Battery cooler

Abstract

A battery cooler according to the present disclosure includes a supply flow path (21), a branch flow path (30), and a discharge flow path (22), and is configured such that: a corner part (C) of the battery cooler (1) is provided with an extension part (40) formed by joining a first plate-like member (10) and a second plate-like member (20), the extension part (40) extending adjacent to the outside of a bent part (L) formed by a downstream-side terminal end of the supply flow path (21) and an inflow port (310); and at least a part of the branch flow path (30) is disposed so as to pass through the extension part (40).

Description

Battery cooler

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

[0002] Patent Document 1 discloses a heat exchange device used for cooling a battery, which includes an inflow duct, an outflow duct, and a lateral duct connecting between the inflow duct and the outflow duct.

[0003] Japanese Patent Publication No. 2016-506030

[0004] However, in the heat exchange device described in Patent Document 1, there is room for improvement in the cooling efficiency in terms of the connection part, arrangement, and duct shape of the inflow duct and the lateral duct.

[0005] An aspect of the present disclosure aims to realize a battery cooler that can cool battery cells more uniformly than before.

[0006] In order to solve the above problems, the battery cooler according to the present disclosure is a battery cooler including a first plate-like member, a second plate-like member, and a flow path formed by joining the first plate-like member and the second plate-like member for allowing a refrigerant to flow through. The flow path includes a supply flow path for supplying the refrigerant, a branch flow path having an inlet connected to the supply flow path and for allowing the refrigerant branched from the supply flow path and supplied through the inlet to flow through, and a discharge flow path connected to the branch flow path and for allowing the discharged refrigerant to flow through. The battery cooler includes an extending portion formed by joining the first plate-like member and the second plate-like member, and at a corner of the battery cooler, there is provided an extending portion that extends adjacent to the outside of a bent portion formed by a downstream end of the supply flow path and the inlet along the refrigerant flow direction in the supply flow path, and at least a part of the branch flow path is arranged to pass through the extending portion.

[0007] According to an aspect of the present disclosure, a battery cooler that can cool battery cells more uniformly than before can be provided.

[0008] This is a perspective view showing the external appearance of a battery cooler according to an embodiment of the present disclosure. This figure shows a plan view of the first plate-shaped member and the second plate-shaped member constituting the battery cooler according to an embodiment of the present disclosure. This is a side view showing the state in which the first plate-shaped member and the second plate-shaped member according to an embodiment of the present disclosure are joined together. This is an enlarged view of the dashed-line framed portion B shown in Figure 2, showing the state as seen through the supply channel, branch channel, and discharge channel, and illustrating the direction of refrigerant flow within the branch channel. This is a partially enlarged cross-sectional view taken along the line X-X shown in Figure 2. This is a plan view of the battery cooler according to an embodiment of the present disclosure, viewed from below, and a partially enlarged view of the dashed-line framed portion C in the plan view. This is a simplified schematic diagram of the corner C in Figure 6. This is a plan view of the dashed-line framed portion A shown in Figure 2, viewed from below, and is a partially cross-sectional view taken by cutting the discharge channel horizontally. These are partially enlarged cross-sectional views taken along the lines D-D, E-E, F-F, and G-G shown in Figure 8.

[0009] An embodiment of this disclosure will be described in detail below. For the sake of explanation, the up-down direction, left-right direction, and front-back direction will be defined as shown by the arrows in each figure below. The left-right direction and the front-back direction may also be referred to as the horizontal direction. However, it should be noted that these directions are used to indicate the relative positional relationship in one state, and the relative positional relationship may change depending on the installation direction of the battery cooler 1.

[0010] In this disclosure, "battery" is not limited to lithium-ion batteries, but may include other batteries such as nickel-metal hydride batteries and sodium-ion batteries.

[0011] Furthermore, the shape of the "battery cell" may be changed as appropriate to match the shape of the battery cooler 1, such as prismatic, cylindrical, pouch-type, or blade-type. The "battery cell" can be installed in hybrid electric vehicles (HEVs), plug-in hybrid electric vehicles (PHEVs), and electric vehicles (BEVs), etc. However, the use of the "battery cell" is not limited to automotive applications.

[0012] (Overview of the Battery Cooler) The overview of the battery cooler 1 will be explained in detail using Figures 1 to 3. Figure 1 is a perspective view showing the external appearance of the battery cooler 1. Figure 2 is a plan view showing the first plate-shaped member 10 and the second plate-shaped member 20 that constitute the battery cooler 1. Figure 3 is a side view showing the state in which the first plate-shaped member 10 and the second plate-shaped member 20 are joined together.

