JP2007172983A - Battery pack - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a battery pack capable of being shortened and downsized, and uniformly cooling a whole battery module. <P>SOLUTION: The battery pack is provided with a battery module 10 structured by laminating a plurality of cells in a case 2, an inner air intake duct supplying the battery module 10 with a coolant guided into the case 2 through a coolant guide-in port, and an inner drainage duct draining the coolant guided out of the battery module outside the case through the coolant drainage port. The coolant guide-in port and the coolant drainage port are fitted to the same side of the case 2, and the coolant guide-in port induces the coolant passing through it in a first direction, while, the inner air intake duct is provided with a rectifying means for deflecting the coolant guided out of an outlet of the inner air intake duct in a second direction practically crossing the first direction. Each cell is provided with a number of circulation paths 65 for a coolant to flow through between itself and the adjacent celled, sizes of the number of circulation paths are different at an upstream side and a downstream side of the second direction. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a battery pack mounted on an electric vehicle or the like.

  In recent years, an electric vehicle using an electric motor as a drive source and a so-called hybrid electric vehicle combining an electric motor and another drive source have been put into practical use. In such a vehicle, a battery for supplying electric energy to the electric motor is mounted. As this battery, for example, a secondary battery such as a nickel cadmium battery, a nickel hydride battery, or a lithium ion battery that can be repeatedly charged and discharged is used.

  Usually, the secondary battery is configured as a battery module in which battery cells are stacked, and is mounted on a vehicle or the like in a state where the battery module is accommodated in a casing. This casing, the battery module and other components housed in the casing are referred to as a battery pack.

  The battery module generates heat due to an internal electrochemical reaction, and its temperature rises. Since the power generation efficiency of the battery module decreases when the temperature rises, for example, cooling air or the like is introduced into the housing from the outside to cool the battery module.

  Various types of battery pack cooling structures using this cooling air have been proposed. For example, the battery module is accommodated in the housing in an inclined state in the longitudinal direction so that the refrigerant is uniformly supplied in the longitudinal direction of the battery module, and the cross-sectional area of the cooling air supply path to the battery cell is set upstream. A method has been proposed in which the pressure is lowered toward the downstream side (Patent Document 1).

In addition, the battery pack is required to have a low profile due to the mounting space when the battery pack is mounted on the vehicle. Therefore, normally, the intake fan and the exhaust fan of the battery pack are arranged so as to protrude from both side surfaces sandwiching the longitudinal direction of the battery module.
Japanese Unexamined Patent Publication No. 7-320794

  However, when the height of the battery pack is reduced by the above-described arrangement, the battery module intake fan and exhaust fan are arranged on the opposite side of the battery pack, so that the battery pack cannot be sufficiently downsized. There is a problem that it cannot be installed.

  As a countermeasure for this problem, it is conceivable to configure the cooling flow path of the battery pack so that the intake fan and the exhaust fan can be installed on the same side of the battery pack. It is necessary to deflect the flow of cooling air, and it is difficult to maintain a uniform flow of cooling air supplied to the battery module. Therefore, there exists a problem that temperature distribution arises in a battery module and favorable performance cannot be obtained.

  The present invention has been made in view of such problems, and it is possible to reduce the height and size of the battery pack and to provide a battery pack having a cooling structure capable of uniformly cooling the entire battery module. The issue is to provide.

In order to solve the above problems, in the present invention, a battery module configured by stacking a plurality of cells in a casing and a refrigerant introduced into the casing through a refrigerant inlet are supplied in the direction of the battery module. A battery pack, and an internal exhaust duct for discharging the refrigerant derived from the direction of the battery module to the outside of the housing through the refrigerant discharge port, wherein the refrigerant introduction port and the refrigerant discharge The outlet is installed on the same surface side of the housing, the refrigerant introduction port guides the refrigerant passing through the refrigerant introduction port in the first direction, and the internal intake duct is led out from the outlet port of the internal intake duct. And rectifying means for deflecting the refrigerant in a second direction substantially perpendicular to the first direction, and each cell has a number of flow passages through which the refrigerant flows between adjacent cells. ,
The number of the flow paths is different between the upstream side and the downstream side in the second direction, and / or the housing has an opening at a part of the position corresponding to the upper part of the battery module. A battery pack is provided.

