JP4437009B2 - Secondary battery unit - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
[0002]
[Prior art]
Generally, a secondary battery unit for an electric vehicle is configured by arranging a plurality of secondary batteries (cells or modules) vertically and horizontally in a case. Conventionally, in order to cool a battery unit in such a case, for example, a cold air introduction port for taking in air from a cooling fan is formed on the front surface of the case, and air is provided between each battery cell or module in the case. Generally, a configuration is known in which a secondary battery is arranged in such a manner that a flow path is formed, and a wind from a cooling fan flows laterally on the side of each secondary battery to cool each battery cell or module. (For example, refer to Patent Document 1).
[0003]
[Patent Document 1]
Japanese Patent Laid-Open No. 2000-294302
[Problems to be solved by the invention]
However, in the configuration in which the cooling air cools each secondary battery in order from the battery located on the windward side to the battery located on the leeward side, the temperature of the cooling air flowing in the case while cooling each secondary battery is As the temperature increases toward the leeward side, not only the batteries placed on the leeward side will be insufficiently cooled, but also the secondary battery will not be cooled because the cooling air does not strike each secondary battery well. In some cases, it was insufficient. In order to avoid this, if the output of the cooling fan is increased, the size of the entire apparatus may be increased.
[0005]
Then, an object of this invention is to provide the secondary battery unit which can cool efficiently the secondary battery cell or module accommodated in the case.
[0006]
[Means for Solving the Problems]
In order to achieve the above object, the secondary battery unit of the present invention is a secondary battery unit that houses a plurality of secondary batteries in a case in which an inlet for introducing cooling air and an outlet for discharging cooling air are formed. The secondary batteries are arranged, and conductive heat transfer members extending from the inside to the outside of the arranged secondary batteries are joined together to form a part of the wall surface. And formed between a main flow path communicating with the introduction port and the discharge port, at least one partition plate formed with a communication portion, and a wall surface of the case, and communicated with the introduction port and the discharge port. And at least one sub-flow channel, wherein the main flow channel and the sub-flow channel communicate with each other through the communication portion.
[0007]
The secondary battery unit of the present invention configured as described above has a wall surface of the main flow path formed by joining conductive heat transfer members extending from the inside to the outside of the main bodies of the arranged secondary batteries. Part. For example, when the heat transfer member is an electrode terminal of a battery, cooling air is applied to the electrode terminal to remove the heat generated inside the battery transferred to the electrode terminal and the Joule heat generated in the electrode terminal itself. However, in the case of the present invention, it is possible to configure a part of the wall surface of the main flow path by electrically connecting each of these electrode terminals, so that a separate part for applying cooling air to the electrode terminals is required. And not. Further, the secondary battery unit of the present invention has a sub-flow path formed by a partition plate that communicates with the introduction port and the discharge port and is formed with a communication portion, and is provided by the communication portion that is formed on the partition plate. Since the main flow channel and the sub flow channel communicate with each other, the cooling air can be introduced from the sub flow channel side to the main flow channel side through the communication portion, so that the temperature as it flows from the introduction port side to the discharge port side. The rise in the temperature of the cooling air in the main flow path can be suppressed. Thereby, it becomes possible to suppress the battery cooling imbalance between the upstream side and the downstream side.
[0008]
Further, the secondary battery unit of the present invention is a double bottom partition plate in which the partition plate mounts each secondary battery on the partition plate and forms a first subchannel between the bottom surface of the case. The communication portion of the double bottom partition plate may be a plurality of holes formed in the double bottom partition plate, or the double bottom partition plate may be, for example, a resin mesh, You may consist of net-like members, such as a wire mesh and punching metal.
[0009]
Further, in the secondary battery unit of the present invention, the communication part generates a shunt flow whose flow velocity is higher than the flow velocity of the cooling air flowing through the sub flow channel in a direction intersecting with the cooling air flowing through the main flow channel, The heat transfer member may be cooled by being supplied to gaps formed between the heat transfer members by being joined to each other and being applied to the heat transfer members.
