JP5461341B2 - Battery cooling structure - Google Patents

Description

The present invention relates to a cooling structure for a battery (particularly an assembled battery). In particular, the present invention relates to an air-cooled battery cooling structure for cooling a battery with cooling air.

In an electric vehicle, a hybrid vehicle, and the like, an assembled battery in which secondary batteries are assembled as a power source is used. In the process of charging or discharging, if the battery overheats or the temperature difference between the batteries increases, the performance of the battery may deteriorate or the battery may be damaged. Usually, these assembled batteries are stored in the battery case. Then, cooling air is sent into the battery case to cool the assembled battery.

In cooling, it is necessary to equalize the temperature of a plurality of batteries constituting the assembled battery as much as possible and cool the batteries efficiently. For this reason, various battery cooling structures have been proposed.
For example, Patent Document 1 discloses a cooling structure in which a plurality of air guide plates are provided on the cooling air inlet side of the battery case so that the cooling air passing between the air guide plates is directed between the battery modules. Has been. Further, Patent Document 2 includes an induction member that defines an intake portion and an exhaust portion for each of the battery modules and induces a flow of cooling air between the electronic modules. A battery cooling structure configured to supply new cooling air to the module is disclosed.

Japanese Patent Application Laid-Open No. 2004-71394 JP 2008-130330 A

In these battery cooling structures, the battery modules are often arranged in a plurality of rows from the upstream side to the downstream side. In this case, the cooling air is warmed by cooling the upstream battery module. The cooling of the battery module on the downstream side is insufficient, and the battery temperature tends to be insufficiently uniform.
The conventional technique disclosed in the above document is also positioned as an invention intended to solve such a problem of uniform battery temperature. However, the inventors have found that the following problems have been found.

That is, in the battery cooling structure described in Patent Document 1, although the flow that has passed between the air guide plates is configured to pass between the upstream battery modules, the cooling of the battery modules in the middle and lower stages is not possible. It turned out to be sufficient. As a result of investigating and examining the cause, in such a battery cooling structure, when the flow passing between the air guide plates passes between the battery modules, the flow momentum is easily lost, and the flow momentum is lost. In addition to difficulty in applying cooling air to the battery modules in the middle and subsequent stages, there is a problem that the cooling air warmed by cooling the upstream battery and the new cooling air are likely to be mixed. It has been found.

In addition, in the battery cooling structure as described in Patent Document 2, since a new cooling air is supplied to each battery module, the battery cooling conditions can be made uniform and the temperature of the battery module can be made uniform. Therefore, it is necessary to provide a wind guide plate having a complicated shape around the battery module, and a battery cooling structure having a simpler structure has been demanded from the viewpoint of cost and manufacturing efficiency.

That is, an object of the present invention is a battery that has a simple structure and can supply cooling air accurately to the battery modules in the second and subsequent rows to cool the temperatures of the battery modules constituting the assembled battery more uniformly. It is to provide a cooling structure.

In the battery cooling structure disclosed in Patent Document 1, the inventors of the present invention investigated the cause of insufficient battery temperature uniformity. As shown in FIG. Even if the air guide plate P is provided with slits S, S so that the cooling air is directed therebetween, the cooling air that has passed through the slit S is diffused in the space between the air guide plate and the upstream battery module. , It loses its momentum rapidly, and the upstream battery module is cooled and mixed with warm cooling air and fresh cooling air. It has been discovered that fresh cooling air is unlikely to be supplied around the battery modules after the midstream, such as meandering. Further, the air passing between the slit S and the upstream battery module loses momentum and is diffused, and the cooling air cannot be successfully applied to the middle and downstream battery modules, which deteriorates the cooling performance. I found out that

Furthermore, the inventors of the present invention, as a result of intensive studies, have the flow control plate provided upstream of the assembled battery as a specific form and supply the cooling air supplied to the most upstream battery module and the battery modules after the middle stream. The cooling air is partitioned from each other, and in the space between the most upstream battery modules, these two cooling air flows are merged, and the cooling air that cools the middle and subsequent battery modules is sent to the uppermost battery module. Surprisingly, the cooling air that cools the battery modules after the middle stream can be delivered to the battery modules after the middle stream without losing the momentum of the flow. It was found that the temperature of the battery constituting the assembled battery could be made more uniform, and the present invention was completed.

