Energy storage device

Abstract

The present invention provides an energy storage device capable of cooling multiple energy storage cells, which can suppress temperature variations among the energy storage cells. [Solution] The energy storage device comprises a plurality of energy storage cells 29A, 29B, and a first heat exchanger 32A and a second heat exchanger 32B that extend in the direction of extension and cool the plurality of energy storage cells 29A, 29B. The first heat exchanger 32A has a first heat medium passage 53A that extends in the direction of extension and through which a heat medium flows, and a first recess 71A formed to narrow the flow area of ​​the first heat medium passage 53A. The second heat exchanger 32B has a second heat medium passage 53B that extends in the direction of extension and through which a heat medium flows, and a second recess 71B formed to narrow the flow area of ​​the second heat medium passage 53B. The depth of the first recess 71A and the depth of the second recess 71B are different.

Description

Technical Field

[0001] The present disclosure relates to a power storage device.

Background Art

[0002] Conventionally, various power storage devices have been proposed. For example, the battery cooling system described in Japanese Unexamined Patent Application Publication No. 2023-162547 includes a first cooling circuit having a first cooling unit that cools a first battery with cooling water, and a second cooling circuit that is provided branching from the first cooling circuit and has a second cooling unit that cools a second battery with cooling water.

[0003] Further, the battery cooling system is provided in the second cooling circuit and includes a pressure loss adjustment unit that adjusts the pressure loss. The pressure loss adjustment unit increases the pressure loss of the cooling water flowing through the second cooling circuit as compared with the case where the pressure loss adjustment unit is not provided in the second cooling circuit. And, a stepped pipe is adopted as the pressure adjustment unit.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] In the above battery cooling system, a stepped pipe is adopted as the pressure loss adjustment unit. Here, if a stepped pipe is adopted as the pressure adjustment unit in both the first cooling circuit and the second cooling circuit, it is necessary to prepare pipes of various sizes. Generally, it is difficult to install many pipes with different diameters, and generally, a pressure loss adjustment unit is formed with pipes having different diameters that can be prepared. As a result, a difference occurs between the flow rate of the refrigerant flowing through the first cooling circuit and the flow rate of the refrigerant flowing through the second cooling circuit, and temperature variations are likely to occur in the first battery and the second battery.

[0006] This disclosure has been made in view of the above-mentioned problems, and its purpose is to provide an energy storage device that can cool multiple energy storage cells and can suppress variations in the temperature of each energy storage cell. [Means for solving the problem]

[0007] The energy storage device comprises a plurality of energy storage cells and a first heat exchanger and a second heat exchanger that extend in the direction of extension and cool the plurality of energy storage cells. The first heat exchanger has a first heat medium passage that extends in the direction of extension and through which a heat medium flows, and a first recess formed to narrow the flow area of ​​the first heat medium passage. The second heat exchanger has a second heat medium passage that extends in the direction of extension and through which a heat medium flows, and a second recess formed to narrow the flow area of ​​the second heat medium passage. The depth of the first recess and the depth of the second recess are different. [Effects of the Invention]

[0008] According to the energy storage device described herein, in an energy storage device that can cool multiple energy storage cells, it is possible to suppress variations in the temperature of each energy storage cell. [Brief explanation of the drawing]

[0009] [Figure 1] This diagram schematically shows a vehicle 1 equipped with an energy storage device 2. [Figure 2] This is an exploded perspective view showing the energy storage device 2. [Figure 3] This is a perspective view showing the energy storage cell 29. [Figure 4] This is a plan view showing the cooling device 12, etc. [Figure 5] This is a perspective view showing the cooling device 12. [Figure 6] This is a plan view showing heat exchangers 32A, 32B, and 32C, and energy storage cells 29A, 29B, 29C, and 29D. [Figure 7]This is an exploded perspective view showing heat exchangers 32A and 32C, and energy storage cells 29A, 29B, 29C, and 29D. [Figure 8] This is a front view showing a portion of the heat exchanger 32A. [Figure 9] This is a front view showing the heat exchanger 32A. [Figure 10] This is a plan view showing the configuration of each recess 71A, 71B, 71C and its surrounding area. [Figure 11] This is a front view of the heat exchanger 32A provided in the energy storage device of Modification 1. [Figure 12] This is a plan view showing a part of the cooling device 12 provided in the energy storage device of Modification Example 2. [Modes for carrying out the invention]

[0010] Embodiments of the present disclosure will be described with reference to Figures 1 to 12. In the drawings referred to below, the same or equivalent components are given the same numbers.

