Battery

Abstract

A battery is provided with a first cell stack and a second cell stack, each of which has a rectangular parallelepiped shape and is formed by stacking a plurality of rectangular cells each having a terminal provided on an end surface in the longitudinal direction. The first cell stack and the second cell stack are arranged so that the first end and the second end in the stacking direction correspond to each other. A root portion of the first end bus bar is fixed to a terminal of the rectangular unit cell located closest to the first end side in the first unit cell stack, and a root portion of the second end bus bar is fixed to a terminal of the rectangular unit cell located closest to the first end side in the second unit cell stack. The front end portion of the second end bus bar is disposed so as to be offset downward from the front end portion of the first end bus bar and toward the first end side, and the front end portion of the first end bus bar and the front end portion of the second end bus bar are disposed so as to be aligned in the stacking direction of the plurality of rectangular unit cells.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to a battery. BACKGROUND

[0002] In the existing battery, a terminal is provided on the upper surface of each prismatic cell that is stacked. In recent years, a battery in which a terminal is provided on the length direction end surface of each prismatic cell that is stacked has also been developed, as disclosed in Patent Literature 1.

[0003] Patent Literature 1: U.S. Patent Application Publication No. 2022 / 0302533 Specification SUMMARY

[0004] The present inventors have developed a battery having a plurality of cell stacks arranged. In the battery in which a terminal is provided on the length direction end surface of each prismatic cell that is stacked, a terminal of a prismatic cell located at the end portion in the stacking direction is fixed with an external connection terminal bus bar. Thus, there is a problem that the distance between the cell stacks arranged increases due to interference between the terminal bus bars.

[0005] The present disclosure was completed in view of such circumstances, and provides a battery capable of suppressing an increase in the distance between a plurality of cell stacks arranged.

[0006] A battery according to an aspect of the present disclosure,

[0007] has a first cell stack and a second cell stack each having a rectangular parallelepiped shape in which a plurality of prismatic cells each having a terminal provided on a length direction end surface are stacked, wherein

[0008] the first cell stack and the second cell stack are arranged so that a first end and a second end in the stacking direction correspond to each other,

[0009] a terminal of a prismatic cell located at a position closest to the first end in the first cell stack is fixed with a root portion of a first terminal bus bar,

[0010] a terminal of a prismatic cell located at a position closest to the first end in the second cell stack is fixed with a root portion of a second terminal bus bar,

[0011] a front end portion of the second terminal bus bar is arranged so as to be offset to the lower side and to the first end side with respect to a front end portion of the first terminal bus bar,

[0012] the front end portion of the first terminal bus bar and the front end portion of the second terminal bus bar are arranged in the stacking direction of the plurality of prismatic cells.

[0013] In the battery according to the present disclosure, a terminal of a square cell located at a position closest to a first end side in a first cell stack is fixed with a root of a first end bus bar, a terminal of a square cell located at a position closest to the first end side in a second cell stack is fixed with a root of a second end bus bar, a front end portion of the second end bus bar is arranged offset to a lower side and to the first end side with respect to a front end portion of the first end bus bar, and the front end portion of the first end bus bar and the front end portion of the second end bus bar are arranged in a stacking direction of the square cells.

[0014] Thus, the first end bus bar and the second end bus bar, which are opposed to each other, do not interfere with each other, and an increase in a spacing between the first cell stack and the second cell stack, which are arranged in line, can be suppressed.

[0015] Also, the front end portion of the first end bus bar can be placed on a first support platform fixed at the first end of the first cell stack, and the front end portion of the second end bus bar can be placed on a second support platform fixed at the first end of the second cell stack. According to such a structure, the positions of the front end portions of the first end bus bar and the second end bus bar can be stabilized.

[0016] Also, a screw provided on the first support platform can be inserted into a through hole provided on the front end portion of the first end bus bar, and a screw provided on the second support platform can be inserted into a through hole provided on the front end portion of the second end bus bar. According to such a structure, the positions of the front end portions of the first end bus bar and the second end bus bar can be more stabilized.

[0017] Also, the first support platform can be fixed to an end plate at the first end of the first cell stack, and the second support platform can be fixed to an end plate at the first end of the second cell stack.

[0018] Also, the first support platform can be bolted to an end plate at the first end of the first cell stack, the second support platform can be bolted to an end plate at the first end of the second cell stack, and the end plate at the first end of the first cell stack and the end plate at the first end of the second cell stack can be arranged offset in the stacking direction. According to such a structure, the bolts that fasten the first support platform and the second support platform do not interfere with each other, and an increase in a spacing between the first cell stack and the second cell stack, which are arranged in line, can be suppressed.

[0019] According to the present disclosure, a battery in which an increase in a spacing between a plurality of cell stacks, which are arranged in line, can be suppressed can be provided.

[0020] The above and other objects, features and advantages of the present disclosure will be more fully understood from the following detailed description taken in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF DRAWINGS

[0021] Figure 1 is a schematic perspective view showing a battery according to the first embodiment.

[0022] Figure 2 is a schematic perspective view showing a battery according to the first embodiment.

[0023] Figure 3 is a schematic side view of the side of the cell stack CS1 opposite the cell stack CS2.

[0024] Figure 4 is a schematic side view of the side of the cell stack CS2 opposite the cell stack CS1.