The present invention stores a battery pack in which a plurality of battery modules are arranged in a plurality of rows in a battery case, introduces cooling air into the battery case from a cooling air inlet provided in the battery case, and Is cooled with cooling air, and the cooling air is discharged outside the battery case from the cooling air outlet provided in the battery case, and the battery case has an upstream side of the battery module in the uppermost stream. A flow control plate that divides the inside of the battery case into a downstream side and an upstream side is provided, and the flow control plate is configured by connecting unit rectifier plates that extend in the battery length direction, The flow control plate is provided with a through hole that communicates the flow upstream side and the downstream side with each other, and the unit rectifying plate forms a part of the upstream surface of the battery module with respect to each of the battery modules in the most upstream row. At predetermined intervals The unit rectifying plate is provided with a first through hole for introducing cooling air into each uppermost stream battery module, and is connected to the unit rectifying plate. The portions adjacent to each other are the second through holes, and the second through holes are provided in the space between the adjacent most upstream battery modules and introduced from the second through holes. The battery cooling structure is characterized in that the cooling air is not applied to the uppermost battery module.

In the present invention, it is preferable that the second through hole be opened between the adjacent side portions of the most upstream battery module (second invention).

Furthermore, in this invention, it is preferable that a battery module is a column shape and a unit rectifier plate is formed in cross-sectional arc shape (3rd invention). Moreover, in this invention, it is preferable that the cooling air introduced from the 2nd through-hole is comprised so that it may send toward the battery module of a 2nd row (4th invention). Moreover, in this invention, it is preferable that a battery module is arrange | positioned at zigzag form (5th invention).

According to the present invention, the flow fa introduced from the first through hole to cool the uppermost battery module and the new cooling air flow fb introduced from the second through hole are downstream of the second through hole. A laminar flow structure in which the flow fb is sandwiched by the flow fa is realized. With such a laminar flow structure, the new cooling air flow fb introduced from the second through hole is delivered to the downstream battery module as new cooling air without cooling the uppermost battery module. As a result, it is possible to effectively cool the battery modules arranged in the middle stream or downstream, and to obtain the effect that the temperatures of the batteries constituting the assembled battery can be more effectively made uniform.

In the present invention, when the second through hole is opened between the adjacent side portions of the most upstream battery module as in the second invention, the second through hole Thus, it is possible to more reliably prevent the new cooling air introduced from the above from being blown to the uppermost battery module, and to make the battery temperature more uniform.

Furthermore, in the present invention, as in the third invention, when the battery module is formed in a columnar shape and the unit rectifying plate is formed in a circular arc shape, the flow fa from the first through hole and the flow from the second through hole. fb can be more effectively rectified into layers, and this flow can be reliably delivered to the battery modules in the second and subsequent rows, and the above-described effects can be more reliably exhibited.

Furthermore, in the present invention, when the cooling air introduced from the second through hole is sent toward the second row of battery modules as in the fourth invention, the second row of battery modules Can be effectively cooled, and the above-described effects can be exhibited more reliably.

Furthermore, in the present invention, if the battery modules are arranged in a staggered manner as in the fifth invention, the cooling air introduced from the second through holes is surely sent toward the battery modules in the second row. It is possible to exert the above-described effect more reliably.

It is sectional drawing which shows the battery cooling structure of 1st Embodiment of this invention. It is sectional drawing which expands and shows the flow control board vicinity of 1st Embodiment of this invention. It is a schematic diagram which shows the flow of the flow control board downstream in 1st Embodiment of this invention. It is a figure which shows the simulation result of the cooling air flow in 1st Embodiment of this invention. It is a figure which shows the simulation result of the cooling wind flow in the conventional battery cooling structure. It is a figure which shows the example of the conventional battery cooling structure. It is a graph of the simulation result of the surface temperature of a battery module. It is sectional drawing which shows the battery cooling structure of 2nd Embodiment of this invention. It is a figure which shows the simulation result of the cooling air flow in 2nd Embodiment. It is a graph of the simulation result of the surface temperature of the battery module in 2nd Embodiment. It is sectional drawing which expands and shows the flow control board vicinity in other embodiment of this invention. It is a schematic diagram which shows the cooling air flow in the conventional battery cooling structure.

Hereinafter, an embodiment of a battery cooling structure of the present invention will be described with reference to the drawings, taking as an example a battery case for storing a battery pack for a hybrid vehicle. FIG. 1 is a cross-sectional view of the embodiment of the battery cooling structure of the present invention along the flow direction of cooling air. FIG. 2 is an enlarged sectional view showing the vicinity of the flow control plate of the battery cooling structure of the present embodiment.

In the internal space of the box-shaped battery case 1, rod-shaped battery modules 2 and 2 are arranged in parallel at a predetermined interval. The battery modules 2 and 2 are electrically connected in series or in parallel to form an assembled battery. In the present embodiment, the battery constituting the battery module is a nickel metal hydride battery, and the battery module 2 in which the batteries are connected in series has a cylindrical bar shape.