  By defining the structure of the battery pack in this way, the battery pack can be reduced in height and size. Further, even if the flow of the refrigerant is deflected in the internal intake duct, turbulent flow or the like is hardly generated, and further, the refrigerant can be uniformly circulated through each flow passage of the refrigerant formed in the battery module.

Here, the rectifying means comprises a plurality of slits installed on the bottom surface of the internal intake duct, each of the plurality of slits having a respective opening at the outlet of the internal intake duct, It may be installed along the second direction so as to partition the bottom surface of the internal intake duct seamlessly. By configuring the shape of the rectifying means in this way, the above-described effects can be easily obtained. The multiple flow passages are selected from two types of dimensions, and have a large dimension on the upstream side in the second direction. And may be selected to have a small dimension downstream. As a result, the refrigerant easily flows through the multiple flow passages on the upstream side in the second direction, and the battery module can be cooled more uniformly.

  Alternatively, the dimensions of the multiple flow paths may be selected so as to gradually decrease from the upstream side to the downstream side in the second direction.

  The plurality of flow passages may be formed between the protrusions provided on at least one surface of the opposing surface facing each adjacent cell of each cell.

  The protrusion may be composed of a plurality of linear ribs installed in parallel along the height direction of the battery module. In this case, by changing the width and / or interval of the ribs, it is possible to easily change the width in the second direction of the multiple flow passages described above.

  The first direction may be a direction substantially parallel to the cell stacking direction. Thereby, it becomes possible to cool each laminated battery cell more uniformly.

  The opening is composed of a plurality of openings, and the position of the plurality of openings in the first direction is set at a position approximately corresponding to an upper portion of a gap formed between each cell and a cell adjacent to the cell. The position of the opening in the second direction is preferably set at a position approximately corresponding to the upper part of the region from the upstream side surface in the second direction of the battery module to the central portion in the same direction. By installing the opening in this manner, the above-described effects of the present invention can be expressed more effectively.

  Alternatively, the opening consists of a single opening, and the position of the single opening in the first direction roughly corresponds to the upper part of the region between the two side surfaces perpendicular to the first direction of the battery module. The position of the opening in the second direction is approximately the position corresponding to the upper part of the region from the upstream side surface in the second direction of the battery module to the central portion in the same direction. Also good.

  In the battery pack of the present invention, since the introduction part of the refrigerant into the housing and the exhaust part are installed on the same side surface of the housing, the battery pack can be reduced in height and size. Further, the refrigerant is provided in the battery module by the rectifying means provided in the internal air intake duct, and also by the openings provided at appropriate positions of the refrigerant flow passages and / or the housing appropriately arranged in the battery module. In addition, since it is possible to control so as to be supplied uniformly to a large number of refrigerant flow paths, the entire battery module can be uniformly cooled.

  Embodiments based on the present invention will be described below.

  FIG. 1 shows an example of a mounting state of a battery pack in a vehicle according to the present embodiment.

  In FIG. 1, the battery pack 1 is mounted on the rear side of the rear seat 500 of the vehicle. However, it should be noted that the mounting location of the battery pack 1 is not particularly limited. As the refrigerant introduced into the battery pack 1, for example, cooling air by air in the vehicle compartment is used. The same side surface of the battery pack 1 includes an external intake duct 80 for guiding the air in the vehicle interior to the battery pack 1 and an external exhaust duct 90 for exhausting the cooling air introduced into the battery pack 1 to the outside. It is connected to.

  FIG. 2 is a block diagram when the vehicle 100 is driven by a battery system having a battery pack according to the present invention. The vehicle 100 includes a control unit 101, a battery unit 102 including a battery pack, and a drive unit 103. The control unit 101 is installed in a device box 30 (see FIG. 3) arranged inside the battery pack 1, and controls the battery 102 and the drive unit 103. The drive unit 103 may include an internal combustion engine such as a gasoline engine or a diesel engine in addition to an electric motor such as a motor driven by a current supplied from the battery unit 102. That is, the vehicle 100 includes not only an electric vehicle but also a hybrid car provided with a driving means other than an electric motor such as a gasoline engine.

