JP2006278140A - Battery pack - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To uniformly cool a plurality of battery modules housed in a holder case by reducing temperature difference between them. <P>SOLUTION: The battery pack houses the plurality of battery modules 1 in a holder case 2. The holder case constitutes a housing chamber 10 by a flow-in side plate 6 having a flow-in port 4, an exhaust side plate 7 having an exhaust pore 5, a first plate 8 jointing a first side edge of the exhaust side plate 7 and the flow-in side plate 6, and a second plate 9 jointing a second side edge, and the battery modules 1 are housed in the housing chamber in a plurality of stages and rows. Volume of cooling air flowing from the flow-in port to the holder case 2 at the first plate 8 side is made larger than that at the second plate 9 side, and the volume of cooling air flowing from the exhaust port 5 to outside of the holder case 2 at the second plate 9 side is made larger than that at the first plate 8 side. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an assembled battery in which a large number of unit cells are connected in series or in parallel, and more particularly to an assembled battery used in a power supply device that mainly drives a motor that drives an automobile.

  An electric vehicle such as an electric vehicle or a hybrid car that is driven by both an internal combustion engine and a motor uses an assembled battery in which a number of unit cells are connected as a power source for supplying electric power to the driving motor.

  The assembled battery used for this type of application has a high output voltage to supply power to a high-power motor. For this reason, many unit cells are connected in series and stored in the holder. For example, an assembled battery mounted on a hybrid car currently on the market has hundreds of unit cells connected in series to increase the output voltage to several hundred volts. In this assembled battery, 5 to 6 unit cells are connected in series to form a battery module, and a large number of battery modules are housed in a holder case.

  An assembled battery mounted on an electric vehicle such as a hybrid car discharges a large current when the vehicle suddenly accelerates, accelerates the motor, and is charged with a large current by a regenerative brake when decelerating or going down a hill. . For this reason, the battery may become very hot. In addition, since the battery is used in a hot environment in summer, the battery temperature becomes even higher. Therefore, it is important for the assembled battery in which a large number of batteries are stored in the holder case to cool each of the built-in batteries efficiently and uniformly. Various adverse effects occur when there is a temperature difference between the batteries to be cooled. For example, a battery with a high temperature deteriorates and the actual charge capacity that can be fully charged is reduced. When batteries having a substantially reduced charge capacity are connected in series and charged and discharged with the same current, overcharge or overdischarge tends to occur. This is because the capacity that can be fully charged and the capacity that can be completely discharged are small. The characteristics of the battery are remarkably deteriorated due to overcharge and overdischarge. For this reason, a battery having a substantially reduced charge capacity deteriorates at an accelerated rate. In particular, when the temperature of the battery becomes high, the deterioration of the battery is further increased. For this reason, it is important for the assembled battery in which a large number of batteries are stored in the holder case to cool all the batteries uniformly so as not to cause temperature unevenness.

Various structures have been developed to achieve this. (See Patent Documents 1 to 5)
JP 11-329518 A JP-A-11-180168 JP 2001-167806 A JP 2001-256940 A JP 2002-141114 A

  In the assembled battery described in Patent Document 1, a plurality of battery modules are arranged in multiple stages on a holder case with a predetermined gap therebetween. In this assembled battery, a plurality of battery modules are arranged in a plurality of stages in a vertical orientation in a horizontal posture, and further arranged in a plurality of rows, and cooling air is forced between each row to cool the battery modules. Yes. In this cooling structure, the cooling efficiency of the battery module on the downstream side is lower than that on the upstream side. In order to eliminate this drawback, a turbulence promoting body such as a dummy battery unit is provided at the uppermost position of the holder case, and the battery module at the upstream position is arranged by disturbing the flow of cooling air introduced into the holder case. Cools efficiently. Further, the holder case is provided with an auxiliary cooling air intake for taking in the cooling air in the middle of the cooling air flow path, so that the battery cooling efficiency on the downstream side is enhanced.

  This assembled battery can improve the cooling effect of the battery module on the downstream side by turbulent flow or cooling air that flows in the middle. However, this structure does not allow all battery modules to be cooled to a uniform temperature. In particular, a large number of battery modules cannot be accommodated in the holder case to reduce the temperature difference between the battery modules.

  In the assembled battery of Patent Documents 2 and 3, a plurality of battery modules are integrated into a rectangular parallelepiped shape and accommodated in an outer case as a battery block. The battery block is disposed so as to be inclined with respect to the bottom surface and the top surface of the outer case. Inside the outer case, a cross-flow type impeller is rotatably disposed along the entire side portion close to the bottom surface of the battery block, and sucked from an intake port provided below the impeller. Cooling air flows into the space above the battery block, passes between the battery modules of the battery block, and cools each battery module. The cooling air is discharged from an exhaust port provided in the lower part of the battery housing case on the far side of the impeller.