[0010]
Further, in the secondary battery unit of the present invention, the partition plate may be a control circuit board including a control circuit that forms a second sub-flow channel with the upper surface of the case. The communication part of the circuit board may be a gap formed between the side surface of the case and the control circuit board.
[0011]
Further, the secondary battery unit of the present invention has a configuration in which the main flow channel and each sub flow channel are merged and then communicated with the discharge port, and a bus bar, a cable, a fuse, a relay, or a combination of these in the merged region. The part may be arranged.
[0012]
Furthermore, in the secondary battery unit of the present invention, the heat transfer member may be an electrode terminal of the secondary battery.
[0013]
The secondary battery unit of the present invention may have n + 1 cooling air flow paths, where n is the number of partition plates.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
Next, embodiments of the present invention will be described with reference to the drawings. In addition, the battery in each embodiment refers to a battery cell or a battery module.
(First embodiment)
FIG. 1 is a schematic side sectional view of a secondary battery unit mounted on an electric vehicle or a hybrid vehicle according to the present embodiment, and FIG. 2A is a schematic top sectional view of the secondary battery unit. Shown in (b). FIG. 3 is a schematic perspective view of a laminated battery mounted on the secondary battery unit of the present embodiment.
[0015]
The secondary battery unit 1 has a box-shaped case body 4 formed with an inlet 4a into which cooling air is introduced from the vehicle interior and an outlet 4b from which cooling air is discharged, with respect to the bottom surface 4c of the case body 4. A double bottom partition plate 3 in which a plurality of holes 9 arranged so as to have a double bottom is formed, and a control circuit board 2 supported by a column 14 provided on the double bottom partition plate 3. In addition, a plurality of batteries (cells or modules) 8 are arranged in a line on the double bottom partition plate 3 and can be stored. In the vicinity of the outlet 4b in the case body 4, bus bar cables 13 including a bus bar, a cable, a fuse, a relay, and the like are arranged.
[0016]
The inlet 4 a of the case body 4 is connected to the duct inlet 15 and communicates with the interior of the electric vehicle via the duct inlet 15. On the other hand, the outlet 4b is connected to the duct outlet 5 and communicates with a place that is at least always at a lower pressure than the cooling air exhausted from the exhaust blower 6 and has a low pulsation pressure, for example, a portion communicating with the outside of the vehicle or a trunk room portion. is doing.
[0017]
An exhaust blower 6 that exhausts cooling air is connected to the duct outlet 5. By suction of the exhaust blower 6, the cooling air is introduced into the case body 4 from the vehicle interior and discharged to the trunk or the outside.
[0018]
The battery 8 has a laminated electrode composed of a positive electrode side active electrode and a negative electrode side active electrode therein, and a metal such as aluminum so that a tab 7 which is an electrode terminal electrically connected to the laminated electrode extends. It has a structure sealed with a laminate sheet 16 formed by superimposing a film and a heat-fusible resin film. Tabs 7 extending from both sides of each battery 8 arranged in a row on the double bottom partition plate 3 are electrically connected to tabs 7 of other adjacent batteries 8. A portion of the main flow path 10 for flowing the cooling air 10a is formed between the left and right side surfaces 4d of the case body 4 by sequentially connecting the tabs 7 to form a wall surface. Further, by connecting the tabs 7 to each other, the cooling air can flow between the tabs 7 in the longitudinal direction of the case body 4, that is, from the double bottom partition plate 3 side toward the control circuit board 2 side. A possible tab gap 7a is formed. In addition, the main flow path 10 in this embodiment is the double bottom partition plate 3 and the control circuit board | substrate 2 including the area | region between the wall surface formed by the joined tab 7, and the side surfaces 4d of the case main body 4 right and left. It is a region sandwiched between and the flow path through which the cooling air 10a for directly cooling the main body of each battery 8 and the tab 7 flows. Further, in FIG. 1, the batteries 8 are shown as having battery body portions arranged in close contact with each other, but are arranged with a gap formed between the batteries so that cooling air flows.