[0011] Figure 1 is a schematic diagram showing a vehicle 1 equipped with an energy storage device 2. The vehicle 1 includes the vehicle body 3, and the energy storage device 2 is mounted on the bottom of the vehicle body 3.

[0012] Figure 2 is an exploded perspective view showing the energy storage device 2. In Figure 2, the width direction W is the width direction of the energy storage device 2, and is also the vehicle width direction of the vehicle 1. The longitudinal direction L is the longitudinal direction of the energy storage device 2, and is also the longitudinal direction of the vehicle 1. The vertical direction H is the vertical direction in the vertical direction.

[0013] The energy storage device 2 includes a housing case 10, an energy storage module 11, a cooling device 12, and electrical equipment 13. The housing case 10 includes a lower case 15, an upper case 16, an insulating plate 17, and a shear panel 18.

[0014] The lower case 15 is formed to open upward, and the upper case 16 is provided to close the opening of the lower case 15.

[0015] The lower case 15 includes a bottom plate 20, a peripheral wall 21, partition walls 22, 23, and an insulating plate 24.

[0016] The bottom plate 20 is formed in a plate shape. The peripheral wall 21 is formed along the outer peripheral edge of the bottom plate 20. The peripheral wall 21 includes a side wall 25, a side wall 26, an end plate 27, and an end plate 28.

[0017] The side walls 25 and the side wall 26 are arranged to be arrayed in the width direction W, and the side walls 25 and the side wall 26 are formed to extend in the front-rear direction L.

[0018] The end plates 27 and the end plate 28 are provided at intervals in the front-rear direction L, and the end plates 27 and the end plate 28 are formed to extend in the width direction W. The end plate 27 connects one end of the side wall 25 and one end of the side wall 26, and the end plate 28 connects one end of the side wall 25 and one end of the side wall 26.

[0019] In addition, fixing parts described later are provided on each of the side walls 25, the side wall 26, the end plate 27, and the end plate 28, and each fixing part is fixed to the vehicle body 3.

[0020] The partition walls 22 and the partition wall 23 are arranged within the region surrounded by the bottom plate 20 and the peripheral wall 21. The partition wall 22 is arranged adjacent to the end plate 27, and the partition wall 22 is formed to extend in the width direction W.

[0021] The partition wall 23 is arranged at an interval in the front-rear direction L with respect to the end plate 28. The end plate 28 is also formed to extend in the width direction W.

[0022] Respiratory membranes 19A, 19B are provided on the end plate 28. The respiratory membranes 19A and the respiratory membrane 19B are waterproof breathable membranes. For example, the respiratory membranes 19A, 19B are formed of Gore-Tex or the like.

[0023] The insulating plate 24 is positioned on the upper surface of the bottom plate 20, between the partition walls 22 and 23. The insulating plate 24 has a plurality of openings 24a. The insulating plate 24 is provided with insulating protectors 24b that close these openings 24a.

[0024] The insulating plate 17 is fixed to the lower surface of the bottom plate 20, and multiple openings 17a are also formed in the insulating plate 17.

[0025] Multiple openings 20a are also formed in the base plate 20. The openings 24a, 20a, and 17a are arranged vertically relative to each other.

[0026] The shear panel 18 is positioned below the insulating plate 17, and its outer edge is fixed to the underside of the base plate 20. The shear panel 18 is formed to cover both the insulating plate 17 and the underside of the base plate 20.

[0027] The energy storage module 11 is located on the upper surface of the insulating plate 24. The electrical equipment 13 is located between the partition wall 23 and the end plate 28.

[0028] The energy storage module 11 includes multiple energy storage cells 29. The multiple energy storage cells 29 are arranged with spacing in the front-to-back direction L and with spacing in the width direction W.

[0029] Figure 3 is a perspective view showing a storage cell 29. The storage cell 29 includes a cell case 4 and an electrode body 5 housed within the cell case 4. The cell case 4 includes a bottom plate, and a smoke exhaust valve 6 is formed on the bottom plate of the cell case 4. Each storage cell 29 is arranged such that the smoke exhaust valve 6 is located above the opening 24a of the insulating plate 24 shown in Figure 2.

