JP2021022515A - Heat exchanger using laminate material, in-vehicle battery module and heat exchanger manufacturing method using laminate material - Google Patents

Abstract

To provide a heat exchanger using a laminate material to which an entrance/exit member can be attached in a stable state for a long period of time and which can obtain sufficient durability and enhance product worth, and a method for manufacturing the same.SOLUTION: The present invention targets a heat exchanger using a laminate material which includes a casing 2 configured by a laminate material L having a resin coating layer 52 on at least an outer surface side of a metal layer 51, and in which a heat medium is caused to flow into and out of the inside of the casing 2 through an entrance/exit 22 penetrating the laminate material L. The heat exchanger includes a piping member 3 having a hole 32 corresponding to the entrance/exit 22 outside the entrance/exit 22 of the casing 2. The piping member 3 is made of a resin through which laser light P is transmitted, the piping member 3 and the laminating material L are in contact with each other, and the heat exchanger has a joint portion W at which a coating layer 52 constituting the outer layer of the laminate material L and the piping member 3 are welded and jointed to each other.SELECTED DRAWING: Figure 5

Description

The present invention relates to a mounting structure of a heat exchanger and a piping member having a casing composed of a laminated material in which a resin coating layer is laminated on a metal layer.

Hybrid electric vehicles (HEVs), electric vehicles (EVs), and the like are equipped with a battery device that supplies electric power for driving an electric motor. As such a battery device, a device in which a large number of small cell cells made of various secondary batteries such as a lithium secondary battery are connected in series or in parallel to form an assembled battery is generally used. Particularly in recent years, in order to extend the cruising range of an electric vehicle, a plurality of assembled batteries are combined in series or in parallel, and the capacity of the battery device is further increased.

On the other hand, since the performance and life of a lithium secondary battery, which is often used as a battery device, changes greatly depending on the operating temperature, it is preferable to control the temperature to an appropriate temperature for efficient use over a long period of time. However, when used in the form of a plurality of assembled batteries as described above, since the plurality of assembled batteries are closely arranged, the heat generated from each assembled battery and each cell can be effectively released. Is difficult, and the temperature of each set of batteries may rise, resulting in a decrease in performance and life.

Therefore, a technique has been developed in which a plurality of assembled batteries are cooled by using a thin heat exchanger as shown in Patent Document 1 below. In this heat exchanger, two metal dish-shaped plates are opposed to each other to form a heat exchanger (flat tube), and a flat tube is arranged between each of a plurality of assembled batteries to form an assembled battery. The heat generated from each of the above cells is released to the outside through the refrigerant (cooling water) flowing in the flat tube.

Against this background of technology, heat exchangers for cooling a plurality of assembled batteries as an automobile battery device are required to be as thin, small and lightweight, and low in cost as much as other automobile parts. As part of this, the adoption of heat exchangers using highly flexible laminate materials is being considered.

A heat exchanger using a laminated material is provided with a casing composed of two laminated materials in which a resin coating layer is laminated on both sides of an aluminum layer, and is configured so that a refrigerant can be circulated inside the casing. Has been done. A casing is arranged between each of the plurality of assembled batteries so that the heat generated from each cell of the assembled batteries is discharged to the outside through the refrigerant flowing inside each casing.

Japanese Unexamined Patent Publication No. 2012-199149

However, in the connection between the heat exchanger and the piping member using the above-mentioned laminate material, the conventional metal joining method such as welding or brazing cannot be applied, and it is suitable for mass production, stable and reliable. There was a problem that a high bonding method could not be established.

The present invention has been made in view of the above problems, and the piping member can be attached in a stable state for a long period of time, sufficient durability can be obtained, and the product value can be improved. It is an object of the present invention to provide a heat exchanger using a laminated material and a method for manufacturing the heat exchanger.