[0019]
The double bottom partition plate 3 is provided so as to form a double bottom with a space between the bottom surface 4c, and thereby, a first sub-flow channel 11 through which the cooling air 11a flows is formed. As described above, since the plurality of holes 9 are formed in the double bottom partition plate 3, a part of the cooling air 11a flows into the tab gap 7a as the divided flow 11b, and further, the divided flow 11b flows into the main flow path 10. It can be made to merge with the cooling air 10a which flows.
[0020]
The size of the plurality of holes 9 formed in the double bottom partition plate 3 is, for example, a width a = L / 5, a length b = 1.2 t to a length L and a thickness t of the battery 8. By setting the flow rate to about 2.8 t, it is possible to generate the diverted flow 11b with an increased flow rate. In addition, the shape of the hole 9 is shown as an example of a rectangular shape with a corner R processed in FIG. 2A, but is not limited to this, and is a circular shape of about φ0.5t. In addition, an elliptical shape or the like may be used. The opening areas of the plurality of holes 9 do not have to be the same, and may differ depending on the place where they are formed. For example, the opening area of the hole 9 may be gradually increased toward the longitudinal direction of the case body 4, that is, the downstream side of the cooling air 12a, or vice versa. Alternatively, the opening area of the hole 9 may be different in the width direction of the case body 4.
[0021]
Moreover, in this embodiment, although the several hole 9 is formed in the matrix shape in the double bottom partition plate 3 as shown to Fig.2 (a), it is not limited to this, For example, zigzag It may be arranged. That is, the shape and arrangement of the holes 9 formed in the double bottom partition plate 3, the opening cross-sectional shape, the numerical aperture, and the like can be appropriately selected depending on the amount of heat generated by the battery 8, the number of the batteries 8 arranged, and the like.
[0022]
The control circuit board 2 is provided so as to be spaced from the upper surface 4 e in order to form a second sub-flow channel 12 for flowing cooling air between the control circuit board 2 and the upper surface 4 e of the case body 4. . As shown in FIG. 2 (b), the control circuit board 2 is formed so that the second sub-flow channel 12 can be formed, that is, the cooling air 12a flows from the inlet 4a side to the outlet 4b side. In order to flow out along the control circuit board 2, even if the area occupied by the control circuit 2a on the control circuit board 2 is small, the length of the board from the inlet 4a side to the outlet 4b side is increased so that the second The sub-flow channel 12 is formed. Further, since the width of the control circuit board 2 is narrower than the distance between the side surfaces 4d of the case body 4, a gap 2b is formed between the control circuit board 2 and the side surface 4d. Thus, as will be described later, the lower surface of the control circuit board 2 includes the case where the diversion flow 10b of the cooling air 10a flowing through the main flow path 10 or the diversion flow 11b of the cooling air 11a flowing through the first sub flow path 11 is combined. The cooling air 12a of the second subchannel 12 can be merged by wrapping from the side toward the upper surface. In addition, since the control circuit board 2 joins the diversion flow 10b and the diversion flow 11b to the cooling air 12a, the main flow path 10 and the second sub flow path 12 are provided in the area where the control circuit 2a of the control circuit board 2 is not provided. It may be a structure in which a hole for communicating is formed.
[0023]
As described above, in the secondary battery unit 1 of the present embodiment, the double bottom partition plate 3 including a region between the tab 7 having a wall shape and the side surface 4d of the case body 4 is roughly divided. And the control circuit board 2, the main flow path 10, the first sub-flow path 11 between the double bottom partition plate 3 and the bottom surface 4 c of the case body 4, and the control circuit board 2. Three flow paths of the second sub flow path 12 are formed between the upper surface 4 e of the case body 4 and the upper surface 4 e of the case body 4.