  In this assembled battery, in order to blow cooling air uniformly between the battery modules, the supply side air duct is made narrower toward the downstream side, and the discharge side air duct is made wider on the downstream side. ing. In this structure, even if the battery modules can be stored in a single stage in the outer case and uniformly cooled, the battery modules can be stored in multiple stages in the outer case and not all the battery modules can be cooled uniformly. In addition, a long sirocco fan is required to forcibly blow cooling air uniformly to all battery modules. In particular, when the number of battery modules stored in one stage increases, the sirocco fan becomes even longer. Although the sirocco fan has the feature that the operation sound can be made quieter, the structure is more complicated and the manufacturing cost is higher than that of the axial fan, and the efficiency of forced cooling air is low. For this reason, there is a drawback that the power consumption of the motor that drives the sirocco fan is increased.

  Further, the assembled batteries of Patent Documents 4 and 5 were previously developed by the present applicant. In this assembled battery, battery modules in which a plurality of batteries are connected in a rod shape are arranged in parallel and stored in a holder case. Further, a plurality of holder cases are arranged and stored in the outer case. Each holder case has a vent hole for cooling a plurality of battery modules housed therein. The ventilation opening is extended and opened in the direction parallel to the battery module. Furthermore, in order to cool the unit cell of a battery module uniformly, the ventilation hole is small at the end part of the holder case, and is greatly opened at the center part. This assembled battery can uniformly cool the unit cells of the elongated battery module. However, there is a drawback that the cooling efficiency of the battery module is low.

  The present invention has been developed for the purpose of solving this drawback. An important object of the present invention is to provide an assembled battery that can cool a battery module uniformly by reducing a temperature difference between a plurality of battery modules housed in a holder case.

The assembled battery of the present invention has the following configuration in order to achieve the above-described object.
The assembled battery includes a battery module 1 that connects a plurality of unit cells, and a holder case 2 that stores the plurality of battery modules 1 in a parallel posture. The holder case 2 has an inlet 4 and an outlet 5 for blowing and cooling cooling air to the battery module 1 accommodated therein. The assembled battery cools the battery module 1 with the cooling air flowing into the holder case 2 from the inlet 4, and discharges the cooling air that has cooled the battery module 1 from the outlet 5. The holder case 2 includes an inflow side plate 6 that opens the inflow port 4, a discharge side plate 7 that opens on the surface facing the inflow side plate 6 and opens the discharge port 5, and the discharge side plate 7 and a first plate 8 connected to the first side edge of the inflow side plate 6, and a second plate 9 connected to the discharge side plate 7 and the second side edge of the inflow side plate 6. ing. The discharge side plate 7, the inflow side plate 6, the first plate 8, and the second plate 9 constitute a storage chamber 10 for the battery module 1. Inside the storage chamber 10, the inflow side plate 6 to the discharge side plate 7. The battery modules 1 are housed in a plurality of stages separated in the direction to provide vertical gaps 11 between the battery modules 1, and the battery modules 1 are housed in a plurality of rows separated from the first plate 8 toward the second plate 9. A lateral gap 12 is provided between the battery modules 1. The inlet 4 has an opening area on the first plate 8 side larger than the opening area on the second plate 9 side, and the outlet 5 has an opening area on the second plate 9 side larger than the opening area on the first plate 8 side. It is also bigger. The amount of cooling air flowing into the holder case 2 from the inlet 4 is larger on the first plate 8 side than the second plate 9 side, and the amount of cooling air discharged from the outlet 5 to the outside of the holder case 2 is The second plate 9 side is larger than the first plate 8 side. In the battery pack, the cooling air flowing in from the inlet 4 passes through the vertical gap 11 and the horizontal gap 12 to cool the battery module 1, and the cooling air that has passed through the vertical gap 11 branches into the horizontal gap 12. The battery module 1 is cooled by flowing.

  In the assembled battery of the present invention, the battery module 1 can be arranged in the holder case 2 such that the vertical gap 11 or the horizontal gap 12 of the battery module 1 is not uniform.

  In the assembled battery of the present invention, the battery modules 1 are accommodated in the holder case 2 in two rows, and the second row of battery modules 1 arranged on the second plate 9 side are connected from the discharge side plate 7 to the inflow side plate. As approaching 6, it is arranged closer to the second plate 9, and the lateral gap 12 between the battery modules 1 in the first row and the battery modules 1 in the second row approaches the inflow side plate 6. Can be wide.

  Further, in the assembled battery of the present invention, the first row of battery modules 1 are arranged in parallel or substantially in parallel with the inner surface of the first plate 8, and the second row of battery modules 1 is arranged from the discharge side plate 7 to the inflow side plate 6. It can arrange so that it may leave | separate from the 1st plate 8 as it approaches.

  In the assembled battery of the present invention, the inflow side plate 6 can open the inflow port 4 in the middle and the first plate 8 side. Further, in the assembled battery of the present invention, the discharge side plate 7 can open the discharge ports 5 in the middle and the second plate 9 side.