  FIG. 3 is a perspective view of the battery pack of the present invention, and FIG. 4 is a schematic cross-sectional view taken along the line III-III of the battery pack shown in FIG. Note that the cooling structure of the battery pack 1 of this embodiment is a so-called upflow type in which the refrigerant flows from the bottom to the top in the battery module. In each figure, the white arrow indicates the flow of the refrigerant. In the following description, the case where this refrigerant is cooling air will be described as an example. However, it will be apparent to those skilled in the art that the refrigerant is not limited to this in the present invention.

  As shown in FIG. 3 and FIG. 4, the battery pack 1 includes a housing 2 composed of an upper case 3 and a lower case 4, a battery module 10 disposed inside the housing 2, an internal intake duct 8, and an internal An exhaust duct 9 and an equipment box 30 are provided.

  The housing 2 is configured by combining the upper case 3 and the lower case 4 and fastening the ends with bolts 33, and has a space inside.

  The battery module 10 is configured by stacking a plurality of battery cells 11 as shown in FIG. As the battery cell, for example, a secondary battery such as a nickel cadmium battery, a nickel hydrogen battery, or a lithium ion battery can be used. The battery cell 11 has a so-called square plate-like outer shape.

  Projections 11a are provided on the side surfaces of the individual battery cells 11 (both ends in the Y direction in FIG. 4), and the projections 11a extend to the side surfaces of the battery module 10 after the battery cells 11 are stacked. Parts. End plates 15 that maintain the stacked state of the battery modules 10 are disposed at both ends in the stacking direction (X direction) of the battery modules 10 (see FIG. 5). They are connected by a blanket 26 and a restraining belt 16 (see FIG. 4) that engage with protrusions formed on the side surfaces.

  A plurality of protrusions (not shown in FIG. 4) projecting in the X direction, which will be described later, on at least one end surface perpendicular to the X direction of each battery cell 11 (hereinafter referred to as a main surface 11b of the battery cell 11) A part of a passage (hereinafter referred to as “cooling air flow passage 65”) through which the cooling air flows between the stacked battery cells 11 by these protrusions (to be precise, the space between the protrusions) is provided. (Not shown in FIG. 4). Details of the cooling airflow passage 65 will be described later. In the present embodiment, the battery module 10 is installed so as to have a predetermined angle of inclination with respect to the bottom surface of the lower case 4 (inclination in the Y direction in FIG. 4). This is because the cooling air discharged from the internal intake duct 8 is uniformly supplied to the lower surface side of the battery module 10.

  The internal space of the housing 2 is partitioned by the battery module 10. An upper space is formed between the upper surface of the battery module 10 and the upper case 3, and the upper cooling flow path 5 is shaped by this upper space. Further, a lower space is formed between the lower surface of the battery module 10 and the lower case 4, and the lower cooling flow path 6 is shaped by this lower space. Therefore, the cooling flow path is configured in the housing 2 by the space in which the upper cooling flow path 5, the lower cooling flow path 6 and the battery module 10 are installed (a large number of cooling airflow paths 65 formed by the protrusions described above). The Between one of the side end surfaces (side end surfaces orthogonal to the Y direction) of the battery module 10 parallel to the stacking (X) direction of the cells 11 and the side surfaces of the upper case 3 and the bottom case 4 facing this, the first Side space 7a is formed. Further, between the other of the side end faces (side end faces orthogonal to the Y direction) of the battery module 10 parallel to the stacking (X) direction of the cells 11 and the side surfaces of the upper case 3 and the bottom case 4 facing each other, Two side spaces 7b are formed.

  A gasket 23 is installed between the upper cooling flow path 5, the first side space 7a, and the second side space 7b, and airtightness between these spaces is ensured. Further, a gasket 23 is installed between the lower cooling flow path 6 and the first side space 7a and the second side space 7b, and the confidentiality between these spaces is ensured. For this gasket 23, for example, an independent foamed EPDM rubber or the like is used.