In FIG. 1, the battery modules 2 and 2 are arranged so as to extend in the depth direction of the drawing, and 15 battery modules (or dummy modules) are arranged in multiple rows of 3 rows × 5. . In the present embodiment, the battery modules are arranged in a staggered manner such that the downstream battery modules are positioned between the upstream battery modules. Each of the battery modules 2 and 2 has a predetermined interval (gap) between the inner surface of the battery case 1 and an adjacent battery module, and a spacer or a support member allows the cooling air to flow through the gap. The battery case is housed and supported. In the present embodiment, the cooling air flows as a whole from the upper side to the lower side of the figure, and in that sense, in the following description, three rows of battery modules arranged in a staggered manner are described below. , May be referred to as an upstream (uppermost row or upper) battery module, a middle (second row or middle) battery module, and a downstream (third row or lower) battery module.

The battery case 1 is a hollow box-shaped member formed of metal or synthetic resin. The battery case 1 is provided with a cooling air inlet 11 and a cooling air outlet 12 to cool the internal space of the battery case 1. It becomes a wind passage. The battery case 1 is used for cooling the assembled battery by connecting the cooling air inlet 11 and the cooling air outlet 12 with peripheral members such as a duct and a blower fan to form a series of cooling air passages.

In this embodiment, a blower fan (not shown) is provided on the downstream side of the cooling air outlet 12 and is connected to the upstream side of the cooling air inlet 11 on the upper side of the drawing (not shown). Then, the cooling air flows into the battery case 1, cools the battery while passing through the gap between the battery modules 2, 2 and the battery case 1, and is heated from the cooling air outlet 12 to the lower side of the figure. Cooling air begins to flow.

In the present invention, a flow control plate 13 is provided inside the battery case 1 so as to partition the internal space of the battery case into a cooling air inlet side and a cooling air outlet side, and to block the flow of the cooling air. Yes. Then, the flow control plate 13 is located in a region (position) upstream from the battery modules 2 in the uppermost stream (upper stage), that is, in a region (position) upstream from all the battery modules (assembled batteries). The battery case 1 is integrally attached.

As shown in FIG. 2, the flow control plate 13 has a corrugated plate-like unit rectifying plate 131, 131 extending in the length direction of the battery module so as to form a corrugated plate as a whole. Consecutive configuration. The unit rectifying plates 131 and 131 are provided corresponding to the battery modules 2u and 2u in the uppermost stream. The flow control plate 13 is provided with a plurality of through holes (opening holes) 132a and 132b along the length direction of the battery module (in the depth direction of FIG. 2).
The internal space of the battery case 1 divided into the upstream side and the downstream side by the flow control plate 13 is connected to the upstream side and the downstream side through the through holes 132a and 132b, and is provided on the downstream side. The assembled battery (battery modules 2, 2) is cooled by cooling air introduced from these through holes.

The structure of the flow control plate 13 in this embodiment will be described in more detail.
The unit rectifying plate 131 and the battery module are arranged in a predetermined manner so as to cover at least a part of the upstream surface of the battery module 2u in the uppermost stream (about 2/5 of the circumference of the battery module in this embodiment). It is provided in a bowl-like shape that is spaced apart. In the present embodiment, the unit rectifying plate 131 is formed in a bowl-like shape having an arc-shaped cross section with a certain interval with respect to the cylindrical battery module. The end portions (edges) 131a and 131a of the unit rectifying plates 131 and 131 adjacent to each other are arranged so as to be spaced from each other by a predetermined distance, and the space therebetween functions as a slit-shaped through hole (132b). ing.

The first through holes 132a and 132a are formed in the most upstream part of the unit rectifying plates 131 and 131, that is, in the unit rectifying plate part (directly above) located upstream from the center of the most upstream battery module. Is provided. The cooling air introduced from the through-hole 132a is blown to the uppermost battery module 2u immediately below the cooling air, and cools the uppermost battery module 2u, and between the unit rectifying plate 131 and the uppermost battery module 2u. It flows through the gap.

On the other hand, second through holes 132b and 132b are formed between the unit rectifying plate edges 131a and 131a arranged at a predetermined interval from each other. The through holes 132b and 132b are provided so as to be positioned in a space between the most upstream battery modules 2u and 2u, that is, in a space C surrounded by a broken line in FIG. 2, and particularly in the present embodiment, the most upstream battery. The module is provided in the middle of the battery module in the vicinity of a portion close to each other (that is, a side portion of the most upstream battery module). From the viewpoint of simplifying the shape of the flow control plate 13, the through hole 132b is preferably provided on the upstream side of the line m connecting the centers of the most upstream battery modules.