  The assembled battery of the present invention can be arranged such that the battery module 1 approaching the inflow side plate 6 is closer to the second plate 9 than the battery module 1 approaching the discharge side plate 7.

  In the assembled battery of the present invention, the airflow death region generated downstream of the battery module 1 on the inflow side plate 6 side approaches the second plate 9 side of the battery module 1 disposed on the discharge side plate 7 side. Can be arranged.

  In the assembled battery of the present invention, a plurality of holder cases 2 are accommodated in the outer case 3 side by side in such a manner that the inflow side plate 6 is positioned on the same plane and the discharge side plate 7 is also positioned on the same plane. Can do. In this assembled battery, an inflow side air duct 13 and a discharge side air duct 14 are provided between the outer case 3 and the holder case 2, and the inflow side air duct 13 is connected to each holder case via the inlet 4. 2, the discharge side air duct 14 can be connected to the inside of each holder case 2 through the discharge port 5. In this assembled battery, the cooling air in the inflow side air duct 13 is introduced into the holder case 2 through the inflow port 4, and the cooling air in the holder case 2 is in the exhaust side air duct 14 through the discharge port 5. So that the battery module 1 in the holder case 2 is cooled.

  The assembled battery of the present invention has an advantage that the battery module can be cooled uniformly by reducing the temperature difference between the plurality of battery modules stored in the holder case. That is, the assembled battery of the present invention is connected to the inflow side plate opening the inflow port, the discharge side plate opening the discharge port, and the first side edge of the discharge side plate and the inflow side plate. Batteries in a plurality of rows and a plurality of rows inside a holder case that forms a storage chamber with the first plate and the second plate connected to the second side edge of the discharge side plate and the inflow side plate The module is housed, and the inlet has an opening area on the first plate side larger than the opening area on the second plate side, and the amount of cooling air flowing from the inlet to the holder case is larger than that on the second plate side. Is increased on the first plate side, and the discharge port has a larger opening area on the second plate side than the opening area on the first plate side, so that the amount of cooling air discharged from the discharge port to the outside of the holder case is increased. Than one plate side Is because as increases in second plate side. In the assembled battery having this structure, the cooling air that is largely flowed in from the first plate side and discharged from the second plate side is arranged in a plurality of rows and vertical gaps provided between the battery modules stored in a plurality of stages. Since the battery module is cooled by passing through the lateral gap provided between the battery modules to be stored, the cooling air flows on both sides of the battery module, and the heat exchange efficiency between the cooling air and the battery module is increased. The module can be cooled efficiently.

  Embodiments of the present invention will be described below with reference to the drawings. However, the example shown below illustrates the assembled battery for embodying the technical idea of the present invention, and the present invention does not specify the assembled battery as follows.

  Further, in this specification, in order to facilitate understanding of the scope of claims, numbers corresponding to the members shown in the examples are indicated in the “claims” and “means for solving problems” sections. It is added to the members. However, the members shown in the claims are not limited to the members in the embodiments.

  In the assembled battery shown in FIGS. 1 to 3, a plurality of holder cases 2 are linearly connected and stored in an outer case 3. The holder case 2 houses a plurality of battery modules 1. The battery module 1 is formed by connecting a plurality of unit cells in series and connecting them in a straight line. The plurality of battery modules 1 housed in each holder case 2 are connected to each other in series. However, the battery module 1 of the holder case 2 can be connected in series and in parallel.

  The assembled battery shown in the figure includes an inflow side air duct 13 that supplies cooling air to the holder case 2 between the outer case 3 and the holder case 2, and a discharge side air duct that exhausts the cooling air in the holder case 2. 14 is provided. The assembled battery cools the battery module 1 when it passes through the inside of the holder case 2 by flowing cooling air from the inflow side air duct 13 to the inside of the holder case 2 to the exhaust side air duct 14. The assembled battery of FIGS. 2 and 3 has an inflow side air duct 13 below the holder case 2 and an exhaust side air duct 14 above the holder case 2. This assembled battery can smoothly flow cooling air through the holder case 2. This is because the cooling air that rises lightly when heated is sent from the bottom to the top. That is, the cooling air flows in the direction of natural convection. However, the battery pack can also cool the battery module by forcibly blowing cooling air from the top to the bottom. Furthermore, the assembled battery of the figure arrange | positions the electronic circuit 15 which is a control circuit which controls charging / discharging of the battery module 1 in the ventilation duct 14 by the side of discharge. This assembled battery forcibly cools the electronic circuit 15 with the cooling air passing through the discharge-side air duct 14.