  An internal intake duct 8 and an internal exhaust duct 9 are installed in the first side space 7a and the second side space 7b located on the side surface side of the battery module 10, respectively. As shown in FIG. 3, an intake port 8a is provided on one surface of the housing so that the cooling air is supplied in the longitudinal direction (X direction) of the internal intake duct 8, and the internal intake duct 8 It communicates with the mouth 8a. Further, an exhaust port 9a is provided on the same housing surface as the surface on which the intake port 8a is provided so that the cooling air is discharged in the longitudinal direction (X direction) of the internal exhaust duct 9, and the internal exhaust duct 9 Communicates with the exhaust port 9a. The internal intake duct 8 corresponds to a communication portion that connects the intake port 8a corresponding to the cooling air introduction port and the lower cooling channel 6 that is a part of the cooling channel. Similarly, the internal exhaust duct 9 corresponds to a communication portion that connects the exhaust port 9a corresponding to the cooling air outlet and the upper cooling channel 5 that is a part of the cooling channel.

  As described above, according to the battery pack 1 of the present invention, the introduction portion of the cooling air to the housing and the exhaust portion are installed on the same side surface of the housing, so that the battery pack can be reduced in height and size. .

  However, in the battery pack cooling structure of the present invention, after the cooling air is introduced into the internal intake duct 8, it is necessary to deflect the cooling air toward the battery module 10 (more precisely, the lower cooling flow path 6). In general, the deflection of the cooling air causes turbulence and eddy currents. In such a situation where the turbulent flow or vortex of the cooling air is generated, the cooling air introduced from the internal intake duct 8 through the lower cooling flow path 6 is not uniformly supplied to the battery module 10 side, and is locally supplied to the battery module. Temperature rise may occur. Such a local temperature rise of the battery module may deteriorate the battery performance and impair the reliability of the battery.

  On the other hand, in the present invention, the first feature is that a rectifying means is provided in the internal intake duct 8 for the purpose of suppressing the uneven distribution of the cooling air derived from the internal intake duct 8. is there. That is, even if the cooling air is deflected in the internal intake duct 8, the rectifying means of the present invention can effectively suppress the generation of turbulence and vortex. Therefore, uniform cooling air can be supplied from the internal intake duct 8 to the lower cooling flow path 6. However, the rectification of the cooling air derived from the outlet of the internal intake duct 8 is possible only by providing the rectification means in the internal intake duct 8, but the cooling air flow provided between the cells of the battery module 10 is possible. It is difficult to distribute the cooling air evenly throughout the passage 65. Actually, when a large number of cooling airflow passages 65 configured between adjacent battery cell pairs (the entire main surface 11b of one battery cell 11) are compared in the same main surface 11b, the effect of the pressure difference causes the Y It has been observed that more cooling air tends to flow in the direction of the cooling airflow passage 65 on the downstream side than the cooling airflow passage 65 on the upstream side in the direction. Therefore, in such a cooling air flow velocity distribution state, each battery cell 11 has an in-plane temperature distribution, and there is a possibility that reliable characteristics cannot be obtained.

  Therefore, in the present invention, as a second feature, the cooling airflow passage 65 and / or the housing 2 (more precisely, the upper cooling flow path 5) provided between adjacent battery cells are adjusted as follows. Thus, the flow velocity of the cooling air flowing in the battery module 10 is made uniform, and the temperature distribution generated in the main surface 11b of the battery cell 11 as described above is suppressed. With the first and second features as described above, the battery pack 1 of the present invention enables the battery module 10 to be uniformly cooled while being reduced in height.

  Hereinafter, characteristic portions of the present invention will be described in detail.

  First, the rectifying means provided in the internal intake duct 8 will be described with a specific example.

