Battery module

Abstract

To provide a battery module in which a fluid can be easily and evenly flown into plural battery cells.SOLUTION: A battery module 10 includes: a plurality of columnar battery cells 20; a storage unit 30 for storing the battery cells 20 into a storage space 31A while the directions of the axes of the battery cells 20 are being in parallel to one another, the storage unit receiving flow of a fluid into the inside; and a supply unit 34 for supplying the fluid into a storage space 31A. The storage unit 30 has a chamber 36 leading to the supply path 34 and the storage space 31A. The chamber 36 lowers the flow rate of the fluid supplied from the supply path 34 and supplies the fluid into the storage space 31A.SELECTED DRAWING: Figure 6

Description

Technical Field

[0001] The present invention relates to a battery module.

Background Art

[0002] The temperature control device for battery cells disclosed in Patent Document 1 includes a rectangular parallelepiped hollow body that houses a plurality of cylindrical battery cells. A temperature-controlled fluid is supplied inside the hollow body. The fluid that has circulated inside the hollow body is discharged from inside the hollow body.

[0003] The temperature control device for battery cells disclosed in Patent Document 2 is a device that adjusts the temperature of a plurality of battery cells housed in a base. The base includes two opposing seal elements. The seal elements surround the periphery of the battery cells. The seal elements have opposing passage openings that are paired with respect to one coupling axis. A flow path extending in a lateral direction with respect to the coupling axis is provided in the base.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0005] In the devices of Patent Documents 1 and 2, in the housing member that houses a plurality of battery cells, the positions of the respective battery cells are different with respect to the location where the fluid enters. Therefore, it is assumed that for some battery cells, it is difficult for the fluid to flow in. Thus, a configuration in which the fluid can easily flow in evenly for each battery cell is required.

[0006] The present invention has been completed based on the above circumstances, and an object thereof is to provide a battery module in which a fluid can easily flow evenly into a plurality of battery cells.

Means for Solving the Problems

[0007] The battery module of the present invention is a battery module that performs temperature adjustment using a fluid, a plurality of columnar battery cells, a housing portion that houses the plurality of battery cells in a state where the axial directions of the plurality of battery cells are parallel, and the fluid is supplied to the inside, a supply path that supplies the fluid to the housing space, and is provided with the housing portion has a chamber that communicates with the supply path and the housing space, the chamber supplies the fluid to the housing space by reducing the flow rate of the fluid supplied from the supply path.

Effects of the Invention

[0008] According to this configuration, a battery module in which a fluid can easily flow evenly into a plurality of battery cells can be provided.

Brief Description of the Drawings

[0009]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Modes for Carrying Out the Invention

[0010] The chamber has a plurality of openings leading to the accommodation space, and it is preferable that the plurality of openings supply the fluid to different positions in the accommodation space respectively. With such a configuration, as the fluid flows into the accommodation space from different positions in the accommodation space, it becomes easier to disperse and supply the fluid from the chamber to the accommodation space.

[0011] The opening is preferably slit-shaped. With such a configuration, the fluid can flow from the slit-shaped opening into the accommodation space, and it becomes easier to define the supply direction of the liquid from the chamber to the accommodation space.

[0012] The plurality of battery cells include a first battery cell and a second battery cell arranged side by side in a first direction orthogonal to the axial direction, and a third battery cell arranged at a position separated from the first battery cell and the second battery cell in a second direction orthogonal to the axial direction and the first direction. The chamber is preferably provided between the first battery cell and the second battery cell in the first direction and adjacent to the first battery cell, the second battery cell, and the third battery cell. With such a configuration, since the first battery cell, the second battery cell, and the third battery cell are not arranged side by side in the first direction, the size of the battery module in the first direction can be reduced compared to the configuration in which these three battery cells are arranged side by side in the first direction. Moreover, the chamber can be efficiently provided by utilizing the space between the first battery cell and the second battery cell.