[0030] Figure 4 is a plan view showing the cooling device 12, etc., and Figure 5 is a perspective view showing the cooling device 12. Note that the energy storage cells 29, etc., are not shown in Figure 5.

[0031] Referring to Figures 4 and 5, the cooling device 12 includes a heat exchange unit 30 and a heat transfer medium tube 31. The heat exchange unit 30 includes a plurality of heat exchangers 32 and a heat exchanger 33.

[0032] Multiple heat exchangers 32 are arranged with a gap between them in the front-to-back direction L. Each heat exchanger 32 is arranged to extend in the width direction W.

[0033] Between adjacent heat exchangers 32 in the front-to-back direction L, multiple energy storage cells 29 are arranged in the width direction W.

[0034] The heat transfer pipe 31 is located inside the housing case 10 and includes a supply pipe 35 and a discharge pipe 36.

[0035] The supply pipe 35 is connected to the inlet 34A, which is inserted into an insertion hole formed in the end plate 27 and is fixed to the end plate 27.

[0036] The supply pipe 35 includes the main supply pipe 37A, the main supply pipe 37B, and the branch pipes 37C, 37D, and 37E.

[0037] The main supply pipe 37A is positioned between the partition wall 22 and the end plate 27, and is positioned to extend in the width direction W. The main supply pipe 37A is formed to extend toward the side wall 25.

[0038] The main supply pipe 37B is connected to the end of the main supply pipe 37A and is formed to extend in the front-rear direction L along the side wall 25.

[0039] Each branch pipe 37C, 37D, and 37E is positioned below the main supply pipe 37B and connected to the main supply pipe 37B. The branch pipes 37C, 37D, and 37E are spaced apart in the front-to-back direction L.

[0040] Furthermore, the connection points between the main supply pipe 37B and each branch pipe 37C, 37D, and 37E are provided with a gap in the front-to-back direction L.

[0041] Multiple heat exchangers 32, spaced apart in the front-to-back direction L, are connected to branch pipe 37C. Similarly, multiple heat exchangers 32, spaced apart in the front-to-back direction L, are also connected to branch pipes 37D and 37E.

[0042] A heat exchanger 33 is connected to the end of the main supply pipe 37B on the end plate 28 side. The heat exchanger 33 is located on the upper surface of the bottom plate 20, in the portion between the partition wall 23 and the end plate 28. An insulating plate is placed between the heat exchanger 33 and the bottom plate 20. Electrical equipment 13 is placed on the upper surface of the heat exchanger 33. The electrical equipment 13 includes, for example, a battery ECU and a junction box.

[0043] The discharge pipe 36 includes a main discharge pipe 38A, a main discharge pipe 38B, and branch pipes 38C, 38D, and 38E.

[0044] The discharge pipe 36 is connected to the outlet section 34B, which is inserted into an insertion hole formed in the end plate 27 and fixed to the end plate 27. The insertion holes 39A and 39B are formed with a gap in the width direction W.

[0045] The main discharge pipe 38A is positioned between the partition wall 22 and the end plate 27, is positioned to extend in the width direction W, and is formed to extend toward the side wall 26.

[0046] The main discharge pipe 38B is connected to the end of the main discharge pipe 38B and is formed to extend along the side wall 26.

[0047] Each branch pipe 38C, 38D, and 38E is positioned below the main supply pipe 38B and connected to the main supply pipe 37B. The branch pipes 38C, 38D, and 38E are spaced apart in the front-to-back direction L.

[0048] Multiple heat exchangers 32 are connected to branch pipe 38C, spaced apart in the front-to-back direction L. Similarly, multiple heat exchangers 32 are also connected to branch pipes 38D and 38E, spaced apart in the front-to-back direction L. A heat exchanger 33 is connected to the end of the main supply pipe 38B on the end plate 28 side.

[0049] Figure 6 is a plan view showing heat exchangers 32A, 32B, and 32C, and energy storage cells 29A, 29B, 29C, and 29D. Figure 7 is an exploded perspective view showing heat exchangers 32A and 32C, and energy storage cells 29A, 29B, 29C, and 29D.

[0050] The heat exchanger 32A includes a main body 50A, a supply pipe section 51A, and a discharge pipe section 52A. The main body 50A is formed in a plate shape, and the main body 50A is formed to extend in the width direction W.

[0051] The supply pipe section 51A is provided at one end in the width direction W, and the discharge pipe section 52A is provided at the other end.

