Cooler and battery housing

Abstract

To prevent a coolant from getting onto a battery when a cooler is broken by external impact while suppressing an increase in size of the cooler and an increase in pressure loss of the coolant.SOLUTION: A cooler 4 for cooling a battery 2, includes: a cooling plate portion 21 having a cooling liquid passage 11 and a first opening 26 and a second opening 27 for opening the cooling liquid passage 11; and a first lid portion 31 and a second lid portion 41 joined to the cooling plate portion 21 so as to cover the first opening 26 and the second opening 27. The cooling plate portion 21 has: a cooling wall portion 22 arranged on the battery 2 side; and a bottom wall portion 23 arranged on the opposite side of the cooling wall portion 22 from the battery 2 and facing the cooling wall portion 22. The first lid portion 31 or the second lid portion 41 is arranged on the bottom wall portion 23 side of the cooling wall portion 22, and the breaking strength of the first lid portion 31 or the second lid portion 41 is lower than the breaking strength of the cooling wall portion 22.SELECTED DRAWING: Figure 4

Description

Technical Field

[0001] One aspect of the present invention relates to a cooler for cooling a battery or the like.

Background Art

[0002] Patent Document 1 describes a cooler for cooling a storage battery (battery) mounted on a vehicle. This cooler includes a cooling plate that covers the bottom surface side of the storage battery and forms a coolant pipe. In this cooler, a concave stripe extending along the extending direction of the coolant flow path is formed on the bottom wall portion, which is the bottom surface of the coolant pipe on the side opposite to the storage battery. Thereby, when an impact is applied to the floor surface of the vehicle, the bottom surface portion can be preferentially damaged, so that it is possible to appropriately prevent the coolant from hitting the storage battery.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] The concave stripe described in Patent Document 1 is formed by making only a part of the thickness of the cooling plate thinner. However, when the cooling plate is extrusion-molded, if only a part of the thickness of the cooling plate is made thinner,the flow of the material may deteriorate and molding defects may occur. Therefore, when making only a part of the thickness of the cooling plate thinner, it is necessary to increase the overall thickness of the cooling plate. As a result, there is a problem of increasing the size of the cooling plate. Moreover, when a concave stripe is formed in the coolant pipe, turbulent flow is likely to occur in the coolant flowing through the coolant pipe. For this reason, there is also a problem that the pressure loss of the coolant flowing through the coolant pipe increases.

[0005] Therefore, one aspect of the present invention aims to provide a cooler that can suppress the increase in size of the cooler and the increase in pressure loss of the coolant, while also preventing the coolant from coming into contact with the battery when it is damaged by an external impact. [Means for solving the problem]

[0006] [1] A cooler according to one aspect of the present invention is a cooler for cooling a battery, comprising a cooling plate portion having a coolant passage and an opening that opens the coolant passage, and a lid portion joined to the cooling plate portion so as to cover the opening, wherein the cooling plate portion has a cooling wall portion arranged on the battery side and a bottom wall portion arranged on the opposite side of the cooling wall portion from the battery and facing the cooling wall portion, and the lid portion is arranged on the bottom wall portion side of the cooling wall portion, and the fracture strength of the lid portion is lower than that of the cooling wall portion.

[0007] In this cooler, the cooling wall of the cooling plate is positioned on the battery side, and the battery can be cooled by circulating the coolant through the coolant passage. Furthermore, the fracture strength of the lid is lower than that of the cooling wall. Therefore, even without forming a recess in the cooling plate, the lid is more likely to break before the cooling wall when subjected to impact. This suppresses the need to increase the size of the cooler and the increase in coolant pressure loss, while also preventing coolant from spilling onto the battery when the cooler is damaged by an external impact. Note that the failure of the lid includes not only the failure of the lid itself, but also the failure of the joint between the cooling plate and the lid.

[0008] [2] In the cooler described in [1], the cooling plate portion further has a pair of side walls connected to the cooling wall portion and the bottom wall portion and facing each other, and the fracture strength of the lid portion may be lower than the fracture strength of the bottom wall portion and the pair of side walls portion. In this cooler, because the fracture strength of the lid portion is lower than the fracture strength of the bottom wall portion and the pair of side walls portion, the lid portion is more likely to break before the bottom wall portion and the pair of side walls portion are broken when subjected to impact. This further suppresses the coolant from spilling onto the battery when the cooler is broken by an external impact.

[0009] [3] In the cooler described in [1] or [2], the thickness of the lid portion may be thinner than the thickness of the cooling wall portion. In this cooler, by making the thickness of the lid portion thinner than the thickness of the cooling wall portion, the fracture strength of the lid portion can be made lower than that of the cooling wall portion.

[0010] [4] In the cooler described in any one of [1] to [3], the cooling wall portion has a cooling wall joint portion that is joined to the lid portion, and the lid portion has a lid joint portion that is joined to the cooling wall portion, and the plate thickness of the lid joint portion may be thinner than the plate thickness of the cooling wall joint portion. In this cooler, by making the plate thickness of the lid joint portion thinner than the plate thickness of the cooling wall joint portion, the fracture strength of the lid portion can be made lower than the fracture strength of the cooling wall portion.

[0011] [5] In any one of the coolers described in [1] to [4], the lid may have a weaker portion that is more prone to fracture than other parts of the lid. In this cooler, having a weaker portion that is more prone to fracture than other parts of the lid makes it possible to lower the fracture strength of the lid than that of the cooling wall. In addition, when subjected to an external impact, the lid is more likely to break from the weaker portion, making it easier to control the starting point and progression of the lid's fracture.

[0012] [6] In any one of the coolers described in [1] to [5], the lid may have a notch. In this cooler, having a notch in the lid makes it possible to lower the fracture strength of the lid than that of the cooling wall. Also, when subjected to an external impact, the lid is more likely to break from the notch, making it easier to control the starting point and progression of the lid's failure.