[0013] <Example 1> Hereinafter, Example 1 embodying the present invention will be described with reference to FIGS. 1-6. In the following description, regarding the front-rear direction, the F direction in FIGS. 1-3 is defined as the front. Regarding the up-down direction, the H direction in FIGS. 1-3 is defined as the up. Regarding the left-right direction, the L direction in FIGS. 1 and 2 is defined as the left.

[0014] (Configuration of Battery Module 10) The battery module 10 of the first embodiment is shown in FIG. 1. The battery module 10 performs temperature adjustment using a fluid. For example, when cooling the inside of the battery module 10, cooling water is used as the fluid. The liquid is, for example, an antifreeze. The battery module 10 is mounted on a vehicle. The battery module 10 functions as a power source that supplies power to electronic devices mounted on the vehicle.

[0015] As shown in FIG. 2, the battery module 10 includes a plurality of battery cells 20, a housing portion 30, gaskets 40 and 50, covers 60 and 70, bus bars 80 and 90, bolts 100, and nuts 110.

[0016] (Battery cell 20) The battery cell 20 has a positive electrode and a negative electrode. The battery cell 20 is columnar. The positive electrode is provided at one of the ends (the lower end portion 21 and the upper end portion 22) of the battery cell 20. The negative electrode is provided at the other of the ends (the lower end portion 21 and the upper end portion 22) of the battery cell 20. The battery cell 20 may be subjected to insulation treatment or waterproof treatment. For example, an insulating coating may be applied to a portion of the battery cell 20 that can come into contact with the fluid. Thereby, the battery cell 20 can be in direct contact with the fluid while preventing the fluid from entering the inside.

[0017] (Housing portion 30) The housing portion 30 houses a plurality of battery cells 20. The housing portion 30 is an integral and inseparable single member made of a relatively hard resin material (for example, PP (polypropylene), etc.). The housing portion 30 has a main body portion 31 having a shape along the outer shape of the plurality of battery cells 20. An accommodation space 31A for accommodating the plurality of battery cells 20 is formed in the main body portion 31. The main body portion 31 penetrates in the vertical direction. That is, in the main body portion 31, an opening 31B is provided on the lower side and an opening 31C is provided on the upper side.

[0018] As shown in FIG. 4, the accommodation space 31A includes a plurality of cell spaces 32 for accommodating the battery cells 20. One battery cell 20 is accommodated in one cell space 32. The cell space 32 has a columnar shape with an axis parallel to the vertical direction. The accommodation space 31A accommodates the plurality of battery cells in a state where the axial directions of the plurality of battery cells 20 are parallel. The axial directions of the plurality of battery cells 20 are parallel to the vertical direction. In the main body 31, rows of four cell spaces 32 arranged along the front-rear direction are arranged in three rows in the left-right direction. The plurality of cell spaces 32 are arranged in a staggered pattern along the front-rear direction. The main body 31 has an inner frame portion 33. The inner frame portion 33 partitions a part of the plurality of cell spaces 32 on the central side. The cell space 32 communicates with adjacent cell spaces 32.

[0019] A supply path 34 is formed in the main body 31. The supply path 34 is a flow path for supplying fluid from the outside of the housing portion 30 to the accommodation space 31A. The front end side of the supply path 34 has a pipe shape extending toward the accommodation space 31A.

[0020] At the rear end side of the main body 31, a protruding portion 31D protruding rearward from the center in the left-right direction is formed. A discharge path 35 is formed in the protruding portion 31D. The discharge path 35 is a flow path for discharging fluid from the accommodation space 31A to the outside of the housing portion 30.

[0021] A chamber 36 is provided in the front wall portion of the main body 31. The chamber 36 is formed between the supply path 34 and the accommodation space 31A. The chamber 36 communicates with the supply path 34 and the accommodation space 31A. The chamber 36 reduces the flow rate of the fluid supplied from the supply path 34 and supplies the fluid to the accommodation space 31A. The space inside the chamber 36 has a rectangular parallelepiped shape with rounded corners. An opening 36A opened upward is formed at the upper end of the chamber 36.