[0025] Figure 5 is a schematic side view showing the positional relationship between the end bus bar EB11 of the cell stack CS1 and the end bus bar EB21 of the cell stack CS2 on the first end side.

[0026] Figure 6 is a schematic plan view showing the positional relationship between the end bus bar EB11 of the cell stack CS1 and the end bus bar EB21 of the cell stack CS2 on the first end side.

[0027] Figure 7 is a schematic side view showing the positional relationship between the end bus bar EB12 of the cell stack CS1 and the end bus bar EB22 of the cell stack CS2 on the second end side. DETAILED DESCRIPTION

[0028] Hereinafter, a detailed description will be given of a specific embodiment of the present disclosure with reference to the drawings. However, the present disclosure is not limited to the following embodiment. In addition, the following description and drawings are appropriately simplified in order to make the description clear.

[0029] (First Embodiment)

[0030] Configuration of Battery

[0031] First, a description will be given of the configuration of a battery according to the first embodiment with reference to Figures 1-4 Figure 1 is a schematic perspective view showing a battery according to the first embodiment. Figure 2 is a schematic perspective view showing a battery according to the first embodiment. Figure 3 is a schematic side view of the side of the cell stack CS1 opposite the cell stack CS2. Figure 4 is a schematic side view of the side of the cell stack CS2 opposite the cell stack CS1.

[0032] ​The battery according to the present embodiment is used, for example, as a vehicle-mounted battery. The vehicle equipped with the battery according to the present embodiment is not particularly limited, but is, for example, an electric vehicle, a hybrid vehicle, a fuel cell vehicle, or the like that can be driven using electric power supplied from the battery.

[0033] Further, as a matter of course, Figures 1-4 The right-hand XYZ orthogonal coordinate system shown in the drawings is for facilitating the explanation of the positional relationship of the components. In Figure 1 In the drawings, the Z-axis positive direction is generally the vertical upward direction, and the XY plane is generally the horizontal plane, and is common among the drawings.

[0034] As shown in Figure 1 and Figure 2 , the battery according to the first embodiment includes cell stacks CS1 and CS2. As shown in Figure 1 and Figure 2 , the cell stacks CS1 and CS2 are arranged in the X-axis direction. As shown in Figure 1 and Figure 2 , the cell stacks CS1 and CS2 are arranged in the Y-axis direction so that the first end (X-axis negative direction side end portion) and the second end (X-axis negative direction side end portion) in the stacking direction (X-axis direction) correspond to each other, inside a housing (not shown).

[0035] Further, in Figure 1 and Figure 2 , the intervals between the cell stacks CS1 and CS2 are depicted to be wider than actual in order to clearly show the configuration of each of the cell stacks CS1 and CS2. In addition, in Figure 1 and Figure 2 , the cell stacks CS1 and CS2 are depicted to be staggered more in the X-axis direction than actual.

[0036] As shown in Figure 1 and Figure 2 , the cell stacks CS1 and CS2 have substantially the same configuration and each include a plurality of square-shaped cells C1 to C6 and bus bars B1 to B5. In addition, as shown in Figure 3 , the cell stack CS1 includes end plates EP1 and EP2 and end bus bars EB11 and EB12, which are not shown in Figure 1 and Figure 2 . Further, as shown in Figure 4 , the cell stack CS2 includes end plates EP1 and EP2 and end bus bars EB21 and EB22, which are not shown in Figure 1 and Figure 2 .

[0037] As shown in Figure 1 and Figure 2As shown, the square cells C1 to C6 are rectangular parallelepiped-shaped square cells arranged extending in the Y-axis direction. The square cells C1 to C6 are stacked in the thickness direction (X-axis direction) to constitute the cell stacks CS1, CS2. The square cells C1 to C6 are, for example, secondary batteries such as lithium-ion batteries, nickel-hydrogen batteries, and the like.

[0038] Further, in Figure 1 and Figure 2 , the cell stacks CS1, CS2 are simplified. Figure 1 and Figure 2 The cell stacks CS1, CS2 shown in FIG. 1 are constituted by six square cells C1 to C6, but are usually constituted by a larger number of square cells. On the other hand, the number of square cells constituting the cell stacks CS1, CS2 is not particularly limited, and is only required to be plural.

[0039] In addition, between the adjacent square cells, a heat insulating plate, a spacer for adjusting the interval, or the like can be inserted.

[0040] As shown in Figure 1 , in the cell stacks CS1, CS2, a positive electrode terminal PT1 is provided at one end surface (Y-axis negative direction side end surface) in the length direction of the square cell C1. Although not particularly limited, as shown in Figure 2 , the positive electrode terminal PT1 is rectangular in shape when viewed in the XZ plane, and is provided so as to protrude outward from the end surface of the square cell C1. In addition, as shown in Figure 1 , the positive electrode terminal PT1 is provided at the upper side (Z-axis positive direction side) in the end surface of the square cell C1. The positive electrode terminal PT1 is constituted by, for example, a metal material such as copper having excellent electrical conductivity.