[0013] [7] In the cooler described in any one of [1] to [6], the lid is positioned at the end of the cooling plate in the longitudinal direction, and the cooling plate and the lid may be joined in such a way that the joint between the cooling plate and the lid breaks before the cooling wall is destroyed when subjected to an external impact from the longitudinal direction. In this cooler, the cooling plate and the lid are joined in such a way that the joint between the cooling plate and the lid breaks before the cooling wall is destroyed when subjected to an external impact from the longitudinal direction. Therefore, when subjected to an external impact from the longitudinal direction, the joint between the cooling plate and the lid is more likely to break before the cooling wall is destroyed. This further reduces the amount of coolant that comes into contact with the battery when the cooler is destroyed by an external impact from the longitudinal direction.

[0014] [8] In any one of the coolers described in [1] to [7], the joint strength between the cooling plate and the lid may be lower than the fracture strength of the cooling wall. In this cooler, the fracture strength of the lid can be made lower than the fracture strength of the cooling wall by having a joint strength between the cooling plate and the lid that is lower than the fracture strength of the cooling wall.

[0015] [9] In the cooler described in any one of [1] to [8], the lid is joined to the cooling wall by welding, and the welding width between the cooling wall and the lid may be narrower than the plate thickness of the cooling wall. In this cooler, the lid is joined to the cooling wall by welding, and the welding width between the cooling wall and the lid is narrower than the plate thickness of the cooling wall, which makes it possible to lower the fracture strength of the lid to be lower than that of the cooling wall.

[0016]

[10] In the cooler described in any one of [1] to [9], the lid portion has a lid body joined to the cooling plate portion, and a port joined to the lid body to which a cooling fluid tube for supplying or discharging cooling fluid to or from the cooling fluid passage is connected, and the fracture strength of the port may be lower than that of the cooling wall portion. In this cooler, the fracture strength of the lid portion can be made lower than that of the cooling wall portion by having a fracture strength of the port lower than that of the cooling wall portion. Note that the fracture of the port includes not only the fracture of the port itself, but also the fracture of the joint between the lid body and the port.

[0017]

[11] In a cooler described in any one of [1] to

[10] , the lid portion has a lid body joined to a cooling plate portion, and a port joined to the lid body to which a cooling fluid tube for supplying or discharging cooling fluid to or from the cooling fluid passage is connected, and the joint strength between the lid body and the port may be lower than the fracture strength of the cooling wall portion. In this cooler, the fracture strength of the lid portion can be made lower than the fracture strength of the cooling wall portion by having a joint strength between the lid body and the port lower than the fracture strength of the cooling wall portion.

[0018]

[12] A battery housing according to one aspect of the present invention is a battery housing for housing a battery, comprising a frame arranged around the battery and a cooler according to any one of [1] to

[11] attached to the frame on which the battery is placed. In this battery housing, because the above-described cooler is provided, it is possible to suppress the enlargement of the cooler and the increase in the pressure loss of the coolant, while also suppressing the coolant from spilling onto the battery when the cooler is damaged by an external impact.

[0019] It is as follows: [Effects of the Invention]

[0020] According to one aspect of the present invention, it is possible to suppress the enlargement of the cooler and the increase in the pressure loss of the coolant, while also preventing the coolant from spilling onto the battery when it is damaged by impact. [Brief explanation of the drawing]

[0021] [Figure 1] It is a perspective view seen from below showing the battery housing according to the present embodiment. [Figure 2] It is an exploded perspective view seen from below of the battery housing shown in FIG. 1. [Figure 3] It is a perspective view seen from below showing the cooler according to the present embodiment. [Figure 4] It is a cross-sectional view taken along line IV-IV shown in FIG. 3. [Figure 5] It is a bottom view showing an end portion of the cooler in the first longitudinal direction. [Figure 6] It is a bottom view showing an end portion of the cooler in the second longitudinal direction. [Figure 7] It is a perspective view seen from below showing a state before joining the cooling plate portion and the first lid portion of an end portion of the cooler in the first longitudinal direction. [Figure 8] It is a perspective view seen from below showing a state before joining the cooling plate portion and the second lid portion of an end portion of the cooler in the second longitudinal direction. [Figure 9] It is a side view showing an enlarged view of a joint portion between the cooling wall portion and the first lid portion or the second lid portion. [Figure 10] It is a perspective view seen from below showing a modified example of the first lid portion. [Figure 11] It is a perspective view seen from below showing a modified example of the second lid portion. [Figure 12] It is a partially enlarged view of the first lid portion or the second lid portion shown in FIG. 4. [Figure 13] It is a bottom view showing a modified example of the cooler. [Figure 14] It is a perspective view seen from below showing a state before joining the cooling plate portion and the first lid portion of an end portion of the cooler in the first longitudinal direction shown in FIG. 13. [Figure 15] It is a perspective view seen from below showing a state before joining the cooling plate portion and the second lid portion of an end portion of the cooler in the second longitudinal direction shown in FIG. 13.

MODE FOR CARRYING OUT THE INVENTION

[0022] The cooler and battery housing according to this embodiment will be described below with reference to the drawings. The cooler according to this embodiment is for cooling a battery mounted in a vehicle such as an electric vehicle. The battery housing according to this embodiment is for housing and cooling a battery mounted in a vehicle such as an electric vehicle. In each figure, the same or corresponding elements are denoted by the same reference numerals, and redundant explanations are omitted.

[0023] Figure 1 is a perspective view from below showing the battery housing according to this embodiment. Figure 2 is an exploded perspective view from below showing the battery housing shown in Figure 1. As shown in Figures 1 and 2, the battery housing 1 according to this embodiment is a housing for housing a plurality of batteries 2. The battery housing 1 is formed in the shape of a thin rectangular plate, for example, to be mounted under the floor of a vehicle. As the battery 2, for example, a lithium-ion battery mounted in a vehicle is used. The battery 2 is formed in the shape of an elongated rectangular plate. The plurality of batteries 2 are housed in the battery housing 1 in an arrangement in the direction of the short side of each battery 2. In the battery housing 1, the direction that is the short side of each battery 2 is called the first direction D1, and the direction that is the long side of each battery 2 is called the second direction D2. The second direction D2 is perpendicular to the first direction D1.

