JP5162089B2 - Cooling structure - Google Patents

Description

  The present invention relates to a cooling structure that cools an electric device assembly configured by assembling a plurality of film-clad electrical devices (for example, film-clad batteries) with cooling air.

  In recent years, as a power source for driving an electric vehicle or the like, for example, an assembled battery including a plurality of film-clad batteries functioning as a lithium ion secondary battery is used. Further, in such an assembled battery, it is known that each film-covered battery needs to be cooled in order to maximize the charge / discharge performance of the battery (or not to shorten the battery life). ing.

  When forming an assembled battery, a method of stacking batteries and storing them in a battery case is generally employed. In such a case, cooling air flows through the gaps between the stacked batteries (for example, Patent Document 1).

By the way, in configuring the assembled battery, the battery cells may be arranged side by side in a plane (such an arrangement is hereinafter referred to as “flat placement”). FIG. 4 schematically shows a state in which the battery cells 120A and 120B that are laid flat are stacked. In such a case, the cooling air is supplied from the battery cell 120A side (or from the 120B side), passes through the gap 121A between the stacked battery cells 120A, and then passes through the gap 121b between the stacked battery cells 120b. It is discharged after.
JP 2004-39484 A

  However, when cooling an assembled battery as shown in FIG. 4, even if it is sent from one battery cell side (120A side) to the other battery cell side (120B side), one battery cell and the other battery It is difficult to cool the cell uniformly. That is, the cooling air is warmed when it passes through one battery cell 120A, and this warm cooling air is supplied to the other battery cell 120B, so that there is a cooling effect between the two battery cells. Because it is different.

  As described above, the film-clad battery has been described as an example. However, the above-described problem is not limited to the battery, and may occur in a device in which a capacitor or the like is disposed as an electric device element in a film package, for example. .

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a cooling structure for an electric device assembly capable of uniformly cooling each film-covered electric device constituting the electric device assembly. Is to provide.

In order to achieve the above object, according to the cooling structure for an electric device assembly of the present invention, the electric device element for storing and outputting electric energy is accommodated in the film package, and the electrode tab is drawn out from the sealing portion of the film package. the film was covered electrical device, in the cooling structure in which a plurality of the film-covered electrical device to cool the electrical devices assemblies are laminated at a predetermined pitch with a gap, for cooling the film-covered electrical device Cooling air is supplied to a gap between one electrical device assembly in a first direction, which is a direction toward another adjacent electrical device assembly. It is supplied with the direction toward the second direction in the opposite direction, which is formed between said one electrical device assembly and the other electrical devices aggregate Is discharged to the outside flow between one of said the electrical device assembly and other of the electrical device assembly, and cooling air from the first direction, the cooling air and said from said second direction as not hit directly in space, characterized that you have been arranged shifted in the lamination direction.

  The cooling structure of the present invention supplies cooling air to each of the electrical device assemblies arranged adjacent to each other. For this reason, it is possible to cool each film-covered electrical device evenly as compared with the system in which the cooling air that has cooled one electrical device assembly is continuously supplied to the other electrical device assembly and cooled.

In order to achieve the above object, according to another cooling structure of the present invention, an electrical device element for storing and outputting electrical energy is accommodated in a film package, and an electrode tab is pulled out from a sealing portion of the film package. A cooling structure for cooling an electrical device assembly, wherein the electrical device assembly is a film-clad electrical device, wherein a plurality of the film-clad electrical devices are stacked at a predetermined pitch with a gap between the electrical device assembly and the gap of the electrical device assembly. The gap between the other electric device assemblies adjacent to the one electric device assembly is shifted in the stacking direction, and the cooling air from the gap of the one electric device assembly and the other electric device are arranged. The cooling air from the gap of the device assembly is combined in the space formed between the one electrical device assembly and the other electrical device assembly. And, characterized in that it is discharged to the outside flows through the space.

