Battery

Abstract

A battery includes a first battery cell stack and a second battery cell stack arranged side by side, and a first cooling tube and a second cooling tube provided below the first battery cell stack and the second battery cell stack, respectively, and configured to cool the first battery cell stack and the second battery cell stack, respectively. First and second cooling tubes extend from first ends of the first and second battery cell stacks to second ends thereof, respectively, and are connected to each other at the second ends. An inlet port and an outlet port for a refrigerant to flow through the first cooling pipe and the second cooling pipe are arranged at the first end, and the refrigerant flowing in from the inlet port firstly passes through the first cooling pipe from the first end, then passes through the second cooling pipe from the second end and flows out from the outlet port.

Description

Technical Field

[0001] The present disclosure relates to batteries. Background Art

[0002] In a related art battery, a terminal is provided on the upper surface of each stacked rectangular battery cell. Recently, as disclosed in Patent Document 1, a battery has been developed in which a terminal is provided on the longitudinal end surface of each stacked rectangular battery cell.

[0003] Patent Document 1: U.S. Patent Application Publication No. 2022 / 0302533. Summary of the Invention

[0004] The inventors of this application are developing a battery in which each of a plurality of battery cell stacks arranged side by side is cooled by a corresponding one of a plurality of cooling tubes extending in the longitudinal direction of the battery cell stacks. The inventors have discovered a problem in such a battery: when refrigerant is simply fed from one end of each of the cooling tubes to the other end in parallel with one another, the pressure loss of the refrigerant increases, making it impossible to uniformly cool the battery cell stacks.

[0005] The present disclosure has been made in view of the above circumstances, and provides a battery capable of reducing the pressure loss of a refrigerant flowing therethrough and thereby uniformly cooling a battery cell stack.

[0006] A battery according to one aspect of the present disclosure includes: A first battery cell stack and a second battery cell stack arranged side by side; and First cooling pipes and second cooling pipes are respectively disposed below the first battery cell stack and the second battery cell stack and configured to cool the first battery cell stack and the second battery cell stack, respectively, wherein: The first cooling tube and the second cooling tube extend from first ends of the first battery cell stack and the second battery cell stack to second ends thereof, respectively, and are connected to each other at the second ends. both an inlet port and an outlet port for refrigerant to flow through the first cooling tube and the second cooling tube are provided at the first end, and The refrigerant flowing in from the inlet port first passes through the first cooling tube from the first end, then passes through the second cooling tube from the second end, and flows out from the outlet port.

[0007] In the battery according to the present disclosure, refrigerant flowing in from the inlet port first passes through the first cooling tube from the first end, then passes through the second cooling tube from the second end, and flows out from the outlet port. Therefore, compared to a configuration in which refrigerant flows from the first ends of the first and second cooling tubes in parallel to each other to their second ends, refrigerant pressure loss can be reduced, resulting in more uniform cooling of the battery cell stack.

[0008] In each of the first and second battery cell stacks, multiple rectangular battery cells may be stacked one on top of the other. Terminals may be provided on both longitudinal end faces of each of the multiple rectangular battery cells. A pair of first cooling tubes may be provided at both width ends of the first battery cell stack. And a pair of second cooling tubes may be provided at both width ends of the second battery cell stack. This configuration allows for efficient and uniform cooling of the battery cell stacks.

[0009] Each of the pair of first cooling tubes and the pair of second cooling tubes can be formed to extend from the first end to the second end, from the second end to the first end, and then from the first end to the second end, forming a Z-shape between the first and second ends. Notably, in each of the pair of first cooling tubes, the refrigerant can flow from one end in the width direction of the first battery cell stack toward the center thereof, and in each of the pair of second cooling tubes, the refrigerant can flow from one end in the width direction of the second battery cell stack toward the center thereof. This configuration allows for more uniform cooling of the battery cell stack.

[0010] The battery may include a plurality of first battery cell stacks and a plurality of second battery cell stacks. It is noteworthy that the number of first battery cell stacks and second battery cell stacks may be equal. With the above configuration, the pressure loss of the refrigerant is reduced, so that the battery cell stacks can be cooled efficiently and evenly.

[0011] The battery may further include a case configured to accommodate the first battery cell stack and the second battery cell stack, and the first cooling pipe and the second cooling pipe may be disposed below a bottom plate of the case.

[0012] According to the present disclosure, it is possible to provide a battery capable of reducing the pressure loss of a refrigerant flowing therethrough and thereby uniformly cooling a battery cell stack. The above and other objects, features and advantages of the present disclosure will be more fully understood from the detailed description and accompanying drawings given below. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 is a schematic cross-sectional view showing a battery according to a first embodiment; Figure 2 is a schematic perspective view showing a battery cell stack CS1 in a battery according to a first embodiment; Figure 3 is a schematic perspective view showing a battery cell stack CS1 in a battery according to a first embodiment; Figure 4 yes Figure 1 An enlarged cross-sectional view of region IV is shown; Figure 5is a schematic plan view showing a planar configuration of cooling pipes CP1 and CP2 according to the first embodiment; Figure 6 is a schematic plan view showing a planar configuration of cooling pipes CP1 and CP2 according to a comparative example. DETAILED DESCRIPTION

[0014] Hereinafter, a specific embodiment of the present disclosure will be described in detail with reference to the drawings. However, the present disclosure is not limited to the following embodiments. Further, for the sake of clarity, the following description and drawings will be appropriately simplified.