[0013] The battery cooler 1 is designed to be separate from the battery cells and the case that houses the battery cells, for example, in an electric vehicle. The battery cooler 1 is used in contact with the back surface of the case that houses the battery cells, specifically the surface on which the battery cells are mounted. As shown in Figures 1 to 3, the battery cooler 1 is substantially rectangular in plan view and comprises a first plate-shaped member 10 and a second plate-shaped member 20. The first plate-shaped member 10 and the second plate-shaped member 20 are joined together, for example, by laser welding. However, the joining means is not limited to laser welding; other welding means such as TIG welding, brazing means such as soldering, etc., may also be used.

[0014] When the first plate-shaped member 10 and the second plate-shaped member 20 are joined together, a flow path 100 for circulating the refrigerant is formed, and the internal space of the flow path 100 can be made liquid-tight. In other words, the inner wall of the flow path 100 is composed of a part of the first plate-shaped member 10 and a part of the second plate-shaped member 20.

[0015] Furthermore, the shape of the battery cooler 1 is not limited to a roughly rectangular shape in plan view, and may be appropriately molded to match the shape of the battery cell it is in contact with. Also, although the battery cooler 1 is described in this embodiment as being for cooling the battery cell, it is not limited to this, and may also be configured to heat the battery cell.

[0016] (First plate-shaped member) The first plate-shaped member 10 is a thin plate that is substantially rectangular in plan view and is positioned opposite the second plate-shaped member 20. As shown in Figures 1 and 2, the first plate-shaped member 10 includes a receiving groove 11 that is molded to accommodate the branching channel 30, which will be described later, a refrigerant inlet 12, and a refrigerant outlet 13.

[0017] The first plate-shaped member 10 has, for example, a joining region with the second plate-shaped member provided at the periphery of the first plate-shaped member 10 and between the multiple receiving grooves 11, and the two plates are joined by laser joining of the joining region.

[0018] Multiple storage grooves 11 are provided; in this embodiment, four are provided, but the number is not limited to the above number and may be provided in accordance with the number of branching channels 30. For example, if there is one branching channel 30, one groove may suffice. The refrigerant inlet 12 is an inlet for introducing refrigerant to be circulated in the battery cooler 1. The refrigerant outlet 13 is an outlet for discharging the refrigerant that has been circulated in the battery cooler 1 to the outside of the battery cooler 1.

[0019] (Second plate-shaped member) The second plate-shaped member 20 is a thin plate that is substantially rectangular in plan view and is positioned opposite the first plate-shaped member 10. As shown in Figure 2, the second plate-shaped member 20 is equipped with a supply channel 21, a discharge channel 22, and a branch channel 30.

[0020] The second plate-shaped member 20 only needs to have a joining region provided at a position corresponding to the joining region provided on the first plate-shaped member 10, and the joining region is joined by laser welding. The joining region on the second plate-shaped member 20 may be provided, for example, at the periphery of the second plate-shaped member 20 or between the multiple branched channels 30.

[0021] The first plate-shaped member 10 and the second plate-shaped member 20 are formed from a material with excellent weldability and durability, such as stainless steel (SUS). However, the material of the first plate-shaped member 10 and the second plate-shaped member 20 is not limited to stainless steel; they may also be formed from a material with high thermal conductivity, such as aluminum.

[0022] (Flow path) As shown in Figure 2, the flow path 100 is composed of a supply flow path 21, a branch flow path 30, and a discharge flow path 22. The flow path 100 is a path for circulating refrigerant in the direction from the refrigerant inlet 12 to the refrigerant outlet 13, that is, in the direction in which refrigerant flows from the upstream side to the downstream side (hereinafter also referred to as the refrigerant flow direction).

[0023] The flow path 100 plays a role in exchanging heat generated from the battery cells with a coolant, and by circulating the coolant along the flow path 100, it dissipates heat from the battery cells and suppresses the temperature rise of the battery cells.

[0024] (Supply channel) The supply channel 21 is the path for supplying refrigerant. Specifically, the supply channel 21 is responsible for supplying the refrigerant introduced from the refrigerant inlet 12 to the channel 100, and the refrigerant flows into the branch channel 30 via the supply channel 21.

[0025] (Branching channel) As shown in Figure 2, the branching channel 30 has an inlet 310 connected to the supply channel 21 in a direction intersecting the refrigerant flow direction in the supply channel 21, and is a path through which the refrigerant branched off from the supply channel 21 via the inlet 310 flows.

