WO2024190621A1

WO2024190621A1 - Battery module

Info

Publication number: WO2024190621A1
Application number: PCT/JP2024/008850
Authority: WO
Inventors: 恭介三好; 政夫川田
Original assignee: 本田技研工業株式会社
Priority date: 2023-03-10
Filing date: 2024-03-07
Publication date: 2024-09-19

Abstract

Provided is a battery module of which the strength and rigidity are increased and that has improved cooling performance.　The battery module comprises: a plurality of battery cells that are formed in a substantially columnar shape; a plate-like upper holder that supports the upper surfaces of the battery cells; and a plate-like lower holder that supports the lower surfaces of the battery cells. The upper holder and the lower holder each include, in a plan view: a plurality of substantially columnar first protruding portions each provided in a position in which there is a space surrounded by three battery cells; and a plurality of rib portions formed to rise at the outer edge portion. The battery cells are arranged between the upper holder and the lower holder. The first protruding portions are arranged between the battery cells. The outer peripheral surfaces of the battery cells positioned on the outer-most side are held by the rib portions to form a cell assembly.

Description

Battery Module

The present invention relates to a battery module.

Patent Document 1 discloses a battery module that has multiple cylindrical battery cells. In this battery module, multiple battery cells are stored inside a pipe-shaped member, and the pipe-shaped member is joined to a holder on the top and bottom to form the battery module.

International Publication No. WO 2012/164828

Battery modules that house multiple battery cells inside pipe-shaped members, such as the battery module described in Patent Document 1, have issues in that heat generated by the battery cells tends to build up and the battery cell holding structure has low strength.
An object of the present invention is to provide a battery module that can improve strength, rigidity, and cooling performance.

This specification includes the entire contents of Japanese Patent Application No. 2023-037199 filed on March 10, 2023.
The battery module of the present invention comprises a plurality of battery cells formed in an approximately cylindrical shape, a flat upper holder supporting the upper surfaces of the battery cells, and a flat lower holder supporting the lower surfaces of the battery cells, and the upper holder and the lower holder have a plurality of approximately cylindrical first protrusions provided at a position where there is a space surrounded by three of the battery cells in a plan view, and a plurality of rib portions formed upright on the outer edges, the battery cells are arranged in a row between the upper holder and the lower holder, the first protrusions are respectively arranged between the battery cells, and a cell assembly is formed in a state in which the outer peripheral surface of the outermost battery cell is held by the rib portions.

According to the present invention, the first protrusion supports the battery cells while maintaining the distance between each battery cell. In addition, because the upper holder and the lower holder are formed in a flat plate shape, the side surfaces of the battery cells are exposed. This makes it possible to provide a battery module that can improve strength, rigidity, and cooling performance.

FIG. 1 is a perspective view of a battery module according to a first embodiment. FIG. 2 is a perspective view of the battery cell, upper holder, and lower holder according to embodiment 1. FIG. FIG. 3 is a cross-sectional plan view taken along line III of FIG. FIG. 4 is a cross-sectional view taken along line IV in FIG. FIG. 5 is a perspective view of a battery cell according to the second embodiment. FIG. 6 is a schematic diagram of an engagement portion according to the second embodiment. FIG. 7 is a schematic diagram of an engagement portion according to another embodiment. FIG. 8 is a cross-sectional view of a battery module according to the third embodiment.

[First embodiment]
Hereinafter, a battery module 1 according to the first embodiment will be described with reference to Fig. 1 and Fig. 2. For convenience of explanation, arrows marked with FR, UP, and LH corresponding to the forward, upward, and left directions in the text, respectively, are shown in each figure.

Figure 1 is a perspective view of a battery module 1. Figure 2 is a perspective view of a battery cell 10, an upper holder 16, and a lower holder 18. For the purpose of explanation, Figure 2 shows the upper holder 16 and the lower holder 18 expanded vertically.

The battery module 1 comprises a cell assembly 12 composed of a plurality of battery cells 10, and a heat shrink film 28 that binds the outer peripheral surface 12R of the cell assembly 12. The heat shrink film 28 is an example of a "cell holding member."

The battery cells 10 are arranged in groups of three along the row heading forward, for a total of four rows to the left. In other words, 12 battery cells 10 are arranged. The rows heading forward are called, from the right, the first row L1, the second row L2, the third row L3, and the fourth row L4.