In order to achieve the above object, the gist of the present invention is as follows.
[1] A casing made of a laminate material provided with a resin coating layer on at least the outer surface side of the metal layer is provided, and a heat medium flows out to the inside of the casing through an inlet / outlet penetrating the laminate material. In a heat exchanger using a laminated material that is allowed to enter
A piping member having a hole corresponding to the entrance / exit is provided outside the entrance / exit of the casing. The piping member is made of a resin that transmits laser light, and the piping member and the laminating material come into contact with each other to form an outer layer of the laminating material. A heat exchanger using a laminated material, wherein the constituent layer and the piping member have a joint portion joined to each other by welding.
[2] A heat exchanger using the laminate material according to the above item 1, wherein the joint portion covers the entire circumference of the doorway.
[3] The heat exchanger using the laminate material according to the above item 1 or 2, wherein the piping member is made of a resin having a laser light transmittance of 10% or more.
[4] The heat exchanger using the laminate material according to any one of items 1 to 3 above, wherein the coating layer constituting the outer layer of the laminate material and the piping member are made of the same material.
[5] The laminate material according to any one of the above items 1 to 4 is used, in which a flange member for improving the strength of the joint portion is provided along the inner peripheral surface of the laminate material in the vicinity of the entrance / exit. Heat exchanger.
[6] The heat exchanger using the laminate material according to item 5 above, which has a fitting structure for determining a combination position of the piping member and the flange member.
[7] An in-vehicle battery module in which a heat exchanger using the laminate material according to any one of items 1 to 6 above and a battery unit are combined.
[8] A casing made of a laminating material provided with a resin coating layer on at least the outer surface side of the metal layer is provided, and a heat medium flows out to the inside of the casing through an inlet / outlet penetrating the laminating material. In the method of manufacturing a heat exchanger using a laminated material to be inserted,
A piping member having a hole corresponding to the entrance / exit is provided outside the entrance / exit of the casing. The piping member is made of a resin that transmits laser light, and the piping member and the laminating material are brought into contact with each other to bring the piping member into contact with each other. A laminating material characterized in that the coating layer constituting the outer layer of the laminating material and the piping member are bonded to each other by laser welding due to the transmitted laser light generating heat in the metal layer was used. How to make a heat exchanger.
[9] The method for manufacturing a heat exchanger using the laminate material according to item 8 above, wherein the laser light passes through the outer wall and the lower wall of the piping member.

According to the heat exchanger using the laminate material of the invention [1], the piping member is made of a resin that transmits laser light, and the resin coating layer constituting the outer layer of the laminate material and the piping member are in contact with each other. Since they are joined to each other by welding, the piping members can be attached in a stable state for a long period of time. Therefore, sufficient durability can be obtained and the product value can be improved.

According to the heat exchanger using the laminate material of the invention [2], since the joint portion extends over the entire circumference of the entrance / exit, the piping member can be more reliably attached in a stable state for a long period of time.

According to the heat exchanger using the laminate material of the invention [3], the piping member is made of a resin having a laser light transmittance of 10% or more, so that the energy of the laser light is efficiently used for joining. can do.

According to the heat exchanger using the laminate material of the invention [4], since the material of the coating layer constituting the outer layer of the laminate material and the piping member are the same, both can be reliably joined.

According to the heat exchanger using the laminate material of the invention [5], since the flange member is provided along the inner peripheral surface of the laminate material in the vicinity of the entrance / exit, the strength when the piping member is attached is improved. be able to.

According to the heat exchanger using the laminated material of the invention [6], since the combination position of the piping member and the flange member is determined, the piping member can be reliably positioned.

According to the in-vehicle battery module of the present invention [7], since the heat exchanger made of the laminated material is used, it is possible to provide a lightweight and inexpensive in-vehicle battery module.

According to the method for manufacturing a heat exchanger using the laminate material of the invention [8], the same effect as the invention of the heat exchanger using the laminate material of the above [1] can be obtained.

According to the method for manufacturing a heat exchanger using the laminate material of the present invention [9], the laser light is transmitted through the outer wall and the lower wall of the piping member, and the laser light is absorbed by the metal layer. It can be selectively heated and welded by utilizing absorption. Furthermore, even the inside of a complicated sealed structure can be joined.

