JP6879247B2 - Battery module - Google Patents

Description

The present invention relates to a battery module including a battery cell and a case for accommodating and holding the battery cell.

Various types of battery modules including a battery cell and a case for accommodating and holding the battery cell have been conventionally known. According to this type of battery module, by protecting the battery cell with a case, there is an advantage that the battery cell can be smoothly charged and discharged while being compatible with various external environments.

Separating the battery cell from the outside world is one of the important functions of the case in the battery module. For example, when the battery module is installed outdoors, it is possible to prevent the battery cells from being exposed to rainwater or being exposed to extremely high or low temperatures by blocking rain and wind with a case.

However, by separating the battery cell from the outside world depending on the case, it may be difficult to say that the atmosphere in which the battery cell is placed is optimal for the charge / discharge reaction. For example, if the air flow inside and outside the case is small, the temperature inside the case rises due to heat generated by the charge / discharge reaction of the battery cells. If the temperature inside the case is excessively high, it becomes difficult to adequately charge and discharge the battery cells. Therefore, a technique for adding a mechanism for introducing air into the case from the outside world to the battery module has been proposed.

For example, Patent Document 1 introduces a battery pack including a blower fan for introducing air from the outside to the inside of the case. The battery pack of Patent Document 1 has a plurality of battery cells, a blower fan, and a housing, and a plurality of battery cells are arranged in a circumferential shape inside a substantially cylindrical housing. In the battery pack of Patent Document 1, a tubular intake port is provided at one end in the axial direction of the housing, a tubular exhaust port is provided at the other end in the axial direction, and a plurality of batteries arranged in a circumferential shape. The blower fan is located in the center of the battery cell. By rotationally driving the blower fan, the air introduced from the outside of the case to the inside through the intake port flows through the gap between the battery cells and is discharged to the outside of the case through the exhaust port.

However, in recent years, the applications of battery cells have been diversified, and further technological innovation is desired for battery cells. Similarly, further technological innovation is desired for a battery module including a battery cell and a case.

Japanese Unexamined Patent Publication No. 2015-18619

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a novel battery module including a battery cell and a case.

The battery module of the present invention that solves the above problems
A battery cell and a case for accommodating and holding the battery cell inside are provided.
The case is rotatable around a rotation axis and can be rotated.
The case has two end walls forming both end faces in the rotation axis direction and a peripheral wall forming an outer peripheral surface.
The peripheral wall is a battery module having a peripheral wall vent that communicates with the inside and outside of the case.

The battery module of the present invention is a novel battery module capable of introducing air from the outside to the inside of the case.

It is an exploded perspective view which shows typically the battery module of Example 1. FIG. It is explanatory drawing which shows typically the air flow in the battery module of Example 1. FIG. It is an enlarged view of the main part of FIG. FIG. 5 is an enlarged perspective view of a main part of the battery module of the first embodiment. FIG. 5 is an enlarged perspective view of a main part of the battery module of the second embodiment. It is an enlarged sectional view of the main part of the battery module of Example 3 at the same position as FIG. It is an enlarged sectional view of the main part of the battery module of Example 4 at the same position as FIG. It is an enlarged sectional view of the main part of the battery module of Example 5 at the same position as FIG. It is an enlarged sectional view of the main part of the battery module of Example 6 at the same position as FIG. It is explanatory drawing which shows typically the state which the battery module of Example 6 was seen from the axial direction. It is a perspective view which shows typically the battery module of Example 8. FIG. 5 is an enlarged cross-sectional view of a main part schematically showing a case in the battery module of the eighth embodiment.

Hereinafter, the battery module of the present invention will be specifically described.

The battery module of the present invention includes a battery cell and a case.

The case houses and holds the battery cells inside, and can rotate around the rotation axis. Further, the case has two end walls forming both end faces in the direction of the rotation axis and a peripheral wall forming an outer peripheral surface, of which the peripheral wall has a peripheral wall vent for communicating the inside and outside of the case. Hereinafter, unless otherwise specified, the rotation axis direction is simply referred to as an axial direction, and the direction orthogonal to the axial direction is simply referred to as an axis perpendicular direction.

The shape of the case may satisfy the above requirements. For example, the distance from the rotation axis to the peripheral wall may or may not be constant. Further, the cross section of the case in the direction perpendicular to the axis may or may not be constant in the axial direction.

However, since the case in the battery module of the present invention rotates, in order to efficiently rotate the case, the case has a cylindrical shape centered on the rotation axis or a regular polygonal axis perpendicular to the rotation axis. It is preferably tubular with a directional cross section. Further, it is preferable that the cross section of the case in the direction perpendicular to the axis is constant along the axis direction.

The peripheral wall of the case has a peripheral wall vent that communicates with the inside and outside of the case. The inside and outside of the case are partially partitioned by a peripheral wall and two end walls, and since the case rotates in the battery module of the present invention, there is a difference in flow velocity between the air inside the case and the air outside the case. Is thought to occur. Due to the difference in flow velocity, the air outside the case is introduced into the case through the peripheral wall vent, or the air inside the case is discharged to the outside of the case through the peripheral wall vent. Air circulates inside and outside. The air circulating inside and outside the case exchanges heat with the battery cell when it flows in the vicinity of the battery cell. Therefore, according to the battery module of the present invention, the battery cell can be cooled or heated by the air, and the temperature of the battery cell can be adjusted within a range suitable for charging and discharging. Unlike the battery pack introduced in Patent Document 1, the battery module of the present invention does not require an air introduction device such as a blower fan because the above-mentioned air flow is generated by the rotation of the case itself.

The battery cell housed in the case may or may not rotate together with the case.

As described above, the peripheral wall vent functions as an inlet when the air outside the case is introduced into the case, or as an outlet when the air inside the case is discharged to the outside of the case. .. Whether the peripheral wall vent functions as an inlet or an outlet is determined by the peripheral structure of the peripheral wall vent and the direction of rotation of the case. The peripheral structure of the peripheral wall vent will be described in detail in the section of Examples.