[0022] The supply path 34 is connected to a position slightly below the upper end in the chamber 36. The area of a cross-section orthogonal to the front-rear direction of the internal space of the supply path 34 is defined as the cross-sectional area of the internal space of the supply path 34. The area of a cross-section orthogonal to the vertical direction of the internal space of the chamber 36 is defined as the cross-sectional area of the internal space of the chamber 36. The cross-sectional area of the internal space of the chamber 36 is larger than the cross-sectional area of the internal space of the supply path 34. For example, it is preferable that the cross-sectional area of the internal space of the chamber 36 is three times or more larger than the cross-sectional area of the internal space of the supply path 34.

[0023] The chamber 36 has a plurality of openings 36B and 36C that connect to the accommodation space 31A. The plurality of openings 36B and 36C supply fluid to different positions in the accommodation space 31A, respectively. The opening 36B is formed at the rear end and the center in the left-right direction of the chamber 36. The opening 36B is slit-shaped. The opening 36B is formed over the entire vertical direction from the lower end to the upper end of the chamber 36. The opening 36B is connected to the cell space 32C located at the center in the left-right direction and the most front side.

[0024] The openings 36C are respectively formed at both the left and right ends of the chamber 36. The openings 36C are formed at the center in the front-rear direction in the chamber 36. The openings 36C are slit-shaped. The openings 36C are formed over the entire vertical direction from the lower end to the upper end of the chamber 36. Each opening 36C is respectively connected to a pair of cell spaces 32B located at both the left and right ends and the most front side.

[0025] As shown in FIG. 4, the main body portion 31 has a plurality of protruding portions 37 that protrude toward the accommodation space 31A. The protruding portions 37 are formed between adjacent cell spaces 32 in the front-rear direction. The protruding portions 37 are shaped such that the width in the front-rear direction becomes narrower toward the tip. The thickness of the protruding portions 37 in the vertical direction is approximately the same as that of the other portions of the main body portion 31. On the base end side of the protruding portions 37 in the protruding direction, slits 37A and 37B that are recessed toward the center in the vertical direction are formed. The slit 37A is recessed upward from the lower end of the protruding portion 37. The slit 37B is recessed downward from the upper end of the protruding portion 37. The slits 37A and 37B communicate with the adjacent cell spaces 32.

[0026] (Gaskets 40, 50) As shown in FIG. 3, the gasket 40 is attached to the lower opening 31B of the housing portion 30. The gasket 40 is, for example, an integrally inseparable single member made of an elastically deformable resin material. Examples of the resin material include elastomers such as TPE and EPDM. As shown in FIG. 2, the gasket 40 has a plate portion 41 and a plurality of seal portions 42.

[0027] The shape of the outer peripheral edge of the plate portion 41 is the same as the shape of the outer peripheral edge of the lower end of the housing portion 30. The outer peripheral edge of the plate portion 41 overlaps the lower end of the housing portion 30 from below. The plate surface of the plate portion 41 is larger than the opening area of the opening 31B of the housing portion 30.

[0028] The seal portion 42 is in liquid-tight contact with the axial end portion (lower end portion 21) of the battery cell 20. The lower end portion 21 of the battery cell 20 is press-fitted into the cylindrical portion of the seal portion 42. A circular hole 45 is formed at the bottom of the seal portion 42.

[0029] As shown in FIG. 2, the gasket 50 has the same configuration as the gasket 40. That is, the gasket 50 has a plate portion 51 and a plurality of seal portions 52 which have the same configuration as the plate portion 41 and the plurality of seal portions 42 respectively. The front end portion of the plate portion 51 closes the opening 36A of the chamber 36 from above. As shown in FIG. 3, the seal portion 52 is in liquid-tight contact with the axial end portion (upper end portion 22) of the battery cell 20. A hole 55 having the same configuration as the hole 45 is formed at the bottom of the seal portion 52.

[0030] (Cover 60, 70) As shown in FIG. 3, the cover 60 closes the opening 31B. The cover 60 sandwiches the gasket 40 with the housing portion 30. The cover 60 is an integral and inseparable single member made of a relatively hard resin material (for example, PP (polypropylene)). The cover 60 may be made of the same material as the housing portion 30.