FIG. 1 is a perspective view schematically showing a heat exchanger using a laminate material according to an embodiment of the present invention. FIG. 2 is a perspective view schematically showing an exploded heat exchanger using a laminate material according to an embodiment of the present invention. 3A and 3B are enlarged views showing a flange member of a heat exchanger using a laminate material according to an embodiment of the present invention, FIG. 3A is a perspective view, and FIG. 3B is FIG. 3B. It is sectional drawing which shows roughly the cross section in -B line. 4A and 4B are views showing a cross section taken along the line AA of FIG. 1, FIG. 4A is a cross-sectional view showing the entire heat exchanger, and FIG. 4B is a cross-sectional view showing a part of the heat exchanger. .. FIG. 5 is an enlarged cross-sectional view showing a part of the cross section taken along the line AA of FIG. FIG. 6 is a cross-sectional view showing a process of forming a casing of a heat exchanger using a laminate material according to another embodiment of the present invention, and FIG. 6A is a cross-sectional view showing before formation, and FIG. Is a cross-sectional view showing the process of formation, and FIG. (C) is a cross-sectional view showing the state after formation.

FIG. 1 is a perspective view schematically showing the heat exchanger 1 of the present embodiment, FIG. 2 is a perspective view schematically showing the heat exchanger 1 of the present embodiment disassembled, and FIG. 3 is a heat exchange of the present embodiment. A view showing the flange member 7 of the vessel 1, FIGS. 4 and 5 is a cross-sectional view taken along the line AA of FIG. 1, and FIG. 6 is a diagram illustrating a casing 2 of the heat exchanger 1 in another embodiment.

The heat exchanger of the present invention cools a battery device that supplies electric power for driving an electric motor such as an electric vehicle.

As shown in FIGS. 1 and 2, the heat exchanger 1 using the laminate material of the present embodiment includes three casings 2 and two piping members 3 which are brought into contact with both ends of each casing 2 from above. It has a configuration in which the casing 2 and each piping member 3 are arranged so that their longitudinal directions are orthogonal to each other.

In this embodiment, three casings 2 are used, but the number of casings 2 is not limited to this, and the number of casings 2 can be changed according to the application of the heat exchanger 1.

The casing 2 is used for heat exchange between the heat medium flowing inside the casing 2 and the member to be cooled by arranging the member to be cooled in contact with the surface thereof, and is composed of the laminate material L described later. Will be done.

As the heat medium of the present embodiment, a refrigerant such as water or antifreeze is used.

Although not shown here, for example, a battery unit is used as the member to be cooled. This battery unit is a combination of an assembled battery in which a large number of secondary batteries such as a lithium ion battery are connected or a plurality of assembled batteries in series or in parallel. A combination of the heat exchanger 1 of the present embodiment and this battery unit constitutes an in-vehicle battery module.

As shown in FIGS. 2, 4 (a) and 4 (b), the casing 2 of the present embodiment is composed of two laminating materials L. That is, one laminating material L is formed with an oval recess 23 and an outer peripheral edge portion 21, and the other laminating material L is overlapped so as to close the recess 23. Then, the outer peripheral edge portion 21 and the other laminating material L are integrally joined by thermocompression bonding (thermocompression bonding), so that the casing 2 is formed in an oval shape.

In the present embodiment, the shape of the casing 2 is an oval shape, but the shape may be rectangular, elliptical, or square. Further, the casing 2 is not limited to these shapes, and the casing 2 may have a shape such that a heat medium flows inside the casing 2.

Further, the recess 23 is formed by press working such as deep drawing. Deep drawing is a processing method in which a pair of male and female dies, a punch and a die, is used to apply pressure to a single metal plate to draw (compress) it into a concave shape.

Further, in the present embodiment, the casing 2 is formed by superimposing the two laminating materials L, but the casing 2 may be formed by using only one laminating material L. That is, as shown in FIG. 6 (a), the other end side of the laminating material L having the recess 23 formed on one end side is bent in the D direction shown in FIG. 6 (b), and is shown in FIG. 6 (c). As described above, even if the casing 2 is formed by superimposing the laminating material L so that both ends coincide with each other and integrally joining the outer peripheral edge portion 21 on one end side and the other end by thermocompression bonding (thermocompression bonding). Good.

The laminate material L is formed by arranging a resin coating layer on at least the outer surface side of the metal layer and integrating them in a laminated manner.