The peripheral wall may have only one peripheral wall vent, but it is preferable to have a plurality of peripheral walls. When the peripheral wall has a plurality of peripheral wall vents, it is preferable that the peripheral wall vents are distributed so that air can exchange heat evenly with the battery cells inside the case. Specifically, when the battery module of the present invention includes a plurality of battery cells, the peripheral wall vents are preferably arranged evenly with respect to the plurality of battery cells, and are located at positions corresponding to the respective battery cells. It is more preferable to provide.

The case in the battery module of the present invention may have a double or more multiple structure. For example, the case may have a double structure of an inner case and an outer case. In this case, the battery cell may be housed and held between the outer case and the inner case, or may be housed and held inside the inner case. When the battery cell is housed and held inside the inner case, the inner case and the outer case are arranged outside the battery cell. In this case, in order to efficiently circulate the air, it is preferable to provide the peripheral wall vents on both the peripheral wall of the outer case and the peripheral wall of the inner case. In that case, it is preferable that the peripheral wall vents on the peripheral wall of the outer case and the peripheral wall vents on the peripheral wall of the inner case are arranged apart from each other in the circumferential direction of the case. By doing so, for example, even if the battery module of the present invention is exposed to rainwater and the rainwater enters the peripheral wall vent of the outer case, the rainwater does not easily enter the peripheral wall vent of the inner case, and the battery cell Hard to be exposed to rainwater.

In addition to the peripheral wall vent, the case may be provided with an opening that communicates with the inside and outside of the case. For example, an opening communicating the inside and outside of the case may be provided in at least one of the end walls. The opening provided in the end wall is referred to as an end wall vent.

The end wall vent can serve as an air outlet from the inside of the case to the outside of the case when the air outside the case is introduced into the case through the peripheral wall vent. Further, when the air inside the case is discharged to the outside of the case through the peripheral wall vent, it can be an air inlet from the outside of the case to the inside of the case. By providing such an opening in the end wall, the air flow path inside the case becomes simple and compact, the generation of turbulent flow inside the case can be suppressed, and the heat exchange between the air and the battery cell is efficient. Can be done well.

The end wall vent may be provided on the end wall, and its position is not particularly limited, but it is preferably provided at or near the center of rotation of the case.

The case may be rotatable about a rotation axis, and its rotation drive mechanism is not particularly limited. For example, the case can be rotated by a known rotary drive mechanism such as an electric motor. Alternatively, the case may be manually rotated instead of the rotation drive mechanism. The case may continue to rotate while the battery cell is being charged and discharged, or may be repeatedly rotated and stopped at an arbitrary timing.

The case may actually have a rotating shaft having a rod-like shape and may rotate by receiving a driving force from the rotating driving mechanism on the rotating shaft, but the case is not limited to this. For example, the case in the battery module of the present invention may rotate by receiving a driving force by a rotation driving mechanism on the peripheral wall. That is, the rotating shaft in the battery module of the present invention may be a physical shaft or a virtual shaft having no substance. In either case, the case is similar in that it rotates about a rotation axis.

The material constituting the case may be any material, but for the purpose of protecting the battery cell and reducing the influence of impact, outside air temperature, etc., it is preferable that the material has excellent rigidity and low thermal conductivity. Further, in consideration of safety, it is preferable that the material has an insulating property. Specifically, the case is a resin material typified by a polyamide (PA) resin, an acrylonitrile-butadiene-styrene copolymer synthetic (ABS) resin, a polyphenylene sulfide (PPS) resin, or at least one of the resin materials. It is preferably composed of a composite material mixed with glass fiber or the like.

The battery module of the present invention may include only one battery cell, or may include a plurality of battery cells. The battery module of the present invention including a plurality of battery cells further includes a bus bar for electrically connecting each battery cell, a separator for partially blocking the electrical connection of each battery cell, and fixing the battery cell in a case. It may include a battery module component such as a cell fixing member. Each battery cell may be connected in series or in parallel.

The battery cell is formed by accommodating battery components such as a positive electrode, a negative electrode, and an electrolytic solution in a battery container. The battery components in the battery cell may be appropriately designed according to the type of battery cell to be provided in the battery module of the present invention, and are not particularly limited in the present invention. The battery cell is housed inside the case as a cell cell partitioned by a battery container. Therefore, it can be said that the battery components are housed in the battery container and further housed in the case.

The battery container may be of any shape as long as it can be accommodated in the case, and for example, various shapes such as a cylindrical type, a square type, a coin type, and a laminated type can be used. The material of the battery container is also not particularly limited.

When the battery module of the present invention includes a plurality of battery cells, it is preferable that the battery cells have the same size and are arranged at equal intervals in the circumferential direction about the rotation axis of the case. By doing so, an air flow can be formed between the adjacent battery cells, and the case accommodating the battery cells can be smoothly rotated.

Hereinafter, the battery module of the present invention will be described with reference to specific examples.

Unless otherwise specified, the numerical range "x to y" described in the present specification includes the lower limit x and the upper limit y. Then, a numerical range can be constructed by arbitrarily combining these upper and lower limit values and the numerical values listed in the embodiment. Further, the numerical value arbitrarily selected from the numerical range can be set as the upper limit value and the lower limit value.

(Example 1)
FIG. 1 is an exploded perspective view schematically showing the battery module of the first embodiment. 2 and 3 are explanatory views schematically showing the air flow in the battery module of the first embodiment. More specifically, FIG. 2 schematically shows a state in which the battery module of the first embodiment is cut in the radial direction, and FIG. 3 is an enlarged view of a main part of FIG. FIG. 4 is an enlarged perspective view of a main part of the battery module of the first embodiment. Hereinafter, in the examples, the axial direction, the radial direction, and the circumferential direction mean the axial direction, the radial direction, and the circumferential direction with respect to the rotation axis L shown in FIG.