  FIG. 5 shows the positional relationship between the internal intake duct 8, the internal exhaust duct 9, and the battery module 10. FIG. 6 shows an enlarged perspective view of a portion surrounded by VI in FIG. The internal intake duct 8 has three surfaces perpendicular to the Y direction (first surface 8d1, second surface 8d2, and third surface 8d3 in order from the upstream side in the direction of cooling air flow along the Y direction, respectively). Have On the third surface 8d3 of the internal intake duct 8, openings corresponding to each of the plurality of slits 55 provided as rectifying means are provided in a row in the internal intake duct 8. The plurality of slits 55 extend along the Y direction on the bottom surface of the internal intake duct 8, and extend from the third surface 8d3 to the first surface 8d1 of the internal intake duct 8 on the bottom surface of the internal intake duct 8. It is installed to partition. 5 and 6, the intervals between the slits 55 are shown at equal intervals, but the embodiment of the present invention is not limited to this, and the intervals between the slits 55 gradually decrease as the distance from the intake port increases. It may be set to. However, in order to avoid an increase in design parameters, it is preferable that the slit intervals are equal.

  Since such a plurality of slits 55 are installed in the internal intake duct 8 as rectifying means, even if the cooling air is deflected in the internal intake duct 8, the generation of turbulence and vortex can be effectively suppressed. .

  Next, in the battery module 10, the structure of the cooling airflow passage 65 formed for each main surface 11b of each battery cell 11 will be described.

  FIG. 7 and FIG. 8 schematically show a conventional cooling air passage 65 according to the present invention and formed for each main surface 11b of each battery cell 11, respectively. These drawings correspond to schematic cross-sectional views when the housing 2 is cut between a battery cell and a battery cell adjacent to the battery cell along a plane perpendicular to the X direction in FIG. In the normal battery module 10, as described above, projections for forming a plurality of rows of cooling air flow passages 65 parallel to the height direction of the battery module 10 are provided between adjacent battery cell pairs. Many are provided on the main surface 11b (or one side of the main surface 11b of each battery cell 11). More precisely, the tip of the protrusion installed on the main surface 11b of a certain battery cell 11 is in contact with the main surface 11b facing the adjacent battery cell 11 or is installed on the main surface 11b facing the adjacent battery cell 11. It arrange | positions so that the front-end | tip of protrusion may be touched. As a result, the main surface 11b of the battery cell 11 has a closed portion 64 (hatched portion in FIG. 7) in which the gap between the cells is blocked by the protrusion and the cooling air does not flow, and the cooling air adjacent to the closed portion 64 The flowing cooling air flow passages 65 (outlined portions) are alternately formed. Accordingly, the cooling air from the lower cooling flow path 6 flows through the cooling air flow passage 65 (outlined portion) in the battery module 10 and reaches the upper cooling flow path 5.

  Here, in a normal case, the width of the blocking portion 64 is set to be equal on the same main surface 11b by a method such as unifying the shape of the protrusion and the installation interval, and the width of the cooling airflow passage 65 is also the same. In the main surface 11b, it installs so that it may become equal respectively. Further, the repetitive period widths of the closed portion 64 and the cooling air flow passage 65 (the width of the closed portion 64 + the width of the cooling air flow passage 65) are also set to be equal. However, with such an arrangement of the cooling airflow passage 65, the cooling airflow is less likely to flow through the cooling airflow passage 65 on the upstream side in the Y direction (right side in FIG. 7) due to the influence of the shape of the upper cooling flow passage 5. The cooling effect on the upstream side of 10 in the Y direction is reduced.

  On the other hand, the cooling airflow passage 65 formed on the main surface 11b of the battery cell 11 according to the present invention has different dimensions on the upstream side and the downstream side in the Y direction, as shown in FIG. That is, the width of the closed portion 64 is wider on the downstream side than the upstream side in the Y direction, and conversely, the width of the cooling airflow passage 65 is narrower. In such an arrangement of the blocking portion 64 and / or the cooling airflow passage 65, the cooling air hardly flows through the flow path downstream in the Y direction, so that the flow velocity of the cooling air in each cooling airflow passage 65 is made uniform.

  Although FIG. 8 shows that the width of the closed portion 64 on the downstream side in the Y direction is increased and the width of the cooling airflow passage 65 is reduced, the embodiment of the present invention is limited to such a configuration. Of course, any one of the widening of the closed portion 64 and the narrowing of the cooling airflow passage 65 may be used. Conversely, the width of the closed portion 64 and / or the width of the cooling airflow passage 65 may be increased on the upstream side in the Y direction.