[0015] (First embodiment) <Battery Configuration> First, refer to Figures 1 to 4 The structure of the battery according to the first embodiment will be described. Figure 1 is a schematic cross-sectional view showing a battery according to a first embodiment. Figure 2 and Figure 3 Each of them is a schematic perspective view showing a battery cell stack CS1 in the battery according to the first embodiment. Figure 4 yes Figure 1 An enlarged cross-sectional view of region IV is shown.

[0016] The battery according to this embodiment is used as, for example, an on-vehicle battery. Vehicles equipped with the battery according to this embodiment are not limited to any particular vehicle. For example, the vehicle may be an electric vehicle, a hybrid vehicle, a fuel cell vehicle, or the like that can be driven by electricity supplied from the battery. It is worth noting that, undoubtedly, Figures 1 to 4 The right-handed XYZ rectangular coordinate system shown in each of the other figures is shown for convenience in order to explain the positional relationship between the components. Figure 1 In general, the positive direction on the Z axis is the vertical upward direction, and the XY plane is parallel to the horizontal plane.

[0017] like Figure 1 As shown, the battery according to the first embodiment includes battery cell stacks CS1 and CS2, an upper case UC, a lower case LC, and cooling pipes CP1 and CP2. Figure 1 As shown, the cooling pipe CP1 includes a pair of cooling pipes CP11 and CP12, and the cooling pipe CP2 includes a pair of cooling pipes CP21 and CP22.

[0018] exist Figure 1 , the battery cell stacks CS1 and CS2 extend in the X-axis direction. Figure 1 As shown, the battery cell stacks CS1 and CS2 are arranged side by side in the Y-axis direction inside the case (ie, between the upper case UC and the lower case LC). It is worth noting that Figure 1 , a side view, not a cross-sectional view, of the battery cell stacks CS1 and CS2 is shown.

[0019] Note that since the battery cell stacks CS1 and CS2 have similar configurations to each other, reference will be made to Figures 2 to 4 To describe the configuration of the battery cell stack CS1. Figure 2 and Figure 3 As shown, the battery cell stack CS1 includes rectangular battery cells C1 to C6, bus bars B1 to B5, and metal strips MB1 and MB2, and further includes Figure 4 Insulation plates IP1 and IP2 are shown. It is worth noting that Figure 4 , a side view of the rectangular battery cell C1 is shown, not a cross-sectional view.

[0020] like Figure 2 and Figure 3 As shown, rectangular battery cells C1 to C6 are each a rectangular parallelepiped shape extending in the Y-axis direction. Rectangular battery cells C1 to C6 are stacked one on top of another in the thickness direction (X-axis direction) to form a battery cell stack CS1. Each of rectangular battery cells C1 to C6 is, for example, a secondary battery such as a lithium-ion battery or a nickel-metal hydride battery.

[0021] It is worth noting that in Figure 2 and Figure 3 In FIG, the battery cell stack CS1 is shown in a simplified manner. Figure 2 and Figure 3 The illustrated battery cell stack CS1 is formed of six rectangular battery cells C1 to C6, but is typically formed of more rectangular battery cells. In practice, the number of rectangular battery cells forming the battery cell stack CS1 is not limited to any particular number and may be any number greater than two.

[0022] Furthermore, a heat insulating plate, a spacer for adjusting the distance between adjacent rectangular battery cells, or the like (not shown) may be inserted between adjacent rectangular battery cells. Furthermore, end plates (not shown) may be provided at both ends of the battery cell stack CS1 in the stacking direction (X-axis direction).

[0023] like Figure 2 As shown, the rectangular battery cell C1 is provided with a positive terminal PT1 on one end face in the longitudinal direction thereof (the end face on the negative side of the Y axis). Figure 2 The positive terminal PT1 shown has a rectangular shape in the XZ plane view and is provided to protrude outward from the end surface of the rectangular battery cell C1. However, the present disclosure is not particularly limited thereto. Further, a positive terminal PT1 is provided on the upper side (positive side of the Z axis) of the end surface of the rectangular battery cell C1. Figure 2 The positive terminal PT1 is shown. The positive terminal PT1 is made of, for example, a metal material having excellent electrical conductivity such as copper.

[0024] Similarly, if Figure 2 As shown, the rectangular battery cell C2 adjacent to the rectangular battery cell C1 is provided with a negative terminal NT2 on one end face in the longitudinal direction (the end face on the negative side of the Y axis). The rectangular battery cell C3 adjacent to the rectangular battery cell C2 is provided with a positive terminal PT3 on one end face in the longitudinal direction (the end face on the negative side of the Y axis). The rectangular battery cell C4 adjacent to the rectangular battery cell C3 is provided with a negative terminal NT4 on one end face in the longitudinal direction (the end face on the negative side of the Y axis). The rectangular battery cell C5 adjacent to the rectangular battery cell C4 is provided with a positive terminal PT5 on one end face in the longitudinal direction (the end face on the negative side of the Y axis). The rectangular battery cell C6 adjacent to the rectangular battery cell C5 is provided with a negative terminal NT6 on one end face in the longitudinal direction (the end face on the negative side of the Y axis).