As shown in FIG. 1, the battery module of the first embodiment includes a case 1 and a plurality of battery cells 8.

The case 1 has a bottomed substantially cylindrical shape having two end walls 2, a peripheral wall 3, and an internal duct portion 4. The two end walls 2 form a disk having substantially the same shape, and are arranged coaxially with each other while being separated in the rotation axis L direction. The peripheral wall 3 extends in the circumferential direction while being integrated with the outer periphery of the two end walls 2, and forms a substantially cylindrical shape as a whole. The case 1 in the battery module of the first embodiment rotates counterclockwise as indicated by the white arrow in FIG. Hereinafter, in the first embodiment, the counterclockwise direction is referred to as a rotation direction of the case 1, if necessary.

A substantially circular end wall vent 20 is provided at the center of each end wall 2. An internal duct portion 4 is integrated with the end wall vent 20. The internal duct portion 4 has a substantially cylindrical shape having a plurality of slit-shaped duct openings 40. More specifically, the internal duct portion 4 communicates the end wall vents 20 of the two end walls 2 while aligning its central axis with the rotation axis L of the case 1. Each duct opening 40 is provided on the peripheral wall of the internal duct portion 4 and communicates with the inside and outside of the internal duct portion 4. The duct openings 40 are provided at predetermined intervals in the circumferential direction of the internal duct portion 4.

It can be said that the internal duct portion 4 extends in the axial direction inside the case 1. Since the internal duct portion 4 and the peripheral wall 3 are arranged coaxially, it can be said that the case 1 in the battery module of the first embodiment has a double tubular shape.

As shown in FIGS. 1 to 4, the peripheral wall 3 of the case 1 is provided with a plurality of peripheral wall vents 30 and a cover wall 35 that communicate the inside and outside of the case 1. The peripheral wall vents 30 are formed through the peripheral wall 3 and are arranged at predetermined intervals in the circumferential direction and the axial direction of the peripheral wall 3. The case 1 in the battery module of the first embodiment has a total of 12 peripheral wall vents 30. Six of the twelve peripheral wall vents 30 are referred to as first peripheral wall vents 31, and the remaining six are referred to as second peripheral wall vents 32. The first peripheral wall vents 31 are arranged at the same positions in the axial direction of the case 1 and at equal intervals in the circumferential direction of the case 1. The second peripheral wall vents 32 are arranged at different positions in the axial direction of the case 1 with respect to the first peripheral wall vents 31. The second peripheral wall vents 32 are arranged at the same positions in the axial direction of the case 1 and at equal intervals in the circumferential direction of the case 1. The first peripheral wall vent 31 and the second peripheral wall vent 32 are arranged at different positions in the circumferential direction of the case 1.

Each peripheral wall vent 30 has a rectangular shape curved along the peripheral wall 3 of the case 1. The length of each peripheral wall vent 30 in the circumferential direction of the case 1 is longer than the length of each peripheral wall vent 30 in the axial direction of the case 1. Each peripheral wall vent 30 extends in the circumferential direction of the case 1 and faces in the radial direction because it is formed on the peripheral wall 3. Each peripheral wall vent 30 is covered with a cover wall 35.

More specifically, as shown in FIG. 4, each cover wall 35 is composed of a cover peripheral wall 36 and two cover standing walls 37, and covers the corresponding peripheral wall vents 30 from the radial outside of the case 1. The cover peripheral wall 36 faces the peripheral wall vent 30. The two cover standing walls 37 are axially separated and opposed to each other. Each of the cover vertical walls 37 connects the axial end portion of the cover peripheral wall 36 and the peripheral wall 3 of the case 1.

As shown in FIG. 3, the radial distance between the cover peripheral wall 36 and the peripheral wall 3 of the case 1 gradually increases from one end to the other end of the cover peripheral wall 36 in the circumferential direction. In other words, the radial distance between the cover peripheral wall 36 and the peripheral wall 3 of the case 1 gradually increases in the circumferential direction of the peripheral wall 3, or the protruding height of each cover wall 35 from the peripheral wall 3 is the circumferential direction. It can be said that it is gradually increasing in.

One end of the cover peripheral wall 36 in the circumferential direction described above is referred to as a first cover end 36a. Further, the other end of the cover peripheral wall 36 in the circumferential direction described above is referred to as a second cover end 36b.

In the battery module of the first embodiment, the first cover end portion 36a of the cover peripheral wall 36 described above can be said to be the rear side of the cover peripheral wall 36 in the rotation direction. Further, the second cover end portion 36b of the cover peripheral wall 36 described above can be said to be the front side of the cover peripheral wall 36 in the rotation direction. Therefore, it can be said that the radial distance between the cover peripheral wall 36 and the peripheral wall 3 of the case 1 gradually increases from the rear side to the front side in the rotation direction of the case 1.

In other words, the radial distance between each cover peripheral wall 36 and the peripheral wall 3 of the case 1, or the protruding height of each cover wall 35 in the radial direction is from the rear side to the front side in the rotational direction of the case 1. It can be said that it is gradually increasing.

The first cover end portion 36a is integrated with the peripheral wall 3 of the case 1, and the second cover end portion 36b is radially separated from the peripheral wall 3 of the case 1. Therefore, it can be said that the cover wall 35 opens on the side of the second cover end portion 36b, and the inside and the outside of the cover wall 35 communicate with each other by the opening. The opening is referred to as a cover opening 38. The cover opening 38 is provided on the front side of the cover wall 35 in the rotational direction and faces the circumferential direction of the case 1. As shown in FIG. 3, the cover opening 38 is located at substantially the same position as one end of the peripheral wall vent 30 in the circumferential direction, that is, the front end of the peripheral wall vent 30 in the rotational direction of the case 1.