[0024] The battery housing 1 comprises a frame 3 arranged around a plurality of batteries 2, and a plurality of coolers 4 connected to the frame 3 on which the plurality of batteries 2 are mounted.

[0025] The frame 3 has a pair of side members 5, 5 extending in a first direction D1 and facing each other, and a pair of cross members 6, 6 extending in a second direction D2 and facing each other. The frame 3 is formed in a rectangular frame shape by connecting both ends of the pair of side members 5, 5 and both ends of the pair of cross members 6, 6. When the battery housing 1 is mounted on a vehicle, for example, the first direction D1 from which the pair of side members 5, 5 extend is oriented in the vehicle's front-rear direction, and the second direction D2 from which the pair of cross members 6, 6 extend is oriented in the vehicle's width direction.

[0026] Multiple coolers 4 are attached to the frame 3 to form the bottom surface of the battery housing 1. Each cooler 4 is provided corresponding to each battery 2, and each cooler 4 cools each of the batteries 2 placed on it. The coolers 4 are formed in the shape of elongated rectangular plates corresponding to the batteries 2. In other words, the multiple coolers 4 extend in the second direction D2 and are arranged in the first direction D1. The multiple coolers 4 can be attached to the frame 3 by, for example, screwing screws 7 from the multiple coolers 4 into the frame 3.

[0027] Figure 3 is a perspective view from below showing the cooler according to this embodiment. Figure 4 is a cross-sectional view taken along the line IV-IV shown in Figure 3. As shown in Figures 1 to 4, the cooler 4 according to this embodiment is formed in a rectangular shape extending in the longitudinal direction L and the width direction W perpendicular to the longitudinal direction L, and is thinner in the height direction H perpendicular to the longitudinal direction L and the width direction W. The cooler 4 is formed so that the longitudinal direction L is longer than the width direction W. In the battery housing 1, the width direction W is the first direction D1, and the longitudinal direction L is the second direction D2. One direction of the longitudinal direction L is called the first longitudinal direction L1, and the other direction of the longitudinal direction L is called the second longitudinal direction L2. Also, one direction of the height direction H that faces the battery 2 is called the upward direction H1, and the other direction of the height direction H that faces the opposite side of the battery 2 is called the downward direction H2.

[0028] Figure 5 is a bottom view showing the end of the cooler in the first longitudinal direction. Figure 6 is a bottom view showing the end of the cooler in the second longitudinal direction. As shown in Figures 1 to 6, the cooler 4 comprises a coolant passage 11, a first port 12, a second port 13, a first mounting portion 14, and a second mounting portion 15.

[0029] The coolant passage 11 is a passage (space) through which coolant can flow. The first port 12 and the second port 13 are ports that communicate with the coolant passage 11 and supply or discharge coolant to or from the coolant passage 11. Coolant tubes (not shown) for supplying or discharging coolant to or from the coolant passage 11 are connected to the first port 12 and the second port 13. The first port 12 is located at the end of the cooler 4 in the first longitudinal direction L1. The second port 13 is located at the end of the cooler 4 in the second longitudinal direction L2. Therefore, the coolant is supplied to the coolant passage 11 from either the first port 12 or the second port 13, flows through the coolant passage 11 in the longitudinal direction L, and is discharged from either the first port 12 or the second port 13. The coolant cools the cooler 4 by absorbing heat from the cooler 4 as it flows through the coolant passage 11.

[0030] The first mounting portion 14 and the second mounting portion 15 are for attaching the cooler 4 to the frame 3 of the battery housing 1. The first mounting portion 14 is located at the end of the cooler 4 in the first longitudinal direction L1 and is attached to one side member 5 of the frame 3. The second mounting portion 15 is located at the end of the cooler 4 in the second longitudinal direction L2 and is attached to the other side member 5 of the frame 3. The first mounting portion 14 and the second mounting portion 15 are, for example, through holes into which screws 7 for attaching the cooler 4 to the frame 3 are inserted.

[0031] Figure 7 is a perspective view from below showing the state of the first longitudinal end of the cooler before the cooling plate portion and the first lid portion are joined together. Figure 8 is a perspective view from below showing the state of the second longitudinal end of the cooler before the cooling plate portion and the second lid portion are joined together. As shown in Figures 1 to 8, the cooler 4 comprises a cooling plate portion 21 and a first lid portion 31 and a second lid portion 41 joined to the cooling plate portion 21.

[0032] The cooling plate section 21 forms the main body of the cooler 4 by creating a coolant passage 11. The cooling plate section 21 includes a cooling wall section 22, a bottom wall section 23, a pair of side wall sections 24, 24, and a plurality of partition walls 25.

[0033] The cooling wall portion 22 is the top wall portion of the cooler 4. The cooling wall portion 22 is positioned on the battery 2 side in order to cool the battery 2 by removing heat from it. The cooling wall portion 22 is formed in the shape of a rectangular plate extending in the longitudinal direction L and the width direction W. A part of the first mounting portion 14 is formed at the end of the cooling wall portion 22 in the first longitudinal direction L1, and a part of the second mounting portion 15 is formed at the end of the cooling wall portion 22 in the second longitudinal direction L2.

[0034] The bottom wall portion 23 is the bottom wall portion of the cooler 4. The bottom wall portion 23 is located on the opposite side of the cooling wall portion 22 from the battery 2 and faces the cooling wall portion 22. The bottom wall portion 23 is located below the cooling wall portion 22 in direction H2 and is formed in the same way as the cooling wall portion 22, extending in the longitudinal direction L and the width direction W as a rectangular plate.