[0026] The refrigerant that flows into the branch channel 30 flows meanderingly through the inside of the branch channel 30 along the direction of refrigerant flow, and then the refrigerant is circulated from the downstream end of the branch channel 30 to the discharge channel 22, which will be described later. In other words, the branch channel 30 plays the role of a connecting path between the supply channel 21 and the discharge channel 22.

[0027] Here, the details of the branch channel 30 will be explained using Figures 4 and 5. Figure 4 is an enlarged view of the area enclosed by the dashed line frame B shown in Figure 2, showing the state after passing through the supply channel 21, branch channel 30, and discharge channel 22, and is a diagram showing the direction of refrigerant flow within the branch channel 30. Figure 5 is a partially enlarged cross-sectional view taken along the line X-X shown in Figure 2.

[0028] As shown in Figures 4 and 5, the branched flow path 30 comprises a plurality of parallel flow paths arranged in parallel. Each of the plurality of parallel flow paths is composed of a first feed flow path 31, a return flow path 32, and a second feed flow path 33. The refrigerant flowing to the battery cooler 1 circulates inside the flow path 100 in the order of (1) to (6) shown in Figure 4.

[0029] In detail, (1) the refrigerant introduced from the refrigerant inlet 12 flows through the supply channel 21 along the direction of refrigerant flow.

[0030] (2) The refrigerant flowing inside the supply channel 21 flows into the first supply channel 31 via the inlet 310. In other words, the inlet 310 is provided at the upstream end of the first supply channel 31. The first supply channel 31 is a path for circulating the refrigerant from the front to the back of the battery cooler 1.

[0031] (3) The refrigerant that has reached the downstream end of the first supply channel 31 flows through the first return channel R1, which is shaped so that the refrigerant branches off and flows in a direction intersecting the direction of refrigerant flow, and then flows into the return channel 32. The first return channel R1 is shaped in a roughly T-shape. The first return channel R1 is shaped so that the refrigerant flowing in from the first supply channel 31 hits a wall at the intersection of the first return channel R1 and the first supply channel 31, and the flow of refrigerant branches off to the left and right. The return channels 32 are connected to the left and right ends of the first return channel R1. In other words, the first return channel R1 plays the role of a connecting channel that connects the ends of the first supply channel 31 and the return channel 32.

[0032] (4) The refrigerant that flows in from the first return flow path R1 flows through the return flow paths 32, which are provided in the left and right directions along the direction of refrigerant flow. The return flow paths 32 are paths that circulate the refrigerant from the rear to the front of the battery cooler 1.

[0033] (5) The refrigerant that has reached the downstream end of the return channel 32 flows to the second supply channel 33 via the second return channel R2, which is shaped so that the refrigerant flows in a direction intersecting the direction of refrigerant flow. The second return channel R2 is shaped in a roughly U-shape. The second return channel R2 is shaped so that the refrigerant flowing in from the return channel 32 hits a wall at the intersection of the second return channel R2 and the return channel 32, and flows along the direction of refrigerant flow. The second return channel R2 plays the role of a connecting channel that connects the ends of the return channel 32 and the second supply channel 33.

[0034] (6) The downstream end of the second supply channel 33 is connected to the discharge channel 22, which will be described later, and the refrigerant flowing through the inside of the second supply channel 33 along the direction of refrigerant flow flows into the discharge channel 22.

[0035] The battery cooler 1 is equipped with multiple branching channels 30, and the refrigerant flows in the same order as (1) to (6) described above.

[0036] Furthermore, the branched flow path 30 has a characteristic shape for increasing the flow velocity of the refrigerant circulating inside it. This characteristic shape will be described in detail with reference to Figure 5. As shown in Figure 5, at least one of the first supply flow path 31, return flow path 32, and second supply flow path 33, which constitute a plurality of parallel flow paths, is provided with a recessed portion 320. The recessed portion 320 is formed by recessing the central part of the parallel flow path in a cross-sectional view perpendicular to the refrigerant flow direction from the outside (bottom) to the inside (top) of the flow path 100.

[0037] As shown in Figure 5, the recessed portion 320 is formed into a curved shape. However, it is not limited to this, and the recessed portion 320 may be formed into a shape that combines straight lines in an uneven manner. Also, the curved surface of the recessed portion 320 may be formed into a wavy shape composed of multiple waves. In this embodiment, the recessed portion 320 is provided in the return channel 32.