The space from the cover opening 38 to the peripheral wall vent 30 is partitioned by the cover wall 35 and the peripheral wall 3. The space is referred to as a cover-side air flow path 33.

As shown in FIG. 2, the case 1 is hollow, and a battery accommodating space 10 is provided inside the case 1. Each battery cell 8 is fixed inside the case 1 by a fixing member (not shown) and rotates together with the case 1. Inside the case 1, a battery module component (not shown) such as a bus bar is housed together with the battery cell 8. Similar to the battery cell 8, these battery module components are also fixed inside the case 1 and rotate together with the case 1. Each battery module component in the battery module of the first embodiment is appropriately positioned so as not to block the air flow path from the peripheral wall vent 30 to the battery cell 8. The battery module component may be provided with a vent (not shown) that is a part of the air flow path from the peripheral wall vent 30 to the battery cell 8.

A rotation drive mechanism (not shown) is connected to the case 1. The rotation drive mechanism causes the case 1 to rotate counterclockwise as shown by the white arrows in the figure. A cover wall 35 is projected from the outside of the case 1, and the cover wall 35 rotates together with the case 1. On the other hand, the air outside the case 1 is in a stopped state relative to the rotating case 1. Therefore, as shown by arrows in FIGS. 2 and 3, the air outside the case 1 is introduced into the air flow path 33 on the cover side through the cover opening 38, and is inside the case 1 through the peripheral wall vent 30, that is, the battery accommodating space. It flows into 10. As shown in FIG. 2, since the battery cell 8 is accommodated in the battery accommodating space 10, the air that has entered the battery accommodating space 10 exchanges heat with the battery cell 8 when passing in the vicinity of the battery cell 8. .. After that, the air flows into the internal duct portion 4 through the duct opening 40, and is discharged to the outside of the case 1 through the end wall vent 20.

According to the battery module of the first embodiment, the rotation of the case 1 itself introduces air from the outside of the case 1 toward the inside of the case 1. Then, the air inside the case 1 is pushed out to the outside of the case 1 by the pressure of the air directed from the outside of the case 1 to the inside of the case 1. That is, while the case 1 is rotating, air continuously flows from the outside to the inside of the case 1. Therefore, the battery module of the first embodiment does not require an air introduction device such as a blower fan, and can exchange heat between the air and the battery cell 8. For example, the battery cell 8 that generates heat when the battery cell 8 is discharged or charged is cooled by exchanging heat with cold air. Alternatively, when the battery module is placed in a cold environment without charging or discharging the battery cell 8, the battery cell 8 is cooled to a temperature at which it is difficult to suitably charge and discharge the battery cell 8. In this case, the battery cell 8 can be heated to a temperature suitable for charging and discharging by introducing warm air into the case 1 and exchanging heat between the warm air and the battery cell 8.

As described above, according to the battery module of the first embodiment, the temperature of the battery cell 8 can be set to a temperature suitable for charging and discharging in order to efficiently exchange heat between the air and the battery cell 8.

In the battery module of the first embodiment, as described above, the peripheral wall vents 30 are arranged at predetermined intervals in the circumferential direction and the axial direction of the peripheral wall 3. Therefore, the air introduced from the outside of the case 1 is evenly supplied to the inside of the case 1 in the circumferential direction and the axial direction. Therefore, according to the battery module of the first embodiment, heat exchange between the air and the battery cell 8 can be performed more efficiently.

Further, by arranging the peripheral wall vents 30 at predetermined intervals in the circumferential direction and the axial direction of the peripheral wall 3, the cover wall 35 provided corresponding to the peripheral wall vent 30 is also provided in the circumferential direction and the peripheral direction of the peripheral wall 3. They are arranged at predetermined intervals in the axial direction. By doing so, as shown by an arrow in FIG. 4, the air located in the vicinity of the peripheral wall 3 outside the case 1 is sewn between the adjacent cover walls 35 and flows relative to the case 1. obtain. Therefore, the retention of air outside the case 1 is suppressed, and a large amount of air can be introduced from the outside to the inside of the case 1 through the cover opening 38, the cover side air flow path 33, and the peripheral wall vent 30. In particular, since there is no other cover wall 35 and only the peripheral wall 3 on the front side of the cover opening 38 in the rotation direction of the case 1, the inflow of air into the cover opening 38 is not blocked, so that the air flows into the cover opening 38 from the outside. A lot of air can be introduced inside. Also by this, the battery module of the first embodiment can efficiently exchange heat between the air and the battery cell 8.

Further, in the battery module of the first embodiment, as shown by an arrow in FIG. 2, the air outside the case 1 is collected from the peripheral wall vent 30 toward the rotation axis L side of the case 1 and is coaxial with the rotation axis L. It is discharged from the end wall vent 20 through the internal duct portion 4 provided in the. That is, in the battery module of the first embodiment, the air flowing inside and outside the case 1 first flows in the circumferential direction and the radial direction of the case 1, then flows in the axial direction of the case 1 and is discharged to the outside of the case 1. It takes a very simple route.

For example, in the conventional battery pack introduced in Patent Document 1 described above, an air inlet and an outlet are provided at the axial ends of the air, and a blower fan is provided inside the case 1. Due to the arrangement, the path of the air circulating inside and outside the case 1 is very complicated. If the path of the air flowing inside and outside the case 1 is complicated, it may be difficult to efficiently exchange air between the inside and outside of the case 1, and it may be difficult to efficiently exchange heat between the air and the battery cell 8. is there.

On the other hand, in the battery module of the first embodiment, since the air path flowing inside and outside the case 1 is very simple, the air can be efficiently exchanged between the inside and the outside of the case 1. As a result, heat exchange between the air and the battery cell 8 can be efficiently performed.

