Battery cooler

Abstract

To improve the cooling efficiency.SOLUTION: A battery cooler 30 includes: a coolant case 36 having a heat transfer portion 34 to which heat from a battery cells 11 is transferred; and a coolant flow path 44 formed within the coolant case 36 and facing the heat transfer portion 34. The coolant flow path 44 is constituted by connecting a laminar flow portion 45 having a constant cross-sectional area in a flow direction of the coolant and a turbulent flow portion 46 having a cross-sectional area that changes in the flow direction of the coolant. In the turbulent flow portion 46, a turbulent flow of the coolant is generated by the change in cross-sectional area, such that the amount of coolant that comes into contact with the heat transfer portion 34 per unit time is greater than that in the laminar flow portion 45.SELECTED DRAWING: Figure 6

Description

[Technical Field]

[0001] The present invention relates to a battery cooler. [Background technology]

[0002] Patent Document 1 discloses a battery pack structure having a plate-shaped cooling member and multiple wall-shaped frames attached to the outer periphery of the cooling member. The cooling member is a member for preventing overheating of the battery pack, and is made up of an upper cooling layer and a lower cooling layer stacked one above the other to form an integrated structure. A cooling flow path is formed between the upper and lower cooling layers to allow cooling water to flow. The battery pack is attached in a state where it is placed on the top surface of the cooling member. Heat generated in the battery pack is removed by the cooling member via the upper cooling layer. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2021-140863 Summary of the Invention [Problem to be solved by the invention]

[0004] The cooling water removes heat from the battery pack by coming into contact with the upper cooling layer. However, the cooling member has a constant width of the cooling flow path, and the cooling water flows in a laminar manner. Therefore, only a portion of the cooling water comes into contact with the upper cooling layer as it passes through the cooling flow path, and the amount of heat transferred from the upper cooling layer to the cooling water is small.

[0005] The present invention was completed in view of the above circumstances, and an object of the present invention is to improve cooling efficiency. [Means for solving the problem]

[0006] The battery cooler of the present disclosure comprises: a refrigerant case having a heat transfer portion to which heat from the battery cell is transferred; a refrigerant flow path formed in the refrigerant case and facing the heat transfer portion, The refrigerant flow path is configured by connecting a laminar flow portion, the cross-sectional area of ​​which is constant in the direction of flow of the refrigerant, and a turbulent flow portion, the cross-sectional area of ​​which changes in the direction of flow of the refrigerant. [Effects of the Invention]

[0007] This configuration can improve the cooling efficiency. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 2 is a perspective view of the lower tray of the first embodiment as viewed obliquely from above. [Figure 2] FIG. 2 is a perspective view of the lower tray as viewed obliquely from below. [Figure 3] FIG. 2 is a perspective view of the lower tray in a disassembled state, seen obliquely from above. [Figure 4] FIG. 2 is a perspective view of the cooler in a disassembled state, seen obliquely from above. [Figure 5] FIG. 2 is a perspective view of the cooler in a disassembled state, seen obliquely from above. [Figure 6] FIG. 2 is a schematic plan view showing the configuration of a refrigerant flow path of a cooler. [Figure 7] 7 is a cross-sectional view of the cooler taken along line AA in FIG. 6. [Figure 8] 7 is a cross-sectional view of the lower tray taken along line BB in FIG. 6. [Figure 9] 7 is a cross-sectional view of the lower tray taken along line CC in FIG. 6. [Figure 10] 7 is a cross-sectional view of the lower tray taken along line DD in FIG. 6. [Figure 11] FIG. 10 is a schematic plan view showing the configuration of a refrigerant flow path of a cooler according to a second embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0009] [Description of the embodiments of the present disclosure] First, embodiments of the present disclosure will be listed and described. Any combination of the following embodiments without causing any contradiction is also included in the embodiments for carrying out the invention. The battery cooler of the present disclosure comprises: (1) A refrigerant case having a heat transfer section through which heat from a battery cell is transferred, and a refrigerant flow path formed within the refrigerant case and facing the heat transfer section, the refrigerant flow path being configured with a series of laminar flow sections with a constant cross-sectional area in the refrigerant flow direction and turbulent flow sections with a changing cross-sectional area in the refrigerant flow direction. According to the configuration of the present disclosure, a unidirectional flow of refrigerant is generated throughout the refrigerant flow path by the laminar flow sections. In the turbulent flow sections, turbulent flow of the refrigerant is generated by the change in cross-sectional area, so the amount of refrigerant that comes into contact with the heat transfer section per unit time is greater than in the laminar flow sections. Therefore, the cooling efficiency is superior to when the refrigerant flows laminarly throughout the entire refrigerant flow path.