[0031] As shown in FIG. 2, the cover 60 has a plate portion 61 that closes the opening 31B. A recess 62 that is recessed downward is formed in the central side portion (portion excluding the outer peripheral edge) of the plate portion 61. The recess 62 has a shape corresponding to the plate portion 51 of the gasket 50. The plate portion 51 of the gasket 50 fits into the recess 62. At the bottom of the recess 62, holes 63 are formed at a plurality of positions corresponding to the plurality of cell spaces 32 of the housing portion 30 (a plurality of positions corresponding to the plurality of holes 45 of the gasket 40).

[0032] As shown in FIG. 2, the cover 70 has the same configuration as the cover 60. That is, the cover 70 has a plate portion 71 having the same configuration as the plate portion 61. A recess 72 (see FIG. 3) having the same configuration as the recess 62 is formed in the plate portion 71. A hole 73 having the same configuration as the hole 63 is formed in the recess 72.

[0033] (Bus bars 80, 90) As shown in FIG. 3, the bus bars 80 and 90 are connected to the positive and negative electrodes (lower end portion 21 and upper end portion 22) of the battery cell 20. As shown in FIG. 2, the bus bar 80 has a main body portion 81 and a tab portion 82. The main body portion 81 is continuous with six tab portions 82. The arrangement of the six tab portions 82 is an arrangement (alternate arrangement) corresponding to the six cell spaces 32 on the front end side of the accommodating portion 30.

[0034] The bus bar 90 is continuous with three tab portions 92. The arrangement of the three tab portions 92 is an arrangement (alternate arrangement) corresponding to the three cell spaces 32 on the front end side of the accommodating portion 30.

[0035] As shown in FIG. 3, two bus bars 80 are assembled to the cover 60. The tab portion 82 is connected to the electrode (lower end portion 21) of the battery cell 20 through the hole 45 of the gasket 40 and the hole 63 of the cover 60.

[0036] As shown in FIG. 3, one bus bar 80 and two bus bars 90 are assembled to the cover 70. The tab portion 82 and the tab portion 92 are connected to the electrode (upper end portion 22) of the battery cell 20 through the hole 55 of the gasket 50 and the hole 73 of the cover 70.

[0037] (Bolt 100 and Nut 110) Four bolts 100 and four nuts 110 are assembled to the accommodating portion 30 and the covers 60 and 70. The shaft of the bolt 100 penetrates through the accommodating portion 30 and the gaskets 40 and 50. The nut 110 is fastened to the shaft of the bolt 100. The accommodating portion 30 and the covers 60 and 70 are clamped by the head of the bolt 100 and the nut 110.

[0038] (Arrangement Structure of Battery Cell 20) As shown in FIG. 6, in a state where a plurality of battery cells 20 are housed in the housing portion 30, the first cell group A, the second cell group B, and the third cell group C are included, in each of which four battery cells 20 are arranged in the front-rear direction. In the housing portion 30, the first cell group A, the second cell group B, and the third cell group C are arranged in this order from the left side to the right side. The first cell group A, the second cell group B, and the third cell group C are arranged in a staggered pattern along the front-rear direction.

[0039] The battery cell 20 located at the most front in the first cell group A is defined as the battery cell A1. The battery cell 20 located at the most front in the second cell group B is defined as the battery cell B1. The battery cell 20 located at the most front in the third cell group C is defined as the battery cell C1. The battery cell A1 corresponds to the "first battery cell" of the present invention. The battery cell B1 corresponds to the "second battery cell" of the present invention. The battery cell C1 corresponds to the "third battery cell" of the present invention. The battery cell A1 and the battery cell B1 are arranged side by side in the left-right direction (the first direction) orthogonal to the up-down direction (the axial direction of the battery cell 20). The battery cell C1 is arranged at a position (rear position) separated from the battery cell B1 and the battery cell C1 in the front-rear direction (the second direction) orthogonal to the up-down direction (the axial direction of the battery cell 20) and the left-right direction (the first direction).