[0035] The pair of side wall portions 24, 24 are the parts that form a pair of side walls of the cooler 4. The pair of side wall portions 24, 24 are connected to the cooling wall portion 22 and the bottom wall portion 23 and face each other in the width direction W. The pair of side wall portions 24, 24 are formed in the shape of elongated rectangular plates extending in the longitudinal direction L and the height direction H. The pair of side wall portions 24, 24 are connected at both ends in the height direction H to both ends in the width direction W of the cooling wall portion 22 and the bottom wall portion 23.

[0036] In the cooling plate section 21, a cooling liquid passage 11 is formed by the cooling wall section 22, the bottom wall section 23, and the pair of side walls 24, 24. In other words, the internal space of the cooling plate section 21 surrounded by the cooling wall section 22, the bottom wall section 23, and the pair of side walls 24, 24 constitutes the cooling liquid passage 11. Furthermore, in the cooling plate section 21, a first opening 26 and a second opening 27 are formed by the cooling wall section 22, the bottom wall section 23, and the pair of side walls 24, 24, which open the cooling liquid passage 11.

[0037] Multiple partition walls 25 extend in the longitudinal direction L and partition the coolant passage 11 in the width direction W. In other words, multiple partition walls 25 extending in the longitudinal direction L are arranged in the width direction W. Each of the multiple partition walls 25 is formed in the shape of an elongated rectangular plate extending in the longitudinal direction L and the height direction H. Each of the multiple partition walls 25 is connected to the cooling wall section 22 and the bottom wall section 23 at both ends in the height direction H. In the cooling plate section 21, the coolant passage 11 is partitioned into multiple partitioned coolant passages 28 by the multiple partition walls 25. The multiple partitioned coolant passages 28 extend in the longitudinal direction L and are arranged in the width direction W. Of the multiple compartmentalized coolant passages 28, the compartmentalized coolant passages 28 located at both ends in the width direction W are formed by a cooling wall portion 22, a bottom wall portion 23, a side wall portion 24, and a compartmentalized wall 25, while the remaining compartmentalized coolant passages 28 are formed by a cooling wall portion 22, a bottom wall portion 23, and a pair of adjacent compartmentalized walls 25.

[0038] The first opening 26 is at the end of the cooling plate portion 21 in the first longitudinal direction L1, opening the coolant passage 11 in the first longitudinal direction L1 and downward direction H2. The second opening 27 is at the end of the cooling plate portion 21 in the second longitudinal direction L2, opening the coolant passage 11 in the second longitudinal direction L2 and downward direction H2. The first opening 26 and the second opening 27 are formed by a cooling wall portion 22, a bottom wall portion 23, and a pair of side wall portions 24, 24. The first opening 26 and the second opening 27 are formed, for example, by cutting out the cooling wall portion 22, the bottom wall portion 23, and the pair of side wall portions 24, 24.

[0039] At the end of the cooling plate portion 21 in the first longitudinal direction L1, the cooling plate portion 21 is not provided on the side of the cooling liquid passage 11 in the first longitudinal direction L1, so the cooling liquid passage 11 is open in the first longitudinal direction L1. Also, at the end of the cooling plate portion 21 in the first longitudinal direction L1, the tip of the bottom wall portion 23 in the first longitudinal direction L1 is located on the second longitudinal direction L2 side than the tip of the cooling wall portion 22 in the first longitudinal direction L1, so the cooling liquid passage 11 is open downwards in direction H2. In other words, at the end of the cooling plate portion 21 in the first longitudinal direction L1, the cooling wall portion 22 is provided but the bottom wall portion 23 is not provided, so the cooling liquid passage 11 is open downwards in direction H2. At the end of the cooling plate portion 21 in the first longitudinal direction L1, as long as the cooling liquid passage 11 is open in the first longitudinal direction L1 and downwards in direction H2, the first opening 26 does not necessarily have to face downwards in direction H2. For example, the end faces of the pair of side wall portions 24, 24 on the first longitudinal direction L1 side may extend in the height direction H, so that the first opening 26 faces the first longitudinal direction L1.

[0040] At the end of the cooling plate portion 21 in the second longitudinal direction L2, the cooling plate portion 21 is not provided on the side of the cooling liquid passage 11 in the second longitudinal direction L2, so the cooling liquid passage 11 is open in the second longitudinal direction L2. Also, at the end of the cooling plate portion 21 in the second longitudinal direction L2, the tip of the bottom wall portion 23 in the second longitudinal direction L2 is located on the first longitudinal direction L1 side than the tip of the cooling wall portion 22 in the second longitudinal direction L2, so the cooling liquid passage 11 is open downwards in the H2 direction. In other words, at the end of the cooling plate portion 21 in the second longitudinal direction L2, the cooling wall portion 22 is provided but the bottom wall portion 23 is not provided, so the cooling liquid passage 11 is open downwards in the H2 direction. At the end of the cooling plate portion 21 in the second longitudinal direction L2, as long as the cooling liquid passage 11 is open in the first longitudinal direction L1 and downwards in the H2 direction, the second opening 27 does not necessarily have to face downwards in the H2 direction. For example, the end faces of the pair of side wall portions 24, 24 on the second longitudinal direction L2 may extend in the height direction H, so that the second opening 27 faces the second longitudinal direction L2.

[0041] As shown in Figures 1 to 5 and Figure 7, the first lid portion 31 is positioned on the bottom wall portion 23 side of the cooling wall portion 22. In other words, the first lid portion 31 is located in the downward direction H2 of the cooling wall portion 22. The first lid portion 31 is joined to the cooling plate portion 21 from the downward direction H2 so as to cover the first opening 26. The joining of the first lid portion 31 to the cooling plate portion 21 is not particularly limited, but can be done by welding, brazing, etc. In the drawings, the joint portion between the cooling plate portion 21 and the first lid portion 31 is shown with fine dot hatching.

[0042] The first lid portion 31 has a lid body 32 and a first port 12. The lid body 32 is the portion that is joined to the cooling plate portion 21. The lid body 32 forms a first chamber 33 that is positioned between the first port 12 and the plurality of compartmentalized coolant passages 28. The first chamber 33 is located on the first longitudinal L1 side of the plurality of compartmentalized coolant passages 28 and is a space that communicates with the plurality of compartmentalized coolant passages 28 and the first port 12. The first chamber 33 distributes or merges coolant between the first port 12 and the plurality of compartmentalized coolant passages 28.