[0041] Similarly, as shown in Figure 1 , a negative electrode terminal NT2 is provided at one end surface (Y-axis negative direction side end surface) in the length direction of the square cell C2 adjacent to the square cell C1. A positive electrode terminal PT3 is provided at one end surface (Y-axis negative direction side end surface) in the length direction of the square cell C3 adjacent to the square cell C2. A negative electrode terminal NT4 is provided at one end surface (Y-axis negative direction side end surface) in the length direction of the square cell C4 adjacent to the square cell C3. A positive electrode terminal PT5 is provided at one end surface (Y-axis negative direction side end surface) in the length direction of the square cell C5 adjacent to the square cell C4. A negative electrode terminal NT6 is provided at one end surface (Y-axis negative direction side end surface) in the length direction of the square cell C6 adjacent to the square cell C5.

[0042] As shown in Figure 1As shown, the negative terminal NT2 of the square single cell C2, the positive terminal PT3 of the square single cell C3, the negative terminal NT4 of the square single cell C4, the positive terminal PT5 of the square single cell C5, and the negative terminal NT6 of the square single cell C6 have the same shape as the positive terminal PT1 of the square single cell CI, and are arranged in the same manner.

[0043] On the other hand, as shown in FIG. 1, in the single cell stack CS1, CS2, a positive terminal PT1 is provided at the other end surface (Y-axis positive direction side end surface) in the length direction of the square single cell CI. Although not particularly limited, the positive terminal PT1 is provided so as to protrude outward from the end surface of the square single cell CI, as shown in FIG. 1. Figure 2 Figure 2 The negative terminal NT1 shown in FIG. 1, like the positive terminal PT1 shown in FIG. 1, is rectangular in shape when viewed in the XZ plane, and is provided so as to protrude outward from the end surface of the square single cell CI. In addition, the negative terminal NT1, like the positive terminal PT1, is provided at the upper side (Z-axis positive direction side) in the end surface of the square single cell CI, as shown in FIG. 1. Figure 1 Figure 2 The negative terminal NT1 shown in FIG. 1, like the positive terminal PT1 shown in FIG. 1, is rectangular in shape when viewed in the XZ plane, and is provided so as to protrude outward from the end surface of the square single cell CI. In addition, the negative terminal NT1, like the positive terminal PT1, is provided at the upper side (Z-axis positive direction side) in the end surface of the square single cell CI, as shown in FIG. 1. Figure 1 The negative terminal NT1, like the positive terminal PT1, is composed of, for example, a metal material such as copper, which has excellent electrical conductivity.

[0044] Figure 2 As shown in FIG. 1, in the other end surface (Y-axis positive direction side end surface) in the length direction of the square single cell C2 adjacent to the square single cell CI, a positive terminal PT2 is provided. In the other end surface (Y-axis positive direction side end surface) in the length direction of the square single cell C3 adjacent to the square single cell C2, a negative terminal NT3 is provided. In the other end surface (Y-axis positive direction side end surface) in the length direction of the square single cell C4 adjacent to the square single cell C3, a positive terminal PT4 is provided. In the other end surface (Y-axis positive direction side end surface) in the length direction of the square single cell C5 adjacent to the square single cell C4, a negative terminal NT5 is provided. In the other end surface (Y-axis positive direction side end surface) in the length direction of the square single cell C6 adjacent to the square single cell C5, a positive terminal PT6 is provided.

[0045] As shown in FIG. 1, the positive terminal PT2 of the square single cell C2, the negative terminal NT3 of the square single cell C3, the positive terminal PT4 of the square single cell C4, the negative terminal NT5 of the square single cell C5, and the positive terminal PT6 of the square single cell C6 have the same shape as the negative terminal NT1 of the square single cell CI, and are arranged in the same manner. Figure 2 In this case, as shown in FIG. 1, the positive terminal PT2 of the square single cell C2, the negative terminal NT3 of the square single cell C3, the positive terminal PT4 of the square single cell C4, the negative terminal NT5 of the square single cell C5, and the positive terminal PT6 of the square single cell C6 are provided so as to protrude outward from the end surface of the square single cell C2, C3, C4, C5, and C6, respectively, as shown in FIG. 1.

[0046] Figure 1 ​​​​As shown in FIG. 1, the positive terminal PT1 of the square-shaped single cell CI and the negative terminal NT2 of the square-shaped single cell C2, which are arranged adjacent to each other, are electrically connected by the plate-shaped bus bar Bl at one end surface (Y-axis negative direction side end surface) of the single cell stack CS1. Similarly, the positive terminal PT3 of the square-shaped single cell C3 and the negative terminal NT4 of the square-shaped single cell C4, which are arranged adjacent to each other, are electrically connected by the plate-shaped bus bar B3. Similarly, the positive terminal PT5 of the square-shaped single cell C5 and the negative terminal NT6 of the square-shaped single cell C6, which are arranged adjacent to each other, are electrically connected by the plate-shaped bus bar B5.

[0047] As shown in FIG. 2, the positive terminal PT2 of the square-shaped single cell C2 and the negative terminal NT3 of the square-shaped single cell C3, which are arranged adjacent to each other, are electrically connected by the plate-shaped bus bar B2 at the other end surface (Y-axis positive direction side end surface) of the single cell stack CS1. Similarly, the positive terminal PT4 of the square-shaped single cell C4 and the negative terminal NT5 of the square-shaped single cell C5, which are arranged adjacent to each other, are electrically connected by the plate-shaped bus bar B4. Figure 2 Figure 3 As shown in FIG. 1, the positive terminal PT1 of the square-shaped single cell CI and the negative terminal NT2 of the square-shaped single cell C2, which are arranged adjacent to each other, are electrically connected by the plate-shaped bus bar Bl at one end surface (Y-axis negative direction side end surface) of the single cell stack CS1. Similarly, the positive terminal PT3 of the square-shaped single cell C3 and the negative terminal NT4 of the square-shaped single cell C4, which are arranged adjacent to each other, are electrically connected by the plate-shaped bus bar B3. Similarly, the positive terminal PT5 of the square-shaped single cell C5 and the negative terminal NT6 of the square-shaped single cell C6, which are arranged adjacent to each other, are electrically connected by the plate-shaped bus bar B5.