The battery cells 10 in the first row L1 and the third row L3 are arranged in the same position when viewed from the left side. The battery cells 10 in the second row L2 and the fourth row L4 are arranged in the same position when viewed from the left side. The battery cells 10 in the second row L2 are arranged so as to be shifted from the battery cells 10 in the first row L1 by the width of the radius of the battery cells 10.

The outer peripheral surface 12R of the cell assembly 12 is the side of the battery cell 10 that is exposed and not covered by other battery cells 10. The heat shrink film 28 covers the outer peripheral surface 12R and bundles the multiple battery cells 10 together. The heat shrink film 28 is positioned in the center of the battery cells 10 in the up-down direction. The heat shrink film 28 shrinks when heat is applied, making it possible to tightly bind the battery cells 10.

The battery module 1 includes a flat upper holder 16 that covers the upper surface of the battery cell 10, and a flat lower holder 18 that covers the lower surface of the battery cell 10.

The upper holder 16 has multiple holes 30 that expose the upper surfaces 10m of the battery cells 10. The lower holder 18 also has multiple holes 30.

The upper holder 16 has multiple rib portions 20 that cover the outer peripheral surface 12R of the cell assembly 12. The rib portions 20 are formed to extend downward from the plane of the upper holder 16, and are curved to fit the side surfaces of the battery cells 10. In other words, the cell assembly 12 is formed with the outer peripheral surface of the outermost battery cell 10 held by the rib portions.

The rib portion 20 can prevent the battery cell 10 from shifting left and right or front and rear. The lower holder 18 has a rib portion 20, just like the upper holder 16.

Of the multiple rib portions 20, the rib portion 20A that covers the right side surface of the first row L1 is formed as a continuous surface that covers the entire right side surface.

The upper holder 16 has multiple, roughly cylindrical first protrusions 24 and multiple second upper protrusions 26 that are longer than the first protrusions 24 and extend downward. The first protrusions 24 are erected perpendicular to the plane of the upper holder 16 and are formed to fit into the space S between the three battery cells 10.

The lower holder 18 has a plurality of first protrusions 24, similar to the upper holder 16. The lower holder 18 has a second lower protrusion 27 that extends upward and has an upper end located above the lower end of the second upper protrusion 26.

In particular, each first protrusion 24 in the space S surrounded by the three battery cells 10 is formed so as to overlap with both the upper holder 16 and the lower holder 18 in a plan view. In addition, the first protrusion 24 is formed with a diameter that allows it to abut against the battery cell 10.

On the outer periphery of the upper holder 16, starting from the front and closest to the rib portion 20A, the second upper protrusion 26, the first protrusion 24, the second upper protrusion 26, the first protrusion 24, the second upper protrusion 26, the first protrusion 24, the first protrusion 24, the second upper protrusion 26, and the first protrusion 24 are arranged in this order. The upper holder 16 has four second upper protrusions 26 and five first protrusions 24 on the outside.

On the outer periphery of the lower holder 18, starting from the front and closest to the rib portion 20A, the first protrusion 24, the second lower protrusion 27, the first protrusion 24, the second lower protrusion 27, the first protrusion 24, the first protrusion 24, the second lower protrusion 27, the first protrusion 24, and the second lower protrusion 27 are arranged in this order. There are four second lower protrusions 27 and five first protrusions 24 on the outside of the lower holder 18.

In other words, on the outer periphery of the upper holder 16 and the lower holder 18, the first protrusion 24 and the second upper protrusion 26, and the first protrusion 24 and the second lower protrusion 27 are arranged to overlap in a plan view.

The combined width of the first protrusion 24 and the second upper protrusion 26, and the combined width of the first protrusion 24 and the second lower protrusion 27 are slightly smaller than the width from the upper holder 16 to the lower holder 18. Therefore, the first protrusion 24 and the second upper protrusion 26, and the first protrusion 24 and the second lower protrusion 27 are arranged to overlap in a plan view, but the tips of each part do not interfere with each other.

The tip 24A of the first protrusion 24 is tapered toward the tip, i.e. tapered.