In the cooling structure of the present invention, one electrical device assembly and another electrical device assembly may be shifted in the stacking direction by a half pitch with respect to the pitch. In particular, each film-covered electrical device is stored in a storage case, and the cooling air supplied with the gap of one electrical device assembly directed in the first direction and the gap between the other electrical device assemblies are second. The cooling air supplied toward the direction may flow into the space toward the side wall of the storage case that is disposed to face the exit of the gap. Cooling air that flows into the space from the gap flows in a direction that strikes the side wall of the storage case at a position facing the exit of the gap, so that the cooling air that flows in the first direction and the cooling air that flows in the second direction are mutually It can be merged without disturbing the flow. Thereby, cooling air can be discharged | emitted favorably outside.

  In the cooling structure of the present invention, the space formed between the electric device assemblies is also used as an exhaust gas passage for guiding the gas discharged from the film-covered electric device to the outside. Also good. In this case, since it is not necessary to provide a separate exhaust gas passage or a separate cooling channel, a simple configuration can be achieved.

  As described above, according to the present invention, the cooling air is supplied to each of the adjacent electric device assemblies. For this reason, it is possible to cool each film-covered electrical device evenly as compared with the system in which the cooling air that has cooled one electrical device assembly is continuously supplied to the other electrical device assembly and cooled.

  FIG. 1 shows a partially broken perspective view of a film-clad battery applicable to this embodiment. FIG. 2 shows a plan view of a cell case that houses the battery cell 20. FIG. 3 is a schematic diagram showing the arrangement of battery cells housed in the cell case and the flow of cooling air in the assembled battery of this embodiment.

  As the battery cell 20, it is possible to use a conventional general film-clad battery as shown in FIG. The battery cell 20 is a lithium ion secondary battery in which a battery element 52 is accommodated together with an electrolytic solution in a sealed space formed by two exterior films 24 constituting a film package. Four sides of the outer peripheral portion of the exterior film 24 are sealing portions 23 in which the films are heat-sealed, and among these, sheet-like electrode tabs 25a and 25b are drawn out from two sides on the short side.

  Each exterior film 24 is formed with a cup portion (not shown with a symbol) having a shape corresponding to the battery element 52. The cup portion includes a flat central portion 26a formed in a region covering the upper surface (or lower surface) of the battery element 52 and an inclined surface 26b formed around the center portion 26a. When the battery cell 20 is cooled, it is most effective to cool the central portion 26a.

  The cell case 50 is a rectangular frame composed of two opposing side walls 50a and two short side walls 50b that are substantially orthogonal to the side walls 50a and are opposed to each other. Each short side wall 50b of the cell case 50 is formed with a notch 50e for extending the electrode of the battery cell 20 accommodated in the cell case 50 to the outside. The battery cell 20 is housed in the cell case 50 with the electrode extended in this manner.

  The side wall 50a is connected by an exhaust gas passage 51c for guiding the gas discharged from the gas discharge portion 8 of the battery cell 20 to the outside. In this embodiment, since the gas discharge part 8 of the battery cell 20 is formed in the approximate center of the sealing part 23, the exhaust gas passage 51c is also formed in the approximate center of the side wall 50a accordingly. The gas discharged from the gas discharge portion 8 is discharged to the outside through the exhaust gas passage 51c.

  The battery cells 20 housed in the cell case 50 are stacked and modularized. In FIG. 3, a module 30A in which four battery cells 20A form a gap 21A and are stacked at a pitch p, and a module 30B in which four battery cells 20B form a gap 21B and are stacked at a pitch p. It is shown. The module 30A is shifted from the module 30B by a half pitch (0.5p) in the stacking direction and is arranged adjacent to each other with a predetermined space therebetween. As will be described later, the space is a combined flow path 22 in which cooling air flows and flows, and is also used as a flow path for gas through which the gas discharged from the gas discharge unit 8 flows.

  As shown in FIG. 3, the cooling air flows into the gaps 21A and 21B from the outside of the modules 30A and 30B, and flows out to the combined flow path 22 formed between the modules 30A and 30B.

  Hereinafter, the flow of the cooling air will be described in detail.