[0052] The main body 50A is formed in a plate shape and extends in the width direction W. The heat exchanger 32A includes a first main surface 61A, a second main surface 62A, an upper surface 63A, and a lower surface.

[0053] Heat exchangers 32B and 32C are configured similarly to heat exchanger 32A. Energy storage cells 29A and 29B are positioned between heat exchangers 32A and 32B, spaced apart in the width direction W.

[0054] Energy storage cell 29A is located furthest towards branch pipe 37C among multiple energy storage cells arranged between heat exchangers 32A and 32B.

[0055] Energy storage cells 29C and 29D are positioned between heat exchangers 32B and 32C, and are spaced apart in the width direction W.

[0056] Energy storage cell 29C is located furthest towards the branch pipe 37C among the multiple energy storage cells arranged in heat exchanger 32B and heat exchanger 32C.

[0057] Energy storage cells 29A and 29C face each other with a heat exchanger 32B in between, and energy storage cells 29B and 29D face each other with a heat exchanger 32B in between.

[0058] In Figure 7, the branch pipe 37C includes a supply pipe section 51A, a supply pipe section 51B, a supply pipe section 51C, and connecting pipes 55A and 55B.

[0059] The connecting pipe 55A connects the supply pipe section 51A and the supply pipe section 51B, and the connecting pipe 55B connects the supply pipe section 51B and the supply pipe section 51C. The heat transfer medium C flowing through the branch pipe 37C then enters the multiple heat exchangers 32A, 32B, and 32C.

[0060] Figure 8 is a front view showing a portion of the heat exchanger 32A. A heat transfer medium passage 53A is formed inside the main body 50A. The heat transfer medium passage 53A includes a plurality of narrow passages 54A arranged in the vertical direction H.

[0061] A heat transfer medium passage is formed within the supply pipe section 51A through which the heat transfer medium C flows, and this heat transfer medium passage of the supply pipe section 51A is in communication with the heat transfer medium passage 53A of the main body 50A.

[0062] Heat exchanger 32B is configured similarly to heat exchanger 32A, and heat exchanger 32B includes a supply pipe section 51B provided on one end in the width direction W. Furthermore, a refrigerant passage is formed within the body of heat exchanger 32B, and the refrigerant passage of heat exchanger 32B also includes a number of narrow passages arranged in the vertical direction. Heat exchanger 32C is also configured similarly to heat exchanger 32A and heat exchanger 32B.

[0063] Figure 9 is a front view showing the heat exchanger 32A. The heat exchanger 32A has a first recess 71A and a third recess 72A. The first recess 71A is formed in the main body 50A at a position adjacent to the supply pipe section 51A. The third recess 72A is formed at a position further away from the discharge pipe section 52A than the first recess 71A.

[0064] The second main surface 62A includes an arrangement region R0 in which multiple energy storage cells are arranged. The arrangement region R0 includes a contact region R1 in which energy storage cell 29A makes contact, and a contact region R2 in which energy storage cell 29B makes contact.

[0065] In the flow direction DC of the heat transfer medium C within the heat exchanger 32A, the first recess 71A is formed upstream of the contact region R1.

[0066] In the flow direction DC of the heat transfer medium C within the heat exchanger 32A, the third recess 72A is formed in the portion located between the contact region R1 and the contact region R2.

[0067] Similar to heat exchanger 32A, the second recess 71B and the fourth recess 72B are formed in heat exchanger 32B. Similar to heat exchanger 32A, the fifth recess 71C and the sixth recess 72C are formed in heat exchanger 32C. Similar to heat exchanger 32A, the second recess 71B and the fourth recess 72B are formed in heat exchanger 32B. Similar to heat exchanger 32A, the fifth recess 71C and the sixth recess 72C are formed in heat exchanger 32C.

[0068] Figure 10 is a plan view showing the configuration of each recess 71A, 71B, 71C and its surrounding area. The first recess 71A, the second recess 71B, and the fifth recess 71C are arranged in the front-to-back direction L. The third recess 72A, the fourth recess 72B, and the sixth recess 72C are also arranged in the front-to-back direction L.

[0069] The first recess 71A includes a recess A11 formed on the first main surface 61A and a recess A12 formed on the second main surface 62A.

[0070] The third recess 72A includes a recess A21 formed on the first main surface 61A and a recess A22 formed on the second main surface 62A.