[0048] As shown in FIG. 1, the positive terminal PT1 of the square-shaped single cell CI and the negative terminal NT2 of the square-shaped single cell C2, which are arranged adjacent to each other, are electrically connected by the plate-shaped bus bar Bl at one end surface (Y-axis negative direction side end surface) of the single cell stack CS1. Similarly, the positive terminal PT3 of the square-shaped single cell C3 and the negative terminal NT4 of the square-shaped single cell C4, which are arranged adjacent to each other, are electrically connected by the plate-shaped bus bar B3. Similarly, the positive terminal PT5 of the square-shaped single cell C5 and the negative terminal NT6 of the square-shaped single cell C6, which are arranged adjacent to each other, are electrically connected by the plate-shaped bus bar B5. Figure 1 Figure 2 As shown in FIG. 1, the positive terminal PT1 of the square-shaped single cell CI and the negative terminal NT2 of the square-shaped single cell C2, which are arranged adjacent to each other, are electrically connected by the plate-shaped bus bar Bl at one end surface (Y-axis negative direction side end surface) of the single cell stack CS1. Similarly, the positive terminal PT3 of the square-shaped single cell C3 and the negative terminal NT4 of the square-shaped single cell C4, which are arranged adjacent to each other, are electrically connected by the plate-shaped bus bar B3. Similarly, the positive terminal PT5 of the square-shaped single cell C5 and the negative terminal NT6 of the square-shaped single cell C6, which are arranged adjacent to each other, are electrically connected by the plate-shaped bus bar B5.

[0049] As shown in FIG. 2, the positive terminal PT2 of the square-shaped single cell C2 and the negative terminal NT3 of the square-shaped single cell C3, which are arranged adjacent to each other, are electrically connected by the plate-shaped bus bar B2 at the other end surface (Y-axis positive direction side end surface) of the single cell stack CS1. Similarly, the positive terminal PT4 of the square-shaped single cell C4 and the negative terminal NT5 of the square-shaped single cell C5, which are arranged adjacent to each other, are electrically connected by the plate-shaped bus bar B4. Figure 3 Figure 3 As shown in FIG. 2, the positive terminal PT2 of the square-shaped single cell C2 and the negative terminal NT3 of the square-shaped single cell C3, which are arranged adjacent to each other, are electrically connected by the plate-shaped bus bar B2 at the other end surface (Y-axis positive direction side end surface) of the single cell stack CS1. Similarly, the positive terminal PT4 of the square-shaped single cell C4 and the negative terminal NT5 of the square-shaped single cell C5, which are arranged adjacent to each other, are electrically connected by the plate-shaped bus bar B4.

[0050] Details of the end bus bars EB11 and EB12 of the single cell stack CS1 will be described later.

[0051] As shown in FIG. 1, the positive terminal PT1 of the square-shaped single cell CI and the negative terminal NT2 of the square-shaped single cell C2, which are arranged adjacent to each other, are electrically connected by the plate-shaped bus bar Bl at one end surface (Y-axis negative direction side end surface) of the single cell stack CS1. Similarly, the positive terminal PT3 of the square-shaped single cell C3 and the negative terminal NT4 of the square-shaped single cell C4, which are arranged adjacent to each other, are electrically connected by the plate-shaped bus bar B3. Similarly, the positive terminal PT5 of the square-shaped single cell C5 and the negative terminal NT6 of the square-shaped single cell C6, which are arranged adjacent to each other, are electrically connected by the plate-shaped bus bar B5. Figure 1 Figure 4 As shown in FIG. 2, the positive terminal PT2 of the square-shaped single cell C2 and the negative terminal NT3 of the square-shaped single cell C3, which are arranged adjacent to each other, are electrically connected by the plate-shaped bus bar B2 at the other end surface (Y-axis positive direction side end surface) of the single cell stack CS1. Similarly, the positive terminal PT4 of the square-shaped single cell C4 and the negative terminal NT5 of the square-shaped single cell C5, which are arranged adjacent to each other, are electrically connected by the plate-shaped bus bar B4.

[0052] As shown in FIG. 2, the positive terminal PT2 of the square-shaped single cell C2 and the negative terminal NT3 of the square-shaped single cell C3, which are arranged adjacent to each other, are electrically connected by the plate-shaped bus bar B2 at the other end surface (Y-axis positive direction side end surface) of the single cell stack CS1. Similarly, the positive terminal PT4 of the square-shaped single cell C4 and the negative terminal NT5 of the square-shaped single cell C5, which are arranged adjacent to each other, are electrically connected by the plate-shaped bus bar B4. Figure 2 ​​​​As shown, at the other end surface (Y-axis positive direction side end surface) of the cell stack CS2, unlike the cell stack CSI, the negative terminal NT1 of the square cell CI arranged adjacent to each other is electrically connected to the positive terminal PT2 of the square cell C2 by the plate-shaped bus bar Bl. Similarly, the negative terminal NT3 of the square cell C3 arranged adjacent to each other is electrically connected to the positive terminal PT4 of the square cell C4 by the plate-shaped bus bar B3. Similarly, the negative terminal NT5 of the square cell C5 arranged adjacent to each other is electrically connected to the positive terminal PT6 of the square cell C6 by the plate-shaped bus bar B5.