[0038] In detail, the recessed portion 320 is formed such that the cross-sectional area of ​​the end channels 321 at both ends of the return channel 32 is larger than the cross-sectional area of ​​the channel in the central portion (recessed portion 320), with the central portion (recessed portion 320) in between.

[0039] Thus, the return flow path 32 has a recessed portion 320 and an end flow path 321. As a result, the cross-sectional area of ​​the flow path in the portion with the recessed portion 320 is reduced, while the cross-sectional area of ​​the flow path in the end flow path 321 is increased. Consequently, the flow velocity of the refrigerant slows down and the flow rate decreases in the portion with the recessed portion 320. Conversely, the flow velocity of the refrigerant increases and the flow rate increases in the end flow path 321. As a result, the cooling efficiency in the end flow path 321 is improved.

[0040] Furthermore, the configuration is not limited to the return channel 32 having a recessed portion 320; the first feed channel 31 may also have a recessed portion 320, the second feed channel 33 may also have a recessed portion 320, or all of the parallel channels may also have recessed portions 320.

[0041] As described above, when the flow velocity of the refrigerant flowing through the end flow path 321 increases and the flow rate increases, the temperature of the portion close to or in contact with the end flow path 321 can be efficiently reduced. The portion close to or in contact with the end flow path 321 is a portion (hereinafter referred to as the joint portion W) where the first plate-like member 10 and the second plate-like member 20 are joined, which is between a plurality of parallel flow paths (the first feed flow path 31, the return flow path 32, and the second feed flow path 33) indicated by the broken line frame W in FIG. 5. Therefore, for example, even when the battery cells are in contact with the upper surface side of the battery cooler 1, specifically, the entire upper surface of the accommodation groove 11, the temperature of the joint portion W can be efficiently reduced, and the entire surface of the battery cells can be uniformly cooled.

[0042] Furthermore, the branch flow path 30 is configured by a characteristic flow path arrangement for making it difficult for the heat of the battery cells to accumulate in the vicinity of the downstream end of the supply flow path 21 where the heat of the battery cells generally tends to accumulate in the flow path 100 of the battery cooler 1. The characteristic flow path arrangement will be described in detail with reference to FIGS. 6 and 7. FIG. 6 is a plan view of the battery cooler 1 viewed from below and a partial enlarged view of the portion surrounded by the broken line frame C in the plan view. The surrounded portion C is an example of a corner portion of the battery cooler 1 (hereinafter referred to as the corner portion C). FIG. 7 is a schematic diagram obtained by simplifying the corner portion C in FIG. 6.

[0043] As shown in FIGS. 6 and 7, a bent portion L formed by the downstream end of the supply flow path 21 and the inlet 310 is provided at the connection portion between the downstream end of the supply flow path 21 and the branch flow path 30. By providing the bent portion L, at the downstream end of the supply flow path 21, the refrigerant flowing inside the supply flow path 21 is smoothly guided to the branch flow path 30 along the inner wall of the bent portion L. Therefore, at the downstream end of the supply flow path 21, the cooling efficiency of the corner portion C can be improved without the refrigerant staying.

[0044] (Extension portion) Furthermore, an extension portion 40 that extends adjacent to the bent portion L is provided at the corner portion C of the battery cooler 1 on the outer side (right side) of the bent portion L.

[0045] The extending portion 40 is an area provided in the portion shown by the broken line frame D shown in FIGS. 6 and 7, and is formed in a range where the supply channel 21 is not provided. That is, the supply channel 21 is not provided in the extending portion 40. Specifically, the extending portion 40 is formed by joining the first plate-like member 10 and the second plate-like member 20, and at least a part of the branch channel 30 is arranged to pass through the extending portion 40.

[0046] In the present embodiment, among the four branch channels 30 provided in the battery cooler 1, one branch channel 30 connected to the bent portion L is arranged such that at least a part of it passes through the extending portion 40. Therefore, the length in the front-rear direction of the parallel channels arranged to pass through the extending portion 40 is longer than the lengths of the parallel channels provided in the other three branch channels 30.

[0047] At least a part of the branch channel 30 is, as shown in FIGS. 6 and 7, the second return channel R2 that connects the ends of the return channel 32 and the second feed channel 33. As shown in FIG. 7, the front edge of the second return channel R2 extends to a position adjacent in the left-right direction to the front edge of the supply channel 21. However, it is not essential for the front edge of the second return channel R2 to extend to an adjacent position, and the front edge of the second return channel R2 may be arranged on the rear side in the front-rear direction. The front edge of the second return channel R2 only needs to pass through the extending portion 40.