[0071] The depth of recesses A11 and A12 is D1A, and the depth of the first recess 71A is the sum of the depths of recesses A11 and A12 (total depth TDA1).

[0072] The depth of recesses A21 and A22 is D2A, and the depth of the third recess 72A is the sum of the depths of recesses A21 and A22 (total depth TDA2).

[0073] The second recess 71B includes a recess B11 formed on the third main surface 61B and a recess B21 formed on the fourth main surface 62B.

[0074] The fourth recess 72B includes a recess B21 formed on the third main surface 61B and a recess B22 formed on the fourth main surface 62B.

[0075] The depth of recesses B11 and B12 is D1B, and the depth of the second recess 71B is the sum of the depths of recesses B11 and B12 (total depth TDB1).

[0076] The depth of recesses B21 and B22 is D2B, and the depth of the fourth recess 72B is the sum of the depths of recesses B21 and B22 (total depth TDB2).

[0077] The first recess 71C includes a recess C11 formed on the fifth main surface 61C and a recess C12 formed on the sixth main surface 62C.

[0078] The sixth recess 72C includes a recess C21 formed on the fifth main surface 61C and a recess C22 formed on the sixth main surface 62C.

[0079] The depth of recesses C11 and C12 is D1C, and the depth of the first recess 71C is the sum of the depths of recesses C11 and C12 (total depth TDC1).

[0080] The depth of recesses C21 and C22 is D2C, and the depth of the sixth recess 72C is the sum of the depths of recesses C21 and C22 (total depth TDC2).

[0081] Here, heat exchanger 32A is located upstream of heat exchanger 32B in the flow direction DC, and the total depth TDA1 is deeper than the total depth TDB1. Also, the total depth TDA2 is deeper than the total depth TDB2. Furthermore, depth D1A is deeper than depth D1B, and depth D2A is deeper than depth D2B.

[0082] Similarly, heat exchanger 32B is located upstream of heat exchanger 32C in the flow direction DC, and the total depth TDB1 is deeper than the total depth TDC1. Also, the total depth TDB2 is deeper than the total depth TDC2. Furthermore, depth D1B is deeper than depth D1C, and depth D2B is deeper than depth D2C.

[0083] The first recess 71A is formed to narrow the flow area of ​​the multiple narrow passages 54A. The third recess 72A is formed in the same way as the first recess 71A, and is also formed to narrow the flow area of ​​the multiple narrow passages 54A. Specifically, it is formed to narrow the flow area of ​​all the narrow passages 54 arranged in the vertical direction H.

[0084] Here, the first recess 71A and the third recess 72A can be easily formed, for example, by pressing a pressure roller against the first main surface 61A and the second main surface 62A of the heat exchanger 32A from the outside. Furthermore, the depth of the first recess 71A and the third recess 72A can be adjusted by adjusting the pressure applied by the pressure rotor against the first main surface 61A and the second main surface 62A.

[0085] Furthermore, the second recess 71B and the fourth recess 72B formed within the heat exchanger 32B are also formed to narrow the flow area of ​​the narrow passage 54B of the refrigerant passage 53B formed within the heat exchanger 32B. Similarly, the fifth recess 71C and the sixth recess 72C formed within the heat exchanger 32C are also formed to narrow the flow area of ​​the narrow passage 54C of the refrigerant passage 53C formed within the heat exchanger 32C.

[0086] Furthermore, the flow area of ​​the refrigerant passage 53A in the portion where the first recess 71A and the third recess 72A are located is smaller than the flow area of ​​the refrigerant passage 53B in the portion where the second recess 71B and the fourth recess 72B are located. Similarly, the flow area of ​​the refrigerant passage 53B in the portion where the second recess 71B and the fourth recess 72B are located is smaller than the flow area of ​​the refrigerant passage 53C in the portion where the fifth recess 71C and the sixth recess 72C are located.

[0087] In Figure 10, an elastic member 80 is placed between the energy storage cells 29A and 29B and the heat exchangers 32A and 32B. Similarly, an elastic member 80 is also placed between the energy storage cells 29C and 29D and the heat exchangers 32A and 32B. The elastic member 80 is an insulating material. The elastic member 80 may also have heat insulating properties. The elastic member 80 is not an essential component, and it may be omitted.

[0088] In the energy storage device 2 configured as described above, when the cooling device 12 shown in Figure 4 is activated, the heat transfer medium C enters the heat transfer pipe 31 from the inlet 34A, and the heat transfer medium C flows through the heat transfer pipe 31.