  Further, in the example of the figure, about one-third of the closed portions 64 and / or the closed portions 64 installed on the main surface 11b of each battery cell 11 and / or the cooling air flow passage 65 on the downstream side in the Y direction. The cooling airflow passage 65 is configured such that the width of the blocking portion 64 and / or the width of the cooling airflow passage 65 is wider and / or narrower than that on the upstream side. However, this arrangement is an example, and the structure of the blocking portion and / or the flow path is not limited thereto. For example, about the blocking portion 64 and / or the cooling air flow passage 65 of about 1/2 on the downstream side in the Y direction, the width of the blocking portion 64 and / or the width of the cooling air flow passage 65 is wider than that on the upstream side. It may be configured to be narrower. Alternatively, the width of the blocking portion 64 and / or the cooling airflow passage 65 may gradually decrease from the upstream side in the Y direction toward the downstream side.

  What is important is that the main surface 11b of one battery cell 11 has a structure in which the pressure difference of the cooling air flowing through each cooling air flow passage 65 is reduced. Therefore, in practice, the size and period of the closed portion 64 and / or the cooling airflow passage 65 are adjusted according to the degree of deviation of the flow velocity of the cooling air flowing through each cooling airflow passage 65.

  In addition, the shape of the protrusions installed on the main surface 11b of each battery cell 11 is not particularly limited. For example, the protrusions are arranged in parallel in the height direction of the battery module 10 in a plurality of rows. It may be configured by a rib, or may be a plurality of rows of linear ribs. In this case, by changing the rib width and / or the row interval, the width of the closing portion 64 in the second direction, and further, the width and the period width of the cooling airflow passage 65 can be easily changed.

  For example, as one embodiment of the present invention, on the main surface 11b, the repetition period width (width of the closed portion 64 + width of the cooling airflow passage 65) is constant, and the width of the closed portion 64 on the upstream side in the Y direction When the width of the cooling airflow passage 65 is 2: 1, in order to make the width of the cooling airflow passage 65 on the downstream side in the Y direction about 0.6 times that on the upstream side, the protrusions installed on the downstream side in the Y direction The width should be about 1.2 times the upstream protrusion.

  Thus, by providing the rectifying means inside the internal intake duct 8 and further arranging the cooling airflow passage 65 of the battery module 10 as described above, the following effects are produced. First, since the rectifying means such as the slit 55 is provided inside the internal intake duct 8, it is possible to significantly prevent the turbulence of the cooling air that occurs when the flow of the cooling air is deflected in the internal intake duct 8. Furthermore, the cooling air supplied from the internal intake duct 8 to the lower cooling flow path 6 can be evenly introduced into a large number of cooling air flow passages 65 formed in the respective gaps of the adjacent cell pairs. Accordingly, the battery pack can be reduced in height and size, and the battery module 10 can be uniformly cooled.

  Furthermore, in another aspect of the present invention, instead of or in addition to adjusting the width in the Y direction of the blocking portion 64 and / or the cooling airflow passage 65 in one main surface 11b, the housing 2 (to be precise, Change the upstream configuration of the upper cooling flow path 5) in the Y direction. Specifically, the opening 70 is provided on the upper surface of the housing 2 so that the cooling air can easily flow through the cooling air flow passage 65 on the upstream side in the Y direction in the battery module 10 to achieve the above-described effect. Details of this configuration will be described below.

  FIG. 9 is a schematic perspective view of the battery pack shown in FIG. 3 again. However, in this figure, a large number of rectangular openings 70 are provided in a part of the position corresponding to the upper part of the battery module 10 of the housing 2. FIG. 10 shows an upper front view centering on the opening of the housing 2. In FIG. 10, the protrusions, the blocking portions 64, and the cooling airflow passage 65 are not shown for the sake of clarity, and only the gaps 75 between the battery cells caused by the protrusions are shown. Each opening 70 has a predetermined opening width W1 along the X direction, and the position in the X direction is roughly a gap 75 between adjacent battery cells when viewed from above as shown in FIG. Is set to be the center of the opening 70. In the example of the figure, the opening width W2 in the Y direction of the opening 70 is about half of the width in the Y direction of the battery module, and the upstream end of the opening 70 in the Y direction is roughly the battery module. Of the 10 planes substantially perpendicular to the Y direction, it is installed so as to be aligned with the end of the upstream plane.