[0053] As shown, in the cell stack CS2 as well, the square cells CI to C6 are connected in series by the bus bars Bl to B5. Figure 1 Figure 2 As shown, in the cell stack CS2 as well, the square cells CI to C6 are connected in series by the bus bars Bl to B5.

[0054] As shown, in the cell stack CS2 as well, the square cells CI to C6 are connected in series by the bus bars Bl to B5. Figure 4 As shown, in the cell stack CS2 as well, the square cells CI to C6 are connected in series by the bus bars Bl to B5. Figure 4 As shown, in the cell stack CS2 as well, the square cells CI to C6 are connected in series by the bus bars Bl to B5.

[0055] Details of the bus bars Bl to B5 of the cell stack CS2 will be described later.

[0056] Figure 1 Figure 2 As shown, in the cell stack CS2 as well, the square cells CI to C6 are connected in series by the bus bars Bl to B5.

[0057] As shown, in the cell stack CS2 as well, the square cells CI to C6 are connected in series by the bus bars Bl to B5. Figure 1 Figure 2 As shown, in the cell stack CS2 as well, the square cells CI to C6 are connected in series by the bus bars Bl to B5.

[0058] As shown, in the cell stack CS2 as well, the square cells CI to C6 are connected in series by the bus bars Bl to B5. Figure 1 Figure 2 As shown, in the cell stack CS2 as well, the square cells CI to C6 are connected in series by the bus bars Bl to B5.

[0059] ​​​​Although there are no specific restrictions, Figure 1 and Figure 2 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 and Figure 2 The welded sections WP1 and WP2 before welding are shown. Figure 1 and Figure 2 The welded areas WP1 and WP2 shown have undergone countersinking, resulting in a thinner plate compared to other areas. Additionally, Figure 1 and Figure 3 The welded parts WP1 and WP2 shown have a circular shape when viewed in the XZ plane, and have a through hole in the center.

[0060] Although there are no particular restrictions on the welding method, for example in Figure 4 In the single-cell stack CS1 shown, busbar B1 is welded to the positive terminal PT1 of the square single cell C1 by irradiating the welding section WP1 from the negative Y-axis direction. Similarly, busbar B1 is welded to the negative terminal NT2 of the square single cell C2 by irradiating the welding section WP2 from the negative Y-axis direction.

[0061] like Figure 3 and Figure 4 As shown, end plate EP1 is disposed at the negative X-axis end of the stacked square single cells C1 to C6. End plate EP2 is disposed at the positive X-axis end of the stacked square single cells C1 to C6. That is, end plates EP1 and EP2 press and bind the stacked square single cells C1 to C6 from both ends along the stacking direction (X-axis direction).

[0062] End plates EP1 and EP2 are made of metal materials such as aluminum.

[0063] like Figure 4 As shown, on the positive Y-axis side end faces of the end plates EP1 and EP2 of the single-cell stack CS1, a support platform SS1 is fixed via a connecting member CM1 and bolts BT1 to support the front ends of the end busbars EB11 and EB12, respectively. More specifically, the root of the connecting member CM1 is fixed to the end plates EP1 and EP2 via bolts BT1, and the support platform SS1 is fixed to the front end of the connecting member CM1.

[0064] On the other hand, such as Figure 3As shown, on the negative Y-axis end faces of the end plates EP1 and EP2 of the single-cell stack CS2, a support platform SS2 is fixed via a connecting member CM2 and bolts BT2 to support the front ends of the end busbars EB21 and EB22, respectively. More specifically, the root of the connecting member CM2 is fixed to the end plates EP1 and EP2 via bolts BT1, and the support platform SS1 is fixed to the front end of the connecting member CM2.

[0065] Here, as Figure 4 As shown, the support platform SS2 is configured to extend outward from the single cell stack CS2, that is, towards the negative X-axis direction compared to end plate EP1 or towards the positive X-axis direction compared to end plate EP2. Therefore, the connecting member CM2 that connects the support platform SS2 to end plates EP1 and EP2 is configured to extend outward from end plates EP1 and EP2 along the X-axis direction.

[0066] Here, Figure 3 The single-cell stack CS1 shown has end busbars EB11, EB12 and... Figure 4 The single-cell stack CS2 shown has end busbars EB21 and EB22 with different shapes.

[0067] Furthermore, the battery in this embodiment can have multiple single-cell stacks, not limited to two. For example, the battery in this embodiment can also have multiple pairs of single-cell stacks CS1 and CS2.

[0068] <Detailed Composition of Terminal Busbar>

[0069] Next, refer to Figure 3 and Figure 4 The detailed configuration of the end busbars (first end busbars) EB11 and EB12 of the single battery stack CS1 and the end busbars (second end busbars) EB21 and EB22 of the single battery stack CS2 are explained.