[0025] like Figure 2 As shown, each of the negative terminal NT2 of the rectangular battery cell C2, the positive terminal PT3 of the rectangular battery cell C3, the negative terminal NT4 of the rectangular battery cell C4, the positive terminal PT5 of the rectangular battery cell C5, and the negative terminal NT6 of the rectangular battery cell C6 has a shape similar to the positive terminal PT1 of the rectangular battery cell C1 and is arranged in a manner similar to the manner in which the positive terminal PT1 of the rectangular battery cell C1 is arranged.

[0026] Furthermore, if Figure 2 As shown, the positive terminal PT1 of the rectangular battery cell C1 and the negative terminal NT2 of the rectangular battery cell C2, which are arranged adjacent to each other, are electrically connected to each other via a plate-shaped bus bar B1. Similarly, the positive terminal PT3 of the rectangular battery cell C3 and the negative terminal NT4 of the rectangular battery cell C4, which are arranged adjacent to each other, are electrically connected to each other via a plate-shaped bus bar B3. Similarly, the positive terminal PT5 of the rectangular battery cell C5 and the negative terminal NT6 of the rectangular battery cell C6, which are arranged adjacent to each other, are electrically connected to each other via a plate-shaped bus bar B5.

[0027] On the other hand, Figure 3 As shown, the rectangular battery cell C1 is provided with a negative terminal NT1 on the other end face in the longitudinal direction thereof (the end face on the positive side of the Y axis). Figure 2 As shown in the positive terminal PT1, Figure 3 The negative terminal NT1 shown has a rectangular shape in the XZ plane view and is provided to protrude outward from the end surface of the rectangular battery cell C1. However, the present disclosure is not particularly limited thereto. Further, as Figure 2As shown in the figure, the positive terminal PT1 is provided on the upper side (Z-axis positive side) of the end face of the rectangular battery cell C1. Figure 3 The negative terminal NT1 is shown. Like the positive terminal PT1, the negative terminal NT1 is made of a metal material having excellent electrical conductivity such as copper.

[0028] Similarly, if Figure 3 As shown, the rectangular battery cell C2 adjacent to the rectangular battery cell C1 is provided with a positive terminal PT2 on its other end face in the longitudinal direction (the end face on the positive side of the Y axis). The rectangular battery cell C3 adjacent to the rectangular battery cell C2 is provided with a negative terminal NT3 on its other end face in the longitudinal direction (the end face on the positive side of the Y axis). The rectangular battery cell C4 adjacent to the rectangular battery cell C3 is provided with a positive terminal PT4 on its other end face in the longitudinal direction (the end face on the positive side of the Y axis). The rectangular battery cell C5 adjacent to the rectangular battery cell C4 is provided with a negative terminal NT5 on its other end face in the longitudinal direction (the end face on the positive side of the Y axis). The rectangular battery cell C6 adjacent to the rectangular battery cell C5 is provided with a positive terminal PT6 on its other end face in the longitudinal direction (the end face on the positive side of the Y axis).

[0029] like Figure 3 As shown, each of the positive terminal PT2 of the rectangular battery cell C2, the negative terminal NT3 of the rectangular battery cell C3, the positive terminal PT4 of the rectangular battery cell C4, the negative terminal NT5 of the rectangular battery cell C5, and the positive terminal PT6 of the rectangular battery cell C6 has a shape similar to the negative terminal NT1 of the rectangular battery cell C1 and is arranged in a manner similar to the manner in which the negative terminal NT1 of the rectangular battery cell C1 is arranged.

[0030] Furthermore, if Figure 3 As shown, the positive terminal PT2 of the rectangular battery cell C2 and the negative terminal NT3 of the rectangular battery cell C3, which are arranged adjacent to each other, are electrically connected to each other through the plate bus bar B2. Similarly, the positive terminal PT4 of the rectangular battery cell C4 and the negative terminal NT5 of the rectangular battery cell C5, which are arranged adjacent to each other, are electrically connected to each other through the plate bus bar B4. As described above, Figure 2 and Figure 3 In the illustrated battery cell stack CS1 , rectangular battery cells C1 to C6 are connected in series with one another via bus bars B1 to B5 .

[0031] It is worth noting that Figure 3 The negative terminal NT1 of the rectangular battery cell C1 shown is connected to the positive terminal of another battery cell stack through, for example, a bus bar (not shown). However, the present disclosure is not particularly limited thereto. Further, Figure 3The positive terminal PT6 of the rectangular battery cell C6 is connected to the negative terminal of another battery cell stack via, for example, a bus bar (not shown). However, the present disclosure is not particularly limited thereto. With the above structure, for example, multiple battery cell stacks can be connected in series.