[0089] The heat transfer medium C flows through supply pipe section 51A and supply pipe section 51B, and enters the main supply pipes 37A, 37B, and 37C from supply pipe section 51B.

[0090] In Figure 6, the heat transfer medium C that enters the branch pipe 37C enters the heat exchanger 32A. Here, the heat exchanger 32A has first recesses 71A and third recesses 72A formed sequentially in the flow direction DC within the heat exchanger 32A. This allows for adjustment of pressure loss at each position in the heat exchanger 32A. Furthermore, by forming multiple recesses, the flow velocity of the heat transfer medium C flowing through the heat exchanger 32A can be equalized. Consequently, a temperature difference can be created in each energy storage cell. When a heat transfer medium C at a lower temperature flows through the heat exchanger 32A, or when a heat transfer medium C at a higher temperature flows through the heat exchanger 32A, the heat exchanger 32A expands and contracts. At this time, the heat exchanger 32A has multiple first recesses 71A and third recesses 72A formed in the direction in which the heat exchanger 32A extends, allowing the heat exchanger 32A to expand and contract in the direction in which the heat exchanger 32A extends. This suppresses damage to the heat exchanger 32A due to thermal stress. Similar effects can be obtained in other heat exchangers as well.

[0091] When the heat exchanger 32A cools each energy storage cell 29, the temperature of the heat transfer medium C is low. Furthermore, the temperature of the heat transfer medium C passing through the first recess 71A is lower than the temperature of the heat transfer medium C passing through the third recess 72A, so the flow resistance of the heat transfer medium C in the first recess 71A is high. On the other hand, in the third recess 72A, it is easily heated by the heat from each energy storage cell 29, so the flow resistance of the heat transfer medium C is low.

[0092] Furthermore, when the temperature of the heat transfer medium C is high, the flow resistance in the first recess 71A becomes relatively low, and the flow resistance in the third recess 72A becomes relatively high.

[0093] In this way, since the first recess 71A and the third recess 72A formed in the heat exchanger 32A are spaced apart in the width direction W, even if the temperature of the heat transfer medium C changes, it is possible to suppress large fluctuations in the flow resistance of the heat exchanger 32A formed by the first recess 71A and the third recess 72A.

[0094] The heat transfer medium C that enters the branch pipe 37C then sequentially enters the heat exchangers 32A, 32B, and 32C.

[0095] Heat exchanger 32A is located upstream of heat exchanger 32B in the flow direction DC of the branch pipe 37C, and the flow resistance of the heat transfer medium C from the inlet 34A to heat exchanger 32A is smaller than the flow resistance from the inlet 34A to heat exchanger 32B.

[0096] In Figure 10, the total depth TDA1 of the first recess 71A is deeper than the total depth TDB1 of the second recess 71B, and the total depth TDA2 of the second recess 71B is deeper than the total depth TDB2 of the first recess 71C. As a result, the flow resistance of the heat transfer medium C in the heat exchanger 32A is higher than the flow resistance in the heat exchanger 32B.

[0097] As a result, it is possible to suppress the difference between the flow rate of the heat transfer medium C flowing through the heat exchanger 32A and the flow rate of the heat transfer medium C flowing through the heat exchanger 32B.

[0098] Similarly, it is possible to suppress the difference between the flow rate of the heat transfer medium C flowing through the heat exchanger 32C and the flow rate of the heat transfer medium C flowing through the heat exchanger 32D.

[0099] The energy storage cells 29A to 29D deform by expanding and contracting during charging and discharging. On the other hand, the first recess 71A is located upstream of the arrangement region R0 in the flow direction DC. Therefore, even if the energy storage cells 29A to 29D deform due to charging and discharging, deformation of the first recess 71A is suppressed.

[0100] Furthermore, the third recess 72A is positioned between the contact area R1 and the contact area R2, and deformation of the second recess 71B is suppressed even if each energy storage cell deforms due to charging and discharging.

[0101] In this way, since the deformation of each first recess 71A and third recess 72A is suppressed, fluctuations in the flow resistance of the heat transfer medium C to the heat exchanger 32A can be suppressed.

[0102] Of the multiple energy storage cells 29 positioned between heat exchangers 32A and 32B, the energy storage cell 29 located in the center in the width direction W tends to have a higher temperature.

