of the square single cells C1 to C6 along the length direction are cooled by the cooler CO via the thermally conductive layer TL1, the metal strip MB1, the adhesive layer AL1, and the lower casing LC.

[0075] As described above, in the battery of this embodiment, the two lower ends of the single cell stack CS in the longitudinal direction are respectively bound by L-shaped metal strips MB1 and MB2, and the metal strips MB1 and MB2 are fixed to the bottom plate of the lower shell LC by adhesive layers AL1 and AL2 made of thermally conductive adhesive.

[0076] Therefore, the heat generated near the positive terminals PT1-PT6 and negative terminals NT1-NT6 of the square single cells C1-C6 during charging can be dissipated to the bottom plate of the lower casing LC via the metal strips MB1 and MB2 and the adhesive layers AL1 and AL2. As a result, the local temperature rise inside the square single cells C1-C6 during charging can be suppressed.

[0077] It will be apparent from the above description that embodiments of this disclosure can be varied in many ways. Such variations should not be considered a departure from the spirit and scope of this disclosure, and all such modifications that are obvious to those skilled in the art are intended to be included within the scope of the claims.

Claims

1. A battery comprising: A rectangular parallelepiped-shaped single-cell stack is composed of multiple square single cells stacked together, each with terminals at both ends along its length; and A housing that contains the single battery stack. in, The single-cell stack includes metal restraint members that bind the lower ends of the plurality of square single cells along their length. The restraint member is fixed to the housing by a thermally conductive adhesive.

2. The battery according to claim 1, wherein, An insulating plate is provided between the plurality of square single cells and the binding member. The through holes in the insulating plate, which are arranged in a manner corresponding to the plurality of square single cells respectively, are filled with an insulating and thermally conductive material.

3. The battery according to claim 2, wherein, The thermally conductive material is the same material as the thermally conductive adhesive.

4. The battery according to any one of claims 1 to 3, wherein, A cooler is also provided on the underside of the bottom plate of the housing.

5. The battery according to any one of claims 1 to 3, wherein, The restraining member is a metal strip with an L-shaped cross-section.

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