The cooling air introduced from the second through holes 132b and 132b is not directly blown onto the surface of the most upstream battery module depending on the shape of the unit rectifying plates 131 and 131 and the position of the second through holes 132b (that is, The cooling air does not hit the uppermost stream battery module). That is, the cooling air passing through the second through hole mainly cools the battery modules after the middle stage. More specifically, in the present embodiment, the through hole 132b is located in the middle of the most upstream battery module, and the arc-shaped unit rectifier plates 131 and 131 are provided symmetrically, and are adjacent to each other in the most upstream row. A through hole 132b is opened between the side portions of the battery module, and the cooling air passing through the through hole 132b does not go to the uppermost battery module, but in the downstream direction (that is, directly below the figure). Direction)).

In the present embodiment, since the battery modules are arranged in a staggered manner, the cooling air flow toward the downstream side through the second through hole 132b is sent to the battery modules in the second row as it is. It will be.

Here, these 1st and 2nd through-holes are formed so that it may become a long hole or slit shape extended along the length direction of a battery module. These through holes are provided over the entire length of each battery module.

The main specific dimensions of the arrangement of the battery modules and the flow control plate 13 in this embodiment are as follows. The battery modules 2 and 2 are arranged in a three-row by five zigzag pattern, the battery module 2 has a diameter of 32 mm, and the left and right intervals between the centers of the battery modules are 41 mm.

The flow control plate 13 is provided so that a bowl-shaped unit rectifying plate 131 having an arc cross section is located at a position 3 mm away from the upstream (upper) battery module surface upstream. The width of the first through hole 132a provided in the most upstream portion of the unit rectifying plate (left and right direction in FIG. 2) is 4 mm. The unit rectifying plate 131 is provided with a thickness of 2 mm so that the edge portion 131a is located at a position 6 mm away from the line m connecting the centers of the uppermost battery modules on the upstream side. The width of the second through hole 132b is 3 mm.

The battery case constituting the battery cooling structure can be manufactured by a known manufacturing method. For example, the battery case 1 is made of a synthetic resin (for example, polypropylene resin) in which a case member divided into an open box and a lid is formed. It can be formed by injection molding. The flow control plate 13 can also be formed by injection molding of synthetic resin (for example, polypropylene resin), and may be integrally formed with the case member of the battery case 1 if possible. Of course, the flow control plate 13 may be formed separately from the case by injection molding of a metal plate or synthetic resin and attached at a predetermined position when the battery case is assembled.

A battery case in which battery modules are arranged at predetermined positions in the battery case 1, wiring between the battery modules is established, the lid of the battery case is closed in a state where the flow control plate is incorporated, and the assembled battery of the above embodiment is stored And the battery cooling structure is completed.

The operation and effect of the battery cooling structure of the present invention will be described.
In the battery cooling structure of the present invention, the flow (fb) of the cooling air that has passed through the second through hole 132b due to the interaction between the through holes 132a and 132b provided in the flow control plate 13 and the unit rectifying plate 131, It becomes a flow that is sandwiched by the cooling air flow (fa) that has passed through the first through hole and has flowed between the most upstream battery module 2u and the unit rectifying plate.

If it demonstrates based on the said embodiment, in FIG. 3, the cooling air which flows in from the upper side of a figure will pass through the through holes 132a and 132b, and will flow into the space in which the battery modules 2 and 2 were accommodated. Here, the cooling air that has passed through the first through hole 132a is blown to the battery module 2u in the uppermost stream, and flows along the space between the battery module 2u and the bowl-shaped unit rectifying plate 131 ( Flow fa).

On the other hand, the flow fb that has passed through the second through hole 132b is adjacent to the battery modules 2u and 2u in the most upstream row because of the end shape of the unit rectifying plate 131 and the position where the second through hole 132b is disposed. Will flow toward the side to be.

In the present embodiment, the flow fa from the first through hole and the flow fb from the second through hole described above are downstream of the end 131a of the unit rectifying plate 131 (that is, downstream of the second through hole 132b). The flow fb from the second through hole is sandwiched by the flows fa and fa from the first through hole, and these flows are rectified in layers. In this state, it will flow downstream.

In the present invention, the cooling air flowing out from between the uppermost battery modules can be made into a flow rectified in a layered manner such that the new cooling air fb is sandwiched by the flow fa. In this flow, the laminar flow structure and momentum are easily maintained, and a new cooling air flow fb is diffused in the expansion space between the uppermost stream battery module 2u and the middle stream battery module 2m. Stalling is prevented or suppressed.