The second upper protrusion 26 has a protrusion 26A at its tip that protrudes outward from the cell assembly 12, and the protrusion 26A is formed so as to abut against the heat shrink film 28. The second lower protrusion 27 has a protrusion 27A at its tip that protrudes outward from the cell assembly 12, and the protrusion 27A is formed so as to abut against the heat shrink film 28. The protrusion 26A of the upper holder 16 abuts against a lower end 28D of the heat shrink film 28. The protrusion 27A of the lower holder 18 abuts against an upper end 28U of the heat shrink film 28. That is, the heat shrink film 28 is disposed between the

protrusions

26A and 27A.
The

protrusions

26A and 27A are examples of the "protrusions."

FIG. 3 is a cross-sectional view taken along plane III in FIG. 1. FIG. 3 is a view taken from above toward below in FIG. 1. Plane III is located approximately in the center of the battery cell 10 in the up-down direction. FIG. 4 is a cross-sectional view taken along plane IV in FIG. 1. FIG. 4 is a view taken from the rear toward the front in FIG. 1. Plane IV is located approximately in the center of the battery cell 10 in the front-to-rear direction. In FIG. 4, configuration other than that visible in the cross section is omitted.

The first protrusions 24 located in the space S abut against the outer surfaces of the three battery cells 10. The battery cells 10 in the center of the second row L2 and the center of the third row L3 abut against a total of six first protrusions 24. The first protrusions 24 maintain the posture of the battery cells 10. The first protrusions 24 maintain a constant distance between each battery cell 10, and position the battery cells 10.

As shown in FIG. 4, among the first protrusions 24 positioned in the space S, a gap G is provided between two first protrusions 24 that overlap vertically.

The operation of the battery module 1 configured as above will now be described.
The battery cell 10 is positioned by the rib portion 20, first protrusion 24, and second lower protrusion 27 provided on the lower holder 18, and is installed at a predetermined position on the lower holder 18. Next, the upper holder 16 is positioned by the first protrusion 24 entering the space S, and is installed on the upper surface of the battery cell 10. Furthermore, a heat shrink film 28 is provided so as to cover the second upper protrusion 26 and the second lower protrusion 27, and shrinks when heat is applied, binding and holding the battery cell 10.

The upper holder 16 and the lower holder 18 are formed in a flat plate shape, so that they are not thick, are lightweight, and take up little space.
The tip portion 24A is tapered, which improves workability when fitting the upper holder 16 or the lower holder 18 to the cell assembly 12. In particular, workability is good when inserting the first protrusion 24 into the space S surrounded by the three battery cells 10.

If the upper holder 16 is shifted upward, the protrusion 26A gets caught on the heat shrink film 28. If the lower holder 18 is shifted downward, the protrusion 27A gets caught on the heat shrink film 28. This prevents the various parts of the battery module 1 from shifting and improves its strength.

The temperature of the battery cells 10 can rise during operation. The gap G prevents heat from building up between the battery cells 10, improving cooling performance.

As described above, the battery module 1 according to this embodiment comprises a plurality of battery cells 10 formed in an approximately cylindrical shape, a flat upper holder 16 supporting the upper surfaces 10m of the battery cells 10, and a flat lower holder 18 supporting the lower surfaces of the battery cells 10. In a plan view, the upper holder 16 and the lower holder 18 comprise a plurality of approximately cylindrical first protrusions 24 provided at a position where there is a space S surrounded by three battery cells 10, and a plurality of rib portions 20 formed on the outer edges. The battery cells 10 are arranged in a row between the upper holder 16 and the lower holder 18, and the first protrusions 24 are respectively arranged between the battery cells 10. The cell assembly 12 is formed in a state in which the outer peripheral surface 12R of the outermost battery cell 10 is held by the rib portions 20.
According to this configuration, the first protrusions 24 support the battery cells 10 while maintaining the distance between the battery cells 10. Furthermore, because the upper holder 16 and the lower holder 18 are formed in a flat plate shape, the side surfaces of the battery cells 10 are exposed. This improves the strength, rigidity, and cooling performance of the battery module 1.

Furthermore, the length of the rib portion 20 in the axial direction of the battery cell 10 is shorter than the length of the first protrusion portion 24 .
According to this configuration, the strength and rigidity of the battery module 1 can be improved while reducing the weight of the battery module 1 .