  As shown in FIGS. 1 to 3, the battery pack in which a plurality of holder cases 2 are stored side by side in the outer case 3 can control the output voltage by changing the number of holder cases 2 stored in the outer case 3. This is because the output voltage can be increased by increasing the number of holder cases 2 housed in the outer case 3 and increasing the number of batteries connected in series. However, in the assembled battery of the present invention, it is not always necessary to connect a plurality of holder cases and store them in the outer case. For example, as shown in FIG. 4, the holder case 2 is partitioned into a plurality of storage chambers 10 by partition walls 16. Thus, the battery modules 1 can be stored in each storage chamber 10 in a plurality of rows and a plurality of stages.

  2 and 3, the air blowing duct 13 on the inflow side is gradually narrowed in the flow direction of the cooling air, and the air blowing duct 14 on the discharge side is gradually widened in the flow direction of the cooling air. ing. This assembled battery can be uniformly cooled by blowing cooling air uniformly to each holder case 2.

  The outer case 3 of the assembled battery in FIG. 1 is a metal that connects the battery module 1 of the holder case 2 in series with a lower case 3A that fixes a plurality of holder cases 2 side by side and the holder case 2 at both ends. An end plate 17 containing a bus bar (not shown), which is a plate, and an upper case 3B connected to the frame 3b of the lower case 3A are provided.

  The lower case 3A is a frame 3b for fixing the holder case 2 side by side. This lower case 3A is provided with ridges 3a along both sides. Both ends of the holder case 2 are fixed to the protruding ridges 3a on both sides, and an air duct is provided between the holder case 2 and the lower case 3A. Lower case 3A can adjust the up-and-down width of an air duct with the height of convex 3a. In the assembled battery in which the inflow-side air duct 13 is provided between the holder case 2 and the lower case 3A, the height of the ridge 3a is gradually lowered in the direction in which the cooling air flows. This lower case 3A can narrow the inflow side air duct 13 in the direction in which the cooling air flows.

  The end plate 17 is formed of an insulating material such as plastic and connects bus bars fixed to electrode terminals provided at both ends of the battery module 1 at a fixed position. The end plate 17 is fixed to a fixed position of the holder case 2 by fixing the bus bar to the battery module 1 with screws.

  The upper case 3 </ b> B is a cover that covers the upper surface and both sides of the holder case 2. In the upper case 3B, side walls 3d covering both side surfaces of the holder case 2 are connected to both sides of the top plate 3c covering the upper surface of the holder case 2. The upper case 3B is connected to the lower case 3A by connecting the lower end of the side wall 3d to the frame 3b of the lower case 3A. The upper case 3B is provided with an air duct between the top plate 3c and the holder case 2. As shown in FIG. 3, the battery pack using the air duct as the discharge-side air duct 14 gradually increases the distance between the top plate 3 c and the holder case 2 in the direction in which the cooling air flows.

  As shown in FIG. 5, the holder case 2 houses a plurality of battery modules 1 arranged in a parallel posture. The battery module 1 has a plurality of unit cells connected in a straight line in series. In the battery module 1, for example, 5 to 6 unit cells are linearly connected. However, the battery module can connect four or less, or seven or more unit cells. The unit cell is a nickel metal hydride battery. However, the unit cell may be another secondary battery such as a lithium ion secondary battery or a nickel cadmium battery. In the illustrated battery module 1, cylindrical batteries are linearly connected to form a columnar shape, but the battery module may be formed in a polygonal column shape such as a square column.

  A cross-sectional view of the holder case 2 shown in FIG. 5 is shown in FIG. The holder case 2 stores the battery modules 1 in two rows and three stages, and stores six battery modules 1. The holder case 2 shown in FIGS. 7 to 9 stores battery modules 1 in two rows and two stages, and stores four battery modules 1.

  The holder case 2 shown in these figures has an inlet 4 and an outlet 5 for blowing cooling air to the battery module 1 stored therein to cool it, and the holder case 2 is opened from the inlet 4. The battery module 1 is cooled by the cooling air that flows into the battery 1, and the cooling air that has cooled the battery module 1 is discharged from the outlet 5.

Further, the holder case 2 includes an inflow side plate 6 that opens the inflow port 4, a discharge side plate 7 that opens a discharge port 5 located on a surface facing the inflow side plate 6, and the discharge side plate. 7 and a first plate 8 connected to the first side edge of the inflow side plate 6, and a second plate 9 connected to the discharge side plate 7 and the second side edge of the inflow side plate 6. ing. Since the holder case 2 shown in the figure blows cooling air from the bottom to the top, the inflow side plate 6 is a bottom plate and the discharge side plate 7 is a top plate. Further, the side plate located on the cooling air supply side, that is, the right side plate in the figure is the first plate 8, the side plate located on the cooling air discharge side, and the left side plate in the figure is the second plate 9. The holder case 2 includes a discharge plate 7 as a bottom plate, an inflow plate 6 as a top plate, a first plate 8 as a right side plate, and a second plate 9 as a left side plate. The chamber 10 is configured, and the battery module 1 is stored in the storage chamber 10. Since the storage chamber 10 is opened to the outside by the inlet 4 and the outlet 5, it is a space that is closed but not sealed.
As shown in FIG. 4, in the holder case 2 partitioned into a plurality of storage chambers 10 by the partition wall 16, each storage chamber 10 is divided into a discharge plate 7 on the bottom plate, an inflow side plate 6 on the top plate, It is comprised with the partition 16 and 16 located in right and left. Accordingly, when focusing on one storage chamber 10, the partition located on the cooling air supply side, that is, the partition located on the right side in the figure corresponds to the first plate, and the partition located on the cooling air discharge side, ie, the figure. The partition located on the left side corresponds to the second plate.