  Cooling air is supplied to the gap 21A of the module 30A from the direction of the arrow α to remove heat from the central portion 26a of the battery cell 20 (the cooling air flows from one side wall 50a to the other side wall 50a with respect to the cell case 50. In the direction indicated by the arrow α (see FIG. 2), and flows out to the combined flow path 22. The cooling air flowing out from the gap 21A flows out toward the side wall 50a of the cell case 50 in the position facing the gap 21A in the cell case 50 of the module 30B. Similarly, the cooling air is supplied from the direction of the arrow β to the gap 21B of the module 30B and flows out to the joint channel 22. The cooling air flowing out from the gap 21B flows toward the side wall 50a of the cell case 50 of the module 30A. By being shifted by a half pitch (0.5p) in the stacking direction, the cooling air that flows in the α direction and the cooling air that flows in the β direction alternately flow out of the gaps 21A and 21B. For this reason, each cooling air joins in the joining channel 22 without colliding directly, and is discharged | emitted outside.

  In the case of this embodiment, the cooling air is supplied to each of the module 30A and the module 30B. The method of cooling the battery cell 20B after the cooling air supplied from one direction of the arrow α has cooled the battery cell 20A has a problem that the battery cell 20B to be cooled later is not sufficiently cooled. In the embodiment, since the battery cells 20A and 20B are separately cooled, both the battery cells 20A and 20B can be cooled equally and satisfactorily.

  In the case of the present embodiment, the module 30A is arranged so as to be shifted by a half pitch with respect to the module 30B, so that the cooling air flowing out from the gap 21A flows out toward the opposing side wall 50a. In this way, the cooling air that has flowed into the combined flow path 22 is changed in the flow direction by the side wall 50a, and is combined with another flow and discharged from the discharge port 60. Since the modules 30A and 30B are shifted by a half pitch, the cooling air that flows out of the gap 21A and the cooling air that flows out of the gap 21B do not directly collide, that is, inhibit the flow of each other. Instead, they merge in the combined flow path 22 and flow toward the discharge port 60. For this reason, it is possible to prevent the cooling air from staying in the combined flow path 22.

  As described above, according to the present embodiment, the modules are shifted by a half pitch, the cooling air is supplied from both sides to the module in such a state, and the cooling air that has taken away the heat of the battery cells is discharged from between the modules. Therefore, it is possible to realize uniform cooling of the battery as compared with the method of sequentially cooling from one direction. In the present embodiment, a member for forming the cooling path is not particularly used, but the flow path is formed using the wall surface of the cell case, which is advantageous in terms of cost.

  In the case of the present embodiment, the combined flow path 22 is also used as a gas path that is discharged from the gas discharge section 8 and passes through the exhaust gas passage 51c, so that it is not necessary to separately form a flow path for exhaust gas. Therefore, the configuration can be simplified.

  In the present embodiment, the cooling air discharged from the gap 21 has been shown as hitting the side wall of the cell case at the opposite position. However, the present invention is not limited to this. That is, in the case of stacking without using the cell case, or when stacking using the cell case that does not have a portion corresponding to the side wall, the cooling air does not hit the side wall but directly hits the side wall surface of the battery cell. The structure which changes to the discharge port side may be sufficient. In this case, it is advantageous in that heat can also be taken from the side wall surface of the battery. Further, since the weight is reduced by omitting the cell case or omitting the side wall, it is advantageous in terms of weight.

  Although not described in detail in the above description, the battery element 52 constituting the lithium ion secondary battery is specifically made of a positive electrode active material such as lithium / manganese composite oxide or lithium cobaltate made of aluminum foil or the like. Alternatively, a positive electrode plate coated on both surfaces and a negative electrode plate coated with a lithium-doped / dedoped carbon material on both surfaces such as a copper foil may be alternately stacked via separators. In addition to the lithium ion secondary battery, the battery element 52 may constitute another type of chemical battery such as a nickel metal hydride battery, a nickel cadmium battery, a lithium metal primary battery or secondary battery, or a lithium polymer battery. Good. Further, the battery element 52 is not limited to the stacked type as in the present embodiment, and a belt-like positive electrode side active electrode and a negative electrode side active electrode are stacked with a separator interposed between them, and then compressed into a flat shape. The winding type of the structure where the positive electrode side active electrode and the negative electrode side active electrode were laminated | stacked alternately by this may be sufficient. The electric device element constituting the film-clad electric device may be a capacitor such as an electric double layer capacitor or a capacitor element exemplified by an electrolytic capacitor.