Then, the new cooling air fb from the second through hole reaches the middle battery module surface 2m without losing its momentum, branches and flows along the middle battery module surface.

Thus, according to this embodiment of the present invention, the new cooling air flow fb supplied from the second through hole 132b can be delivered to the periphery of the middle battery module 2m without losing its momentum. And the middle battery module can be effectively cooled.

Further, in the present embodiment, the second through hole 132b is opened between adjacent side portions of the most upstream battery module. Therefore, the flow of the cooling air that has passed through the second through hole is reliably prevented from being blown to or hitting the battery modules in the uppermost stream, and the layered flow structure allows the cooling air to flow downstream as a new cooling air. It has the advantage of being delivered to the side battery module.

This flow field is shown in FIG. 4 as a streamline diagram obtained by a numerical fluid simulation. FIG. 4 is a streamline diagram of a region surrounded by a broken line in FIG. 1 as a result of the numerical simulation performed by the battery cooling structure of the first embodiment shown in FIG. In the figure, the thin streamline is a streamline indicating the flow fa of cooling air passing through the first through hole 132a, and the dark streamline is the flow of cooling air fb passing through the second through hole 132b. It is the streamline which shows.

As shown in the simulation results, the cooling air flow fa passing through the first through hole 132a and the cooling air flow fb passing through the second through hole 132b are determined by the end 131a of the unit rectifying plate, that is, the second through hole 132b. In a portion immediately below the provided position, the flow becomes a substantially parallel flow and merges, and the flow fa and the flow fb become a laminar flow in a sandwich shape and flow toward the battery modules in the second row. In the space between the battery module in the uppermost stream and the battery module in the second row, the structure of the laminar cooling air flow is maintained, and the flow of fresh air is maintained at the center without losing the momentum of the flow. With the flow fb maintained, the flow collides with the battery modules in the second row, and the air of the new cooling air flow fb that has passed through the second through holes is supplied to the surface of the second row battery modules. A state of being observed is observed.

On the other hand, in the simulation result of the battery cooling structure having the conventional structure, it was difficult to successfully deliver the new cooling air to the surface of the second row battery module. As an example, a similar numerical fluid in a battery cooling structure in which a substantially flat flow control plate P having a through hole S is provided at a position corresponding to between the most upstream battery modules and a position directly above the most upstream battery module. Simulation was performed (comparative example, FIG. 5 and FIG. 6). In addition, in the simulation of the comparative example, the battery cooling structure disclosed in Patent Document 1 and the point where the battery modules are arranged in a lattice shape, and the position and orientation of the cooling air inlet and the cooling air outlet are common. Calculation is performed for a battery cooling structure of the type shown in FIG. As will be apparent from a comparison between the second embodiment to be described later and this comparative example, even if the battery module has a grid-like arrangement or a difference in the arrangement or orientation of the cooling air inlet, With respect to the subject of the present invention of accurately controlling the flow of cooling air from between the modules to the battery modules in the middle and subsequent stages, no significant difference appears.

FIG. 5 shows a simulation result of the comparative example. In FIG. 5, the cooling air that has passed through the through holes of the flow control plate and flows in the vicinity of the battery modules in the uppermost stream is represented by light colored streamlines at the uppermost stage. The cooling air flowing to the downstream battery module without flowing in the vicinity of the battery module is indicated by a dark streamline. In the comparative example, it is observed that the flow meanders and the momentum is lost in the space between the battery modules, in particular, the space provided between the battery modules. As a result of the loss of flow momentum, it becomes difficult to control the flow toward the battery modules in the middle and subsequent stages, and new cooling air (color While there are battery modules that can deliver dark streamlines), there are battery modules that only supply cooling air (light-colored streamlines) that is warmed by cooling the upper battery module, such as the middle battery module in the figure. Thus, it is observed that new cooling air cannot be delivered accurately to each of the middle-stage battery modules. With such a cooling air flow, the cooling of the battery varies, and the temperature uniformity of the battery module tends to be impaired.

As described above, according to the above-described embodiment of the present invention, the flow structure of the cooling air flowing from between the upper battery modules toward the subsequent battery module is changed to the new cooling air that has not been applied to the uppermost battery module. The uppermost battery module can be made into a flow structure rectified in a layered manner such that it is sandwiched with cooled air, and a new cooling air flow can be accurately delivered to the subsequent battery module. Then, the subsequent battery modules can be efficiently cooled.