  The battery module 1 accommodates the battery module 1 in a plurality of stages in the holder case 2 in the direction from the inflow side plate 6 to the discharge side plate 7, in the vertical direction in the figure. A vertical gap 11 is provided to pass through. The holder case 2 shown in FIGS. 5 and 6 accommodates the battery module 1 in three stages separated vertically, and the holder case 2 shown in FIGS. 7 to 9 accommodates the battery module 1 in two stages up and down. A vertical gap 11 is provided between the modules 1. Further, the holder case 2 stores the battery modules 1 in a plurality of rows separated from the first plate 8 in the direction of the second plate 9, and a lateral gap 12 through which the cooling air passes is provided between the battery modules 1. Yes. The holder case 2 shown in these figures accommodates the battery modules 1 in two rows, and a lateral gap 12 is provided between the battery modules 1.

  In order to cool each battery module 1 uniformly, the holder case 2 opens the inlet 4 only at the center of the inflow side plate 6 as shown in FIG. Do not open the discharge port 5 only.

  As shown in FIG. 9, the holder case 2 opens the inlet 4 only on the first plate 8 side, or, as shown in FIGS. 6 to 8, in two places on the first plate 8 side and the central portion. The inlet 4 is opened so that the opening area on the first plate 8 side is larger than the opening area on the second plate 9 side. By the way, in this specification, the opening area on the first plate side means the total opening area of the inflow opening opened to the first plate side rather than the center of the inflow side plate, and the opening on the second plate side. An area means the total opening area of the inflow port opened to the 2nd plate side rather than the center of the inflow side plate.

  In the holder case 2 having the above structure, the amount of cooling air flowing from the inlet 4 into the holder case 2 is larger on the first plate 8 side than on the second plate 9 side. This is because as the opening area of the inlet 4 increases, the amount of cooling air flowing into the holder case 2 increases. Since the holder case 2 of FIG. 9 flows in cooling air only from the inlet 4 on the first plate 8 side and does not flow from the second plate 9 side, the amount of air flowing into the holder case 2 is the second plate. More on the first plate 8 side than on the 9 side. Further, in the holder case 2 of FIGS. 6 to 8, the cooling air flows from both the central portion and the first plate 8 side, but does not flow from the second plate 9 side, so that it flows into the holder case 2. The amount of cooling air to be increased increases on the first plate 8 side. Furthermore, although not shown in the drawings, the holder case may be configured such that an inflow port smaller than the first plate side is opened on the second plate side of the inflow side plate so that the air volume is increased on the first plate side than on the second plate side. it can. Furthermore, although not shown, one or a plurality of inflow ports may be opened in the middle of the inflow side plate so that the flow rate of the cooling air is increased on the first plate side than on the second plate side.

  Furthermore, as shown in FIG. 9, the holder case 2 opens the discharge port 5 only on the second plate 9 side, or, as shown in FIGS. The discharge port 5 is opened at a place so that the opening area on the second plate 9 side is larger than the opening area on the first plate 8 side. However, in this specification, the opening area on the second plate side means the total opening area of the discharge port opened on the second plate side rather than the center of the discharge side plate, and the opening on the first plate side An area means the total opening area of the discharge port opened to the 1st plate side rather than the center of the discharge side plate.

  In the holder case 2 having the above structure, the amount of cooling air discharged from the discharge port 5 to the outside of the holder case 2 is larger on the second plate 9 side than on the first plate 8 side. This is because as the opening area of the discharge port 5 increases, the amount of cooling air discharged to the holder case 2 increases. Since the holder case 2 of FIG. 9 discharges cooling air only from the discharge port 5 on the second plate 9 side and not from the first plate 8 side, the amount of air discharged from the holder case 2 is the first plate. More on the second plate 9 side than on the 8 side. 6 to 8, the cooling air is discharged from both the central portion and the second plate 9 side, but is not discharged from the first plate 8 side. Therefore, the holder case 2 is discharged from the holder case 2. The amount of cooling air to be increased increases on the second plate 9 side. Furthermore, although not shown in the drawings, the holder case may open a discharge port smaller than the second plate side on the first plate side of the discharge side plate so that the air volume is increased on the second plate side than on the first plate side. it can. Further, although not shown, one or a plurality of discharge ports can be opened in the middle of the discharge side plate so that the flow rate of the cooling air can be increased on the second plate side than on the first plate side.