In addition, the outer periphery of the upper holder 16 is provided with a second upper protrusion 26 extending downward, and the outer periphery of the lower holder 18 is provided with a second lower protrusion 27 extending upward and having a tip located higher than the tip of the second upper protrusion 26 of the upper holder 16, and a heat shrink film 28 (cell retaining member) that retains the outer periphery 12R of the cell assembly 12 is provided between the tips of the second upper protrusion 26 and the second lower protrusion 27.
According to this configuration, the cell assembly 12 can be tightly bound and held by the heat shrink film 28, thereby improving the strength and rigidity of the battery module 1.

At the tips of the second upper protrusion 26 and the second lower protrusion 27, a convex portion 26A (protrusion) and a convex portion 27A (protrusion) that protrude to the outside of the cell assembly 12 are formed, respectively, and a heat shrink film 28 is arranged between the convex portion 26A and the convex portion 27A.
According to this configuration, heat shrink film 28 is caught by

protrusions

26A, 27A, so that the strength and rigidity of battery module 1 can be improved.

[Embodiment 2]
Hereinafter, the battery module 100 according to the second embodiment will be described with reference to Fig. 5, Fig. 6, and Fig. 7. Note that the description of matters that overlap with the description of the first embodiment will be omitted.

The upper holder 16 has a plurality of third protrusions 102. The lower holder 18 has a plurality of fourth protrusions 104. The third protrusions 102 and the fourth protrusions 104 are arranged in overlapping positions when viewed from above, and are connected via an engagement portion 106.

FIG. 6 is an enlarged cross-sectional view of the engagement portion 106. The tip 102A of the third protrusion 102 is formed in a concave shape, and the tip 104A of the fourth protrusion 104 is formed in a convex shape. The engagement portion 106 is formed by fitting the tip 102A and the tip 104A together, thereby holding the upper holder 16 and the lower holder 18 together.

The configuration of the engaging portion 106 is not limited to the above, and it is sufficient if it can engage the third protrusion 102 and the fourth protrusion 104. Therefore, an example of the engaging portion 106 according to another embodiment is shown. FIG. 7 is an enlarged cross-sectional view of the engaging portion 106 according to another embodiment. The tip 102A of the third protrusion 102 is formed in a claw shape, and the tip 104A of the fourth protrusion 104 is formed in a claw shape. The engaging portion 106 is formed by the tip 102A and the tip 104A coming into contact with each other, thereby holding the upper holder 16 and the lower holder 18.

The operation and the like of the battery module 100 according to the second embodiment configured as above will be described.
The battery cell 10 is positioned by the rib portion 20, the first protrusion 24, and the fourth protrusion 104 provided on the lower holder 18, and is installed at a predetermined position on the lower holder 18. Next, the upper holder 16 is positioned by the first protrusion 24 entering the space S, and is installed on the upper surface of the battery cell 10. Furthermore, the cell assembly 12 is held by aligning the positions of the third protrusion 102 and the fourth protrusion 104 and engaging the engagement portion 106.
If the upper holder 16 or the lower holder 18 becomes misaligned, the engagement portion 106 holds the upper holder 16 and the lower holder 18 together, thereby preventing the misalignment.
Other operations and the like are similar to those of the first embodiment.

As described above, the battery module 100 of embodiment 2 has a third protrusion 102 extending downwardly from the outer periphery of the upper holder 16, and a fourth protrusion 104 extending upwardly from the outer periphery of the lower holder 18, and is provided with an engagement portion 106 connecting a tip portion 102A of the third protrusion 102 and a tip portion 104A of the fourth protrusion 104.
According to this configuration, the upper holder 16 and the lower holder 18 are held by the engaging portion 106, so that the strength and rigidity of the battery module 100 can be improved.

Of the third protruding portion 102 and the fourth protruding portion 104, a tip portion 102A of the third protruding portion 102 is formed in a concave shape, and a tip portion 104A of the fourth protruding portion 104 is formed in a convex shape.
According to this configuration, the upper holder 16 and the lower holder 18 are held by the engaging portion 106, so that the strength and rigidity of the battery module 100 can be improved.

Furthermore, of the third protrusion 102 and the fourth protrusion 104, the tip 102A of the third protrusion 102 is formed in a claw shape, and the tip 104A of the fourth protrusion 104 is formed in a claw shape and abuts against the tip 102A.
According to this configuration, the upper holder 16 and the lower holder 18 are held by the engaging portion 106, so that the strength and rigidity of the battery module 100 can be improved.