[0010] (2) In (1), it is preferable that the turbulent flow section is formed by a single space communicating with the downstream ends of the parallel laminar flow sections. According to this configuration, a turbulent flow is generated in the turbulent flow section by the convergence of multiple refrigerant flows.

[0011] (3) In (2), it is preferable that the cross-sectional area of ​​the turbulent flow portion at the upstream end is larger than the total cross-sectional area of ​​the laminar flow portions. With this configuration, the refrigerant that flows from the laminar flow portions into the turbulent flow portion generates turbulence with its flow velocity suddenly reduced, thereby increasing the amount of heat transferred from the heat transfer portion to the refrigerant per unit time.

[0012] (4) In (1), it is preferable that the turbulent flow section is disposed between two of the laminar flow sections disposed in series in a straight line, and that the cross-sectional area of ​​the turbulent flow section is smaller than the cross-sectional area of ​​the laminar flow section. With this configuration, the inner surface of the turbulent flow section acts as a barrier to the refrigerant flowing into the turbulent flow section from the downstream end of the laminar flow section, thereby generating turbulence.

[0013] (5) In (1) to (4), it is preferable that the refrigerant case has a long and narrow partition that separates the parallel refrigerant flow paths, and that the turbulent flow section is formed by a widened portion of the partition that is locally enlarged in width. This configuration simplifies the structure of the refrigerant case compared to when the turbulent flow section is formed by a portion separate from the partition.

[0014] (6) In (5), it is preferable that the refrigerant case is configured by joining an outer peripheral edge of a first member having the heat transfer portion and an outer peripheral edge of a second member having the partition portion, and the partition portion is joined to the first member. With this configuration, the joining strength between the first member and the second member is higher than when the joining area between the first member and the second member is only the outer peripheral edge.

[0015] (7) In (5), it is preferable that the widened portion and the first member are fixed by spot welding. With this configuration, the widened portion has both the function of forming the turbulent flow portion and the function of fixing the partition portion to the first member, so the shape of the second member can be simplified compared to when the spot weld is formed separately from the widened portion.

[0016] [Details of the embodiments of the present disclosure] Example 1 A first embodiment of the present invention will be described below with reference to Figures 1 to 10. In the following description, the F direction in Figures 1 to 6 is defined as the front in terms of the front-rear direction. The H direction in Figures 1 to 5 and 7 to 10 is defined as the up direction in terms of the up-down direction. The R direction in Figures 1 to 10 is defined as the right direction in terms of the left-right direction. The left-right direction and the width direction are used synonymously.

[0017] 8, the battery case 10 of the first embodiment is a member having a function of cooling the battery cells 11, and is configured by assembling a lower tray 14 from below to an upper case 12. The interior of the battery case 10 functions as a battery accommodating space 13 for accommodating the battery cells 11.

[0018] The lower tray 14 includes a tray body 15 made of a single member, a plurality of battery coolers 30 (hereinafter referred to as "coolers 30") for cooling the battery cells 11, and a plurality of reinforcing members 20 for reinforcing the tray body 15. A single member is not a combination of multiple parts integrated by welding, bonding, or the like, but rather a single part molded in a form without seams or joints.

[0019] The tray body 15 is a part formed into a shallow rectangular dish shape by pressing a single metal plate. An alloy containing iron is used as the material for the tray body 15. The tray body 15 has a horizontal bottom plate portion 16 and a peripheral wall portion 17 that rises upward from the outer periphery of the bottom plate portion 16 along the entire periphery.

[0020] In a plan view of the tray main body 15 seen from above, the bottom plate portion 16 has a rectangular shape with its long sides facing in the left-right direction. The bottom plate portion 16 has a plurality of openings 18 (four in this embodiment 1). The openings 18 have a rectangular shape with their long sides facing in the front-rear direction. The four openings 18 are arranged side by side in the left-right direction. The openings 18 are openings that connect the space on the upper surface side of the bottom plate portion 16 (battery accommodating space 13) with the space on the lower surface side (outside of the battery case 10).