[0048] Thus, by arranging the second return channel R2 to pass through the extending portion 40, the cooling efficiency of the corner portion C and the area where the extending portion 40 is provided can be improved.

[0049] Therefore, even when a battery cell is arranged at a position corresponding to the corner portion C on the upper surface of the accommodation groove 11, heat exchange of the corner portion C can be efficiently performed, so that the entire surface of the battery cell can be cooled uniformly.

[0050] (Discharge channel) As explained above, the refrigerant that has flowed through the multiple branch channels 30 flows from the second supply channel 33 to the discharge channel 22. The discharge channel 22 is connected to the branch channels 30 and plays the role of circulating the refrigerant to be discharged to the outside of the battery cooler 1.

[0051] Details of the discharge channel 22 will be explained using Figure 8. Figure 8 is a plan view of the dashed-line framed area A shown in Figure 2, viewed from below, and is a partial cross-sectional view of the discharge channel 22 cut horizontally. As shown in Figure 8, the discharge channel 22 has, in order from the upstream side (right side) to the downstream side (left side), a first discharge channel 221, a second discharge channel 222, and a third discharge channel 223 (hereinafter, when referring to the discharge channel 22, it includes the first discharge channel 221, the second discharge channel 222, and the third discharge channel 223).

[0052] The first discharge channel 221, the second discharge channel 222, and the third discharge channel 223 each serve as connecting paths that link multiple branch channels 30 together. The lightly shaded areas in Figure 8 show cross-sections of the first discharge channel 221, the second discharge channel 222, and the third discharge channel 223. In other words, they show the respective compartmentalized areas of the first discharge channel 221, the second discharge channel 222, and the third discharge channel 223 are shaped so that the flow path length in the refrigerant flow direction increases in the order of the first discharge channel 221, the second discharge channel 222, and the third discharge channel 223.

[0053] In this embodiment, the discharge channel 22 is formed such that, in the refrigerant flow direction, the volume of the discharge channel 22 calculated based on the cross-sectional area of ​​the discharge channel 22 located on the upstream side and a predetermined length of the discharge channel 22 is greater than the volume of the discharge channel 22 calculated based on the cross-sectional area of ​​the discharge channel 22 located on the upstream side and a predetermined length of the discharge channel 22. The predetermined length of the discharge channel can be any arbitrarily set length. For example, the total length of each of the first discharge channel 221, the second discharge channel 222, and the third discharge channel 223 may be set to the predetermined length of the discharge channel. Alternatively, the predetermined length of the discharge channel can be any length set within an arbitrary range for each of the discharge channels 221, the second discharge channel 222, and the third discharge channel 223.

[0054] Specifically, the second discharge channel 222 is molded to have a longer flow path length in the refrigerant flow direction compared to the first discharge channel 221. Furthermore, the volume within the second discharge channel 222 is larger than the volume calculated based on the flow path cross-sectional area and flow path length of the first discharge channel 221.

[0055] Furthermore, the third discharge channel 223 is molded to have a longer flow path length in the refrigerant flow direction compared to the second discharge channel 222. The third discharge channel 223 is molded so that the volume calculated based on the flow path cross-sectional area and flow path length is larger than the volume calculated based on the flow path cross-sectional area and flow path length of the second discharge channel 222.

[0056] This allows for a smooth flow of refrigerant from the upstream to the downstream side in the discharge channel 22, enabling the refrigerant to be discharged without accumulating in the discharge channel 22. More specifically, the battery cooler 1 is provided with a plurality of branched channels 30, and the flow rate of refrigerant flowing into the discharge channel 22 increases as it moves from the upstream side to the downstream side. However, by configuring the discharge channel 22 as described above, the volume of the discharge channel 22 increases as it moves from the upstream side to the downstream side, thus preventing the refrigerant from accumulating in the discharge channel 22.

[0057] Furthermore, instead of comparing the volumes calculated based on the cross-sectional area and length of the discharge channel 22 as in the above configuration, it is also acceptable to compare only the cross-sectional areas of the first discharge channel 221, the second discharge channel 222, and the third discharge channel 223. In other words, it is sufficient that the discharge channel 22 is formed such that the cross-sectional area of ​​the second discharge channel 222 is larger than that of the first discharge channel 221.