[0032] because Figure 2 and Figure 3 The illustrated bus bars B1 to B5 have similar structures to one another, and thus the bus bar B1 will be described. like Figure 2 As shown, the bus bar B1 is a plate-shaped member that electrically connects the positive terminal PT1 of the rectangular battery cell C1 and the negative terminal NT2 of the rectangular battery cell C2 disposed adjacent to each other. The bus bar B1 is made of, for example, a metal material having excellent electrical conductivity such as copper.

[0033] like Figure 2 As shown, busbar B1 is, for example, a plate-like member having a rectangular shape in an XZ plane view. Busbar B1 is provided to substantially cover the entire positive terminal PT1 of rectangular battery cell C1 and the entire negative terminal NT2 of rectangular battery cell C2. Busbar B1 includes a pair of welded portions WP1 and WP2, respectively welded to the positive terminal PT1 of rectangular battery cell C1 and the negative terminal NT2 of rectangular battery cell C2, which are arranged adjacent to each other.

[0034] The bus bar B1 is provided with two adjacent ends in the X-axis direction at its lower portion (ie, the portion on the negative side of the Z-axis). Figure 2 However, the positions of the welding parts WP1 and WP2 are not limited to specific places. Figure 2 Welded portions WP1 and WP2 before welding are shown. Figure 2 The welded portions WP1 and WP2 are shown to be countersunk so that the area of ​​the busbar where the welded portions WP1 and WP2 are provided is thinner than the rest of the busbar (ie, the surrounding area thereof). Figure 2 Each of the illustrated welding portions WP1 and WP2 has a circular shape in an XZ plane view, and a through hole is formed in the center thereof.

[0035] The welding method is not limited to any particular method. For example, a laser beam is applied to weld portion WP1 from its negative Y-axis side to weld bus bar B1 to the positive terminal PT1 of rectangular battery cell C1 at weld portion WP1. Similarly, a laser beam is applied to weld portion WP2 from its negative Y-axis side to weld bus bar B1 to the negative terminal NT2 of rectangular battery cell C2 at weld portion WP2.

[0036] like Figure 2 and Figure 3As shown, each of the metal bands MB1 and MB2 is a metal member having an L-shape in YZ cross-section and extending over the entire length of the battery cell stack CS1 in the stacking direction. The metal bands MB1 and MB2 restrain (i.e., hold) both lower ends in the longitudinal direction of the rectangular battery cells C1 to C6 (i.e., the battery cell stack CS1). It is worth noting that the metal strips MB1 and MB2 may also be divided into multiple sections, and the multiple sections are arranged over the entire length of the battery cell stack CS1.

[0037] More specifically, if Figure 4 As shown, the metal strip MB1 is provided in an L-shape in the YZ cross section along the lower corners on the Y-axis negative side of the rectangular battery cells C1 to C6, and includes a bottom plate that supports the bottom surfaces of the rectangular battery cells C1 to C6 and side plates that support the end surfaces of the rectangular battery cells C1 to C6. Similarly, the metal strip MB2 is provided in an L-shape in the YZ cross section along the lower corners on the Y-axis positive side of the rectangular battery cells C1 to C6, and includes a bottom plate that supports the bottom surfaces of the rectangular battery cells C1 to C6 and side plates that support the end surfaces of the rectangular battery cells C1 to C6.

[0038] like Figure 4 As shown, insulating plate IP1 is provided between rectangular battery cells C1 to C6 and metal strip MB1 at the lower corners of each of the rectangular battery cells C1 to C6 on the negative Y-axis side, electrically insulating the rectangular battery cells C1 to C6 from metal strip MB1. In other words, insulating plate IP1 is an insulating member having an L-shape in a YZ cross-section and extending over the entire length of battery cell stack CS1 in the stacking direction.

[0039] Similarly, insulating plate IP2 is provided between the rectangular battery cells C1 to C6 and the metal strip MB2 at their respective lower corners on the positive Y-axis side, electrically insulating the rectangular battery cells C1 to C6 from the metal strip MB2. That is, insulating plate IP2 is an insulating member having an L-shape in a YZ cross section and extending over the entire length of battery cell stack CS1 in the stacking direction.

[0040] The insulating plates IP1 and IP2 are made of, for example, resin. Figure 4 The insulating plates IP1 and IP2 are shown as having an L-shape in a YZ cross section, corresponding to the shape of the metal strips MB1 and MB2, respectively, and are slightly larger than the metal strips MB1 and MB2, respectively, and are arranged to protrude from the metal strips MB1 and MB2, respectively. However, the shape and size of the insulating plates IP1 and IP2 are not limited to any specific shape and size. It is noteworthy that the insulating plates IP1 and IP2 are not indispensable as long as the rectangular battery cells C1 to C6 and the metal strips MB1 and MB2 can be electrically insulated from each other.

[0041] Again by reference Figure 1 Continue with the description. like Figure 1 As shown, the upper case UC and the lower case LC form a housing for accommodating battery cell stacks CS1 and CS2. The upper case UC is a metal plate that covers the upper surfaces of the battery cell stacks CS1 and CS2, while the lower case LC is a metal plate that supports the bottom surfaces of the battery cell stacks CS1 and CS2. The bottom surfaces of the battery cell stacks CS1 and CS2 (i.e., the rectangular battery cells C1 to C6) are electrically insulated from the upper surface of the lower case LC by, for example, an insulating, thermally conductive layer (not shown).