[0103] Therefore, the energy storage cells 29 located in the placement area R0 are prone to thermal expansion. On the other hand, since the second recess 71B is located away from the placement area R0, deformation of the second recess 71B is suppressed.

[0104] The first recess 71A includes a recess A11 formed on the first main surface 61A and a recess A12 formed on the second main surface 62A. Therefore, it is possible to suppress the occurrence of a difference in rigidity between the first main surface 61A side and the second main surface 62A side in the energy storage cell 29A.

[0105] Similarly, the third recess 72A includes a recess A21 formed on the first main surface 61A and a recess A12 formed on the second main surface 62A, thereby suppressing a difference in rigidity between the first main surface 61A and the second main surface 62A.

[0106] The first recess 71A and the third recess 72A are formed to narrow the flow area of ​​all heat transfer tubes 31 arranged in the vertical direction H, thereby suppressing variations in the cooling performance of the heat exchanger 32A in the vertical direction H. In the above embodiment, the depth of the first recess 71A and the depth of the third recess 72A may be different. For example, the depth of the third recess 72A may be made shallower than that of the first recess 71A. Since the energy storage cell 29B is located closer to the center of the energy storage device than the energy storage cell 29A, the temperature of the energy storage cell 29B tends to be higher than that of the energy storage cell 29A. As a result, the energy storage cell 29B is more prone to expansion than the energy storage cell 29A, and the narrow passage 54A near the energy storage cell 29B tends to be narrowed. On the other hand, by making the depth of the third recess 72A shallower, it is possible to suppress the flow resistance of the heat exchanger 32A near the energy storage cell 29B from becoming too high. (Variation 1) The energy storage device according to Modification 1 will be explained using Figure 11. Figure 11 is a front view of the heat exchanger 32A provided in the energy storage device according to Modification 1. In the example shown in Figure 11, the first recess 71A formed in the heat exchanger 32A is formed in a dashed line shape in the vertical direction H. Thus, various shapes can be adopted for the first recess 71A.

[0107] For example, the first recess 71A may be formed on the upper and lower ends of the heat exchanger 32A in the vertical direction H. The temperature of each energy storage cell 29 tends to be higher in the center of the vertical direction H. Therefore, by ensuring the flow rate of the heat transfer medium C in the center of the vertical direction H, it is possible to suppress temperature variations in each energy storage cell 29 in the vertical direction H. Not only the first recess 71A, but other recesses 72A, 71B, 72B, etc. may be formed in a dashed line shape.

[0108] (Modification 2) The energy storage device according to Modified Example 2 will be explained using Figure 12. Figure 12 is a plan view showing a part of the cooling device 12 provided in the energy storage device of Modified Example 2. In this cooling device 12, in the flow direction DC within the heat exchanger 32A, the first recess 71A is formed between the energy storage cells 29A and 29B. The second recess 71B is formed in the flow direction DC within the heat exchanger 32B between the energy storage cells 29A and 29B. The fifth recess 71C is also formed in the flow direction DC within the heat exchanger 32C between the energy storage cells 29C and 29D. Even in such a cooling device 12, it is possible to equalize the flow rate of the heat transfer medium C flowing through each of the heat exchangers 32A, 32B, and 32B.

[0109] The embodiments disclosed herein should be considered in all respects to be illustrative and not restrictive. The scope of this disclosure is indicated by the claims rather than by the description of the embodiments above, and all modifications within the meaning and scope equivalent to the claims are intended to be included. [Explanation of Symbols]

[0110] 1 Vehicle, 2 Energy storage device, 3 Vehicle body, 4 Cell case, 5 Electrode body, 6 Smoke exhaust valve, 10 Housing case, 11 Energy storage module, 12 Cooling device, 13 Electrical equipment, 15 Lower case, 16 Upper case, 17 Insulating plate, 17a, 20a, 24a Opening, 18 Shear panel, 19A, 19B Breathing membrane, 20 Bottom plate, 21 Peripheral wall, 22, 23 Partition wall, 24 Insulating plate, 24b Insulating protector, 25, 26 Side wall, 27, 28 End plate, 29, 29A, 29B, 29C, 29D Energy storage cell, 30 Heat exchange unit, 31 Heat transfer tube, 32, 32A, 32B, 32C, 33 Heat exchanger, 34A Inlet, 34B Outlet, 35 Supply pipe, 36 Discharge pipe, 37A, 37B Main supply pipe, 37C, 37D, 37E, 38C, 38D, 38E Branch pipe, 38A, 38B Main discharge pipe, 39A, 39B Insertion hole, 50A Main body, 51A, 51B, 51C Supply pipe section, 52A Discharge pipe section, 53A Heat medium passage, 54 Narrow passage, 55A, 55B Connecting pipe, 61A first main surface, 61B third main surface, 61C fifth main surface, 62A second main surface, 62B fourth main surface, 62C sixth main surface, 71A, 72A first recess, 71B, 72B second recess, 71C, 72C third recess.