[0058] Furthermore, the discharge channel 22 should be formed such that the cross-sectional area of ​​the third discharge channel 223 is larger than that of the second discharge channel 222. Alternatively, the discharge channel 22 may be formed such that its cross-sectional area gradually increases from the upstream side to the downstream side.

[0059] More specifically, in this embodiment, the discharge channels 22 may be formed such that the flow channel cross-sectional area of ​​the discharge channels 22 located downstream is larger than that of the discharge channels 22 located upstream in the refrigerant flow direction. Specifically, the flow channel cross-sectional area of ​​the discharge channels 22 in the portion of the discharge channels 22 where the flow rate of refrigerant flowing in from the second feed channel 33 of the branch channel 30 is large may be formed such that the flow channel cross-sectional area of ​​the discharge channels 22 is larger downstream than that of the upstream side.

[0060] The portion where the flow rate of refrigerant flowing in from the second feed channel 33 increases is, for example, the portion shown by lines D-D, E-E, F-F, and G-G in Figure 8. The cross-sectional area of ​​the flow channel in this portion will now be explained with reference to Figure 9. Figure 9 is a partially enlarged cross-sectional view taken along the lines D-D, E-E, F-F, and G-G in Figure 8.

[0061] As shown in Figure 9, the flow path cross-sectional area is larger in the EE section than in the DD section, the flow path cross-sectional area is larger in the FF section than in the EE section, and furthermore, the flow path cross-sectional area is larger in the GG section than in the FF section. In other words, in the refrigerant flow direction, the downstream discharge flow path 22 is shaped to have a larger flow path cross-sectional area than the upstream side.

[0062] For example, consider the case where the cross-sectional area of ​​the flow path is adjusted to match the GG cross-sectional area, which has the largest flow path cross-sectional area among the DD, EE, FF, and GG cross-sectional areas. In this case, in the DD, EE, and FF cross-sectional areas, the refrigerant flow rate from the branched flow path 30 to the discharge flow path 22 is small relative to the flow path cross-sectional area, and the flow velocity of the refrigerant in the discharge flow path 22 decreases.

[0063] On the other hand, consider the case where the cross-sectional area of ​​the flow path is adjusted to match the DD cross-section, which has the smallest flow path cross-sectional area among the DD, EE, FF, and GG cross-sections. In this case, in the EE, FF, and GG cross-sections, the refrigerant flow rate from the branched flow path 30 to the discharge flow path is large relative to the flow path cross-sectional area, and there is a risk that the pressure resistance will increase excessively.

[0064] Therefore, by shaping the discharge channel 22 as described above, it is possible to prevent a decrease in the flow velocity of the refrigerant flowing through the discharge channel 22 and to prevent an excessive increase in pressure resistance. This is particularly effective when, as in the battery cooler 1 shown in this embodiment, multiple branch channels 30 merge with the discharge channel 22, and the flow rate of the refrigerant at the junction of the discharge channel 22 and the branch channels 30 increases from the upstream side to the downstream side.

[0065] (Modifications) The following modifications can be applied to this embodiment as appropriate. Furthermore, the modifications may be combined with each other to the extent that they are not technically contradictory.

[0066] (Modification 1) In the above-described embodiment, the battery cooler 1 is separate from the case in which the battery cells are housed, and it is explained that the battery cooler 1 is used by contacting the back surface of the surface on which the battery cells are placed in the member that holds the battery cells (hereinafter referred to as the holding member) within this case, but it is not limited to this. For example, the holding member that holds the battery cells may be replaced with the first plate-shaped member 10, and the flow path 100 may be formed integrally with the holding member by joining the holding member and the second plate-shaped member 20. The holding member only needs to have a shape that can hold the battery cells, and may be molded to match the shape of the battery cells. For example, it may be box-shaped or flat.

[0067] (Modification 2) In the embodiment described above, the branched flow path 30 is composed of a plurality of parallel flow paths (first feed flow path 31, return flow path 32, and second feed flow path 33), and the temperature of the joint W is efficiently reduced by increasing the flow velocity and flow rate of the refrigerant flowing through the end flow path 321, but the embodiment is not limited to this. For example, a plurality of parallel flow paths is not an essential configuration, and a single flow path comprising a recessed portion 320 and an end flow path 321 may also be used.