[0040] The chamber 36 is provided between the battery cell A1 and the battery cell B1 in the left-right direction and is adjacent to the battery cells A1, B1, and C1. The battery cell A1 is adjacent to the chamber 36 on the left side. The battery cell B1 is adjacent to the chamber 36 on the right side. The battery cell C1 is adjacent to the chamber 36 on the rear side. The opening 36B faces the outer peripheral surface of the battery cell C1 from the front side. The left opening 36B faces the outer peripheral surface of the battery cell A1 from the right side. The right opening 36B faces the outer peripheral surface of the battery cell B1 from the left side.

[0041] The battery cell 20 located at the most rear in the third cell group C is defined as the battery cell C4. The battery cell C4 faces the front end portion of the discharge path 35 from the front side.

[0042] (Flow of fluid in battery module 10) The flow of fluid in battery module 10 will be described. The fluid supplied from supply passage 34 to chamber 36 is temporarily stored in chamber 36. Since the cross-sectional area of the internal space of chamber 36 is larger than that of the internal space of supply passage 34, the flow velocity of the fluid decreases when the fluid flows from supply passage 34 into chamber 36.

[0043] As shown by the arrows in FIG. 5, the fluid in chamber 36 flows out into accommodation space 31A from openings 36B and 36C. The fluid flowing out from openings 36B and 36C flows backward while hitting the outer peripheral surfaces of each battery cell 20. Specifically, the fluid flows on plate portion 41 of gasket 40 and flows backward while hitting the outer surface of seal portion 42 and the inner surface of accommodation portion 30 in addition to the outer peripheral surfaces of each battery cell 20. The fluid flowing at a relatively high position in accommodation space 31A can pass over the upper surface of inner frame portion 33 shown in FIG. 6.

[0044] The fluid can pass through slits 37A (see FIG. 5) and 37B (see FIG. 6) formed in protrusion 37. Therefore, it becomes easier for the fluid to pass along the left side portions of the outer peripheral surfaces of the battery cells 20 in the first cell group A and the right side portions of the outer peripheral surfaces of the battery cells 20 in the second cell group B.

[0045] As shown in FIGS. 5 and 6, battery module 10 has a symmetric configuration in the left-right direction. Therefore, it becomes equally easy for the fluid supplied from supply passage 34 to flow into the battery cells 20 arranged side by side in the left-right direction between the first cell group A and the second cell group B.

[0046] As shown by the arrow in FIG. 6, the fluid flowing backward in accommodation space 31A is discharged to the outside of battery module 10 through discharge passage 35.

[0047] (Operation of battery module 10) Next, the operation of the battery module 10 of the first embodiment will be described. The battery module 10 of the first embodiment includes a plurality of columnar battery cells 20, a housing portion 30 that houses the plurality of battery cells 20 in a state where the axial directions of the plurality of battery cells 20 are parallel, and a housing space 31A into which a fluid is supplied, and a supply path 34 that supplies the fluid to the housing space 31A. The housing portion 30 has a chamber 36 that communicates with the supply path 34 and the housing space 31A. The chamber 36 reduces the flow velocity of the fluid supplied from the supply path 34 and supplies the fluid to the housing space 31A. With such a configuration, by reducing the flow velocity of the fluid, the liquid is likely to spread (the directionality is likely to be weakened), and the fluid is likely to flow evenly into each battery cell 20 in the housing space 31A.

[0048] In the battery module 10 of the first embodiment, the chamber 36 has a plurality of openings 36B and 36C that lead to the housing space 31A. The plurality of openings 36B and 36C supply the fluid to different positions in the housing space 31A. With such a configuration, by allowing the fluid to flow into the housing space 31A from different positions, it becomes easier to disperse and supply the fluid from the chamber 36 to the housing space 31A.

[0049] In the battery module 10 of the first embodiment, the openings 36B and 36C are slit-shaped. With such a configuration, the fluid can flow from the slit-shaped openings 36B and 36C into the housing space 31A, and it becomes easier to define the supply direction of the liquid from the chamber 36 to the housing space 31A.