[0042] like Figure 1 As shown, the cooling pipe (first cooling pipe) CP1 cools the battery cell stack (first battery cell stack) CS1. The cooling pipe (second cooling pipe) CP2 cools the battery cell stack (second battery cell stack) CS2. Figure 1 As shown, the cooling pipes CP1 and CP2 extend over the entire length of the battery cell stacks CS1 and CS2 in the stacking direction (X-axis direction) while being in contact with the bottom surface of the lower case LC. It is noteworthy that as long as the battery cell stacks CS1 and CS2 can be cooled from below by the cooling pipes CP1 and CP2 respectively, the cooling pipes CP1 and CP2 may be provided above the bottom surface of the lower case LC, that is, inside the case.

[0043] The refrigerant flowing through the cooling pipes CP1 and CP2 is, for example, water. As will be described in detail later, the refrigerant flows through Figure 1 The inlet and outlet ports of the cooling pipes CP1 and CP2 are both provided on the first end sides (end sides on the negative side of the X axis) of the battery cell stacks CS1 and CS2. Furthermore, the cooling pipes CP1 and CP2 are connected to each other on the second end sides (end sides on the positive side of the X axis) of the battery cell stacks CS1 and CS2.

[0044] Furthermore, the refrigerant flowing in from the inlet port provided at the first end first passes through the cooling pipe CP1 from the first end, then passes through the cooling pipe CP2 from the second end, and flows out from the outlet port provided at the first end. As will be described in detail later, compared with a configuration in which the refrigerant flows parallel to each other from the first ends of the cooling pipes CP1 and CP2 to their second ends, the battery according to this embodiment can further reduce the pressure loss of the refrigerant, thereby cooling the battery cell stacks CS1 and CS2 more evenly.

[0045] <Detailed configuration of cooling pipes CP1 and CP2> The detailed configuration of the cooling pipes CP1 and CP2 will be described below. like Figure 1As shown, cooling pipe CP1 includes a pair of cooling pipes CP11 and CP12 provided at both ends of battery cell stack CS1 in the width direction. Similarly, cooling pipe CP2 includes a pair of cooling pipes CP21 and CP22 provided at both ends of battery cell stack CS2 in the width direction.

[0046] Figure 1 Each of the pair of cooling pipes CP11 and CP12 and the pair of cooling pipes CP21 and CP22 shown is formed by bonding two metal plates, each having projections and grooves. However, the structure of the cooling pipes is not limited to any particular one. For example, metal plates made of aluminum, aluminum alloys, copper, copper alloys, etc., which have excellent thermal conductivity, can be used. When the battery is used as an in-vehicle battery, for example, plates made of aluminum alloy are preferably used to reduce weight.

[0047] It is worth noting that Figure 4 As shown, since terminals ( Figure 4 Because the positive and negative terminals PT1 and NT1 are located in the battery cell stack, they are likely to generate heat when current flows through them. To combat this heat, a pair of cooling pipes CP11 and CP12 are provided at both ends of the battery cell stack CS1 in the width direction, enabling efficient and uniform cooling of the battery cell stack CS1. Similarly, a pair of cooling pipes CP21 and CP22 are provided at both ends of the battery cell stack CS2 in the width direction, enabling efficient and uniform cooling of the battery cell stack CS2.

[0048] Figure 1 and Figure 4 The illustrated cooling pipe CP11 includes three cooling pipes CP11a, CP11b, and CP11c extending in the X-axis direction, but the number of cooling pipes is not limited to three. The three cooling pipes CP11a, CP11b, and CP11c are arranged side by side in this order from the Y-axis negative end toward the center of the battery cell stack CS1 (i.e., the rectangular battery cells C1 to C6).

[0049] Similarly, Figure 1 and Figure 4 The cooling pipe CP12 shown includes three cooling pipes CP12a, CP12b and CP12c extending in the X-axis direction. The three cooling pipes CP12a, CP12b and CP12c are arranged side by side in this order from the Y-axis positive end of the battery cell stack CS1 (i.e., rectangular battery cells C1 to C6) toward its center.

[0050] It is worth noting that Figure 1 and Figure 4As shown, the cross-sectional shape of each of the cooling pipes CP11a, CP11b, and CP11c is a parallelogram or trapezoid, that is, a rectangle. Therefore, the contact area between cooling pipe CP11 and the lower case LC is large, enabling efficient cooling of battery cell stack CS1. Similarly, the cross-sectional shape of each of the cooling pipes CP12a, CP12b, and CP12c is a parallelogram or trapezoid, that is, a rectangle. Therefore, the contact area between cooling pipe CP12 and the lower case LC is large, enabling efficient cooling of battery cell stack CS1.

[0051] Figure 1 The illustrated cooling pipes CP21 include three cooling pipes CP21a, CP21b, and CP21c extending in the X-axis direction, but the number of cooling pipes is not limited to three. The three cooling pipes CP21a, CP21b, and CP21c are arranged side by side in this order from the Y-axis negative end of the battery cell stack CS2 (i.e., the rectangular battery cells C1 to C6) toward the center thereof.