[Embodiment 3]
Hereinafter, a battery module 1000 according to the third embodiment will be described with reference to Fig. 8. Note that descriptions of matters that overlap with the descriptions of the first and second embodiments will be omitted.

FIG. 8 is a cross-sectional view of a battery module 1000 according to embodiment 3. The battery module 1000 is configured by arranging four battery modules 1 according to embodiment 1 adjacent to each other in a plan view. Note that the number of battery modules 1 constituting the battery module 1000 can be changed as appropriate.

The contact portion T is the portion where the protrusion 26A contacts the other battery module 1. Although not shown in the figure, the protrusion 27A also contacts the ionization module 1 in a similar manner.

The

protrusions

26A, 27A protrude outward from the cell assembly 12. The

protrusions

26A, 27A can determine the distance between the battery module 1 and the outer surface of another adjacent battery module 1. For example, by increasing the thickness of the

protrusions

26A, 27A, the distance between the battery modules 1 can be increased, improving cooling performance and insulation between the battery modules 1. On the other hand, by decreasing the thickness of the

protrusions

26A, 27A, the distance between the battery modules 1 can be decreased, making it possible to miniaturize the battery module 1000 and realize electrical connection between each battery module 1.

The operation of the battery module 1000 configured as described above will now be explained.

In the third embodiment, the battery module 1 is configured in a similar manner to the description of the operation and the like of the first embodiment.
In the battery module 1000, the battery modules 1 according to the first embodiment are arranged so as to maximize the density of the battery modules 1 in a plan view. When arranging a plurality of battery modules 1, the

protrusions

26A and 27A may be used as positioning members that determine the distance between each of the battery modules 1.

The battery module 1 may be the battery module 100 according to the second embodiment. In that case, if the thickness of the engagement portion 106 is changed instead of changing the thickness of the

protrusions

26A and 27A, the same action and effect as in the third embodiment can be achieved.

[Other embodiments]
The above-described embodiment is an example of one aspect of the present invention, and can be modified and applied as desired without departing from the spirit of the present invention. In addition, the first, second, and third embodiments can be combined in any manner to form a new embodiment.

In each of the above embodiments, the gap G has been described as the space between the two first protrusions 24. The gap G is not limited to being a simple space, and may be filled with, for example, an adhesive to improve strength, or a heat transfer material to improve cooling performance.

Furthermore, in each of the above embodiments, it has been explained that the first protrusion 24 is formed with a diameter that allows it to abut against the battery cell 10. The diameter of the first protrusion 24 can be changed as appropriate. For example, by increasing the diameter of the first protrusion 24, the distance between the battery cells 10 can be increased, improving cooling performance and improving insulation between the battery cells 10. On the other hand, by decreasing the diameter of the first protrusion 24, the distance between the battery cells 10 can be decreased, making it possible to miniaturize the battery module 1 and realize electrical connection between each battery cell 10.

[Configuration supported by the above embodiment]
The above embodiment supports the following configurations.

(Configuration 1) A battery module comprising a plurality of battery cells formed in an approximately cylindrical shape, a flat upper holder supporting the top surfaces of the battery cells, and a flat lower holder supporting the undersides of the battery cells, wherein the upper holder and the lower holder have a plurality of approximately cylindrical first protrusions provided at a position where, in a plan view, there is a space surrounded by three of the battery cells, and a plurality of rib portions formed upright on the outer edges, the battery cells are arranged in a row between the upper holder and the lower holder, each of the first protrusions is arranged between the battery cells, and a cell assembly is formed with the outer peripheral surface of the outermost battery cell being held by the rib portions.
According to this, the first protrusions support the battery cells while maintaining the distance between the battery cells. Also, since the upper holder and the lower holder are formed in a flat plate shape, the side surfaces of the battery cells are exposed. This improves the strength, rigidity, and cooling performance of the battery module.

(Configuration 2) The battery module according to configuration 1, wherein a length of the rib portion in the axial direction of the battery cell is shorter than a length of the first protrusion portion.
This makes it possible to reduce the weight of the battery module while improving the strength and rigidity of the battery module.