[0068] Even with a single flow path, if the present disclosure is applicable, for example, in a battery cooler equipped with a single flow path, if the size (width) of the battery cell in contact with it is larger than the end flow path 321, heat from the battery cell will be transferred to the portion corresponding to the joint W. Therefore, by increasing the flow velocity and flow rate of the refrigerant flowing through the end flow path 321, the temperature of the portion corresponding to the joint W can be efficiently reduced.

[0069] As explained above, when the flow velocity and flow rate of the refrigerant flowing through the end channel 321 increase, the temperature of the portion adjacent to or in contact with the end channel 321 can be efficiently reduced. The portion adjacent to or in contact with the end channel 321 is the portion where the first plate-shaped member 10 and the second plate-shaped member 20 are joined (hereinafter referred to as the joint W) between the multiple parallel channels (first feed channel 31, return channel 32, and second feed channel 33) shown by the dashed frame W in Figure 5. Therefore, for example, even when the battery cells are in contact with the upper surface of the battery cooler 1, specifically the entire upper surface of the housing groove 11, the temperature of the joint W can be efficiently reduced, and the entire surface of the battery cells can be cooled uniformly.

[0070] (Effects) As described above, the following effects can be obtained according to this embodiment.

[0071] A battery cooler 1 according to aspect 1 of the present disclosure comprises a first plate-shaped member 10, a second plate-shaped member 20, and a flow path 100 formed by joining the first plate-shaped member 10 and the second plate-shaped member 20, for circulating a refrigerant, wherein the flow path 100 has a supply flow path 21 for supplying refrigerant, an inlet 310 connected to the supply flow path 21, a branch flow path 30 branched from the supply flow path 21 for circulating the refrigerant supplied through the inlet 310, and a branch flow path 30 connected to the branch flow path 30 The battery cooler 1 includes a discharge channel 22 through which the discharged refrigerant flows, and the extended portion 40 is formed by joining the first plate-shaped member 10 and the second plate-shaped member 20, and the extended portion 40 is provided at a corner C of the battery cooler 1 and extends adjacent to the outside of the bent portion L formed by the downstream end of the supply channel 21 and the inlet 310, along the direction of refrigerant flow in the supply channel 21, and at least a part of the branch channel 30 is arranged to pass through the extended portion 40.

[0072] According to the above configuration, an extended portion 40 is provided at the corner C of the battery cooler 1, extending adjacent to the outside of the bent portion L. In addition, at least a portion of the branched flow path 30 (the second return flow path R2) is arranged to pass through the extended portion 40. By arranging the second return flow path R2 to pass through the extended portion 40 in this way, the cooling efficiency of the corner C and the area where the extended portion 40 is provided can be improved.

[0073] Therefore, even when battery cells are positioned at locations corresponding to corner C, heat exchange at corner C can be performed efficiently, making it possible to realize a battery cooler 1 that can cool battery cells more uniformly than conventional models.

[0074] The battery cooler 1 according to embodiment 2 of the present disclosure is configured such that, in embodiment 1, the branching flow path 30 is composed of a plurality of parallel flow paths (first supply flow path 31, return flow path 32, second supply flow path 33) arranged in parallel, and a connecting flow path (first return flow path R1, second return flow path R2) that connects the ends of the plurality of parallel flow paths, and at least one of the plurality of parallel flow paths is provided with a recessed portion 320 in which the central part of the parallel flow path is recessed from the outside to the inside in a cross-sectional view perpendicular to the direction of refrigerant flow.

[0075] According to the above configuration, at least one of the parallel flow paths is provided with a recessed portion 320 in which the central part of the parallel flow path is recessed from the outside to the inside. As a result, the flow velocity of the refrigerant flowing through the end flow path 321 increases and the flow rate increases within the parallel flow path.

[0076] Furthermore, as the flow velocity and flow rate of the refrigerant in the relevant section increase, the cooling efficiency in the end flow path 321 improves. Therefore, the cooling efficiency of the battery cooler 1 improves.

[0077] In the battery cooler according to embodiment 3 of the present disclosure, in embodiment 2 described above, the recessed portion may be configured such that the cross-sectional area of ​​the flow path at both ends of the parallel flow path is larger than the cross-sectional area of ​​the flow path at the central portion, with the central portion in between.

[0078] According to the above configuration, the recessed portion 320, with the central portion in between, results in a larger flow path cross-sectional area at both ends (end flow paths 321) of the parallel flow path than at the central portion. As a result, similar to embodiment 2 above, within the parallel flow path, the flow velocity of the refrigerant flowing through the portion where the recessed portion 320 is provided decreases, and the flow rate decreases. Conversely, the flow velocity of the refrigerant flowing through the end flow paths 321 increases, and the flow rate increases. Therefore, a battery cooler 1 that can uniformly cool battery cells can be provided.