  By installing such a large number of openings 70 at the above-described position of the housing 2, the cooling air supplied to the lower cooling flow path 6 flows through the cooling air flow passages 65 formed between the battery cells 11. At this time, the pressure difference between the upstream side and the downstream side in the Y direction becomes small, and the cooling air flows uniformly in each cooling air flow passage 65. Therefore, the battery module 10 can be uniformly cooled, and an effect equivalent to that obtained when the arrangement of the cooling airflow passage 65 is adjusted can be obtained.

  Here, the width W1 in the X direction of the opening 70 is preferably approximately twice or more the width in the X direction of the gap 75 between each pair of adjacent battery cells. Even if the opening 70 having a narrower width W1 is provided, the effect of reducing the pressure difference between the upstream side and the downstream side in the Y direction of the lower cooling channel 6 is small, and the cooling air passing through each cooling air flow passage is made uniform. This is because there is a possibility that it cannot be performed sufficiently. However, in practice, the opening width W1 in the X direction of the opening 70 and the opening width W2 in the Y direction can obviously be adjusted according to the degree of deviation of the flow velocity of the cooling air flowing through each cooling air flow passage 65. Further, in the experimental results, it has been confirmed that if the opening width W1 is equal to or larger than the above-described width, the influence of the size of the width W1 on the effect of reducing the pressure difference is small. For example, the opening 70 is formed as shown in FIG. Alternatively, a single large opening having a width slightly smaller than the distance between two end faces perpendicular to the X direction of the battery module 10 may be used. In FIG. 11, it should be noted that both outer ends in the X direction (width W1 side) of this single opening coincide with the outer end portions of the respective openings on both ends in the X direction in FIG. . However, the position of the opening of the present invention in the X direction is not limited to this.

  In addition, the arrangement adjustment (FIG. 8) of the cooling airflow passage 65 formed on the main surface 11b of the battery cell 11 described above and the opening 70 of the upper cooling flow path 5 (that is, the housing 2) may be used in combination. Of course, it is possible. In this case, although the design parameters increase, it is possible to perform more precise flow rate control of the cooling air flowing through the flow path in the battery pack 1.

  Thus, in the battery pack 1 of the present invention, even when the introduction portion of the cooling air into the housing and the exhaust portion are installed on the same side of the housing, the cooling air is deflected in the internal intake duct 8. The turbulence of the cooling air and the deviation of the flow velocity occurring in the above can be suppressed. In addition, the cooling air derived from the outlet of the internal intake duct 8 flows through each cooling air flow passage 65 provided in the battery module 10 evenly. Accordingly, the battery pack 1 can be lowered in height, and the battery module 10 can be uniformly cooled, so that a local temperature rise can be suppressed.

  In each of the above embodiments, the case where air in the vehicle compartment is used as the refrigerant of the battery pack 1 has been described as an example. However, other refrigerant gas or liquid may be used. These refrigerants may be circulated through a heat exchanger or the like.

  Furthermore, in the present invention, it should be noted that the internal intake duct, the battery module, and the internal exhaust duct may be configured in the housing in any arrangement relationship as long as the same effect can be obtained.