As shown in FIG. 5, the laminating material L of the present embodiment is composed of a three-layer laminating material in which coating layers 52 and 53 are arranged on both sides of the metal layer 51 and integrated in a laminated manner. Further, as shown in FIGS. 4 (a), 4 (b) and 5, the doorway 22 is formed so as to penetrate the laminate material L, and a flange member 7 is provided in the vicinity of the doorway 22. ..

The metal constituting the metal layer 51 of the present embodiment is aluminum. The term aluminum is used to include not only pure aluminum but also aluminum alloys.

Further, the thickness of the aluminum layer constituting the metal layer 51 of the present embodiment is preferably set to 8 μm to 500 μm, more preferably 20 μm to 200 μm.

The coating layers 52 and 53 are made of a resin, and a thermoplastic resin or a thermosetting resin can be used. For example, polyamide resin, ionomer resin, high density polyethylene resin (hereinafter HDPE), low density polyethylene resin (LDPE), acrylic butadiene copolymer resin (ABS), polyvinyl chloride resin (PVC), polystyrene resin (PS), Polymethyl methacrylate resin (PMMA), polyphenylene sulfide resin (PPS), polyimide resin (PI) or polycarbonate resin (PC) can be used.

HDPE is used as the coating layers 52 and 53 of the present embodiment. The coating layers 52 and 53 may be made of the same type of resin or different types of resin.

The entrance / exit 22 is for allowing a heat medium to flow in and out of the inside of the casing 2.

As shown in FIGS. 2, 4 (a) and 4 (b), the entrances and exits 22 of the present embodiment are provided so as to be located at both ends of the upper surface of the casing 2.

The flange member 7 is for improving the attachment strength when the piping member 3 described later is attached to the laminate material L.

3A and 3B are enlarged views of the flange member 7 of the present embodiment, FIG. 3A is a perspective view, and FIG. 3B is a schematic cross-sectional view taken along the line BB of FIG. 3A. It is sectional drawing shown in. As shown in these figures, the flange member 7 of the present embodiment includes a cylindrical upper flange member 72 and a substantially semicircular lower flange member 73, and both flange members 72 and 73 have the same inner diameter 75. It has and is integrally molded so that these central axes C coincide with each other. Further, the lower flange member 73 is provided with three protrusions 74 so as to project in the vertical direction.

Further, as shown in FIG. 5, the flange member 7 is arranged along the inner peripheral surfaces 61 and 62 of the laminating material L in the vicinity of the entrance / exit 22, and the upper flange member 72 has a protruding portion 71 protruding to the outside of the casing 2. doing. The lower flange member 73 and the protrusion 74 are in contact with the inner surface of the bottom wall of the casing 2.

The piping member 3 is for supplying and discharging a heat medium to the inside of the casing 2, and is made of a resin that transmits laser light. As the piping member 3, the resins exemplified in the coating layers 52 and 53 described above can be used, the melting point thereof is 100 ° C. to 200 ° C., and the transmittance of laser light is 10% or more.

Further, the piping member 3 may use a resin different from the resin used for the coating layer 52 constituting the outer layer of the laminate material L, but it is preferable to use the same resin as the resin used for the coating layer 52. This is because it is easier to weld the piping member 3 and the coating layer 52 when the same resin is used.

Further, as the piping member 3, a header or a manifold connecting a plurality of casings 2 can be used. Further, the present invention is not limited to these, and any device that can supply and discharge the heat medium to the inside of the casing 2 may be connected to other external devices.

In the piping member 3 of the present embodiment, a header made of HDPE is used, the melting point of which is about 120 ° C., and the transmittance of laser light is 14%.

As shown in FIGS. 1 and 2, the piping member 3 of the present embodiment has a rectangular parallelepiped shape, has an inflow port 33 or an outflow port 34 at the end in the longitudinal direction, and has a hole corresponding to the inlet / outlet 22 of the casing 2. It has 32. Then, the protruding portion 71 of the flange member 7 provided in each casing 2 has a structure of being fitted into each hole 32, and these protruding portions 71 are fitted into each hole 32 to be laminated with the piping member 3. The material L is in contact with the material L.

The inflow port 33 and the outflow port 34 are for supplying and discharging the heat medium to the piping member 3, respectively.