[0052] Similarly, Figure 1 The cooling pipe CP22 shown includes three cooling pipes CP22a, CP22b and CP22c extending in the X-axis direction. The three cooling pipes CP22a, CP22b and CP22c are arranged side by side in this order from the Y-axis positive end of the battery cell stack CS2 (i.e., the rectangular battery cells C1 to C6) toward its center.

[0053] It is worth noting that Figure 1 As shown, the cross-sectional shape of each of the cooling pipes CP21a, CP21b, and CP21c is a parallelogram or trapezoid, that is, a rectangle. Therefore, the contact area between the cooling pipe CP21 and the lower case LC is large, enabling efficient cooling of the battery cell stack CS2. Similarly, the cross-sectional shape of each of the cooling pipes CP22a, CP22b, and CP22c is a parallelogram or trapezoid, that is, a rectangle. Therefore, the contact area between the cooling pipe CP22 and the lower case LC is large, enabling efficient cooling of the battery cell stack CS1.

[0054] <Plane Configuration of Cooling Pipes CP1 and CP2> Next, we will refer to Figure 5 The planar arrangement of the cooling pipes CP1 and CP2 will be described. Figure 5 : is a schematic plan view showing the planar configuration of the cooling pipes CP1 and CP2 according to the first embodiment. That is, Figure 5 The piping paths of the cooling pipes CP1 and CP2 are shown. Figure 5 , the battery cell stacks CS1 and CS2 are shown by double-dashed lines. Figure 5 Arrows shown in the middle cooling pipes CP1 and CP2 indicate the flow of the refrigerant. It is worth noting that although Figure 5 It is a plan view, but for easier understanding, the cooling pipes CP1 and CP2 are represented by dots.

[0055] like Figure 5 As shown, both the inlet port IN and the outlet port OUT for the refrigerant to flow through the cooling pipes CP1 and CP2 are provided at the first ends (negative ends of the X-axis) of the battery cell stacks CS1 and CS2. Furthermore, the cooling pipes CP1 and CP2 are connected to each other at the second ends (positive ends of the X-axis) of the battery cell stacks CS1 and CS2.

[0056] Further, such as Figure 5 As shown, the refrigerant flowing in from the inlet port IN first passes through the cooling pipes CP11 and CP12 (cooling pipe CP1) from the first end, then passes through the cooling pipes CP21 and CP22 (cooling pipe CP2) from the second end, and flows out from the outlet port OUT.

[0057] That is, the cooling pipe CP1 for cooling the battery cell stack CS1 and the cooling pipe CP2 for cooling the battery cell stack CS2 are connected to each other in series so as to first cool the battery cell stack CS1 and then cool the battery cell stack CS2. It is noteworthy that the cooling pipes CP11 and CP12 constituting the cooling pipe CP1 are connected in parallel to each other between the first end and the second end. Similarly, the cooling pipes CP21 and CP22 constituting the cooling pipe CP2 are connected in parallel to each other between the first end and the second end.

[0058] More specifically, if Figure 5 As shown, the cooling pipe CP11 for cooling the battery cell stack CS1 includes Figure 1 and Figure 4 The cooling pipes CP11a, CP11b, and CP11c shown extend from a first end to a second end, then from the second end to the first end, and then from the first end to the second end, forming a Z-shape between the first and second ends. In other words, cooling pipe CP11 includes two U-shaped folded portions. It is worth noting that the Z-shape can also be considered an N-shape.

[0059] like Figure 5 As shown, the refrigerant flowing in from the inlet port flows from the first end and passes through Figure 1 and Figure 4 By flowing the refrigerant through the cooling pipe CP11 from one end in the width direction of the battery cell stack CS1 toward the center thereof, the battery cell stack CS1 can be cooled uniformly and efficiently.

[0060] Similarly, if Figure 5 As shown, the cooling pipe CP12 for cooling the battery cell stack CS1 includes Figure 1 and Figure 4 The cooling pipes CP12a, CP12b, and CP12c are shown and are formed to extend from a first end to a second end, from the second end to the first end, and then from the first end to the second end to form a Z shape between the first end and the second end.

[0061] like Figure 5 As shown, the refrigerant flowing in from the inlet port flows from the first end and passes through Figure 1 and Figure 4 By flowing the refrigerant through the cooling pipe CP12 from one end in the width direction of the battery cell stack CS1 toward the center thereof, the battery cell stack CS1 can be cooled uniformly and efficiently.

[0062] At the same time, if Figure 5 As shown, the cooling pipe CP21 for cooling the battery cell stack CS2 includes Figure 1 The cooling pipes CP21a, CP21b, and CP21c are shown and are formed to extend from the second end to the first end, from the first end to the second end, and then from the second end to the first end to form a Z shape between the first and second ends.

[0063] like Figure 5 As shown, the refrigerant that has passed through the cooling pipes CP11 and CP12 flows from the second end and passes through Figure 1 The cooling pipes CP21a, CP21b, and CP21c are shown, and the refrigerant flows out of the outlet port OUT provided at the first end. By allowing the refrigerant to flow from one end of the battery cell stack CS2 in the width direction toward the center thereof in the cooling pipe CP21 as described above, the battery cell stack CS2 can be cooled uniformly and efficiently.