[0024]
Next, how the cooling air flows in the secondary battery unit 1 will be described. In the following description, the diverted flow 11b refers to the flow of the cooling air that is branched from the holes 9 formed in the double bottom partition plate 3 by the cooling air 11a flowing through the first sub-passage 11, and the diverted flow 10a. The term “cooling air 10 a that flows through the main flow path 10” mainly refers to the flow of cooling air that flows toward the control circuit board 2 and the second sub flow path 12.
[0025]
First, by being sucked by the exhaust blower 6, the air in the passenger compartment flows as cooling air from the duct inlet 15 communicating with the passenger compartment of the electric vehicle into the inlet 4a.
[0026]
Next, the cooling air flowing into the inlet 4a is, on the inlet 4a side, the cooling air 10a flowing through the main flow path 10 formed between the tab 7 and the left and right side surfaces 4d of the case body 4, and the double bottom partition plate The cooling air 11 a flowing through the first sub-flow channel 11 formed by 3 and the cooling air 12 a flowing through the second sub-flow channel 12 formed by the control circuit board 2 are roughly divided. That is, in the secondary battery unit 1 of the present embodiment, three flow paths are formed for two partition plates including the double bottom partition plate 3 and the control circuit board 2.
[0027]
Hereinafter, the cooling air 11a, the cooling air 10a, the cooling air 12a, and the flow on the lower side of the secondary battery unit 1 will be described in order.
[0028]
The cooling air 11 a flowing through the first sub-channel 11 passes through the holes 9 formed in the double bottom partition plate 3 while flowing through the first sub-channel 11, and the gaps between the batteries 8 and the tab gaps 7 a. The bus bar cables 13 arranged in the outlet 4b are cooled and discharged from the outlet 4b while branching into a branch flow 11b which flows into the cooling air 10a or merges with the cooling air 10a. The diversion flow 11b flowing upward between the gaps between the batteries 8 and the tab gap 7a flows while contacting the main body of the battery 8 and the tabs 7, and is generated inside the battery 8 and transferred to the surface of the battery 8. And it flows upwards while removing the heat transferred to the tab 7 and merges with the cooling air 12a. The temperature of the branch stream 11b flowing upward in the tab gap 7a increases as it goes upward. However, since the cooling air 10a flows through the outside of the tab 7, that is, the main flow path 10, the temperature increase is suppressed and the efficiency is increased. Thus, the battery 8 can be cooled. Further, since the flow rate of the diversion flow 11b is increased by restricting the flow in the hole 9, the heat removal efficiency is also improved.
[0029]
The cooling air 10a flowing through the main channel 10 flows from the inlet 4a toward the outlet 4b while cooling the outer surface of the tab 7. Since the cooling air 10a sequentially removes heat from the upstream side, its temperature increases as it goes downstream, but the temperature does not increase because it is not in contact with a heating element such as a battery. As the diverted flow 11b of the cooling air 11a flowing through the sub flow channel 11 flows from the hole 9 of the double bottom partition plate 3, the temperature rise on the downstream side is suppressed. Thereby, the battery 8 arranged on the downstream side can also be cooled to the same extent as the upstream side. The cooling air 10a flowing through the main flow path 10 also cools the bus bar cables 13 and is discharged from the outlet 4b.
[0030]
The cooling air 12 a flowing through the second sub-flow channel 12 flows downstream while cooling the upper surface side of the control circuit board 2. The lower surface side of the control circuit board 2 is cooled by the diversion flow 10b of the main flow 10a and the diversion flow 11b of the cooling air 11a. These diversion flows 10b and 11b wrap around toward the upper surface side of the control circuit board 2 from the gap 2b formed between the control circuit board 2 and the case body 4 and merge with the cooling air 12a of the second sub-flow channel 12. To do. The cooling air 12a joined by the diversions 10b and 11b cools the bus bar cables 13 and is discharged from the outlet 4b.