Further, in the battery module of the first embodiment, the air circulating inside and outside the case 1 also flows in the radial direction of the case 1. Therefore, according to the battery module of the first embodiment, the inside of the case 1 is directed from the outer circumference to the center. It can be said that the air is evenly supplied in the radial direction. This also allows efficient heat exchange between the air and the battery cell 8.

For example, when the rotation direction of the case 1 in the battery module of the first embodiment is the opposite direction, that is, the clockwise direction in FIG. 2, the air from the outside to the inside of the case 1 passes through the cover opening 38 and the peripheral wall vent 30. Flow stops. However, in this case, as the case 1 rotates clockwise, the flow velocity between the air near the peripheral wall 3 outside the case 1 and the air near the peripheral wall vent 30 inside the case 1 There is a difference. Therefore, the region near the peripheral wall 3 outside the case 1 has a negative pressure as compared with the region near the peripheral wall vent 30 inside the case 1. Therefore, the air inside the case 1 flows out to the outside of the case 1 through the peripheral wall vent 30, the cover side air flow path 33, and the cover opening 38. Then, the air pressure inside the case 1 drops, and the air outside the case 1 is introduced into the case 1 through the end wall vent 20. Therefore, in this case, air is introduced from the outside to the inside of the case 1 through the end wall vent 20, the internal duct portion 4, and the duct opening 40. The air introduced into the case 1 exchanges heat with the battery cell 8 inside the case 1, and is discharged to the outside of the case 1 through the peripheral wall vent 30 and the cover opening 38. Therefore, also in this case, air is exchanged inside and outside the case 1, and heat exchange between the air and the battery cell 8 is performed.

In the battery module of the first embodiment, if a rotation drive mechanism capable of rotationally driving the case 1 in two directions, counterclockwise and clockwise, is used, the rotation direction of the case 1 can be switched as needed. For example, when a rotary drive mechanism capable of rotationally driving the case 1 in two directions is used and the internal duct portion 4 is connected to a heat source (not shown), the case 1 is rotated clockwise to the inside of the case 1. It is also possible to introduce cold air into the case 1 by introducing warm air and rotating the case 1 counterclockwise. That is, in this case, the temperature of the air introduced into the case 1 can be selected from two types, low temperature and high temperature. Therefore, in this case, there is an advantage that the temperature inside the case 1 can be controlled more precisely and the temperature of the battery cell 8 can be made more suitable for the battery reaction.

(Example 2)
FIG. 5 is an enlarged perspective view of a main part at the same position as FIG. 4 of the battery module of the second embodiment.

The battery module of the second embodiment is substantially the same as the battery module of the first embodiment except that the case 1 has the guide rib 15.

The case 1 in the battery module of the second embodiment has a plurality of guide ribs 15. One end portion 15a of each guide rib 15 rises from the outer surface of the end wall 2 of the case 1 in the axial direction of the case 1. The other end 15b of each guide rib 15 extends to the peripheral wall 3 of the case 1 and extends in the vicinity of the cover opening 38.

Therefore, in the case 1 of the battery module of the second embodiment, not only the air in the vicinity of the peripheral wall 3 but also the air in the vicinity of the end wall 2 can be introduced into the case 1. Therefore, according to the battery module of the second embodiment, heat exchange between the air and the battery cell 8 can be performed more efficiently.

(Example 3)
FIG. 6 is an enlarged cross-sectional view of a main part of the battery module of the third embodiment at the same position as that of FIG.

The battery module of the third embodiment is substantially the same as the battery module of the first embodiment except for the shape of the peripheral wall 3 in the vicinity of the peripheral wall vent 30. Hereinafter, the battery module of the third embodiment will be described by focusing on the shape of the peripheral wall 3 in the vicinity of the peripheral wall vent 30.

As shown in FIG. 6, the peripheral wall 3 in the battery module of the third embodiment is curved in the radial direction in the vicinity of the peripheral wall vent 30. Specifically, the peripheral edge of the peripheral wall vent 30 of the peripheral wall 3 extends radially inward in a tubular shape. The tubular portion is referred to as an air guide portion 34. Among the air guide portions 34, the front side portion 34f located on the front side (cover opening 38 side) of the case 1 in the rotational direction with respect to the peripheral wall vent 30 is curved toward the inside of the case 1.

Similar to the battery module of the first embodiment, the battery module of the third embodiment is formed from the outside to the inside of the case 1 through the cover opening 38, the air flow path 33 on the cover side, and the peripheral wall vent 30 by rotating the case 1. Air is introduced into. As described above, in the battery module of the third embodiment, the peripheral edge portion of the peripheral wall vent 30, that is, the air guide portion 34 extends in a tubular shape toward the inside in the radial direction of the case 1, and therefore passes through the cover opening 38. The air that has reached the air flow path 33 on the cover side is guided by the air guide portion 34 and smoothly introduced into the inside of the case 1. In particular, since the front side portion 34f near the cover opening 38 is gently curved toward the inside of the case 1, the generation of turbulent flow is suppressed and the air flow inside the case 1 is adjusted.

Therefore, according to the battery module of the third embodiment, heat exchange between the air and the battery cell 8 can be performed more efficiently.

The tip portion 34f of the air guide portion 34 may be curved, and the curvature may be large or small.

When the curvature of the tip portion 34f in the air guide portion 34 is large, for example, when the tip portion 34f is sharply curved and the extension line of the tip portion 34f faces the rotation center of the case 1, the inside and outside of the case 1. There is an advantage that air can be exchanged efficiently. On the other hand, when the curvature of the tip portion 34f in the air guide portion 34 is small, for example, when the tip portion 34f is gently curved and the extension line of the tip portion 34f faces the peripheral wall 3 of the case 1, the case 1 There is an advantage that air can be slowly introduced into the case and turbulence inside the case 1 can be suppressed.

In the third embodiment, the air guide portion 34 has a tubular shape, but the shape of the air guide portion 34 is not limited to this. For example, the air guide portion 34 may be formed only by the front side portion 34f that is gently curved toward the inside of the case 1.