It is a figure which shows the mounting state to the vehicle of a battery pack. It is a block diagram in the case of driving a vehicle with a battery system having a battery pack according to the present invention. 1 is a schematic perspective view of a battery pack according to a first embodiment of the present invention. FIG. 4 is a schematic cross-sectional view taken along line III-III in FIG. FIG. 3 is an exploded perspective view showing a positional relationship between an internal intake duct, an internal exhaust duct, and a battery module of the battery pack according to the present invention. FIG. 6 is an enlarged view of a portion surrounded by VI in FIG. FIG. 6 is a schematic cross-sectional view along the Y direction of a housing and a battery module, showing a configuration of a conventional cooling airflow passage 65 formed on the main surface 11b of the battery cell. FIG. 6 is a schematic cross-sectional view of the housing and the battery module along the Y direction, showing the configuration of the cooling airflow passage 65 of the present invention formed on the main surface 11b of the battery cell. 4 is a schematic perspective view of a battery pack according to a second embodiment of the present invention. FIG. FIG. 10 is a top front view of a part of the housing of FIG. FIG. 6 is a top front view of a part of another housing according to the second aspect of the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Battery pack 2 Case 3 Upper case 4 Lower case 5 Upper cooling flow path 6 Lower cooling flow path 7a 1st side space 7b 2nd side space 8 Internal intake duct 8a Intake port 8d1 Y direction of internal intake duct 8d2 Second surface perpendicular to the Y direction of the internal intake duct 8d3 Third surface perpendicular to the Y direction of the internal intake duct 9 Internal exhaust duct 9a Exhaust port 10 Battery module 11 Battery cell 11a Projection Part 11b Main surface 15 End plate 30 Equipment box 33 Bolt 55 Slit 64 Blocking part 65 Cooling air flow passage 70 Opening 75 Clearance 80 External intake duct 90 External exhaust duct 100 Vehicle 101 Control part 102 Battery part 103 Drive part 500 Rear seat.

Claims (9)

A battery module configured by stacking a plurality of cells in the housing, an internal intake duct for supplying the refrigerant introduced into the housing through the refrigerant inlet in the direction of the battery module, and from the direction of the battery module An internal exhaust duct that discharges the derived refrigerant to the outside of the housing through the refrigerant discharge port, and a battery pack,
The refrigerant introduction port and the refrigerant discharge port are installed on the same surface side of the housing, the refrigerant introduction port guides the refrigerant passing through the refrigerant introduction port in a first direction,
The internal intake duct has rectifying means for deflecting the refrigerant derived from the outlet of the internal intake duct in a second direction substantially perpendicular to the first direction,
Each cell has a large number of flow paths through which refrigerant flows between adjacent cells,
The number of the flow paths is different between the upstream side and the downstream side in the second direction, and / or the housing has an opening at a part of the position corresponding to the upper part of the battery module. Battery pack. The rectifying means is composed of a plurality of slits installed on the bottom surface of the internal intake duct,
Each of the plurality of slits has a respective opening at the outlet of the internal intake duct, and is installed so as to partition the bottom surface of the internal intake duct substantially along the second direction. 2. The battery pack according to claim 1, wherein:   2. The plurality of flow paths are selected from two types of dimensions, and are selected to have a large dimension on the upstream side in the second direction and a small dimension on the downstream side. Or the battery pack as described in 2.   3. The battery pack according to claim 1, wherein the size of the plurality of flow passages gradually decreases from the upstream side to the downstream side in the second direction.   The plurality of flow passages are formed between protrusions that are provided on at least one surface of an opposing surface that faces an adjacent cell of each cell, according to any one of the preceding claims. Battery pack.   6. The battery pack according to claim 5, wherein the protrusion is composed of a plurality of linear ribs installed in parallel along the height direction of the battery module.   The battery pack according to any one of the preceding claims, wherein the first direction is a direction substantially parallel to a cell stacking direction. The opening comprises a plurality of openings,
The position of the plurality of openings in the first direction is set at a location approximately corresponding to the upper part of the gap formed between each cell and the cell adjacent to the cell,
The position of the opening in the second direction is set approximately at a position corresponding to the upper part of the region from the upstream side surface in the second direction of the battery module to the central portion in the same direction. The battery pack according to claim 7. The opening comprises a single opening;
The position of the single opening in the first direction is set at a location approximately corresponding to the upper part of the region between the two side surfaces perpendicular to the first direction of the battery module,
The position of the opening in the second direction is approximately installed at a location corresponding to the upper part of the region from the upstream side surface in the second direction to the central portion in the same direction. The battery pack according to claim 7.

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