  The holder case 2 of the assembled battery according to the present invention increases the amount of cooling air flowing from the inlet 4 of the inflow side plate 6 on the first plate 8 side than the second plate 9 side, and the discharge side plate 7 is increased on the second plate 9 side than on the first plate 8 side. The cooling air flowing into the holder case 2 in this state does not pass between the rows of the battery modules 1 unlike the conventional holder case 2 shown in FIG. The cooling air passing through the horizontal gaps 12 between the rows of the battery modules 1 does not flow in the path indicated by the chain line in FIG. 10, and the heat exchange efficiency between the cooling air and the battery modules 1 is low, and the cooling air is efficient. Can't cool well. This is because the cooling air does not flow along a large area of the surface of the battery module 1. As shown in FIGS. 6 to 9, the assembled battery of the present invention has many inflow ports 4 on the first plate 8 side and many discharge ports 5 on the second plate 9 side. It flows on both sides of the battery module 1, heat exchange efficiency between the cooling air and the battery module 1 is increased, and each battery module 1 can be efficiently cooled.

  In particular, the holder case 2 shown in FIGS. 6 to 8 can efficiently cool the battery module 1 on the upper first plate 8 side and the battery module 1 on the lower second plate 9 side with high heat exchange efficiency. . It can flow cooling air to both sides of the battery module 1 in a well-balanced manner with the inlet 4 opening at the center of the inflow side plate 6 and the outlet 5 opening at the center of the discharge side plate 7. Because. That is, with the inlet 4 at the center of the inflow side plate 6, as shown by the arrow A in the figure, the cooling air flowing between the corner portion of the inflow side plate 6 and the second plate 9 and the battery module 1 The air volume can be controlled, and further, with the discharge port 5 at the center of the discharge side plate 7, as shown by the arrow B in the figure, between the corner part of the discharge side plate 7 and the first plate 8 and the battery module 1. This is because it is possible to control the air volume of the cooling air flowing through.

  Furthermore, the holder case 2 of FIGS. 6 and 7 allows the lower battery module 1 approaching the inflow side plate 6 to be closer to the second plate 9 than the upper battery module 1 approaching the discharge side plate 7. It is arranged. The holder case 2 can cool the battery module 1 in a well-balanced manner with high heat exchange efficiency by reducing the influence of the dead water area 18 which is an airflow death area formed downstream of the battery module 1. The “dead water area” is an area that is generated downstream of the cooling medium when it collides with an object so that the cooling medium does not flow smoothly and stagnates, as is also used in a heat exchange effector. When the cooling air flows so as to cross the battery module, a dead water area 18 that becomes a stagnation of the cooling air is formed on the downstream side of the battery module. Since the dead water area 18 is an area where the cooling air does not flow smoothly, the heat exchange efficiency of the battery module is lowered and cannot be cooled efficiently. 6 and 7 shifts the lower battery module 1 arranged on the inflow side plate 6 side to the second plate 9 side than the upper battery module 1 arranged on the discharge side plate 7 side. It is arranged. The holder case 2 moves a dead water area 18 generated downstream of the lower battery module 1 to the second plate 9 side of the battery module 1 arranged in the upper stage. For this reason, this holder case 2 does not decrease the heat exchange efficiency of the upper battery module 1 due to the influence of the dead water area 18 of the lower battery module 1, and all the battery modules 1 can be efficiently exchanged with high heat exchange efficiency. Cool well in a balanced manner.

  Further, in the holder case 2 of FIG. 6, the first row of battery modules 1 arranged on the right side in the drawing is substantially parallel to the first plate 8, and the second row of battery modules 1 arranged on the left side is connected to the inflow side plate 6. It arrange | positions so that it may approach the 2nd plate 9 gradually toward this. The holder case 2 is an ideal arrangement that can eliminate the influence of the dead water area 18 generated downstream of the battery module 1 and can cool all the battery modules 1 uniformly with high heat exchange efficiency in a balanced manner. The battery modules 1 in the first row and the second row have different conditions for the cooling air flowing through the vertical gap 11. The battery modules 1 in the second row are closed on the left side with the second plate 9, whereas the battery modules 1 in the first row have the vertical gaps 11 of the battery modules 1 in the second row on the left side. It is. The flow velocity of the cooling air passing through the vertical gaps 11 of the first row of battery modules 1 having the vertical gaps 11 of the second row of battery modules 1 on the left side is increased in the horizontal vector in the figure. This is because the cooling air that has passed through the vertical gaps 11 of the battery modules 1 in the first row passes through the vertical gaps 11 of the battery modules 1 in the second row. For this reason, the dead water area 18 generated downstream of the battery modules 1 in the first row has a strong tendency that the rear end faces the vertical gap 11 in the second row. On the other hand, the flow velocity of the cooling air that has passed through the vertical gaps 11 of the battery modules 1 in the second row is smaller in the horizontal vector because the left side of the vertical gap 11 is closed by the second plate 9. For this reason, the dead water area 18 generated downstream of the battery modules 1 in the second row has a strong tendency to face upward where the rear end is on the discharge side plate 7 side. In the holder case 2 of FIG. 6, in order to reduce the influence of the dead water area 18, the battery modules 1 in the second row are directed toward the inflow side plate 6 side, that is, the lower battery modules 1 are directed to the second plate 9 side. Move closer. This is because the rear end of the dead water area 18 faces upward. On the other hand, the battery modules 1 in the first row are arranged in parallel with the first plate 8 to eliminate the influence of the dead water area 18. Since the dead water area 18 generated downstream of the battery modules 1 in the first row is more lateral than the dead water area 18 of the battery modules 1 in the second row, the dead water area 18 is disposed in parallel with the first plate 8. This is because the influence can be eliminated.