(Example 4)
FIG. 7 is an enlarged cross-sectional view of a main part of the battery module of the fourth embodiment at the same position as that of FIG.

The battery module of the fourth embodiment is substantially the same as the battery module of the first embodiment except for the shape of the peripheral wall vent 30 and the shape of the cover wall 35. Hereinafter, the battery module of the fourth embodiment will be described with a focus on the shape of the peripheral wall vent 30 and the shape of the cover wall 35.

The opening area of the peripheral wall vent 30 in the battery module of the fourth embodiment is smaller than the opening area of the cover opening 38. Therefore, the flow path cross-sectional area of the cover-side air flow path 33 gradually decreases from the cover opening 38 toward the peripheral wall vent 30. In other words, in the case 1 of the battery module of the fourth embodiment, the flow path cross-sectional area of the cover-side air flow path 33 is narrowed toward the peripheral wall vent 30. Therefore, in the battery module of the fourth embodiment, the flow velocity of the air in the cover-side air flow path 33 becomes higher at the peripheral wall vent 30. By doing so, the negative pressure in the air flow path 33 on the cover side increases, and the amount of air introduced from the outside to the inside of the case 1 through the cover opening 38 increases. Therefore, according to the battery module of the fourth embodiment, heat exchange between the air and the battery cell 8 can be performed more efficiently.

(Example 5)
FIG. 8 is an enlarged cross-sectional view of a main part of the battery module of the fifth embodiment at the same position as that of FIG.

The battery module of the fifth embodiment does not have the cover wall 35, and the shape of the peripheral wall 3 in the vicinity of the peripheral wall vent 30 is also different from that of the battery module of the first embodiment. Further, the battery module of the fifth embodiment rotates in the direction opposite to that of the battery module of the first embodiment. Other than that, the battery module of the fifth embodiment is substantially the same as the battery module of the first embodiment. Hereinafter, the battery module of the fifth embodiment will be described by focusing on the shape of the peripheral wall 3 in the vicinity of the peripheral wall vent 30.

Case 1 in the battery module of Example 5 does not have a cover wall 35. Therefore, in the battery module of the fifth embodiment, the peripheral wall vent 30 provided on the peripheral wall 3 of the case 1 is exposed. The portion of the peripheral wall 3 located on the rear side of the peripheral wall vent 30 in the rotational direction is gently curved toward the inside of the case 1 to form the air guide portion 34.

As described above, the battery module of the fifth embodiment rotates in the direction opposite to that of the battery module of the first embodiment. Therefore, unlike the battery modules of Examples 1 to 4, the inflow of air from the outside to the inside of the case 1 through the peripheral wall vent 30 does not occur. Instead, when the case 1 rotates, a flow velocity difference occurs between the air in the vicinity of the peripheral wall 3 outside the case 1 and the air in the vicinity of the peripheral wall vent 30 inside the case 1, and the case 1 has a flow velocity difference. The external side becomes negative pressure. Therefore, the air inside the case 1 flows out to the outside of the case 1 through the air guide portion 34 and the peripheral wall vent 30, and although not shown in FIG. 8, the air outside the case 1 passes through the end wall vent 20. After that, it is introduced inside the case 1. That is, in the battery module of the fifth embodiment, air is introduced from the outside to the inside of the case 1 through the end wall vent 20, the internal duct portion 4, and the duct opening 40. The air introduced into the case 1 exchanges heat with the battery cell 8 inside the case 1, and is discharged to the outside of the case 1 through the air guide portion 34 and the peripheral wall vent 30.

Therefore, also in the battery module of the fifth embodiment, heat exchange between the air and the battery cell 8 can be efficiently performed, and the temperature inside the case 1 can be set to a temperature suitable for using the battery cell 8.

In the battery module of the fifth embodiment, the air outside the case 1 is introduced into the case 1 through the end wall vent 20 and the internal duct portion 4, and circulates inside the case 1 toward the peripheral wall 3. Then, it is discharged from the peripheral wall vent 30. That is, in the battery module of the fifth embodiment, the air circulating inside and outside the case 1 first flows in the axial direction of the case 1, then flows in the radial direction of the case 1 and is discharged to the outside of the case 1. Take a very simple route. Therefore, even in the battery module of the fifth embodiment, the air flow path is very simple, the air can be efficiently exchanged between the inside and the outside of the case 1, and by extension, the air and the battery cell 8 are exchanged with each other. Heat exchange can be performed efficiently.

(Example 6)
FIG. 9 is an enlarged cross-sectional view of a main part of the battery module of the sixth embodiment at the same position as that of FIG. Further, FIG. 10 is an explanatory diagram schematically showing a state in which the battery module of the sixth embodiment is viewed from the axial direction.

The battery module of the sixth embodiment is substantially the same as the battery module of the first embodiment except for the shape of the cover wall 35. Hereinafter, the battery module of the sixth embodiment will be described with a focus on the shape of the cover wall 35.

The cover wall 35 in the battery module of the sixth embodiment is a separate body from the peripheral wall 3, and has a plate shape substantially the same shape as the peripheral wall vent 30. The cover wall 35 covers the peripheral wall vent 30 and is pivotally supported by the peripheral wall 3 at a position rearward of the peripheral wall vent 30 in the rotational direction of the case 1. Therefore, the cover wall 35 can swing with respect to the peripheral wall 3. An urging member 39 is attached to the shaft 35s of the cover wall 35. In the battery module of the sixth embodiment, a torsion spring is used as the urging member 39. One end of the torsion spring is fixed to the peripheral wall 3, and the other end is fixed to the cover wall 35. Then, the urging member 39 urges the cover wall 35 in the direction of closing the peripheral wall vent 30 with the axis 35s of the cover wall 35 as the center. More specifically, the urging member 39 urges the cover wall 35 and rotates it counterclockwise in FIGS. 9 and 10.