[0021] The peripheral wall 17 has a front plate 19F, a rear plate 19R, and a pair of left and right side plate portions 19S. The front plate 19F and the rear plate 19R are arranged along the long sides of the bottom plate 16. The left and right side plate portions 19S are arranged along the short sides of the bottom plate 16.

[0022] The reinforcing member 20 is a metal member parallel to the short sides of the tray main body 15. The reinforcing member 20 is joined by arc spot welding to the upper surface of the bottom plate portion 16 and to the inner surfaces of the front and rear plate portions 19F, 19R. The reinforcing member 20 is attached to the bottom plate portion 16 in the region between the adjacent openings 18 on the left and right. The reinforcing member 20 functions to increase the rigidity of the tray main body 15 and suppress relative displacement between the bottom plate portion 16 and the side plate portions 19S.

[0023] The cooler 30 is elongated in the front-rear direction and has a flat plate shape with a small height (thickness). Each cooler 30 has a refrigerant case 36 in which one upper plate 31 and one lower plate 40, which is a separate component from the upper plate 31, are stacked one on top of the other.

[0024] The upper plate 31 is a single component formed by pressing an aluminum or aluminum alloy plate. A cylindrical inlet port 32 protruding upward is provided at the rear end of the upper plate 31. A cylindrical outlet port 33 protruding upward is provided at the front end of the upper plate 31. The inlet port 32 and the outlet port 33 open on the lower surface of the upper plate 31. A heat transfer portion 34 is formed by recessing the lower surface of the upper plate 31 in the region of the upper plate 31 between the inlet port 32 and the outlet port 33. In a plan view of the cooler 30 seen from above, the heat transfer portion 34 is rectangular with its long sides oriented in the front-to-rear direction. The upper and lower surfaces of the heat transfer portion 34 are flat. The outer peripheral edge of the upper plate 31 is defined as a first flange portion 35.

[0025] The lower plate 40 is a single component formed by pressing a plate made of the same material as the upper plate 31, i.e., aluminum or aluminum alloy. Shallow recesses 41 are formed at both the front and rear ends of the upper surface of the lower plate 40. A plurality of elongated partitions 47, 48 extending in the front-rear direction are formed in the region of the upper surface of the lower plate 40 between the front and rear recesses 41. The partitions 47, 48 each have a rib-like shape that protrudes upward. The outer peripheral edge of the lower plate 40 is defined as a second flange 42.

[0026] The lower surface of the first flange portion 35 and the upper surface of the second flange portion 42 are liquid-tightly joined by a liquid sealing material (not shown) called a formed-in-place gasket (FIPG). The upper surfaces of the plurality of partition portions 47, 48 and the lower surface of the heat transfer portion 34 of the upper plate 31 are also liquid-tightly joined by a liquid sealing material. A pair of front and rear chambers 43 are formed between the lower surface of the upper plate 31 and the recess 41 of the lower plate 40. The rear chamber 43 is connected to the inlet port 32. The front chamber 43 is connected to the outlet port 33.

[0027] A refrigerant flow path 44 for flowing the refrigerant forward is formed within the refrigerant case 36 between the heat transfer portion 34 of the alignment plate and the upper surface of the lower plate 40. The unhatched areas in FIG. 6 represent the chamber 43 and the refrigerant flow path 44. The front and rear ends of the refrigerant flow path 44 are connected to both the front and rear chambers 43. The refrigerant flow path 44 is configured with a plurality of laminar flow sections 45 and a plurality of turbulent flow sections 46. The laminar flow sections 45 and the turbulent flow sections 46 are separated by a plurality of partition sections 47, 48. The partition sections 47, 48 include a first partition section 47 and a second partition section 48. In a plan view, all of the partition sections 47, 48 are located only within the area where the heat transfer portion 34 is formed.