Therefore, according to the present invention, a new cooling air flow can be effectively guided around the battery modules in the middle and lower stages by the flow control plate having a simple structure provided upstream of the most upstream battery module. The temperature difference between the battery modules constituting the assembled battery can be reduced, and the battery temperature can be made uniform effectively.

In order to confirm the effect of equalizing the battery temperature, in the numerical fluid simulation, a predetermined heat generation amount was set for each battery module, and a cooling temperature simulation for each battery module was performed. In the cooling temperature simulation, the surface temperature of the most upstream battery module and the middle and most downstream battery modules are evaluated, and the specifications of the battery cooling structure with the same cooling air volume and specifications (battery diameter, arrangement, heat generation, etc.) Compared by difference. The battery surface temperature is evaluated for each of the battery modules shown in FIG. 1 and FIG. 6 in the upper battery module: upper 1, upper 2, upper 3, upper 4, upper 5 (numbered in order from the left), middle battery For the module, 1st, 2nd, 3rd, 3rd, 4th, and 5th (numbers are in order from the left), and for the lower battery modules, the bottom 1, bottom 2, bottom 3, bottom 4, bottom 5 (numbers are from the left) The average of the battery surface temperature in the surface of each battery module was calculated.

The result of the cooling temperature simulation is shown in the graph of FIG. In FIG. 7, the horizontal axis indicates the battery modules identified, the vertical axis indicates the battery surface temperature, and the vertical scale indicates 1 ° C. on one scale. According to the result of the simulation, in the result of the comparative example shown in FIG. 5, a temperature difference of slightly over 4 ° C. was generated between the upper battery module and the middle battery module. In the results of the example (Example 1), the temperature of the middle battery module is effectively lowered, and the temperature difference between the upper battery module and the middle battery module can be reduced to less than 1 ° C. That is, in the simulation result of the embodiment of the present invention, it was confirmed that the surface temperature of the battery module was effectively uniformed particularly in the upper battery module and the middle battery module.

The present invention is not limited to the above embodiment, and can be implemented with various modifications. Other embodiments of the present invention will be described below. However, in the following description, portions different from the above-described embodiment will be mainly described, and descriptions of the same portions will be omitted.

An example of change in the overall configuration of the battery cooling structure is shown in FIG. 8 (second embodiment). In the present embodiment, similarly to the above-described comparative example (FIG. 6), the battery case 3 is provided with a cooling air introduction port 31 on the upper left side, and the cooling air is directed from the introduction port 31 toward the right side of the drawing. The entire cooling air passage is configured so that the cooling air that has been introduced and cools the assembled battery is discharged toward the right side from the cooling air discharge port 32 provided on the lower right side of the battery case. Yes. And each battery module 2 and 2 which comprises an assembled battery is arranged in a grid | lattice form in this embodiment. And in the area | region upstream from an assembled battery, the flow control board 13 which partitions off the internal space of the battery case 3 into the upstream and downstream is arrange | positioned. The flow control plate 13 is configured similarly to the flow control plate of the first embodiment. Similarly to the flow control plate of the first embodiment, a second flow control plate 34 that can control the flow of cooling air around the downstream battery module is also provided in the downstream region of the assembled battery. .

The result of the numerical fluid simulation in the second embodiment is shown in FIG. Also in the present embodiment, a new cooling air flow fb (flow indicated by a dark streamline) that has passed through the second through hole has passed through the first through hole and has cooled the uppermost stream battery module (fa) The flow is sandwiched between the color streamlines) and flows between the upper battery modules in a layered flow, and reaches the middle battery module surface with the flow fb maintaining its momentum. Thus, the middle-stage battery module can be effectively cooled.

FIG. 10 shows the simulation results of the battery surface temperature of the second embodiment. Also in this embodiment, the temperature difference between the upper battery module and the middle battery module is within a range of just over 1 ° C., and the battery temperature is It is maintained uniformly.

As described above, the battery modules may be arranged in a lattice pattern, or the flow direction in the upstream region of the flow control plate 13 (for example, the flow direction from the top to the bottom in the drawing in the first embodiment, the second In the embodiment, the flow direction from the left to the right in the figure is not particularly limited.

If the battery arrangement is staggered, the cooling air that has passed between the upper battery modules can easily form a flow field that directly strikes the middle battery module, which is particularly preferable in practicing the present invention.