[0070] In addition, although Figure 1 and Figure 2 This is a side view, but for ease of understanding, the end busbars EB11 and EB12 of single cell stack CS1 and the end busbars EB21 and EB22 of single cell stack CS2 are shown with dotted shading.

[0071] Compared to Figure 3 and Figure 4 The busbars B1 to B5 shown refer to the busbars that connect the square single cells C1 to C6 to each other. Figure 3 The end busbars EB11 and EB12 shown are used to connect the single cell stack CS1 to the outside. Similarly, Figure 3 The end busbars EB21 and EB22 shown are used to connect the single cell stack CS2 to the outside.

[0072] The end bus bars EB11, EB12, EB21, EB22 are each a plate-shaped member composed of a metal material such as copper having excellent electrical conductivity, like the bus bars B1 to B5.

[0073] First, the configuration of the single cell stack CS1 will be described with reference to Figure 3 to the end bus bars EB11, EB12 of the single cell stack CS1. As described above, Figure 5 a side surface of the single cell stack CS1 on the side opposite to the single cell stack CS2 is shown. That is, the end bus bars EB11, EB12 are provided on the side surface on the side opposite to the single cell stack CS2 in the single cell stack CS1.

[0074] As shown in Figure 6 , the root of the end bus bar EB11 is fixed to the terminal, i.e., the negative terminal NT1 of the square cell C1 located at the position closest to the first end side (X-axis negative direction side) in the single cell stack (first single cell stack) CS1. The method of fixation is not particularly limited, but is, for example, welding.

[0075] The end bus bar EB11 is extended upward (Z-axis positive direction side) compared to the negative terminal NT1, and is bent toward the Y-axis positive direction side in a manner that the main surface is parallel to the XY plane at a position lower than the upper surface of the square cell C1. Further, the front end portion of the end bus bar EB11, which is extended toward the end plate EP1 side (X-axis negative direction side), is placed on a support stand (first support stand) SS1 fixed to the end plate EP1.

[0076] Further, the first end side of the single cell stack CS1 can be set as the X-axis positive direction side, and the second end side can be set as the X-axis negative direction side.

[0077] Here, Figure 5 is a schematic side view showing the positional relationship between the end bus bar EB11 of the single cell stack CS1 on the first end side and the end bus bar EB21 of the single cell stack CS2. Figure 6 is a schematic plan view showing the positional relationship between the end bus bar EB11 of the single cell stack CS1 on the first end side and the end bus bar EB21 of the single cell stack CS2.

[0078] In Figure 3 , the end bus bar EB11 and the like constituting the single cell stack CS1 are shown by a double-dot chain line.

[0079] As shown in Figure 6 , the support surface of the support stand SS1 is, for example, rectangular in shape when viewed in the XY plane. As shown in Figure 3 and Figure 3As shown, a stud (screw) ST1 extending along the Z-axis is provided at the center of the support surface of the support platform SS1. Furthermore, the stud ST1 provided on the support platform SS1 is inserted into a through hole provided at the front end of the end manifold EB11 placed on the support platform SS1.

[0080] like Figure 4 As shown, the end busbar EB12 has a shape that is mirror-symmetrical to the end busbar EB11 with respect to the YZ plane. Specifically, as... Figure 4 As shown, the root of the end bus bar EB12 is fixed to the positive terminal PT6 of the square single cell C6 located at the second end side (positive X-axis direction side) in the single cell stack CS1.

[0081] The end busbar EB12 extends upward (towards the positive Z-axis) compared to the positive terminal PT6, and bends towards the positive Y-axis with its main surface parallel to the XY plane, slightly below the upper surface of the square single cell C6. Furthermore, the front end of the end busbar EB12, extending towards the end plate EP2 (towards the positive X-axis), is mounted on a support SS1 fixed to the end plate EP2.

[0082] Here, the support platform SS1 fixed to the end plate EP2 has the same shape as the support platform SS1 fixed to the end plate EP1, and is in a mirror-symmetrical arrangement with respect to the YZ plane. Similar to the end busbar EB11, a stud ST1 provided on the support platform SS1 is inserted into the through hole provided at the front end of the end busbar EB12 mounted on the support platform SS1.

[0083] Next, refer to Figure 4 The end busbars EB21 and EB22 of the single-cell stack CS2 will be described. As mentioned above, Figure 4 The side of the single-cell stack CS2 opposite to the single-cell stack CS1 is shown. That is, the end busbars EB21 and EB22 are disposed in the single-cell stack CS2 on the side opposite to the single-cell stack CS1.

[0084] like Figure 3 As shown, the root of the end busbar EB21 is fixed to the positive terminal PT1 of the square single cell C1 located at the first end side (negative X-axis direction side) in the single cell stack (second single cell stack) CS2. The end busbar EB21 bends towards the negative Y-axis direction at the lower side (negative Z-axis direction side) of the positive terminal PT1, with its main surface parallel to the XY plane. Furthermore, the front end of the end busbar EB21, extending towards the end plate EP1 side (negative X-axis direction side), rests on a support platform (second support platform) SS2 fixed to the end plate EP1.

[0085] Here, asFigure 6 The support stand SS2 is provided so as to project to the outside of the cell stack CS2, that is, to the negative direction side of the X axis, compared to the end plate EP1. Thus, the connecting member CM2 that links the support stand SS2 to the end plate EP1 is provided so as to extend from the end plate EP1 to the negative direction side of the X axis. In contrast to this, Figure 4 The support stand SS1 is provided on the inner side of the cell stack CS1, that is, the end plate EP1.