[0028] The shape of the first partition 47 in a plan view is symmetrical both front to back and left to right. The first partition 47 is composed of a widened portion 47W located in the center in the front to back direction, a front constant-width portion 47F extending forward in a cantilevered manner from the widened portion 47W, and a rear constant-width portion 47R extending rearward in a cantilevered manner from the widened portion 47W. The widened portion 47W has a circular shape in a plan view whose diameter is larger than the width dimensions of both the front and rear constant-width portions 47F, 47R. At both left and right side edges of the first partition 47, the front and rear ends of the widened portion 47W and the constant-width portions 47F, 47R are smoothly connected.

[0029] The upper surface of the widened portion 47W and the lower surface of the heat transfer portion 34 of the upper plate 31 are fixed by spot welding in a heat transferable state. The widened portion 47W is wider than the front constant width portion 47F and the rear constant width portion 47R and has a circular shape as a whole, which ensures a wide contact area (facing area) with the heat transfer portion 34 and a high fixing strength by spot welding.

[0030] The second partition 48 has a constant width over its entire length. The width of the second partition 48 is the same as the width of the front constant width portion 47F and the rear constant width portion 47R. The length of the second partition 48 in the front-to-rear direction is the same as the length of the front constant width portion 47F and the rear constant width portion 47R.

[0031] As shown in FIG. 6 , within the refrigerant flow path 44, one row of partition walls 49 is formed by a plurality of partitions 47, 48 aligned in series at intervals in the front-to-rear direction. The plurality of rows of partition walls 49 are arranged in parallel with intervals in the left-to-right direction. In the odd-numbered rows of partition walls 49 counting from the front, second partitions 48 are arranged at the front and rear ends, and a plurality of first partitions 47 are arranged in series between the second partitions 48 at both the front and rear ends. In the even-numbered rows of partition walls 49 counting from the front, only a plurality of first partitions 47 are arranged in series, and no second partitions 48 are arranged. The plurality of first partitions 47 are arranged in a staggered pattern.

[0032] The refrigerant flow path 44 has a plurality of parallel laminar flow paths 45G and parallel turbulent flow paths 46G arranged alternately from the front end to the rear end. Each parallel laminar flow path 45G is formed by arranging a plurality of laminar flow sections 45 extending in the front-rear direction in parallel in the left-right direction. Each laminar flow section 45 is a space defined between a front constant width section 47F and a rear constant width section 47R arranged on the left and right, or between the constant width sections 47F, 47R and the side edges of the heat transfer section 34. Each laminar flow section 45 is a space in which the refrigerant flows in a laminar manner. When the refrigerant flow path 44 is cut perpendicular to the refrigerant flow direction (front-rear direction), the cross-sectional area of ​​each laminar flow section 45 is approximately constant from the upstream end (rear end) to the downstream end (front end) of the laminar flow section 45.

[0033] Each parallel turbulent flow path 46G is formed by arranging multiple turbulent flow sections 46 extending in the front-rear direction in parallel in the left-right direction. Each turbulent flow section 46 is a space partitioned between two adjacent widening sections 47W, or between the constant-width sections 47F, 47R and the side edge of the heat transfer section 34. Each turbulent flow section 46 is a space that allows the refrigerant to flow turbulently. When the refrigerant flow path 44 is cut perpendicular to the refrigerant flow direction (front-rear direction), the cross-sectional area of ​​each turbulent flow section 46 increases or decreases along the refrigerant flow path from the rear end to the front end of the turbulent flow section 46. The cross-sectional area of ​​each turbulent flow section 46 gradually decreases from the upstream end (rear end) of the turbulent flow section 46 to the center in the front-rear direction of the turbulent flow section 46. The cross-sectional area of ​​each turbulent flow section 46 gradually increases from the center in the front-rear direction of the turbulent flow section 46 to the downstream end (front end).