When the battery modules are arranged in a grid, the cooling air flow that has passed between the upper battery modules is blown to the middle or more downstream battery module, that is, as shown in FIG. In addition, the flow may be deflected with respect to the grid arrangement of the battery modules. Various means can be adopted as the technical means for changing the flow. For example, as in the second embodiment of FIG. 8, the cooling air is introduced to the right from the cooling air introduction port, the flow field is directed downward around the battery module, and the cooling air is discharged to the right from the cooling air discharge port. Thus, if it comprises the whole, the flow around a battery module will become a flow which deflected to the right a little. Alternatively, in the flow control plate (13, 34) provided upstream or downstream of the battery module, the size of each through hole is adjusted (for example, the through hole becomes larger toward the left side in the upstream flow control plate). Thus, the flow around the battery module can be deflected by adjusting the arrangement of the through-holes so that the through-hole becomes larger toward the right side in the downstream flow control plate. Of course, depending on the shape of the upstream flow control plate, the flow can be deflected in a predetermined direction, or another flow control plate can be arranged around the battery module to deflect the flow.

FIG. 11 shows an enlarged view of the vicinity of the flow control plate in the third embodiment in which the specific shape of the flow control plate is further changed with respect to the second embodiment. The shape of the flow control plate 33 and the unit rectifying plate 331 constituting the flow control plate in this embodiment will be described. In the present embodiment, the edge member is erected obliquely at both ends of the central member provided in a substantially flat plate shape, and the unit rectification is performed in a bowl shape having an open U-shaped cross section as a whole. The plate 331 is formed.

The central member of the unit rectifying plate 331 is provided with two first through holes 332a, and the cooling air passing through the first through holes cools the battery modules in the uppermost stream. And between the mutually adjacent edge parts of the unit baffle plate 331, it is set as the 2nd through-hole 332b similarly to 1st Embodiment, and the cooling wind which passes the 2nd through-hole 332b is after the 2nd row. Used for cooling battery modules.

Also in the present embodiment, the cooling air flow fa that flows between the unit rectifier plate and the battery module while passing through the first through hole and cooling the most upstream battery module, and the second through hole are passed. Then, the cooling air flow fb flowing between the most upstream battery modules merges substantially in parallel to form a laminar flow structure in which the flow fb is sandwiched by the flow fa, and the second through-holes are formed. The momentum of the derived new cooling air flow fb is maintained, and the battery module reaches the middle and subsequent stages in a state where the laminar flow structure is maintained.

Thus, the detailed shape of the unit rectifying plate in the present invention is not particularly limited as long as it is a bowl-shaped member provided so as to cover at least a part of the upstream portion of the most upstream battery module.
That is, the unit rectifying plate constituting the flow control plate in the present invention is not limited to the rectifying plate having an arc-shaped cross section as in the first embodiment or the second embodiment, but has a corner as in the third embodiment. It can be set as the bowl-shaped unit control board of various forms, such as a shape. In addition, when adopting a cylindrical shape as the battery module, in particular, by making the unit rectifier plate having a circular arc cross section, the air flow between the battery module and the unit rectifier plate becomes smooth, and as a result The rectifying effect at the time of flowing through the second through hole is enhanced, and the stall of the new cooling air flow fb is prevented more effectively, and the new cooling air is applied to the battery modules after the middle stage. It is preferable to be delivered.

In addition, in the portion where the end portions of the unit rectifying plate face each other, that is, around the second through hole, the end portion of the unit rectifying plate has a so-called funnel shape (eg, the first embodiment, FIG. 2) or a funnel shape (eg, The shape of the third embodiment, FIG. 11) is preferable, and in this case, the momentum of the cooling air passing through the second through hole increases, and the battery modules in the middle and subsequent stages Easier to reach.

Further, the gap between the end of the unit rectifying plate and the most upstream battery module is made constant along the flow direction, or the gap gradually decreases as shown in the third embodiment. Preferably, the momentum of the cooling air flow fa sandwiching the new cooling air fb increases, and the new cooling air can easily reach the battery modules in the middle and subsequent stages. it can.

In the description of the above embodiment, the description has been made mainly on the embodiment in which the cooling air that has passed between the upper battery modules is blown to the middle battery module, but the lower battery module or the third and subsequent battery modules. It is also possible to constitute the battery cooling structure of the present invention so as to spray on. In such a case, for example, if the assembled battery has a three-stage configuration, the upper stage and the middle stage are arranged in a lattice pattern, and the middle stage and the lower stage are arranged in a staggered pattern. This is a preferred embodiment in terms of increasing the cooling efficiency.