[0031]
As described above, the cooling air 10a, 11a, 12a is formed by the wall formed by the two partition plates including the control circuit board 2 and the double bottom partition plate 3 and the tabs 7 of the plurality of batteries 8 arranged in a row. The cooling air that has cooled the battery 8 body, the tab 7 of the battery 8, the control circuit board 2 and the bus bar cables 13 is gathered into one at the outlet 4b and is discharged to the outside of the case body 4.
[0032]
As described above, the secondary battery unit 1 of the present embodiment uses the two partition plates including the control circuit board 2 and the double bottom partition plate 3 in which the holes 9 are formed, and the tab 7 of the battery 8. By dividing the cooling air into three, the following effects can be obtained.
[0033]
First, in the secondary battery unit 1 of this embodiment, the tab 7 that is the electrode terminal of the battery 8 has a function as a flow path wall, so that a dedicated rectifying plate or the like is not necessary, and the secondary battery unit The number of component parts of 1 can be reduced.
[0034]
Further, the secondary battery unit 1 of the present embodiment flows in the downstream direction by flowing along the tab 7 of the battery 8 by the diversion 11b supplied from the plurality of holes 9 formed in the double bottom partition plate 3. Therefore, the temperature rise of the cooling air 10a that causes the temperature to rise can be suppressed, so that the cooling of the battery 8 disposed on the downstream side does not become insufficient.
[0035]
In addition, since the secondary battery unit 1 of the present embodiment is sized so that the control circuit board 2 also functions as a flow path wall, a dedicated rectifying plate or the like is unnecessary, and the number of components of the secondary battery unit 1 is reduced. Can be reduced.
[0036]
Although the secondary battery unit 1 of the present embodiment has been described as being mounted on an electric vehicle, it goes without saying that the secondary battery unit 1 is installed in a vehicle other than an electric vehicle or a hybrid vehicle, a vehicle other than a vehicle, or any other place. Can be used.
[0037]
In the present embodiment, an example in which there are three flow paths through which cooling air flows with respect to the two partition plates including the control circuit board 2 and the double bottom partition plate 3 is shown. The number of flow paths is not limited to two, and the number of flow paths may be n + 1 with respect to the number n of partition plates.
(Second Embodiment)
FIG. 4 shows a top cross-sectional view of the secondary battery unit of the present embodiment.
[0038]
The secondary battery unit 51 of the present embodiment has a configuration in which a net-like member is used as the double bottom partition plate 53 instead of the double bottom partition plate 3 in which the plurality of holes 9 shown in the first embodiment are formed. It has become. In addition, since a structure and effect other than this are the same as that of the secondary battery unit 1 demonstrated in 1st Embodiment fundamentally, detailed description is abbreviate | omitted.
[0039]
In the present embodiment, similarly to the secondary battery unit 1 of the first embodiment, the cooling of the battery 58 disposed on the downstream side is not insufficient for the battery 58 disposed on the upstream side. In the case of the present embodiment, since the existing material such as a resin mesh, a wire mesh, or a punching metal can be used as the double bottom partition plate 53, the manufacture becomes easy. In the case of a wire mesh or punching metal, it is preferable to use a material that has been subjected to treatment such as application of an insulating agent, insulating resin coating, or baking of insulating rubber in order to provide insulation.
[0040]
【The invention's effect】
As described above, according to the present invention, a part of the wall surface of the main channel is formed by joining the conductive heat transfer members extending from the inside of the main body of each secondary battery to the outside. Therefore, it is possible to efficiently apply the cooling air to the heat transfer member, and the cooling air supplied from the holes of the double bottom partition plate through the gap formed between the heat transfer members is below the heat transfer member. Therefore, the secondary battery can be effectively cooled. Thereby, the function fall of the secondary battery by the temperature rise of a secondary battery and a function fluctuation | variation can be suppressed, and the function stabilization and long life of a secondary battery unit can be aimed at.