  Moreover, the exterior film 24 is a laminate film, for example, and any laminate film may be used as long as the battery element can be hermetically sealed. To give a specific example, a resin layer that is heat-meltable and serves as an inner surface, a non-venting layer made of a metal thin film, and a protective layer (such as nylon) that are laminated on the outer surface are laminated in this order. A laminated film may be used. Further, the film package is not limited to the one constituted by the two exterior films 24, and may be a package in which, for example, one exterior film is folded and its three sides are heat-sealed. The drawing position of each electrode tab 25 is not particularly limited, and two electrode tabs for the positive electrode and the negative electrode may be drawn from one side of the sealing portion of the film package.

It is a partially broken perspective view of a film-clad battery applicable to the present invention. It is a top view of the storage case which stores a battery cell. It is a schematic diagram which shows the arrangement | sequence of the battery cell accommodated in the storage case, and the flow of cooling air in the assembled battery of this invention. It is a schematic diagram for demonstrating the cooling condition of the conventional flat battery.

Explanation of symbols

8 Gas discharge part 20, 20A, 20B Battery cell 21A, 21B Gap 22 Joint flow path 23 Sealing part 24 Exterior film 25a, 25b Electrode tab 26a Central part 26b Inclined surface 30A, 30B Module 50 Cell case 50a Side wall 50e Notch 50b Short side wall 51c Exhaust gas passage 52 Battery element 60 Outlet

Claims (5)

A film-clad electrical device in which an electrical device element for storing and outputting electrical energy is housed in a film package and an electrode tab is drawn out from a sealing portion of the film package , wherein the plurality of the film-clad electrical devices In the cooling structure that cools the electrical device assembly formed by laminating at a predetermined pitch with a gap,
Cooling air for cooling the film-clad electrical device is supplied to a gap between one electrical device assembly toward a first direction that is a direction toward another adjacent electrical device assembly, The gap between the other electrical device assemblies is supplied in a second direction opposite to the first direction, and is formed between the one electrical device assembly and the other electrical device assembly. The one electric device assembly and the other electric device assembly are cooled by the cooling air from the first direction and the cooling from the second direction. so that the wind does not collide directly with the space, the cooling structure for an electric device assembly, wherein that you have been arranged shifted in the lamination direction. A film-clad electrical device in which an electrical device element for storing and outputting electrical energy is housed in a film package and an electrode tab is drawn out from a sealing portion of the film package, wherein the plurality of the film-clad electrical devices In the cooling structure that cools the electrical device assembly formed by laminating at a predetermined pitch with a gap,
The gap of one electrical device assembly and the gap of another electrical device assembly adjacent to the one electrical device assembly are shifted in the stacking direction, and the electrical device assembly The cooling air from the gap and the cooling air from the gap of the other electric device assembly merge in a space formed between the one electric device assembly and the other electric device assembly. A cooling structure for an electrical device assembly, wherein the electrical device assembly is discharged outside through the space. 3. The cooling structure according to claim 1, wherein one electric device assembly and the other electric device assembly are arranged in the stacking direction so as to be shifted by a half pitch with respect to the pitch.   Each film-clad electrical device is stored in a storage case, the cooling air supplied toward the first direction through the gap of one electrical device assembly, and the other electrical device assembly The cooling air supplied with the gap toward the second direction flows into the space toward the side wall of the storage case that faces the outlet of the gap, respectively. The cooling structure described.   The said space formed between each said electric device aggregate | assembly is combined with the waste gas passage for inducing | guiding | deriving the gas discharged | emitted from the film-clad electrical device outside, The any one of Claim 1 thru | or 4 The cooling structure as described in.

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