[0043] A portion of the first mounting portion 14 is formed at the end of the first lid portion 31 in the first longitudinal direction L1. The first mounting portion 14 is formed by the overlapping portions of the cooling wall portion 22 of the cooling plate portion 21 and the first lid portion 31.

[0044] As shown in Figures 1-4, 6, and 8, the second lid portion 41 is positioned on the bottom wall portion 23 side of the cooling wall portion 22. In other words, the second lid portion 41 is located downward H2 of the cooling wall portion 22. The first lid portion 31 is joined to the cooling plate portion 21 from downward H2 so as to cover the second opening 27. The joining of the second lid portion 41 to the cooling plate portion 21 is not particularly limited, but can be done by welding, brazing, etc. In the drawings, the joint portion between the cooling plate portion 21 and the second lid portion 41 is shown with fine dot hatching.

[0045] The second lid portion 41 has a lid body 42 and a second port 13. The lid body 42 is the portion that is joined to the cooling plate portion 21. The lid body 42 forms a second chamber 43 that is positioned between the second port 13 and the plurality of compartmentalized coolant passages 28. The second chamber 43 is located on the second longitudinal L2 side of the plurality of compartmentalized coolant passages 28 and is a space that communicates with the plurality of compartmentalized coolant passages 28 and the second port 13. The second chamber 43 distributes or merges coolant between the second port 13 and the plurality of compartmentalized coolant passages 28.

[0046] A portion of the second mounting portion 15 is formed at the end of the second lid portion 41 in the second longitudinal direction L2. The second mounting portion 15 is formed by the overlapping portions of the cooling wall portion 22 of the cooling plate portion 21 and the second lid portion 41.

[0047] In the cooler 4 configured in this way, the fracture strength of the first lid 31 or the second lid 41 is lower than the fracture strength of the cooling wall 22. Furthermore, the fracture strength of the first lid 31 or the second lid 41 is lower than the fracture strength of the bottom wall 23 and the pair of side walls 24, 24. In this case, it is preferable that the fracture strength of both the first lid 31 and the second lid 41 is lower than the fracture strength of the cooling wall 22, the bottom wall 23, and the pair of side walls 24, 24, but the fracture strength of only one of the first lid 31 or the second lid 41 may be lower than the fracture strength of the cooling wall 22, the bottom wall 23, and the pair of side walls 24, 24. Note that the fracture of the first lid 31 or the second lid 41 includes not only the fracture of the first lid 31 or the second lid 41 itself, but also the fracture of the joint between the cooling plate 21 and the first lid 31 or the second lid 41.

[0048] Fracture strength refers to the strength required for an object to break or fracture. In other words, the higher the fracture strength, the less likely an object is to break or fracture; conversely, the lower the fracture strength, the more likely an object is to break or fracture. Fracture strength is, for example, the absolute value of the stress (fracture stress) at which an object breaks or fractures. Examples of fracture strength include compressive strength, tensile strength, and shear strength.

[0049] The specific configurations in which the fracture strength of the first lid 31 or the second lid 41 is lower than that of the cooling wall 22, and furthermore, the specific configurations in which the fracture strength of the first lid 31 or the second lid 41 is lower than that of the bottom wall 23 and the pair of side wall portions 24, 24, are not particularly limited.

[0050] Figure 9 is an enlarged side view of the joint between the cooling wall and the first or second lid. As shown in Figure 9, for example, the plate thickness t1 of the first lid 31 or the second lid 41 may be thinner than the plate thickness T1 of the cooling wall 22, so the fracture strength of the first lid 31 or the second lid 41 may be lower than the fracture strength of the cooling wall 22. Furthermore, the plate thickness t1 of the first lid 31 or the second lid 41 may be thinner than the plate thickness of the bottom wall 23 and the pair of side walls 24, 24, so the fracture strength of the first lid 31 or the second lid 41 may be lower than the fracture strength of the bottom wall 23 and the pair of side walls 24, 24. If the plate thickness t1 of the first lid 31 or the second lid 41 is not constant, this plate thickness t1 will be the plate thickness of the thinnest part of the first lid 31 or the second lid 41. If the thickness T1 of the cooling wall 22 is not constant, this thickness T1 will be the thickness of the thinnest part of the cooling wall 22. If the thicknesses of the bottom wall 23 and the pair of side walls 24, 24 are not constant, these thicknesses will be the thicknesses of the thinnest parts of the bottom wall 23 and the pair of side walls 24, 24, respectively.

[0051] Furthermore, the joints that connect the first lid portion 31 and the second lid portion 41 of the cooling wall portion 22 are called the cooling wall joint portion 22a, and the joints that connect the first lid portion 31 and the second lid portion 41 to the cooling wall portion 22 are called the first lid joint portion 31a and the second lid joint portion 41a. In this case, the plate thickness t2 of the first lid joint portion 31a or the second lid joint portion 41a may be thinner than the plate thickness T2 of the cooling wall joint portion 22a, so that the fracture strength of the first lid portion 31 or the second lid portion 41 is lower than the fracture strength of the cooling wall portion 22.

[0052] Furthermore, the first lid 31 or the second lid 41 may have a weaker portion that is more prone to fracture than other parts of the first lid 31 or the second lid 41, so that the fracture strength of the first lid 31 or the second lid 41 is lower than the fracture strength of the cooling wall 22. Moreover, the first lid 31 or the second lid 41 may have a weaker portion that is more prone to fracture than other parts of the first lid 31 or the second lid 41, so that the fracture strength of the first lid 31 or the second lid 41 is lower than the fracture strength of the bottom wall 23 and the pair of side wall portions 24, 24. The weaker portion can be formed, for example, by notches, grooves, holes, or thinning.