[0050] In the battery module 10 of the first embodiment, the plurality of battery cells 20 include a battery cell A1 (first battery cell) and a battery cell B1 (second battery cell) arranged side by side in the left-right direction (first direction) orthogonal to the axial direction, and a battery cell C1 (third battery cell) arranged at a position separated from the battery cells A1 and B1 in the front-rear direction (second direction) orthogonal to the axial direction and the left-right direction (first direction). The chamber 36 is provided between the battery cell A1 and the battery cell B1 in the left-right direction (first direction) and is adjacent to the battery cell A1, the battery cell B1, and the battery cell C1. With such a configuration, since the battery cells A1, B1, and C1 are not arranged side by side in the left-right direction, the size of the battery module 10 in the left-right direction can be reduced as compared with the configuration in which these three battery cells A1, B1, and C1 are arranged side by side in the left-right direction. Moreover, the chamber 36 can be efficiently provided by utilizing the space between the battery cell A1 and the battery cell B1.

[0051] <Other embodiments> The present invention is not limited to the embodiments described above and in the drawings. For example, the following embodiments are also included in the technical scope of the present invention. · In the first embodiment, the openings 31B and 31C are provided on both the upper and lower sides of the main body 31, but an opening may be provided on one side in the vertical direction. · In the first embodiment, the cooling water for cooling the inside of the battery module 10 is exemplified as the liquid for temperature-adjusting the battery module 10, but when warming the inside of the battery module 10, a relatively warm liquid may be used. · In the first embodiment, the gaskets 40 and 50 may have the same shape and may be configured as a common member. Similarly, the covers 60 and 70 may have the same shape and may be configured as a common member. · In the first embodiment, the plurality of battery cells 20 constitute three cell groups (first cell group A, second cell group B, and third cell group C) arranged side by side in the front-rear direction, but may constitute four or more cell groups. ·In Example 1, the three cell groups (the first cell group A, the second cell group B, and the third cell group C) were composed of four battery cells, but they may be composed of one, two, four or more battery cells 20.

Explanation of Signs

[0052] 10: Battery module 20: Battery cell 21: Lower end 22: Upper end 30: Accommodation part 31: Main body part 31A: Accommodation space 31B, 31C: Opening 31D: Protrusion 32: Cell space 32B: Cell space 32C: Cell space 33: Inner frame part 34: Supply path 35: Discharge path 36: Chamber 36A: Opening 36B, 36C: Opening part 37: Protrusion 37A, 37B: Slit 40: Gasket 41: Plate part 42: Seal part 45: Hole 50: Gasket 51: Plate part 52: Seal part 55: Hole 60: Cover 61: Plate part 62: Recess 63: Hole 70: Cover 71: Plate part 72: Recess 73: Hole 80: Bus bar 81: Main body part 82: Tab part 90: Bus bar 92: Tab part 100: Bolt 110: Nut A1: Battery cell (first battery cell) A: First cell group B1: Battery cell (second battery cell) B: Second cell group C1: Battery cell (third battery cell) C4: Battery cell C: Third cell group

Claims

1. A battery module that performs temperature adjustment using a fluid, a plurality of cylindrical battery cells, a housing portion that houses the plurality of battery cells in a state where the axial directions of the plurality of battery cells are parallel, and into which the fluid is supplied, a supply path that supplies the fluid to the housing space, comprising: the housing portion has a chamber that communicates with the supply path and the housing space, the chamber is a battery module that reduces the flow rate of the fluid supplied from the supply path and supplies the fluid to the housing space.

2. the chamber has a plurality of openings leading to the housing space, the battery module according to claim 1, wherein the plurality of openings supply the fluid to different positions in the housing space, respectively.

3. the battery module according to claim 2, wherein the opening is slit-shaped.

4. the plurality of battery cells a first battery cell and a second battery cell arranged side by side in a first direction orthogonal to the axial direction, a third battery cell arranged at a position separated from the first battery cell and the second battery cell in a second direction orthogonal to the axial direction and the first direction, including: the battery module according to any one of claims 1 to 3, wherein the chamber is provided between the first battery cell and the second battery cell in the first direction and is adjacent to the first battery cell, the second battery cell, and the third battery cell.

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