[0064] Similarly, if Figure 5 As shown, the cooling pipe CP22 for cooling the battery cell stack CS2 includes Figure 1 The cooling pipes CP22a, CP22b, and CP22c are shown and are formed to extend from the second end to the first end, from the first end to the second end, and then from the second end to the first end to form a Z shape between the first end and the second end.

[0065] like Figure 5 As shown, the refrigerant that has passed through the cooling pipes CP11 and CP12 flows from the second end and passes through Figure 1The cooling pipes CP22a, CP22b, and CP22c are shown, and the refrigerant flows out of the outlet port OUT provided at the first end. By allowing the refrigerant to flow from one end in the width direction of the battery cell stack CS2 toward the center thereof in the cooling pipes CP22 as described above, the battery cell stack CS2 can be cooled uniformly and efficiently.

[0066] <Plane Configuration of Cooling Pipes CP1 and CP2 According to Comparative Example> Next, we will refer to Figure 6 A description will be given of the planar configuration of the cooling pipes CP1 and CP2 according to the comparative example. Figure 6 : is a schematic plan view showing the planar configuration of the cooling pipes CP1 and CP2 according to the comparative example. That is, Figure 6 FIG. 2 shows the piping paths of the cooling pipes CP1 and CP2 according to the comparative example. Figure 6 , the battery cell stacks CS1 and CS2 are shown by double-dashed lines. Figure 6 Arrows shown in the middle cooling pipes CP1 and CP2 indicate the flow of the refrigerant. It is worth noting that although Figure 6 It is a plan view, but for easier understanding, the cooling pipes CP1 and CP2 are represented by dots.

[0067] like Figure 6 As shown, the inlet port IN and the outlet port OUT for the refrigerant to flow through the cooling pipes CP1 and CP2 are both provided at the center of the negative X-axis direction of the outer side of the battery cell stacks CS1 and CS2 arranged side by side. Furthermore, the cooling pipes CP1 and CP2 are connected to each other at both ends in the longitudinal direction (X-axis direction) of the battery cell stacks CS1 and CS2. It is worth noting that, as Figure 6 As shown, in the cooling pipes CP1 and CP2 according to the comparative example, an additional inflow pipe PI for connecting the inlet port IN to the first end (X-axis negative end) and an additional outflow pipe PO for connecting the output port OUT to the second end (X-axis positive end) are provided.

[0068] It is worth noting that although Figure 6 In the example, the inlet port IN and outlet port OUT provided on the outer sides of the side-by-side battery cell stacks CS1 and CS2 are located on the positive side of the Y axis of battery cell stack CS2, but may also be located on the negative side of the Y axis of battery cell stack CS1. Furthermore, the inlet pipe PI may be omitted, and the outlet pipe PO may be extended to the first end, so that both the inlet port IN and the outlet port OUT are located at the first end. Alternatively, the outlet pipe PO may be omitted, and the inlet pipe PI may be extended to the second end, so that both the inlet port IN and the outlet port OUT are located at the second end.

[0069] like Figure 6As shown, the refrigerant flowing in from the inlet port IN flows in from the first end, passes through the cooling pipes CP11 and CP12 (cooling pipe CP1) and the cooling pipes CP21 and CP22 (cooling pipe CP2), reaches the second end, and flows out from the outlet port OUT. Figure 6 In the illustrated comparative example, the cooling pipe CP1 for cooling the battery cell stack CS1 and the cooling pipe CP2 for cooling the battery cell stack CS2 are connected in parallel to each other, and the battery cell stacks CS1 and CS2 are cooled simultaneously.

[0070] like Figure 6 As shown, the cooling pipe CP11 according to the comparative example also includes Figure 1 and Figure 4 The cooling pipes CP11a, CP11b and CP11c are formed to extend from the first end to the second end, from the second end to the first end, and then from the first end to the second end to form a Z shape between the first end and the second end. Figure 6 As shown, the refrigerant flowing in from the inlet port flows from the first end, passes through the cooling pipes CP11a, CP11b and CP11c in sequence, and reaches the second end.

[0071] Similarly, if Figure 6 As shown, the cooling pipe CP12 according to the comparative example also includes Figure 1 and Figure 4 The cooling pipes CP12a, CP12b and CP12c are shown and are formed to extend from the first end to the second end, from the second end to the first end, and then from the first end to the second end to form a Z shape between the first end and the second end. Figure 6 As shown, the refrigerant flowing in from the inlet port flows from the first end, passes through the cooling pipes CP12a, CP12b and CP12c in sequence, and reaches the second end.

[0072] Similarly, if Figure 6 As shown, the cooling pipe CP21 according to the comparative example also includes Figure 1 The cooling pipes CP21a, CP21b and CP21c are formed to extend from the first end to the second end, from the second end to the first end, and then from the first end to the second end to form a Z shape between the first end and the second end. Figure 6 As shown, in the cooling pipe CP21 according to the comparative example, the refrigerant flowing in from the inlet port flows from the first end, sequentially passes through the cooling pipes CP21a, CP21b, and CP21c, and reaches the second end.