[0053] Figure 10 is a perspective view from below showing a modified example of the first lid. Figure 11 is a perspective view from below showing a modified example of the second lid. As shown in Figures 10 and 11, for example, the first lid 31 or the second lid 41 may have a notch 31b or notch 41b separate from the first mounting portion 14 or the second mounting portion 15, thereby lowering the fracture strength of the first lid 31 or the second lid 41 than the fracture strength of the cooling wall portion 22. Furthermore, the first lid 31 or the second lid 41 may have a notch 31b or notch 41b separate from the first mounting portion 14 or the second mounting portion 15, thereby lowering the fracture strength of the first lid 31 or the second lid 41 than the fracture strength of the bottom wall portion 23 and the pair of side wall portions 24, 24. The notches 31b or 41b of the first lid 31 or the second lid 41 also function as weaker areas that are more prone to fracture than other parts of the first lid 31 or the second lid 41.

[0054] Furthermore, the cooling plate portion 21 and the first lid portion 31 may be joined in such a way that the joint between the cooling plate portion 21 and the first lid portion 31 breaks before the cooling wall portion 22 breaks when subjected to an external impact from the first longitudinal direction L1, thereby ensuring that the fracture strength of the first lid portion 31 is lower than that of the cooling wall portion 22. Similarly, the cooling plate portion 21 and the second lid portion 41 may be joined in such a way that the joint between the cooling plate portion 21 and the second lid portion 41 breaks before the cooling wall portion 22 breaks when subjected to an external impact from the second longitudinal direction L2, thereby ensuring that the fracture strength of the second lid portion 41 is lower than that of the cooling wall portion 22.

[0055] Furthermore, the joint strength between the cooling plate portion 21 and the first lid portion 31 or the second lid portion 41 may be lower than the fracture strength of the cooling wall portion 22, thereby resulting in the fracture strength of the first lid portion 31 or the second lid portion 41 being lower than the fracture strength of the cooling wall portion 22. In addition, the joint strength between the cooling plate portion 21 and the first lid portion 31 or the second lid portion 41 may be lower than the fracture strength of the bottom wall portion 23 and the pair of side wall portions 24, 24, thereby resulting in the fracture strength of the first lid portion 31 or the second lid portion 41 being lower than the fracture strength of the bottom wall portion 23 and the pair of side wall portions 24, 24.

[0056] The joint strength between the cooling plate portion 21 and the first lid portion 31 or the second lid portion 41 can be adjusted by various means. For example, if the cooling plate portion 21 and the first lid portion 31 or the second lid portion 41 are joined by welding, the joint strength between the cooling plate portion 21 and the first lid portion 31 or the second lid portion 41 can be adjusted by the width or depth of the weld. For example, as shown in Figure 9, the welding width w1 between the cooling wall portion 22 and the first lid portion 31 or the second lid portion 41 may be narrower than the plate thickness T1 of the cooling wall portion 22, so that the fracture strength of the first lid portion 31 or the second lid portion 41 is lower than the fracture strength of the cooling wall portion 22.

[0057] Furthermore, if the fracture strength of the first port 12 or the second port 13 is lower than that of the cooling wall 22, the fracture strength of the first lid 31 or the second lid 41 may be lower than that of the cooling wall 22. In addition, if the fracture strength of the first port 12 or the second port 13 is lower than that of the bottom wall 23 and the pair of side walls 24, 24, the fracture strength of the first lid 31 or the second lid 41 may be lower than that of the bottom wall 23 and the pair of side walls 24, 24. Note that the fracture of the first port 12 or the second port 13 includes not only the fracture of the first port 12 or the second port 13 itself, but also the fracture of the joint between the first lid 31 or the second lid 41 and the first port 12 or the second port 13.

[0058] The specific configurations in which the fracture strength of the first port 12 or the second port 13 is lower than the fracture strength of the cooling wall portion 22, and furthermore, the specific configurations in which the fracture strength of the first port 12 or the second port 13 is lower than the fracture strength of the bottom wall portion 23 and the pair of side wall portions 24, 24, are not particularly limited.

[0059] Figure 12 is a partially enlarged view of the first or second lid shown in Figure 4. As shown in Figure 12, for example, the plate thickness t3 of the first port 12 or second port 13 may be thinner than the plate thickness T1 of the cooling wall 22, so that the fracture strength of the first port 12 or second port 13 is lower than the fracture strength of the cooling wall 22. Furthermore, the plate thickness t3 of the first port 12 or second port 13 may be thinner than the plate thickness of the bottom wall 23 and the pair of side walls 24, 24, so that the fracture strength of the first port 12 or second port 13 is lower than the fracture strength of the bottom wall 23 and the pair of side walls 24, 24.

[0060] Furthermore, the joint strength between the lid body 32 and the first port 12, or the joint strength between the lid body 42 and the second port 13, may be lower than the breaking strength of the cooling wall portion 22, thereby resulting in the breaking strength of the first port 12 or the second port 13 being lower than the breaking strength of the cooling wall portion 22. In addition, the joint strength between the lid body 32 and the first port 12, or the joint strength between the lid body 42 and the second port 13, may be lower than the breaking strength of the bottom wall portion 23 and the pair of side wall portions 24, 24, thereby resulting in the breaking strength of the first port 12 or the second port 13 being lower than the breaking strength of the bottom wall portion 23 and the pair of side wall portions 24, 24.

[0061] The joint strength between the lid body 32 and the first port 12, and the joint strength between the lid body 42 and the second port 13 can be adjusted by various means. For example, if the lid body 32 and the first port 12 are joined by welding, and the lid body 42 and the second port 13 are joined by welding, the joint strength between the lid body 32 and the first port 12, and the joint strength between the lid body 42 and the second port 13 can be adjusted by the width or depth of these welds. For example, as shown in Figure 12, if the first port 12 or the second port 13 is welded to the lid body 32 or the lid body 42 while inserted into a hole formed in the lid body 32 or the lid body 42, the welding depth d1 between the lid body 32 or the lid body 42 and the first port 12 or the second port 13 may be shallower than the plate thickness T1 of the cooling wall portion 22 (see Figure 9), resulting in the breaking strength of the first port 12 or the second port 13 being lower than the breaking strength of the cooling wall portion 22. Furthermore, the welding depth d1 between the lid body 32 or lid body 42 and the first port 12 or second port 13 may be shallower than the plate thickness of the bottom wall 23 and the pair of side wall portions 24, 24, so that the breaking strength of the first port 12 or second port 13 is lower than the breaking strength of the bottom wall 23 and the pair of side wall portions 24, 24.