The present invention is characterized in that the new cooling air flow fb from the second through hole is sandwiched by the flow fa from the first through hole, and the new cooling air is delivered to the battery modules in the second and subsequent rows. However, if this flow is sent to the middle stage (that is, the second row) battery module, the laminar flow structure and momentum can be easily maintained, and the flow can be easily stabilized. Can be cooled. Therefore, in the implementation of the present invention, it is particularly preferable that the cooling air introduced from the second through hole is sent toward the middle (second row) battery module.

Further, in the description of the above embodiment, the form in which the assembled battery is stored in the hollow box-shaped battery case 1 has been described, but the embodiment of the battery case is limited to a hollow box-shaped one that is molded exclusively for the case. The battery case may be configured by combining a plurality of members such as a panel member and a block member. For example, an assembled battery is arranged on a floor panel of a vehicle body, a heat insulating panel or an electrode panel is provided so as to surround the assembled battery, and a battery case having a cooling air passage between the floor panel, the heat insulating panel, and the electrode panel is provided. It can also be configured. As described above, the battery case according to the present invention includes a battery case constituted by using / combining a member arranged around the assembled battery, in addition to the battery case constituted by a dedicated component member.

Examples of the battery constituting the assembled battery include a primary battery, a secondary battery (such as a lithium ion battery, a nickel hydride battery, and a nickel cadmium battery), a double electric capacitor, and the like. In the above embodiment, the battery module has been described as being rod-shaped and particularly cylindrical. However, the battery module is not limited to the cylindrical shape, and may be prismatic.

In the above embodiment, the battery modules of the assembled battery are arranged in the three-stage grid pattern or zigzag pattern from the upstream to the downstream of the flow around the battery module. The arrangement of the battery modules is not limited to three stages, and may be two stages or four or more stages along the flow direction. As described above, the present invention is particularly effective in effectively increasing the cooling efficiency of the second and third stage battery modules.
In addition to the above configuration, the battery cooling structure of the present invention can be used in combination with other flow control members and structures such as a flow control plate (34) on the downstream side of the assembled battery. In particular, in order to increase the cooling efficiency of the battery module on the downstream side, it is preferable to use such another cooling structure in combination.

The purpose and application for which the assembled battery is used are not limited to those for automobiles. For example, a secondary battery is used for the purpose of leveling generated power in a wind power generator or a solar battery power generator. The present invention can be utilized for cooling a battery pack used for a wide range of applications.

INDUSTRIAL APPLICABILITY The present invention can be used for cooling large-capacity assembled batteries used in electric vehicles, hybrid vehicles, power generators, etc., and the batteries constituting the assembled batteries are uniformly cooled to effectively improve the performance of the batteries. The industrial utility value is high.

DESCRIPTION OF SYMBOLS 1 Battery case 11 Cooling air inlet 12 Cooling air outlet 13 Flow control plate 131 Unit rectifier plate 132a First through hole 132b Second through hole 2 Battery module 33 Flow control plate 331 Unit rectifier plate 332a First through hole 332b Second Through hole 34 Downstream flow control plate

Claims (5)

A battery case in which a plurality of battery modules are arranged in a plurality of rows is stored in a battery case,
Cooling air is introduced into the battery case from the cooling air inlet provided in the battery case, the battery module is cooled by the cooling air, and the cooling air is discharged outside the battery case from the cooling air outlet provided in the battery case. A battery cooling structure,
Inside the battery case, a flow control plate that divides the inside of the battery case into a downstream side and an upstream side is provided in an area upstream of the battery modules in the most upstream row,
The flow control plate is configured by continuously connecting unit rectifying plates extending in the battery length direction, and the flow control plate is provided with through holes that communicate the flow upstream side and the downstream side with each other,
The unit rectifier plate is provided in a bowl-like shape so as to cover a part of the upstream surface of the battery module at a predetermined interval with respect to each of the battery modules in the uppermost stream.
The unit rectifying plate is provided with a first through hole for introducing cooling air into each uppermost stream battery module,
The portions where the end portions of the unit rectifying plates that are continuously provided are adjacent to each other are defined as second through holes,
The second through hole is provided in a space between the most upstream battery modules adjacent to each other, and the cooling air introduced from the second through hole is prevented from hitting the uppermost battery module. Battery cooling structure characterized. 2. The battery cooling structure according to claim 1, wherein the second through-hole is configured to open between adjacent side portions of the most upstream battery module. 3. The battery cooling structure according to claim 1, wherein the battery module has a columnar shape, and the unit rectifying plate is formed in a circular arc shape in cross section. 4. The battery cooling structure according to claim 1, wherein the cooling air introduced from the second through hole is sent toward the battery modules in the second row. 5. Battery cooling structure according to any one of claims 1 to 4 cell module is characterized in that it is arranged in a zigzag pattern.