[0034] The upstream end (rear end) of each laminar flow section 45 of the parallel laminar flow passage 45G located at the upstream end (rearmost end) is connected to the rear chamber 43. The downstream end of each laminar flow section 45 of the parallel laminar flow passage 45G other than the downstream end (forward end) is connected to the upstream end (rear end) of the turbulent flow section 46. More specifically, the downstream ends of two laminar flow sections 45 arranged side by side are connected to the upstream end (rear end) of one turbulent flow section 46. In the connecting portion from the downstream ends of the two laminar flow sections 45 arranged side by side to the upstream end of one turbulent flow section 46, the cross-sectional area of ​​the upstream end of one turbulent flow section 46 is larger than the combined cross-sectional area of ​​the two laminar flow sections 45. The downstream end (front end) of one turbulent flow section is connected to the upstream ends (rear ends) of the two laminar flow sections 45 adjacent to each other on the left and right. At the connection portion from the downstream end of one turbulent flow section 46 to the upstream ends of the two laminar flow sections 45 lined up on the left and right, the cross-sectional area of ​​the downstream end of one turbulent flow section 46 is larger than the total cross-sectional area of ​​the two laminar flow sections 45. The downstream ends (front ends) of each laminar flow section 45 of the parallel laminar flow path 45G located at the downstream end (front end) are connected to the front chamber 43.

[0035] The cooler 30 is attached to the lower surface (outer surface) of the tray main body 15. In detail, the upper surface of the cooler 30 (first flange portion 35) and the opening edge portion of the opening 18 on the lower surface of the tray main body 15 (bottom plate portion 16) are liquid-tightly joined by a liquid sealing material (not shown). When the cooler 30 is attached to the tray main body 15, the joint portion (first flange portion 35 and second flange portion 42) between the lower plate 40 and the upper plate 31 is located outside (below) the tray main body 15. In addition, in a plan view, the heat transfer portion 34 is disposed within the opening 18. A heat transfer sheet (not shown) is disposed on the upper surface of the heat transfer portion 34 to effectively remove heat from the lower surfaces of the battery cells 11.

[0036] The refrigerant (cooling liquid) supplied to the cooler 30 from the inlet port 32 passes through the rear chamber 43 and the inside of the refrigerant flow path 44, passes through the front chamber 43, and is discharged from the outlet port 33. As the refrigerant passes through the refrigerant flow path 44, the refrigerant that has passed through adjacent laminar flow sections 45 on the left and right join at the downstream ends of the laminar flow sections 45 and flows into the upstream end of one turbulent flow section 46. The refrigerant that has passed through one turbulent flow section 46 splits into left and right flows at the downstream end of the turbulent flow section 46 and flows into the upstream ends of the two laminar flow sections 45. As the refrigerant passes through the laminar flow sections 45 and turbulent flow sections 46, it comes into contact with the heat transfer section 34 and removes heat from the battery cells 11 via the heat transfer section 34.

[0037] The laminar flow section 45 of the refrigerant flow path 44 is a flow path with a constant cross-sectional area from the upstream end to the downstream end. The side surfaces of the constant width sections 47F, 47R that form the left and right sides of the laminar flow section 45 are formed by flat surfaces extending in the front-to-rear direction. Therefore, the refrigerant flows in a laminar (linear) manner within the laminar flow section 45, and only a portion of the refrigerant passing through the laminar flow section 45 comes into contact with the heat transfer section 34.

[0038] The height of the turbulent flow section 46 of the refrigerant flow path 44 is constant throughout the entire region from the upstream end to the downstream end. The widened portions 47W that form the left and right sides of the turbulent flow section 46 have curved sides. The width of the turbulent flow section 46 gradually narrows from the upstream end of the turbulent flow section 46 to the center in the flow direction, and gradually increases from the center in the flow direction to the downstream end of the turbulent flow section 46. Therefore, the cross-sectional area of ​​the turbulent flow section 46 gradually decreases from the upstream end to the center in the flow direction, and gradually increases from the center in the flow direction to the downstream end.

[0039] As described above, the turbulent flow section 46 is a flow path whose cross-sectional area changes from the upstream end to the downstream end, so the refrigerant in the turbulent flow section 46 does not flow in a straight line but rather swirls and turns irregularly in the up, down, left, and right directions. As a result, the refrigerant passes through the turbulent flow section 46 in a turbulent state, so that most of the refrigerant passing through the turbulent flow section 46 can come into contact with the heat transfer section 34. Therefore, the amount of heat transferred from the heat transfer section 34 to the refrigerant in the turbulent flow section 46 is greater than the amount of heat transferred from the heat transfer section 34 to the refrigerant in the laminar flow section 45.