[0041]
Further, the secondary battery unit of the present invention is configured such that the main flow path and the sub flow path are communicated with each other by the communication portion formed in the partition plate, so that the cooling air flows from the sub flow channel side to the main flow channel side through the communication portion. Therefore, it is possible to suppress an increase in the temperature of the cooling air in the main flow path that increases in temperature as it flows from the inlet side to the outlet side. Thereby, it becomes possible to suppress the battery cooling imbalance between the upstream side and the downstream side.
[0042]
Furthermore, the present invention capable of obtaining the above effects can be manufactured easily because it requires a relatively simple structure to realize, for example, it does not require a separate part for applying cooling air to the heat transfer member.
[Brief description of the drawings]
FIG. 1 is a schematic sectional side view of a secondary battery unit according to a first embodiment of the present invention.
2 is a schematic top cross-sectional view of the secondary battery unit shown in FIG.
FIG. 3 is a schematic perspective view of a laminated battery mounted on the secondary battery unit of the present invention.
FIG. 4 is a schematic top sectional view of a secondary battery unit according to a second embodiment of the present invention.
[Explanation of symbols]
1, 51 Secondary battery unit 2 Control circuit board 2a Control circuit 2b Gap 3, 53 Double bottom partition plate 4 Case body 4a Inlet 4b Outlet 4c Bottom surface 4d Side surface 4e Top surface 5 Duct outlet 6 Exhaust blower 7 Tab 7a Tab gap 8, 58 Battery 9 Hole 10 Main flow paths 10a, 11a, 12a Cooling air 10b, 11b Split flow 11 First sub flow path 12 Second sub flow path 13 Busbar cables 14 Strut 15 Duct inlet 16 Laminate sheet

Claims (10)

In a secondary battery unit that houses a plurality of secondary batteries in a case in which an inlet for introducing cooling air and an outlet for discharging cooling air are formed,
Each of the secondary batteries is arranged, and a part of the wall surface is formed by joining the conductive heat transfer members extending from the inside of the main body of each of the arranged secondary batteries to the outside. A main flow path communicating with the introduction port and the discharge port;
At least one sub-channel formed between at least one partition plate in which a communication portion is formed and a wall surface of the case, and communicated with the introduction port and the discharge port, and the main channel; A secondary battery unit, wherein the sub-flow path is communicated with the communicating portion. The said partition plate is a double bottom partition plate which mounts each said secondary battery on the said partition plate, and forms a 1st subchannel between the bottom surfaces of the said case. Secondary battery unit. The secondary battery unit according to claim 2, wherein the communication part of the double bottom partition plate is a plurality of holes formed in the double bottom partition plate. The secondary battery unit according to claim 2, wherein the double bottom partition plate is made of a net-like member. The communicating portion generates a diversion having a flow velocity higher than the flow velocity of the cooling air flowing through the sub-flow path in a direction intersecting the cooling air flowing through the main flow path, and the diversion flows are joined to each other. 5. The heat transfer member according to claim 1, wherein the heat transfer member is cooled by being supplied to gaps formed between the heat transfer members and being applied to the heat transfer members. Secondary battery unit. The secondary battery according to any one of claims 1 to 5, wherein the partition plate is a control circuit board including a control circuit that forms a second sub-flow channel with the upper surface of the case. unit. The secondary battery unit according to claim 6, wherein the communication part of the control circuit board is a gap formed between a side surface of the case and the control circuit board. The main flow channel and each sub flow channel are merged and then communicated with the discharge port, and a bus bar, a cable, a fuse, a relay, or a combination of these components is arranged in the merged region, The secondary battery unit according to claim 1. The secondary battery unit according to claim 1, wherein the heat transfer member is an electrode terminal of the secondary battery. 10. The secondary battery unit according to claim 1, wherein the number of the partition plates is n, and n + 1 cooling air flow paths are provided. 11.

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