[0086] As shown in FIG. 1, the support stand SS2 has a rectangular shape in plan view, for example. As shown in FIG. 2, the support stand SS2 has a rectangular shape in plan view, for example. Figure 6 As shown in FIG. 1, the support surface of the support stand SS2 also has a rectangular shape in plan view, for example. As shown in FIG. 2, the support surface of the support stand SS2 also has a rectangular shape in plan view, for example. Figure 4 As shown in FIG. 1, the support surface of the support stand SS2 also has a rectangular shape in plan view, for example. As shown in FIG. 2, the support surface of the support stand SS2 also has a rectangular shape in plan view, for example. Figure 4 As shown in FIG. 1, a stud ST2 that extends in the Z axis direction is provided in the central portion of the support surface of the support stand SS2. Also, the stud ST2 provided in the support stand SS2 is inserted into the through hole provided in the front end portion of the end bus bar EB21 placed on the support stand SS2.

[0087] As shown in FIG. 1, the end bus bar EB22 has a shape that is mirror-symmetrical to the end bus bar EB21 with respect to the YZ plane. Specifically, as shown in FIG. 2, the end bus bar EB22 has a shape that is mirror-symmetrical to the end bus bar EB21 with respect to the YZ plane. Figure 4 As shown in FIG. 1, the end bus bar EB22 has a shape that is mirror-symmetrical to the end bus bar EB21 with respect to the YZ plane. Specifically, as shown in FIG. 2, the end bus bar EB22 has a shape that is mirror-symmetrical to the end bus bar EB21 with respect to the YZ plane. Figure 5 As shown in FIG. 1, the end bus bar EB22 has a shape that is mirror-symmetrical to the end bus bar EB21 with respect to the YZ plane. Specifically, as shown in FIG. 2, the end bus bar EB22 has a shape that is mirror-symmetrical to the end bus bar EB21 with respect to the YZ plane.

[0088] Here, the support stand SS2 fixed to the end plate EP2 has the same shape as the support stand SS2 fixed to the end plate EP1, and is in a mirror-symmetrical arrangement with respect to the YZ plane to the support stand SS2 fixed to the end plate EP1.

[0089] Specifically, as shown in FIG. 1, the support stand SS2 fixed to the end plate EP2 is provided so as to project to the outside of the cell stack CS2, that is, to the positive direction side of the X axis, compared to the end plate EP2. Thus, the connecting member CM2 that links the support stand SS2 to the end plate EP2 is provided so as to extend from the end plate EP2 to the positive direction side of the X axis. Also, as with the end bus bar EB21, the stud ST2 provided in the support stand SS2 is inserted into the through hole provided in the front end portion of the end bus bar EB22 placed on the support stand SS2. Figure 6

[0090] <Arrangement between the end bus bar EB11 on the first end side and the end bus bar EB21>

[0091] Here, reference is made to FIGS. 1 and 2.​Figure 5 and Figure 6 The positional relationship between the end bus bar EB11 of the first cell stack CS1 and the end bus bar EB21 of the second cell stack CS2 on the first end side (the negative direction side of the X-axis) will be described.

[0092] As shown in FIG. 1, the front end portion of the end bus bar EB21 is arranged offset to the lower side and the first end side (the negative direction side of the X-axis) with respect to the front end portion of the end bus bar EB11. In addition, as shown in FIG. 1, the front end portion of the end bus bar EB11 and the front end portion of the end bus bar EB21 are arranged in the stacking direction of the square cells C1 to C6. Thus, the opposed end bus bars EB11 and EB21 do not interfere with each other, and the increase in the interval between the arranged cell stacks CS1 and CS2 can be suppressed. Figure 5 Figure 6

[0093] Here, as shown in FIG. 1 and FIG. 2, the front end portion of the end bus bar EB11 is placed on the support stand SS1 fixed to the end plate EP1 of the cell stack CS1. In addition, the front end portion of the end bus bar EB21 is placed on the support stand SS2 fixed to the end plate EP1 of the cell stack CS2. The positions of the front end portions of the end bus bars EB11 and EB21 can be stabilized by the support stands SS1 and SS2. Figure 5 Figure 6

[0094] Further, the support stands SS1 and SS2 are not essential.

[0095] As described above, the stud ST1 provided to the support stand SS1 is inserted into the through hole provided to the front end portion of the end bus bar EB11. In addition, the stud ST2 provided to the support stand SS2 is inserted into the through hole provided to the front end portion of the end bus bar EB21. According to such a structure, the positions of the front end portions of the end bus bars EB11 and EB21 can be more stabilized.

[0096] Further, as shown in FIG. 1 and FIG. 2, the end plate EP1 of the cell stack CS1 and the end plate EP1 of the cell stack CS2 are arranged offset in the stacking direction (the direction of the X-axis). In the illustrated example, the end plate EP1 of the cell stack CS1 is arranged offset to the positive direction side of the X-axis with respect to the end plate EP1 of the cell stack CS2. Figure 7 Figure 7 According to such a structure, the bolt BT1 that fixes the support stand SS1 to the end plate EP1 and the bolt BT2 that fixes the support stand SS2 to the end plate EP1 do not interfere with each other, and the increase in the interval between the arranged cell stacks CS1 and CS2 can be suppressed.