(Configuration 3) A battery module as described in configuration 1 or 2, comprising a second upper protrusion extending downwardly on the outer periphery of the upper holder, and a second lower protrusion extending upwardly on the outer periphery of the lower holder and having a tip located above the tip of the second upper protrusion of the upper holder, and a cell retaining member for retaining the outer periphery of the cell assembly is provided between the tips of the second upper protrusion and the second lower protrusion.
According to this, the cell assembly can be held by the cell holding member, thereby improving the strength and rigidity of the battery module.

(Configuration 4) A battery module described in configuration 3, wherein a protrusion protruding outwardly of the cell assembly is formed at the tip of the second upper protrusion and the second lower protrusion, and the cell holding member is disposed between the protrusions.
According to this, the cell assembly can be held by the cell holding member, thereby improving the strength and rigidity of the battery module.

(Configuration 5) A battery module as described in configuration 1 or 2, further comprising a third protrusion extending downwardly from the outer periphery of the upper holder, a fourth protrusion extending upwardly from the outer periphery of the lower holder, and an engagement portion connecting a tip of the third protrusion and a tip of the fourth protrusion.
According to this, the upper holder and the lower holder are held by the engaging portion, thereby improving the strength and rigidity of the battery module.

(Configuration 6) The battery module according to configuration 5, wherein one of the third protrusion and the fourth protrusion has a concave tip and the other has a convex tip.
According to this, the upper holder and the lower holder are held by the engaging portion, thereby improving the strength and rigidity of the battery module.

(Configuration 7) A battery module as described in configuration 5, wherein one of the third protrusions and the fourth protrusions has a tip portion formed in a claw shape, and the other has a tip portion formed in a claw shape and abuts against the one tip portion.
According to this, the upper holder and the lower holder are held by the engaging portion, thereby improving the strength and rigidity of the battery module.

REFERENCE SIGNS

LIST

1, 100, 1000 Battery module 10 Battery cell 12 Cell assembly 12R Outer circumferential surface 16 Upper holder 18 Lower holder 20 Rib portion 24 First protruding portion 24A Tip portion 26 Second upper protruding portion 26A Convex portion (protruding portion)
27 Second lower protrusion 27A Convex portion (protrusion)
28 Heat-shrinkable film

28D Lower end

28U Upper end 102 Third protrusion 102A Tip 104 Fourth protrusion 104A Tip 106 Engagement part

Claims

The battery pack includes a plurality of battery cells formed in a substantially cylindrical shape, a flat upper holder that supports upper surfaces of the battery cells, and a flat lower holder that supports lower surfaces of the battery cells,
the upper holder and the lower holder each include a plurality of first protrusions each having a substantially cylindrical shape and provided at a position where there is a space surrounded by the three battery cells in a plan view, and a plurality of rib portions formed upright on outer edges of the holder;
the battery cells are arranged side by side between the upper holder and the lower holder, the first protrusions are arranged between the battery cells, and a cell assembly is formed in a state in which an outer peripheral surface of the outermost battery cell is held by the rib portion.
Battery module.
a length of the rib portion in the axial direction of the battery cell is shorter than a length of the first protrusion portion;
The battery module according to claim 1 .
A second upper protrusion extending downward is provided on an outer periphery of the upper holder,
a second lower protrusion extending upward from an outer periphery of the lower holder and having a tip located higher than a tip of the second upper protrusion of the upper holder;
a cell holding member that holds an outer peripheral surface of the cell assembly is provided between a tip of the second upper protrusion and a tip of the second lower protrusion.
The battery module according to claim 1 or 2.
a protrusion protruding outward from the cell assembly is formed at a tip of the second upper protrusion and the second lower protrusion;
The cell retaining member is disposed between the protrusions.
The battery module according to claim 3 .
a third protrusion extending downward from an outer periphery of the upper holder;
a fourth protrusion extending upward from an outer periphery of the lower holder;
An engagement portion is provided to connect a tip end portion of the third protrusion and a tip end portion of the fourth protrusion.
The battery module according to claim 1 or 2.
One of the third protrusion and the fourth protrusion has a concave tip, and the other has a convex tip.
The battery module according to claim 5 .
One of the third protrusion and the fourth protrusion has a tip portion formed in a claw shape, and the other has a tip portion formed in a claw shape and abuts against the one tip portion.
The battery module according to claim 5 .