[0040] The cooler 30 of the first embodiment has a refrigerant case 36 and a refrigerant flow path 44. The refrigerant case 36 has a heat transfer portion 34 to which heat from the battery cells 11 is transferred. The refrigerant flow path 44 is formed within the refrigerant case 36 and faces the heat transfer portion 34. The refrigerant flow path 44 is configured by connecting a laminar flow portion 45, which has a constant cross-sectional area in the flow direction of the refrigerant, and a turbulent flow portion 46, which has a cross-sectional area that changes in the flow direction of the refrigerant. With this configuration, the laminar flow portion 45 generates a unidirectional flow of the refrigerant throughout the refrigerant flow path 44. In the turbulent flow portion 46, a turbulent flow of the refrigerant is generated due to the change in cross-sectional area, so the amount of refrigerant that comes into contact with the heat transfer portion 34 per unit time is greater than in the laminar flow portion 45. Therefore, the cooling efficiency is superior to when the refrigerant flows laminarly throughout the entire region of the refrigerant flow path 44.

[0041] The turbulent flow section 46 is formed by a single space that communicates with the downstream ends of the plurality of parallel-arranged laminar flow sections 45. According to this configuration, in the turbulent flow section 46, a turbulent flow is generated by the convergence of the plurality of refrigerant flows.

[0042] The cross-sectional area at the upstream end of one turbulent flow section 46 is larger than the total cross-sectional area of ​​the two (plural) laminar flow sections 45 adjacent to each other on the left and right. With this configuration, the refrigerant that flows into the turbulent flow section 46 from the laminar flow sections 45 generates a turbulent flow with its flow velocity suddenly reduced, thereby increasing the amount of heat transferred from the heat transfer section 34 to the refrigerant per unit time.

[0043] Refrigerant case 36 has a long and narrow first partition section 47 that separates parallel refrigerant flow paths 44. Widened sections 47W of first partition section 47, which have a locally increased width, form turbulent section 46. This configuration simplifies the structure of refrigerant case 36 compared to when turbulent section 46 is formed in a location separate from partition sections 47, 48.

[0044] The refrigerant case 36 is configured by joining a first flange portion 35, which is the outer peripheral edge portion of the upper plate 31 having the heat transfer portion 34, and a second flange portion 42, which is the outer peripheral edge portion of the lower plate 40, on which the first partition portion 47 and the second partition portion 48 are formed. The first partition portion 47 and the second partition portion 48 are joined to the lower surface of the heat transfer portion 34 of the upper plate 31. With this configuration, the joining strength is higher than when the joining area between the upper plate 31 and the lower plate 40 is only the outer peripheral edge portions (the first flange portion 35 and the second flange portion 42).

[0045] The upper surface of the wide widened portion 47W of the first partition 47 and the lower surface of the heat transfer portion 34 of the upper plate 31 are fixed by spot welding in a heat transferable state. This welding structure prevents the heat transfer portion 34 and the first partition 47 from separating from each other even when the internal pressure of the refrigerant flow path 44 increases. This maintains a stable laminar flow of the refrigerant and an efficient cooling effect (heat transfer effect) due to the turbulent flow within the refrigerant flow path 44. The widened portion 47W combines the function of forming the turbulent flow portion 46 and the function of fixing the first partition 47 to the upper plate 31. Therefore, the shape of the lower plate 40 can be simplified compared to when a spot weld is formed on the lower plate 40 separately from the widened portion 47W.

[0046] <Example 2> Next, a second embodiment of the present invention will be described with reference to FIG. 11. In this second embodiment, the front-rear direction is defined as the F direction in FIG. 11. The left-right direction is defined as the R direction in FIG. 11. The left-right direction and the width direction are used synonymously. A cooler 50 in this second embodiment has a refrigerant flow path 51 configured differently from that in the first embodiment. Since the other configurations are the same as those in the first embodiment, the same components are denoted by the same reference numerals, and descriptions of the structure, operation, and effects will be omitted.

[0047] The cooler 50 of the second embodiment is formed with a refrigerant flow path 51 that communicates with both the front and rear chambers 43. In addition, the non-hatched areas in Fig. 11 represent the chambers 43 and the refrigerant flow path 51. The configuration of the upper plate 31 is the same as that of the upper plate 31 of the first embodiment.