[0097] According to such a structure, the bolt BT1 that fixes the support stand SS1 to the end plate EP1 and the bolt BT2 that fixes the support stand SS2 to the end plate EP1 do not interfere with each other, and the increase in the interval between the arranged cell stacks CS1 and CS2 can be suppressed.

[0098] ​​​​​Further, the end plates EP1 of the cell stacks CS1, CS2 can also be arranged so as not to be staggered in the stacking direction with respect to each other.

[0099] <Arrangement relationship between the end bus bars EB12 and EB22 on the second end side>

[0100] Next, with reference to Figure 7 , the arrangement relationship between the end bus bar EB11 of the cell stack CS1 and the end bus bar EB21 of the cell stack CS2 on the second end side (X-axis positive direction side) will be described. Figure 5 is a schematic side view showing the arrangement relationship between the end bus bar EB12 of the cell stack CS1 and the end bus bar EB22 of the cell stack CS2 on the second end side.

[0101] As shown in Figure 7 , the front end portion of the end bus bar EB22 is arranged so as to be staggered downward and on the second end side (X-axis positive direction side) with respect to the front end portion of the end bus bar EB12. Further, the front end portion of the end bus bar EB12 and the front end portion of the end bus bar EB22 are arranged in the stacking direction of the square cells C1 to C6. Thus, on the second end side as well, the opposing end bus bars EB12, EB22 do not interfere with each other, and an increase in the spacing between the arranged cell stacks CS1, CS2 can be suppressed.

[0102] Here, as described above, the end plate EP1 of the cell stack CS1 is arranged so as to be staggered on the X-axis positive direction side with respect to the end plate EP1 of the cell stack CS2. Thus, the amount of staggering in the X-axis direction of the front end portions of the end bus bars EB11, EB21 shown in Figure 5 is smaller than the amount of staggering in the X-axis direction of the front end portions of the end bus bars EB12, EB22 shown in Figure 6

[0103] Further, the connection objects of the front end portions of the end bus bars EB11, EB21 shown in Figure 7 and Figure 5 and the front end portions of the end bus bars EB12, EB22 shown in Figure 6 are not illustrated, but are not particularly limited.

[0104] For example, the front end portions of the end bus bars EB11, EB21 shown in Figure 7 and Figure 7 may be connected to each other by other bus bars (not illustrated) or the like, thereby connecting the cell stacks CS1, CS2 in series. In this case, the front end portions of the end bus bars EB12, EB22 shown in Figure 5 are not connected to each other, but are connected to, for example, a power supply object or other cell stacks, which are not illustrated.

[0105] ​On the other hand, other busbars (not shown) can also be used to... Figure 6 The front ends of the shown end busbars EB12 and EB22 are connected to each other, thereby connecting the single-cell stacks CS1 and CS2 in series. In this case, Figure 5 and Figure 6 The front ends of the shown end busbars EB11 and EB21 are not connected to each other, but are connected to, for example, a power supply object or other single battery stack not shown.

[0106] As explained above, in the battery involved in this embodiment, such as ​ As shown, the front end of end busbar EB21 is positioned downwards and offset towards the first end (negative X-axis direction) relative to the front end of end busbar EB11. Additionally, as... ​ As shown, the front ends of end busbar EB11 and end busbar EB21 are arranged in the stacking direction of the square single cells C1 to C6. Therefore, the opposing end busbars EB11 and EB21 will not interfere with each other, and the increase in the spacing between the arranged single cell stacks CS1 and CS2 can be suppressed.

[0107] 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 first cell stack and a second cell stack of rectangular parallelepiped shape, each of which is formed by stacking a plurality of rectangular cells each having a terminal provided at a lengthwise end surface, characterized in that: the first cell stack and the second cell stack are arranged so that first and second ends in the stacking direction correspond to each other, a terminal of a rectangular cell located at a position closest to the first end in the first cell stack has a root portion of a first end bus bar fixed thereto, a terminal of a rectangular cell located at a position closest to the first end in the second cell stack has a root portion of a second end bus bar fixed thereto, a front end portion of the second end bus bar is arranged offset downward and toward the first end with respect to a front end portion of the first end bus bar, and the front end portion of the first end bus bar and the front end portion of the second end bus bar are arranged in the stacking direction of the plurality of rectangular cells.

2. The battery according to claim 1, characterized in that: the front end portion of the first end bus bar is placed on a first support platform fixed at the first end of the first cell stack, and the front end portion of the second end bus bar is placed on a second support platform fixed at the first end of the second cell stack.

3. The battery according to claim 2, characterized in that: a screw provided on the first support platform is inserted through a through hole provided on the front end portion of the first end bus bar, and a screw provided on the second support platform is inserted through a through hole provided on the front end portion of the second end bus bar.

4. The battery according to claim 2 or 3, characterized in that: the first support platform is fixed to an end plate at the first end of the first cell stack, and the second support platform is fixed to an end plate at the first end of the second cell stack.

5. The battery according to claim 4, characterized in that: the first support platform is bolted to the end plate at the first end of the first cell stack, the second support platform is bolted to the end plate at the first end of the second cell stack, and the end plate at the first end of the first cell stack and the end plate at the first end of the second cell stack are arranged offset in the stacking direction. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​

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