The case 1 in the battery module of the sixth embodiment rotates counterclockwise. When the case 1 is rotated, the centrifugal force acting on the cover wall 35 exceeds the urging force of the urging member 39, and the cover wall 35 rotates clockwise around the shaft 35s to open the peripheral wall vent 30. Then, the air outside the case 1 hits the inner surface of the cover wall 35 and is introduced into the inside of the case 1 through the peripheral wall vent 30. The air introduced into the case 1 is discharged to the outside of the case 1 through the end wall vent 20 as in the battery module of the first embodiment. Therefore, also in the battery module of the sixth embodiment, the air can be efficiently exchanged between the outside and the inside of the case 1, and the heat exchange between the air and the battery cell 8 can be efficiently performed.

Further, in the battery module of the sixth embodiment, the cover wall 35 opens and closes the peripheral wall vent 30. The cover wall 35 is closed by the urging force of the urging member 39 when the case 1 is not rotating. Therefore, when the battery module is not used, if the peripheral wall vent 30 is closed by the cover wall 35, the case 1 can be miniaturized as a whole, and the space for arranging the case 1 can be reduced. Further, by closing the peripheral wall vent 30 by the cover wall 35, it is possible to suppress the invasion of foreign matter into the inside of the case 1 and the temperature change inside the case 1. Therefore, it can be said that the battery module of the sixth embodiment is suitable for outdoor use and storage.

(Example 7)
The battery module of the seventh embodiment is substantially the same as the battery module of the sixth embodiment except that the urging member 39 made of a shape memory alloy is provided instead of the urging member 39 made of a torsion spring. Hereinafter, the battery module of the seventh embodiment will be described with reference to FIG. 10 regarding the battery module of the sixth embodiment and focusing on the urging member 39.

The cover wall 35 in the battery module of the seventh embodiment is separate from the peripheral wall 3 and is pivotally supported by the peripheral wall 3. Therefore, the cover wall 35 in the battery module of the seventh embodiment can also swing with respect to the peripheral wall 3. An urging member 39 made of a shape memory alloy is integrated with the shaft 35s of the cover wall 35. The urging member 39 urges the cover wall 35 in the direction of closing the peripheral wall vent 30 at low temperatures, deforms when the temperature inside the case 1 rises, and covers the cover wall 35 in the direction of opening the peripheral wall vent 30. To urge.

Therefore, according to the battery module of the seventh embodiment, when the battery cell 8 generates heat during charging or discharging, the temperature inside the case 1 rises and the cover wall 35 opens the peripheral wall vent 30. Therefore, air is introduced from the outside to the inside of the case 1, exchanges heat with the introduced air, and the battery cell 8 is cooled. The battery module of the seventh embodiment has an advantage that the temperature of the battery cell 8 can be automatically controlled because the cover wall 35 automatically opens and closes according to the temperature change. Further, when the temperature inside the case 1 drops, the cover wall 35 automatically closes the peripheral wall vent 30 by the function of the urging member 39, so that the temperature of the air inside the case 1 changes to the battery reaction of the battery cell 8. It is kept at a suitable temperature. Therefore, according to the battery module of the seventh embodiment, the battery cell 8 can be automatically maintained at a temperature suitable for the battery reaction, and the battery performance of the battery cell 8 can be fully exhibited.

(Example 8)
FIG. 11 is a perspective view schematically showing the battery module of the eighth embodiment. FIG. 12 is an enlarged cross-sectional view of a main part schematically showing a state in which the case of the battery module of the eighth embodiment is cut along the axial direction.

The battery module of the eighth embodiment does not have the end wall vent 20 and the internal duct portion 4, the orientation of some of the cover walls 35 is different from the orientation of the other cover walls 35, and the case 1. It differs from the battery module of the first embodiment in that there is a partition wall 11 that divides the inside into two in the axial direction of the case 1. Other than that, the battery module of the eighth embodiment is substantially the same as the battery module of the first embodiment. Hereinafter, the battery module of the eighth embodiment will be described with a focus on the case 1.

The battery module of Example 8 has two types of cover walls 35. One is a cover wall 35 having a cover opening 38 facing the front side in the rotation direction of the case 1, similar to the battery module of the first embodiment. The cover wall 35 is referred to as a first cover wall 41, and the cover opening 38 is referred to as a first cover opening 45. The other of the two types of cover walls 35 is a cover wall 35 having a cover opening 38 directed to the rear side in the rotation direction of the case 1. The cover wall 35 is referred to as a second cover wall 42, and the cover opening 38 is referred to as a second cover opening 46.

The battery module of the eighth embodiment has a plurality of first cover walls 41 and a plurality of second cover walls 42, respectively. Each first cover wall 41 covers the first peripheral wall vent 31, and each second cover wall 42 covers the second peripheral wall vent 32. Therefore, the first cover wall 41 and the second cover wall 42 are separated from each other in the axial direction of the case 1.

As shown in FIG. 12, the case 1 is further provided with a partition wall 11 that divides the battery storage space 10 inside the case 1 into two in the axial direction. One of the two spaces partitioned by the partition wall 11 is referred to as a first accommodation space 10a, and the other is referred to as a second accommodation space 10b. The first accommodating space 10a communicates with the first peripheral wall vent 31, and the second accommodating space 10b communicates with the second peripheral wall vent 32. The partition wall 11 has a number of openings 12 through which the battery cell 8 can be inserted, corresponding to the battery cell 8. Therefore, the battery cells 8 shown by the alternate long and short dash lines in FIG. 12 are arranged in the battery accommodating space 10 in the same manner as the battery module of the first embodiment, and the first accommodating space 10a and the second accommodating space are arranged through the opening 12 of the partition wall 11. Exposed to both with 10b. A connecting opening 13 for connecting the first accommodating space 10a and the second accommodating space 10b is further provided in a portion of the partition wall 11 in the vicinity of the rotation axis L, that is, a central portion of the partition wall 11.