[0048] A pair of front and rear recesses 53 that form the chamber 43, and multiple partitions 54, 55 that form the refrigerant flow path 51 are formed in the lower plate 52. The multiple partitions 54, 55 include an odd number of first partitions 54 and an even number of second partitions 55. The first partitions 54 and the second partitions 55 are both linear portions that extend continuously from the upstream end to the downstream end of the refrigerant flow path 51 and protrude upward like a rib from the lower plate 52. The multiple first partitions 54 and the multiple second partitions 55 are arranged in parallel and alternately spaced apart from one another on the left and right.

[0049] The first partition 54 is formed with a plurality of first widened portions 54W spaced apart in the front-to-rear direction (the direction of refrigerant flow). The portion of the first partition 54 other than the first widened portions 54W is defined as a first constant width portion 54C that has a constant width and is narrower than the first widened portions 54W. The second partition 55 is formed with a plurality of second widened portions 55W spaced apart in the front-to-rear direction (the direction of refrigerant flow). The portion of the second partition 55 other than the second widened portions 55W is defined as a second constant width portion 55C that has a constant width and is narrower than the second widened portions 55W. In a plan view, the plurality of first widened portions 54W and the plurality of second widened portions 55W are arranged in a staggered pattern.

[0050] The upper surface of the first widened portion 54W of the first partition 54 and the upper surface of the second widened portion 55W of the second partition 55 are fixed to the lower surface of the heat transfer portion 34 of the upper plate 31 by spot welding in a heat transferable state. This welding structure prevents the heat transfer portion 34 from being separated from the first partition 54 and the heat transfer portion 34 from being separated from the second partition 55, even if the internal pressure of the refrigerant flow path 51 increases. This maintains an efficient cooling effect (heat transfer effect) due to a stable laminar flow of the refrigerant and a turbulent flow within the refrigerant flow path 51.

[0051] The refrigerant flow path 51 is made up of multiple parallel flow paths 56 arranged in parallel with a gap between them on the left and right. One parallel flow path 56 is a space defined between adjacent first partitions 54 and second partitions 55, or between a first partition 54 and a side edge of the heat transfer section 34. One parallel flow path 56 is made up of multiple laminar flow sections 57 and multiple turbulent flow sections 58 arranged alternately in series in the front-to-rear direction.

[0052] The laminar flow section 57 is a flow path partitioned between the first constant width section 54C and the second constant width section 55C adjacent to each other on the left and right, or between the first constant width section 54C and the side edge of the heat transfer section 34. Each laminar flow section 57 is a space that allows the refrigerant to flow in a laminar flow. The cross-sectional area of ​​the laminar flow section 57 is approximately constant from the upstream end to the downstream end of the laminar flow section 57. Multiple laminar flow sections 57 are arranged in parallel on the left and right at the upstream and downstream ends of the refrigerant flow path 51. The upstream end of the laminar flow section 57 arranged at the upstream end is connected to the rear chamber 43. The downstream end of the laminar flow section 57 arranged at the downstream end is connected to the front chamber 43.

[0053] The turbulent flow section 58 is a flow path defined between the first widened portion 54W and the second constant width portion 55C, between the second widened portion 55W and the first constant width portion 54C, or between the first widened portion 54W and the side edge of the heat transfer section 34. Each turbulent flow section 58 is a space that allows the refrigerant to flow turbulently. In each parallel flow path 56, the cross-sectional area of ​​the turbulent flow section 58 is smaller than the cross-sectional area of ​​the laminar flow section 57 that communicates with that turbulent flow section 58. The cross-sectional area of ​​the turbulent flow section 58 increases and decreases along the refrigerant flow path from the rear end to the front end of the turbulent flow section 58. The cross-sectional area of ​​the turbulent flow section 58 gradually decreases from the upstream end (rear end) of the turbulent flow section 58 to the center in the front-rear direction of the turbulent flow section 58. The cross-sectional area of ​​the turbulent flow section 58 gradually increases from the center in the front-rear direction of the turbulent flow section 58 to the downstream end (front end).

[0054] The refrigerant (cooling liquid) supplied to the cooler 50 from the inlet port 32 passes through the rear chamber 43 and the inside of the refrigerant flow path 51, passes through the front chamber 43 and is discharged from the outlet port 33. In the process of the refrigerant passing through the refrigerant flow path 51, the refrigerant removes heat from the battery cells 11 (not shown) by coming into contact with the heat transfer portion 34. In the laminar flow portion 57, the refrigerant flows in a laminar flow (linearly), and therefore, only a portion of the refrigerant passing through the laminar flow portion 57 comes into contact with the heat transfer portion 34.