[0073] Similarly, if Figure 6 As shown, the cooling pipe CP22 according to the comparative example also includes Figure 1The cooling pipes CP22a, CP22b and CP22c are shown and are formed to extend from the first end to the second end, from the second end to the first end, and then from the first end to the second end to form a Z shape between the first end and the second end. Figure 6 As shown, in the cooling pipe CP22 according to the comparative example, the refrigerant flowing in from the inlet port flows from the first end, sequentially passes through the cooling pipes CP22a, CP22b, and CP22c, and reaches the second end.

[0074] As mentioned above, in Figure 6 In the comparative example shown, cooling pipes CP1 for cooling battery cell stack CS1 and cooling pipes CP2 for cooling battery cell stack CS2 are connected in parallel, cooling both battery cell stacks CS1 and CS2 simultaneously. Therefore, at first glance, it appears that both battery cell stacks CS1 and CS2 are cooled evenly. However, in reality, the refrigerant pressure loss in the comparative example is significant, making it impossible to evenly cool both battery cell stacks CS1 and CS2. Furthermore, as the number of battery cell stacks arranged side by side increases, the refrigerant pressure loss further increases, further deteriorating cooling uniformity.

[0075] On the contrary, Figure 5 In the illustrated embodiment of the present disclosure, cooling pipe CP1 for cooling battery cell stack CS1 and cooling pipe CP2 for cooling battery cell stack CS2 are connected in series, so that battery cell stack CS1 is cooled first and then battery cell stack CS2. Therefore, compared with the comparative example, the pressure loss of the refrigerant can be further reduced, so that battery cell stacks CS1 and CS2 can be cooled more evenly. Further, in Figure 5 In the embodiment shown, no Figure 6 Inflow pipe PI and outflow pipe PO are shown.

[0076] It is worth noting that the battery according to this embodiment may include a plurality of battery cell stacks CS1 through which the refrigerant flows first and is therefore cooled first, and a plurality of battery cell stacks CS2 through which the refrigerant flows later and is therefore cooled later. In this case, in the battery according to this embodiment, when the number of first battery cell stacks CS1 and second battery cell stacks CS2 is equal to each other, the battery cell stacks can be effectively and uniformly cooled.

[0077] As described above, in the battery according to this embodiment, refrigerant flowing in from inlet port IN first passes through cooling pipe CP1 for cooling battery cell stack CS1 from the first end, then passes through cooling pipe CP2 for cooling battery cell stack CS2 from the second end, and flows out through outlet port OUT. Therefore, compared to a comparative example in which cooling pipe CP1 for cooling battery cell stack CS1 and cooling pipe CP2 for cooling battery cell stack CS2 are connected in parallel, with refrigerant flowing from the first end to the second end in both cases, the battery according to this embodiment is able to further reduce refrigerant pressure loss and more evenly cool the battery cell stack.

[0078] From the disclosure thus described, it is obvious that the embodiments of the present disclosure may be varied in various ways. Such variations should not be regarded as departing from the spirit and scope of the present disclosure, and all such modifications obvious to those skilled in the art are intended to be included within the scope of the appended claims.

Claims

1. A battery comprising: a first battery cell stack and a second battery cell stack arranged side by side; as well as First cooling pipes and second cooling pipes are respectively disposed below the first battery cell stack and the second battery cell stack and configured to cool the first battery cell stack and the second battery cell stack, respectively, wherein: The first cooling tube and the second cooling tube extend from first ends of the first battery cell stack and the second battery cell stack, respectively, to second ends thereof and are connected to each other at the second ends. both an inlet port and an outlet port for refrigerant to flow through the first and second cooling tubes are provided at the first end, and The refrigerant flowing in from the inlet port first passes through the first cooling pipe from the first end, then passes through the second cooling pipe from the second end, and flows out from the outlet port.

2. The battery according to claim 1, wherein: In each of the first battery cell stack and the second battery cell stack, a plurality of rectangular battery cells are stacked on each other, Terminals are provided on both end faces in the longitudinal direction of each of the plurality of rectangular battery cells. A pair of first cooling pipes are provided at both ends of the first battery cell stack in the width direction, and A pair of second cooling pipes is provided at both ends in the width direction of the second battery cell stack.

3. The battery according to claim 2, wherein Each of the pair of first cooling tubes and the pair of second cooling tubes is formed to extend from the first end to the second end, from the second end to the first end, and then from the first end to the second end to form a Z shape between the first end and the second end.

4. The battery according to claim 3, wherein: In each of the pair of first cooling pipes, the refrigerant flows from one end in the width direction of the first battery cell stack toward the center thereof, and In each of the pair of second cooling pipes, the refrigerant flows from one end in the width direction of the second battery cell stack toward the center thereof. 5 . The battery according to claim 1 , further comprising a plurality of first battery cell stacks and a plurality of second battery cell stacks.

6. The battery according to claim 5, wherein The numbers of the first battery cell stacks and the second battery cell stacks are equal to each other.

7. The battery according to any one of claims 1 to 4, further comprising a housing configured to accommodate the first battery cell stack and the second battery cell stack, wherein The first cooling pipe and the second cooling pipe are arranged below the bottom plate of the housing.

Images