  The holder case 2 has a lower inflow side, as shown by a one-dot chain line in FIG. 6, where the center lines a and b passing through the centers of the battery modules 1 in the first row and the second row are not parallel to each other. The battery module 1 is arranged so as to be wide on the plate 6 side and narrow on the upper discharge side plate 7 side, and the inclination angle of the center line b of the battery module 1 on the second plate 9 side is set to the first plate 8 side. More than the inclination angle of the center line a of the battery module 1, more precisely, the center line b of the battery module 1 on the second plate 9 side approaches the second plate 9 from the discharge side plate 7 toward the inflow side plate 6. By inclining in the direction to be generated, all the battery modules 1 can be uniformly cooled with high heat exchange efficiency. However, in this specification, the inclination angle of the center line means an angle formed by the center line and the first plate or the second plate.

  In the holder case 2 of FIG. 6, the center line a of the battery module 1 on the first plate 8 side is parallel to the first plate 8, but the center line a is not necessarily parallel to the first plate. For example, the second plate may be inclined toward the inflow side plate from the discharge side plate, or may be inclined in the opposite direction. However, the inclination angle of the center line a of the battery module on the first plate side is made smaller than the inclination angle of the center line b of the battery module on the second plate side. This is because, as described above, the direction of the dead water area of the battery module on the first plate side is different from that of the battery module on the second plate side.

  In the illustrated holder case 2, the vertical gaps 11 of the battery modules 1 arranged above and below are substantially the same, but the vertical gap can be changed to control the balance of the cooling air flowing through the battery modules. For example, widening the vertical gap between battery modules that tend to increase in temperature increases the amount of cooling air, or narrows the vertical gap to increase the wind speed to control the heat exchange efficiency of the battery module. Can do. In addition, the distance between the battery module and the inflow side plate, the discharge side plate, the first plate, and the second plate is adjusted to control the flow rate and flow rate of the cooling air flowing between the battery module and these plates. Thus, the heat exchange efficiency of the battery module can be adjusted.

  The holder case 2 shown in FIGS. 6 to 9 can increase the heat exchange efficiency between the battery module 1 and the cooling air as compared with the holder case 2 shown in FIG. In particular, the holder case 2 shown in FIG. 6 is more excellent in heat exchange efficiency than the holder case 2 shown in FIG. 11, and is characterized in that all the battery modules 1 can be cooled uniformly. As shown in FIG. 9, the holder case 2 shown in FIG. 11 has an inlet 4 on the first plate 8 side of the inflow side plate 6 and an outlet 5 on the second plate 9 side of the outlet side plate 7, In the same manner as in FIG. 6, two rows and three stages of battery modules 1 are accommodated so that the center lines a and b of the battery modules 1 are parallel to the first plate 8 and the second plate 9. . For example, the holder case 2 shown in FIG. 6 has extremely excellent characteristics that can reduce the temperature difference of the battery module 1 to 40% or less in a specific usage environment as compared with the holder case 2 shown in FIG. . In this assembled battery, eight holder cases 2 are arranged on the same surface as the outer case 3 as shown in FIGS. 1 to 3, 48 battery modules 1 are provided, and the air blowing duct 13 on the inflow side is shown in FIG. 3. It is the result of having tested by what narrowed the air duct 14 on the discharge side gradually and gradually widened.

It is a disassembled perspective view of the assembled battery concerning one Example of this invention. It is a schematic perspective view of the assembled battery concerning one Example of this invention. It is a vertical longitudinal cross-sectional view of the assembled battery concerning one Example of this invention. It is a vertical longitudinal cross-sectional view of the assembled battery concerning the other Example of this invention. It is a partial cross section perspective view of the holder case of the assembled battery shown in FIG. FIG. 6 is a vertical cross-sectional view of the holder case shown in FIG. 5. It is a vertical cross-sectional view which shows another example of a holder case. It is a vertical cross-sectional view which shows another example of a holder case. It is a vertical cross-sectional view which shows another example of a holder case. It is a vertical cross-sectional view showing an example of a conventional holder case. It is a vertical cross-sectional view which shows another example of a holder case.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Battery module 2 ... Holder case 3 ... Outer case 3A ... Lower case 3B ... Upper case
3a ... ridge 3b ... frame
3c ... Top plate 3d ... Side wall 4 ... Inlet 5 ... Discharge port 6 ... Inflow side plate 7 ... Discharge side plate 8 ... First plate 9 ... Second plate 10 ... Storage chamber 11 ... Vertical gap 12 ... Horizontal gap 13 ... Inflow Side air duct 14 ... Discharge side air duct 15 ... Electronic circuit 16 ... Bulkhead 17 ... End plate 18 ... Dead water area