When the case 1 is rotated counterclockwise as shown in FIG. 11, the air outside the case 1 passes through the first cover opening 45 of the first cover wall 41 and the first peripheral wall vent 31, and the inside of the case 1 is concrete. Is introduced into the first accommodation space 10a. The air introduced into the first accommodation space 10a exchanges heat with the battery cell 8 while flowing from the outer peripheral side of the case 1 toward the center, and flows axially through the communication opening 13 into the second accommodation space 10b. Moving. Then, in the second accommodation space 10b, heat is exchanged with the battery cell 8 while flowing from the central portion toward the outer peripheral side, and the case 1 is passed through the second cover opening 46 of the second peripheral wall vent 32 and the second cover wall 42. It is discharged to the outside.
Therefore, also in the battery module of the eighth embodiment, the temperature of the battery cell 8 can be set to a temperature suitable for charging and discharging in order to efficiently exchange heat between the air and the battery cell 8.

Therefore, also in the battery module of the eighth embodiment, the temperature of the battery cell 8 can be set to a temperature suitable for charging and discharging in order to efficiently exchange heat between the air and the battery cell 8.

Further, also in the battery module of the eighth embodiment, the flow path of the air flowing inside and outside the case 1 is very simple. Therefore, also in the battery module of the eighth embodiment, the air can be efficiently exchanged between the inside and the outside of the case 1, and the heat exchange between the air and the battery cell 8 can be efficiently performed.

The case 1 of the battery module of the eighth embodiment may be provided with a guide portion that guides the air flow direction in the radial direction. For example, a guide rib that rises in the axial direction of the case 1 and extends from the outer peripheral side of the end wall 2 toward the rotation axis L side may be provided on the inner surface of the end wall 2. Alternatively, similarly to the air guide portion 34 shown in FIG. 6, a tubular air guide portion extending inward in the radial direction of the case 1 may be provided on the peripheral wall 3. By providing such a guide portion in the case 1, the flow direction of the air inside the case 1 can be directed not only in the spiral direction described above but also in the radial direction of the case 1, and the air and the battery cell 8 can be brought into contact with each other. Heat exchange can be performed more efficiently.

The application of the battery module of the present invention is not particularly limited, and the battery module can be arranged in various devices, equipment, and the like. As a specific example, an assembled battery mounted on a vehicle can be mentioned.

The present invention is not limited to the embodiment described above and shown in the drawings, and can be appropriately modified and implemented without departing from the gist. In addition, each component shown in the embodiment can be arbitrarily extracted and combined.

The battery module of the present invention can be expressed as follows.
(1) A battery cell 8 and a case 1 for accommodating and holding the battery cell 8 inside are provided.
The case 1 can rotate about the rotation axis L, and can rotate around the rotation axis L.
The case 1 has two end walls 2 forming both end faces in the rotation axis direction and a peripheral wall 3 forming an outer peripheral surface.
The peripheral wall 3 is a battery module having a peripheral wall vent 30 that communicates the inside and outside of the case 1.
(2) The battery module according to (1), wherein at least one of the two end walls 2 has an end wall vent 20 that communicates the inside and outside of the case 1.
(3) The case 1 has a cover wall 35 that covers the peripheral wall vent 30 from the outside in the radial direction.
The cover wall 35 has a cover opening 38 facing the circumferential direction of the case 1, and together with the peripheral wall 3, partitions a cover-side air flow path 33 from the cover opening 38 to the peripheral wall vent 30 (1). Or the battery module according to (2).
(4) The battery module according to (3), wherein the radial distance between the peripheral wall 3 and the cover wall 35 gradually increases in the circumferential direction of the peripheral wall 3.
(5) The battery module according to (3), wherein the cover wall 35 is swingably supported by the peripheral wall 3 and the peripheral wall vent 30 can be opened and closed.
(6) Having a plurality of peripheral wall vents 30
The battery module according to any one of (1) to (5), wherein the peripheral wall vents 30 are arranged apart from each other in the circumferential direction of the case 1.

1: Case 2: End wall 20: End wall vent 3: Peripheral wall 30: Peripheral wall vent 33: Cover side air flow path 35: Cover wall 38: Cover opening 8: Battery cell L: Rotating shaft

Claims (5)

A battery cell and a case for accommodating and holding the battery cell inside are provided.
The case is rotated about an axis of rotation,
The case has two end walls forming both end faces in the rotation axis direction, a peripheral wall forming an outer peripheral surface of the case and having a peripheral wall vent that communicates with the inside and outside of the case, and the peripheral wall vent that communicates with the peripheral wall vent. It has a guide passage for introducing air outside the case into the case.
The guide passage is a battery module having a cover opening that is radially outside the peripheral wall and faces in the same direction as the rotation direction. A battery cell and a case for accommodating and holding the battery cell inside are provided.
The case is rotated about an axis of rotation,
The case has two end walls forming both end faces in the rotation axis direction, a peripheral wall forming an outer peripheral surface of the case and having a peripheral wall vent that communicates with the inside and outside of the case, and the peripheral wall vent that communicates with the peripheral wall vent. It has a guide passage for discharging the air inside the case to the outside of the case.
A battery module in which the guide passage is radially inside the peripheral wall and has a cover opening facing in the same direction as the rotation direction. The battery module according to claim 1, wherein the guide passage is swingably supported by the peripheral wall and is partitioned by a cover wall capable of opening and closing the peripheral wall vent. The battery module according to any one of claims 1 to 3 , wherein at least one of the two end walls has an end wall vent that communicates the inside and outside of the case. It has a plurality of pairs of the peripheral wall vent and the guide passage connecting to the peripheral wall vent.
The battery module according to any one of claims 1 to 4 , wherein the peripheral wall vent and the guide passage are arranged apart from each other in the circumferential direction of the case.

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