[0062] As described above, in the cooler 4 according to this embodiment, the cooling wall portion 22 of the cooling plate portion 21 is positioned on the battery 2 side, and the coolant is circulated through the coolant passage 11 to cool the battery 2. Furthermore, the fracture strength of the first lid portion 31 or the second lid portion 41 is lower than the fracture strength of the cooling wall portion 22. Therefore, even without forming a recess in the cooling plate portion 21, when subjected to impact, the first lid portion 31 or the second lid portion 41 is more likely to break before the cooling wall portion 22 is broken. This makes it possible to suppress the enlargement of the cooler 4 and the increase in coolant pressure loss, while also preventing the coolant from spilling onto the battery 2 when the cooler 4 is destroyed by an external impact.

[0063] Furthermore, in this cooler 4, the fracture strength of the first lid 31 or the second lid 41 is lower than that of the bottom wall 23 and the pair of side walls 24, 24. Therefore, when subjected to impact, the first lid 31 or the second lid 41 is more likely to break before the bottom wall 23 and the pair of side walls 24, 24 are broken. This further reduces the amount of coolant that spills onto the battery 2 when the cooler 4 is destroyed by an external impact.

[0064] Furthermore, in this cooler 4, the plate thickness t1 of the first lid 31 or the second lid 41 is thinner than the plate thickness T1 of the cooling wall 22, thereby making the fracture strength of the first lid 31 or the second lid 41 lower than the fracture strength of the cooling wall 22.

[0065] Furthermore, in this cooler 4, the plate thickness t2 of the first lid joint 31a or the second lid joint 41a is thinner than the plate thickness T2 of the cooling wall joint 22a, thereby making the fracture strength of the first lid 31 or the second lid 41 lower than the fracture strength of the cooling wall 22.

[0066] Furthermore, in this cooler 4, the first lid 31 or the second lid 41 has a weak point that is more prone to fracture than other parts of the first lid 31 or the second lid 41, thereby making the fracture strength of the first lid 31 or the second lid 41 lower than that of the cooling wall 22. Also, when subjected to an external impact, the first lid 31 or the second lid 41 is more likely to break from the weak point, making it easier to control the starting point and progression of fracture of the first lid 31 or the second lid 41.

[0067] Furthermore, in this cooler 4, the first lid 31 or the second lid 41 has a notch 31b or notch 41b, which makes it possible to lower the fracture strength of the first lid 31 or the second lid 41 than that of the cooling wall 22. Also, when subjected to an external impact, the first lid 31 or the second lid 41 is more likely to break from the notch 31b or notch 41b, making it easier to control the starting point and progression of the fracture of the first lid 31 or the second lid 41.

[0068] Furthermore, in this cooler 4, the cooling plate portion 21 and the first lid portion 31 or the second lid portion 41 are joined in such a way that when subjected to an external impact from the longitudinal direction L, the joint between the cooling plate portion 21 and the first lid portion 31 or the second lid portion 41 is destroyed before the cooling wall portion 22 is destroyed. Therefore, when subjected to an external impact from the longitudinal direction L, the joint between the cooling plate portion 21 and the first lid portion 31 or the second lid portion 41 is more likely to be destroyed before the cooling wall portion 22 is destroyed. This further suppresses the leakage of coolant onto the battery 2 when the cooler 4 is destroyed by an external impact received from the longitudinal direction L. For example, if the cooler 4 is positioned on a vehicle with its longitudinal direction L facing the vehicle's width direction, when subjected to an impact from the side of the vehicle, the joint between the cooling plate portion 21 and the first lid portion 31 or the second lid portion 41 is more likely to be destroyed before the cooling wall portion 22 is destroyed. This further reduces the amount of coolant that comes into contact with the battery 2 when the cooler 4 is damaged by an impact from the side of the vehicle.

[0069] Furthermore, in this cooler 4, the bonding strength between the cooling plate portion 21 and the first lid portion 31 or the second lid portion 41 is lower than the fracture strength of the cooling wall portion 22, thereby making the fracture strength of the first lid portion 31 or the second lid portion 41 lower than the fracture strength of the cooling wall portion 22.

[0070] Furthermore, in this cooler 4, the first lid 31 or the second lid 41 is joined to the cooling wall 22 by welding, and the welding width w1 between the cooling wall 22 and the first lid 31 or the second lid 41 is narrower than the plate thickness T1 of the cooling wall 22, so that the fracture strength of the first lid 31 or the second lid 41 can be lower than the fracture strength of the cooling wall 22.

[0071] Furthermore, in this cooler 4, the fracture strength of the first port 12 or the second port 13 is lower than the fracture strength of the cooling wall 22, thereby making the fracture strength of the first cover 31 or the second cover 41 lower than the fracture strength of the cooling wall 22.

[0072] Furthermore, in this cooler 4, the joint strength between the lid body 32 and the first port 12, or the joint strength between the lid body 42 and the second port 13, is lower than the breaking strength of the cooling wall portion 22. This makes it possible to lower the breaking strength of the joint between the lid body 32 or lid body 42 and the first port 12 or second port 13 to less than the breaking strength of the cooling wall portion 22.

[0073] In this embodiment, the battery housing 1 is equipped with the cooler 4 described above, which suppresses the need to enlarge the cooler 4 and the increase in pressure loss of the coolant, while also preventing the coolant from spilling onto the battery 2 when the cooler 4 is damaged by an external impact.