In the present embodiment, the heat medium is supplied to the piping member 3 from the inflow port 33 and discharged from the outflow port 34, but it may be supplied from the outflow port 34 and discharged from the inflow port 33.

The hole 32 is for injecting the heat medium supplied to one of the piping members 3 into the casing 2 and discharging the heat medium inside the casing 2 to the other piping member 3.

In the present embodiment, the same number of three holes 32 are formed in each piping member 3 corresponding to each casing 2.

The joint portion W is a portion in which the piping member 3 and the laminating material L are brought into contact with each other, and the coating layer 52 forming the outer layer of the laminating material L and the piping member 3 are joined to each other by welding.

The joint portion W of the present embodiment extends over the entire circumference of the doorway 22.

Next, a method of manufacturing the heat exchanger 1 of the present embodiment will be described.

First, a rectangular laminating material L is formed by adhering and integrating coating layers 52 and 53 made of HDPE on both sides of a metal layer 51 made of aluminum in a laminated manner. Two laminated materials L are prepared, and one of the laminated materials L is subjected to the above-mentioned deep drawing to form an oval recess 23, and both ends of the bottom surface of the recess 23 are penetrated to form two entrances and exits. 22 is formed.

Then, the flange member 7 is provided along the inner peripheral surfaces 61 and 62 of the laminating material L in the vicinity of each entrance / exit 22. At this time, the vicinity of the tip of the upper flange member 72, that is, the protruding portion 71 protrudes to the outside of the casing 2. Next, the other laminating material L is arranged so as to close the recess 23, and the outer peripheral edge portion 21 of the one laminating material L and the other laminating material L are integrally joined by thermocompression bonding (thermocompression bonding). , The oval-shaped casing 2 is formed. In the same way, three identical casings 2 are prepared.

Next, as the piping member 3, two HDPE rectangular parallelepiped headers having an inflow port 33 or an outflow port 34 at the end in the longitudinal direction and having a hole 32 corresponding to the inlet / outlet 22 of the casing 2 are prepared.

After preparing these, the casings 2 are arranged so as to be parallel in the longitudinal direction, and the inlet / outlet 22 of each casing 2 and the hole 32 of each piping member 3 are arranged so as to face each other. Then, the protruding portion 71 of the flange member 7 arranged in the laminate material L is fitted into the hole 32, the piping member 3 and the casing 2 are brought into contact with each other, and the piping member 3 and the casing 2 are brought into close contact with each other under pressure so as not to have a gap. .. At this time, the structure is such that the joint surface W does not bend.

Next, the contact surface between the piping member 3 and the casing 2 is irradiated with laser light P, and the piping member 3 and the casing 2 are joined by laser welding. At this time, since the contact surface is hidden by the piping member 3, the laser beam P is irradiated through the piping member 3.

That is, as shown in FIG. 5, the laser beam P is irradiated in the vertical direction from above the outer wall 35 of the piping member 3 toward the lower wall 36. Since the piping member 3 is a resin that transmits the laser light P, the laser light P transmits the outer wall 35 and the lower wall 36. At this time, the laser beam P is not so absorbed by the piping member 3, and the heat generated by the piping member 3 is suppressed so as to be equal to or lower than the melting point. Since the coating layer 52 in contact with the lower wall 36 is also a resin that transmits the laser light P, the laser light P transmits the coating layer 52 and reaches the metal layer 51.

Since the metal layer 51 is made of opaque aluminum, the laser beam P cannot pass through the metal layer 51 and is absorbed by the metal layer 51, so that the peripheral portion of the metal layer 51 generates heat. This heat-generating portion is the heat-generating region S. Then, the resin near the interface forming the lower wall 36 and the coating layer 52 in the heat generating region S softens and flows by heating, and is welded and joined at the joint portion W.

As described above, the heat exchanger 1 of the present embodiment is manufactured by joining the coating layer 52 constituting the outer layer of the laminate L and the piping member 3 to each other by laser welding.