Claims (9)

A battery module (1) for connecting a plurality of unit cells, and a holder case (2) for storing a plurality of battery modules (1) arranged in a parallel posture, the holder case (2) being stored. The battery module (1) has an inlet (4) and an outlet (5) for cooling the battery module by blowing cooling air.
The battery module (1) is cooled by cooling air flowing into the holder case (2) from the inlet (4), and the cooling air that has cooled the battery module (1) is discharged from the outlet (5). In assembled batteries,
The holder case (2) has an inflow side plate (6) that opens the inflow port (4) and a discharge port that opens the discharge port (5) located on the surface facing the inflow side plate (6). Side plate (7), first plate (8) connected to the first side edge of discharge side plate (7) and inflow side plate (6), discharge side plate (7) and inflow side plate A second plate (9) connected to the second side edge of (6),
The discharge side plate (7), the inflow side plate (6), the first plate (8) and the second plate (9) constitute the storage chamber (10) of the battery module (1), and this storage chamber (10) The battery module (1) is housed in a plurality of stages at a distance from the inflow side plate (6) to the discharge side plate (7), and a vertical gap (11) is provided between the battery modules (1). The battery modules (1) are accommodated in a plurality of rows apart from the first plate (8) in the direction of the second plate (9), and a lateral gap (12) is provided between the battery modules (1).
The inlet (4) has an opening area on the first plate (8) side larger than an opening area on the second plate (9) side,
The outlet (5) has a larger opening area on the second plate (9) side than the opening area on the first plate (8) side,
The amount of cooling air flowing into the holder case (2) from the inlet (4) is larger on the first plate (8) side than on the second plate (9) side, and the holder case (2 ) So that the amount of cooling air discharged outside is larger on the second plate (9) side than on the first plate (8) side,
Cooling air flowing in from the inlet (4) passes through the vertical gap (11) and the horizontal gap (12) to cool the battery module (1), and the cooling air that has passed through the vertical gap (11) A battery pack that branches and flows into the gap (12) to cool the battery module (1).   The assembled battery according to claim 1, wherein the battery module (1) is arranged in the holder case (2) so that the vertical gap (11) or the horizontal gap (12) of the battery module (1) is not uniform. .   The battery module (1) is stored in two rows in the holder case (2), and the second row of battery modules (1) arranged on the second plate (9) side is connected to the discharge side plate (7). As approaching the inflow side plate (6) from the first row, the second plate (9) is arranged closer to the space between the first row of battery modules (1) and the second row of battery modules (1). The assembled battery according to claim 2, wherein the lateral gap (12) is made wider as it approaches the inflow side plate (6).   The first row of battery modules (1) are arranged in parallel or substantially parallel to the inner surface of the first plate (8), and the second row of battery modules (1) are arranged from the discharge side plate (7) to the inflow side plate (6). The assembled battery according to claim 3, wherein the battery pack is arranged so as to move away from the second plate (9) as it approaches.   The assembled battery according to claim 1, wherein the inflow side plate (6) has an inflow port (4) opened in the middle and the first plate (8) side.   The assembled battery according to claim 1 or 5, wherein the discharge side plate (7) has a discharge port (5) opened in the middle and the second plate (9) side.   The battery module (1) approaching the inflow side plate (6) is disposed closer to the second plate (9) than the battery module (1) approaching the discharge side plate (7). 1. The assembled battery described in 1.   The airflow death area generated downstream of the battery module (1) on the inflow side plate (6) side is located on the second plate (9) side of the battery module (1) disposed on the discharge side plate (7) side. The assembled battery according to claim 1, which is arranged so as to approach. A plurality of holder cases (2) are arranged adjacent to each other so as to position the inflow side plate (6) on the same plane and the discharge side plate (7) on the same plane. The inflow side air duct (13) and the exhaust side air duct (14) are provided between the outer case (3) and the holder case (2). It is connected to the inside of each holder case (2) through the inlet (4), and the discharge side air duct (14) is connected to the inside of each holder case (2) through the discharge port (5), Cooling air from the inlet duct (13) flows into the holder case (2) through the inflow port (4), and cooling air in the holder case (2) exhausts through the discharge port (5). The assembled battery according to claim 1, wherein the battery module (1) in the holder case (2) is cooled by being discharged to the air duct (14) on the side.

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