[0055] The turbulent flow section 58 is disposed between two laminar flow sections 57 arranged in series in a straight line. The cross-sectional area of ​​the turbulent flow section 58 is smaller than that of the laminar flow section 57. With this configuration, the inner surface at the upstream end of the turbulent flow section 58 acts as a barrier to the refrigerant that flows into the turbulent flow section 58 from the downstream end of the laminar flow section 57. This barrier creates a turbulent flow of the refrigerant within the turbulent flow section 58. Within the turbulent flow section 58, the refrigerant flows turbulently, swirling and turning irregularly up, down, left, and right, allowing most of the refrigerant to come into contact with the heat transfer section 34. Therefore, the amount of heat transferred from the heat transfer section 34 to the refrigerant in the turbulent flow section 58 is greater than the amount of heat transferred from the heat transfer section 34 to the refrigerant in the laminar flow section 57.

[0056] The first widened portion 54W and the second widened portion 55W have the function of forming the turbulent flow portion 58 and the function of fixing the first partition portion 54 and the second partition portion 55 to the upper plate 31. Therefore, the shape of the lower plate 52 can be simplified compared to when spot welds are formed in the lower plate 52 separately from the first widened portion 54W and the second widened portion 55W.

[0057] <Other Examples> The present invention is not limited to the embodiments described above and illustrated in the drawings, and the following embodiments are also included within the technical scope of the present invention. In the first embodiment, the cross-sectional area of ​​the upstream end of the turbulent flow section may be the same as the total cross-sectional area of ​​the plurality of laminar flow sections. In Example 1-2, the turbulent flow section may be formed by a portion other than the partition section. In Example 1-2, the joining region between the upper plate (first member) and the lower plate (second member) may be limited to the first flange portion (outer peripheral edge portion) and the second flange portion (outer peripheral edge portion). [Explanation of symbols]

[0058] 11...Battery cell 30,50...Cooler (battery cooler) 31...Upper plate (first member) 34...Heat transfer section 35...First flange portion (outer peripheral edge portion of upper plate) 36...Refrigerant case 40, 52...Lower plate (second member) 42...Second flange portion (outer peripheral edge portion of lower plate) 44, 51... Refrigerant flow path 45,57…Laminar flow part 46,58...Turbulent section 47,55...First partition (partition) 47W…Wide section 48, 56...Second partition (partition) 54W...First widening section 55W...Second widening section

Claims

1. a refrigerant case having a heat transfer portion to which heat from the battery cell is transferred; a refrigerant flow path formed in the refrigerant case and facing the heat transfer portion, The refrigerant flow path of the battery cooler is configured by connecting a laminar flow section whose cross-sectional area is constant in the flow direction of the refrigerant and a turbulent flow section whose cross-sectional area changes in the flow direction of the refrigerant.

2. 2. The battery cooler according to claim 1, wherein the turbulent flow section is formed by a single space communicating with downstream ends of a plurality of the laminar flow sections that are parallel to one another.

3. The battery cooler according to claim 2 , wherein a cross-sectional area of ​​the turbulent flow portion at an upstream end thereof is larger than a total cross-sectional area of ​​the plurality of laminar flow portions.

4. the turbulent flow section is disposed between two of the laminar flow sections that are arranged in series in a straight line, 2. The battery cooler according to claim 1, wherein the cross-sectional area of ​​the turbulent flow section is smaller than the cross-sectional area of ​​the laminar flow section.

5. the refrigerant case has an elongated partition portion that separates the parallel refrigerant flow paths, 5. The battery cooler according to claim 1, wherein the turbulent flow portion is formed by a widened portion of the partition portion, the widened portion having a locally increased width.

6. the refrigerant case is configured by joining an outer peripheral edge portion of a first member having the heat transfer portion and an outer peripheral edge portion of a second member having the partition portion formed therein, The battery cooler according to claim 5, wherein the partition portion is joined to the first member.

7. The battery cooler according to claim 5, wherein the widened portion and the first member are fixed to each other by spot welding.

Images