Then, when the heat medium flows in from the inflow port 33 of the piping member 3, the heat medium circulates inside the casing 2, and the heat medium flows out from the outflow port 34 of the piping member 3. In this way, heat is exchanged between the heat medium circulated inside the casing 2 and the cooled member such as the above-mentioned battery unit arranged in contact with the surface of the casing 2, and the heat generated from the cooled member heats the heat medium. Is released through. As a result, the heating element such as the battery device of the vehicle is cooled.

According to the heat exchanger 1 using the laminate material of the present embodiment having the above configuration, the piping member 3 is made of a resin that transmits the laser beam P, and is a resin coating layer that constitutes the outer layer of the laminate material L. Since the 52 and the piping member 3 are in contact with each other and joined to each other by welding, the piping member 3 can be attached in a stable state for a long period of time. Therefore, sufficient durability can be obtained and the product value can be improved.

Further, since the piping member 3 is made of a resin having a transmittance of the laser light P of 10% or more, the energy of the laser light P can be efficiently used for joining. Further, since the material of the coating layer 52 forming the outer layer of the laminating material L and the piping member 3 are the same, both can be reliably joined.

Further, according to the method of manufacturing the heat exchanger 1 of the present embodiment, the laser beam P is transmitted through the outer wall 35 and the lower wall 36 of the piping member 3, and the metal layer 51 absorbs the laser beam P. Therefore, the piping member 3 The heat generation can be suppressed in the portion other than the heat generation region S, and in the heat generation region S, only the resin near the interface to be welded can be softened and flowed to generate heat to a temperature at which bonding can be performed. In this way, the metal layer 51 can be selectively heated and welded by utilizing the absorption of the laser beam P. Furthermore, even the inside of a complicated sealed structure can be joined.

The heat exchanger using the laminate material of the present invention can be suitably used as a heat exchanger for cooling the battery unit.

1: Heat exchanger 2: Casing 22: Doorway 3: Piping member 32: Hole 35: Outer wall 36: Lower wall 51: Metal layer 52, 53: Coating layer 61, 62: Inner peripheral surface 7: Flange member L: Laminate material P: Laser light W: Joint

Claims (9)

A casing made of a laminate material provided with a resin coating layer on at least the outer surface side of the metal layer is provided, and a heat medium is allowed to flow in and out of the inside of the casing through an inlet / outlet penetrating the laminate material. In the heat exchanger using the laminated material
A piping member having a hole corresponding to the entrance / exit is provided outside the entrance / exit of the casing. The piping member is made of a resin that transmits laser light, and the piping member and the laminating material come into contact with each other to form an outer layer of the laminating material. A heat exchanger using a laminated material, characterized in that the coating layer and the piping member are joined to each other by welding. The heat exchanger using the laminate material according to claim 1, wherein the joint portion covers the entire circumference of the doorway. The heat exchanger using the laminate material according to claim 1 or 2, wherein the piping member is made of a resin having a laser light transmittance of 10% or more. The heat exchanger using the laminate material according to any one of claims 1 to 3, wherein the material of the coating layer constituting the outer layer of the laminate material and the piping member are the same. Heat exchange using the laminate material according to any one of claims 1 to 4, wherein a flange member for improving the strength of the joint portion is provided along the inner peripheral surface of the laminate material in the vicinity of the entrance / exit. vessel. The heat exchanger using the laminate material according to claim 5, which has a fitting structure for determining a combination position of the piping member and the flange member. An in-vehicle battery module in which a heat exchanger using the laminate material according to any one of claims 1 to 6 and a battery unit are combined. A casing made of a laminate material provided with a resin coating layer on at least the outer surface side of the metal layer is provided, and a heat medium is allowed to flow in and out of the inside of the casing through an inlet / outlet penetrating the laminate material. In the method of manufacturing a heat exchanger using the laminated material
A piping member having a hole corresponding to the entrance / exit is provided outside the entrance / exit of the casing, and the piping member is made of a resin that transmits laser light, and the piping member and the laminating material are brought into contact with each other to bring the piping member into contact with each other. A laminating material characterized in that the coating layer constituting the outer layer of the laminating material and the piping member are joined to each other by laser welding due to the transmitted laser light generating heat in the metal layer is used. How to make a heat exchanger. The method for manufacturing a heat exchanger using the laminate material according to claim 8, wherein the laser beam passes through the outer wall and the lower wall of the piping member.

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