[0079] In any of the embodiments 1 to 3 described above, the battery cooler 1 according to embodiment 4 of the present disclosure may be configured such that the discharge channel 22 is formed such that, in the direction of refrigerant flow, the volume of the discharge channel 22 calculated based on the cross-sectional area of ​​the discharge channel 22 located on the upstream side and the length of the flow path of a predetermined length is greater than the volume of the discharge channel 22 calculated based on the cross-sectional area of ​​the discharge channel 22 located on the upstream side and the length of the flow path of a predetermined length.

[0080] For example, in a battery cooler 1, where multiple branched flow channels 30 are provided, the flow rate of refrigerant flowing into the discharge channel 22 increases as you move from the upstream side to the downstream side. However, with the above configuration, the discharge channel 22 is shaped such that, in the direction of refrigerant flow, the volume of the discharge channel 22 located downstream is larger than that of the discharge channel 22 located upstream.

[0081] As a result, the volume of the discharge channel 22 increases as you move from the upstream side to the downstream side. Therefore, even if the flow rate of refrigerant flowing into the discharge channel 22 increases, it is possible to prevent stagnation of refrigerant in the discharge channel 22 and to discharge the refrigerant to the outside of the battery cooler 1 without any problems.

[0082] In any of the embodiments 1 to 4 described above, the battery cooler 1 according to embodiment 5 of the present disclosure may be configured such that, in the direction of refrigerant flow, the discharge channel located downstream has a larger cross-sectional area than the discharge channel located upstream.

[0083] According to the above configuration, in the direction of refrigerant flow, the flow path cross-sectional area of ​​the discharge channel 22 located downstream is larger than that of the discharge channel 22 located upstream. This prevents a decrease in the flow velocity of the refrigerant flowing through the discharge channel 22 and prevents an excessive increase in pressure resistance.

[0084] This disclosure is not limited to the embodiments described above, and various modifications are possible within the scope of the claims. Embodiments obtained by appropriately combining the technical means disclosed in different embodiments are also included in the technical scope of this disclosure.

[0085] 1 Battery cooler 10 First plate-shaped member 20 Second plate-shaped member 21 Supply channel 22 Discharge channel 30 Branch channel 100 Channel 40 Extended section 310 Inlet 320 Recessed section 321 End channel (both ends) L Bent section

Claims

1. A battery cooler comprising a first plate-shaped member, a second plate-shaped member, and a flow path formed by joining the first plate-shaped member and the second plate-shaped member, for circulating a refrigerant, wherein the flow path includes: a supply flow path for supplying a refrigerant; a branch flow path having an inlet connected to the supply flow path and branching off from the supply flow path and circulating the refrigerant supplied through the inlet; and a discharge flow path connected to the branch flow path and circulating the refrigerant to be discharged, wherein an extended portion formed by joining the first plate-shaped member and the second plate-shaped member is provided at a corner of the battery cooler, extending adjacent to the outside of a bend formed by the downstream end of the supply flow path and the inlet, along the direction of refrigerant flow in the supply flow path, and at least a portion of the branch flow path is arranged to pass through the extended portion.

2. The battery cooler according to claim 1, characterized in that the branching channel is composed of a plurality of parallel channels arranged in parallel, and a connecting channel connecting the ends of the plurality of parallel channels, and at least one of the plurality of parallel channels has a recessed portion in which the central part of the parallel channel is recessed from the outside to the inside in a cross-sectional view perpendicular to the direction of refrigerant flow.

3. The battery cooler according to claim 2, characterized in that the recessed portion has a larger cross-sectional area of ​​the flow path at both ends of the parallel flow path, with the central portion in between, than the cross-sectional area of ​​the flow path at the central portion.

4. The battery cooler according to any one of claims 1 to 3, characterized in that the discharge channel is formed such that, in the direction of refrigerant flow, the volume of the discharge channel calculated based on the cross-sectional area of ​​the discharge channel located on the upstream side and the length of the flow channel of a predetermined length is greater than the volume of the discharge channel calculated based on the cross-sectional area of ​​the discharge channel located on the downstream side and the length of the flow channel of a predetermined length.

5. The battery cooler according to any one of claims 1 to 3, characterized in that, in the direction of refrigerant flow, the discharge channel located downstream has a larger cross-sectional area than the discharge channel located upstream.

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