Claims

1. Multiple energy storage cells, The plurality of energy storage cells are cooled by a first heat exchanger and a second heat exchanger that extend in the direction of extension, Equipped with, The first heat exchanger includes: A first heat transfer medium passage extends in the aforementioned extending direction and through which the heat transfer medium flows inside the first heat exchanger, A first recess is formed to narrow the flow area of ​​the first heat transfer medium passage, The second heat exchanger includes: A second heat transfer medium passage extends in the aforementioned extending direction and through which the heat transfer medium flows inside the second heat exchanger, A second recess is formed to narrow the flow area of ​​the second heat transfer medium passage, An energy storage device in which the depth of the first recess and the depth of the second recess are different.

2. The first heat exchanger and the second heat exchanger are arranged with an interval between them in the direction of arrangement. The plurality of energy storage cells include a first energy storage cell and a second energy storage cell arranged between the first heat exchanger and the second heat exchanger, In the flow direction of the heat transfer medium, the second energy storage cell is positioned downstream of the first energy storage cell at a distance from it. In the flow direction of the heat transfer medium, the first recess is formed upstream of the first energy storage cell. The energy storage device according to claim 1, wherein the second recess is formed upstream of the first energy storage cell in the flow direction of the heat transfer medium.

3. The first heat exchanger and the second heat exchanger are arranged with an interval between them in the direction of arrangement. The plurality of energy storage cells include a first energy storage cell and a second energy storage cell arranged between the first heat exchanger and the second heat exchanger, In the flow direction of the heat transfer medium, the first recess is formed between the first energy storage cell and the second energy storage cell. The energy storage device according to claim 1, wherein the second recess is formed between the first energy storage cell and the second energy storage cell in the flow direction of the heat transfer medium.

4. In the flow direction of the heat transfer medium, the first heat exchanger has a third recess located downstream of the first recess. In the flow direction of the heat transfer medium, the second heat exchanger has a fourth recess formed downstream of the second recess. The plurality of energy storage cells include a first energy storage cell and a second energy storage cell arranged between the first heat exchanger and the second heat exchanger, In the flow direction of the heat transfer medium, the second energy storage cell is positioned downstream of the first energy storage cell at a distance from it. In the flow direction of the heat transfer medium, the first recess is formed upstream of the first energy storage cell, and the third recess is formed between the first energy storage cell and the second energy storage cell. The energy storage device according to claim 1, wherein, in the flow direction of the heat transfer medium, the second recess is formed upstream of the first energy storage cell, and the fourth recess is formed between the first energy storage cell and the second energy storage cell.

5. The first heat exchanger and the second heat exchanger are further provided with supply pipes for supplying the heat transfer medium to the heat transfer medium, In the flow direction of the heat transfer medium flowing through the supply pipe, the first heat exchanger is positioned upstream of the second heat exchanger. The energy storage device according to any one of claims 1 to 4, wherein the depth of the first recess is greater than the depth of the second recess.

6. The first heat exchanger and the second heat exchanger are further provided with supply pipes for supplying the heat transfer medium to the heat transfer medium, In the flow direction of the heat transfer medium flowing through the supply pipe, the first heat exchanger is positioned upstream of the second heat exchanger. The depth of the first recess is greater than the depth of the second recess. The energy storage device according to claim 4, wherein the depth of the third recess is greater than the depth of the fourth recess.

7. The first heat exchanger has a first flow passage through which the heat transfer medium flows. The first flow passage includes a plurality of first narrow passages arranged in the height direction, The second heat exchanger has a second flow passage through which the heat transfer medium flows. The second flow passage includes a plurality of second narrow passages arranged in the vertical direction, The first recess is formed to narrow at least one of the plurality of first channels, The energy storage device according to claim 1, wherein the second recess is formed to narrow at least one of the plurality of second flow channels.

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