[0074] Although embodiments of the present invention have been described above, the present invention is not limited to the embodiments described above.

[0075] For example, in the above embodiment, the first lid has a first port and the second lid has a second port, and the coolant flows through the coolant passage 11 in only one direction L in the longitudinal direction. However, one lid may have both a first port and a second port, and the coolant may flow through the coolant passage in a U-shape, reciprocating manner.

[0076] Figure 13 is a bottom view showing a modified cooler. Figure 14 is a perspective view from below showing the end of the cooler in the first longitudinal direction shown in Figure 13, before the cooling plate portion and the first lid portion are joined together. Figure 15 is a perspective view from below showing the end of the cooler in the second longitudinal direction shown in Figure 13, before the cooling plate portion and the second lid portion are joined together. As shown in Figures 13 to 15, in the modified cooler 4A, the coolant passage 11 formed in the cooling plate portion 21A is separated in the width direction W into a first coolant passage 11A and a second coolant passage 11B by a separation wall 51. The first lid portion 31A has both a first port 12 and a second port 13. In the lid body 32A of the first lid portion 31A, a first chamber 33A1 communicating with the first coolant passage 11A and the first port 12 is separated from a first chamber 33A2 communicating with the second coolant passage 11B and the second port 13. On the other hand, the second lid portion 41A has a second chamber 43A that communicates with both the first coolant passage 11A and the second coolant passage 11B, but does not have either the first port 12 or the second port 13. Therefore, the coolant supplied from the first port 12 is supplied from the first chamber 33A1 to the first coolant passage 11A and flows in the first longitudinal direction L1, is folded back in a U-shape in the second chamber 43A, is supplied from the second chamber 43A to the second coolant passage 11B and flows in the second longitudinal direction L2, and is discharged from the first chamber 33A2 to the second port 13.

[0077] Even in such a cooler 4A, the fracture strength of the first lid 31A or the second lid 41A is lower than that of the cooling wall 22, thereby suppressing the enlargement of the cooler 4A and the increase in coolant pressure loss, while also preventing the coolant from spilling onto the battery 2 when the cooler 4A is destroyed by an external impact. [Explanation of symbols]

[0078] 1...Battery housing, 2...Battery, 3...Frame, 4...Cooler, 4A...Cooler, 5...Side member, 6...Cross member, 11...Coolant passage, 11A...First coolant passage, 11B...Second coolant passage, 12...First port, 13...Second port, 14...First mounting section, 15...Second mounting section, 21...Cooling plate section, 21A...Cooling plate section, 22...Cooling wall section, 22a...Cooling wall joint section, 23...Bottom wall section, 24...Side wall section, 25...Partition wall, 26...First opening, 27...Second opening, 28...Partition coolant passage, 31...First lid section, 31A...First lid section, 31a... First lid joint, 31b...notch, 32...lid body, 33...first chamber, 33A1...first chamber, 33A2...first chamber, 41...second lid section, 41A...second lid section, 41a...second lid joint, 41b...notch, 42...lid body, 43...second chamber, 43A...second chamber, 51...separation wall, D1...first direction, D2...second direction, H...height direction, H1...upward direction, H2...downward direction, L...longitudinal direction, L1...first longitudinal direction, L2...second longitudinal direction, W...width direction, T1...plate thickness, T2...plate thickness, t1...plate thickness, t2...plate thickness, t3...plate thickness, w1...weld width.

Claims

1. A cooler for cooling a battery, A cooling plate portion having a coolant passage and an opening that opens the coolant passage, The system comprises a lid portion joined to the cooling plate portion so as to cover the opening, The cooling plate portion has a cooling wall portion located on the battery side and a bottom wall portion located on the opposite side of the cooling wall portion from the battery and facing the cooling wall portion. The lid portion is positioned on the bottom wall side of the cooling wall portion. The fracture strength of the lid is lower than that of the cooling wall. cooler.

2. The cooling plate portion further has a pair of side wall portions that are connected to the cooling wall portion and the bottom wall portion and face each other, The fracture strength of the lid is lower than that of the bottom wall and the pair of side walls. The cooler according to claim 1.

3. The thickness of the lid portion is thinner than the thickness of the cooling wall portion. The cooler according to claim 1.

4. The cooling wall portion has a cooling wall joint portion that is joined to the lid portion, The lid portion has a lid joint portion that is joined to the cooling wall portion, The plate thickness of the lid joint is thinner than the plate thickness of the cooling wall joint. The cooler according to claim 1.

5. The lid portion has a weaker part that is more prone to breakage than other parts of the lid portion. The cooler according to claim 1.

6. The lid portion has a notch, The cooler according to claim 1.

7. The lid portion is positioned at the end of the cooling plate portion in the longitudinal direction, The cooling plate portion and the lid portion are joined together such that the joint between the cooling plate portion and the lid portion breaks before the cooling wall portion is destroyed when subjected to an external impact from the longitudinal direction. The cooler according to claim 1.

8. The bonding strength between the cooling plate and the lid is lower than the fracture strength of the cooling wall. The cooler according to claim 1.

9. The lid portion is joined to the cooling wall portion by welding. The welding width between the cooling wall and the lid is narrower than the plate thickness of the cooling wall. The cooler according to claim 1.

10. The aforementioned lid portion is The lid body is joined to the aforementioned cooling plate section, It has a port that is joined to the lid body and to which a coolant tube is connected for supplying or discharging coolant to the coolant passage, The fracture strength of the port is lower than that of the cooling wall. The cooler according to claim 1.

11. The aforementioned lid portion is The lid body is joined to the aforementioned cooling plate section, It has a port that is joined to the lid body and to which a coolant tube is connected for supplying or discharging coolant to the coolant passage, The bonding strength between the lid body and the port is lower than the breaking strength of the cooling wall. The cooler according to claim 1.

12. A battery housing that contains a battery, A frame positioned around the aforementioned battery, The device comprises a cooler according to any one of claims 1 to 11, which is attached to the frame and on which the battery is mounted, Battery housing.

Images