WO2023110183A1

WO2023110183A1 - Cooling plate

Info

Publication number: WO2023110183A1
Application number: PCT/EP2022/077575
Authority: WO
Inventors: Sergio Da Costa Pito; Guillaume GARDERE
Original assignee: Valeo Systemes Thermiques
Priority date: 2021-12-16
Filing date: 2022-10-04
Publication date: 2023-06-22
Also published as: FR3130951A1; FR3130951B1

Abstract

The invention relates to a cooling plate, in particular for cooling equipment that is likely to release heat during its functioning, said cooling plate having a first plate element (21), which is made of metal and is in particular substantially plane, and a second plate element (22), which in particular has concave shapes, these plate elements being joined together to form one or more flow channels (25) for a heat-exchange fluid, the second plate element having a body based on plastic material and, on this body, a covering based on carbon nanotubes, this covering being in contact with the first plate element (21).

Description

DESCRIPTION

TITLE OF THE INVENTION: COOLING PLATE

[1] |The present invention relates to a cooling plate, in particular for cooling equipment liable to release heat during its operation.

[2] The invention also relates to a compartment for equipment likely to release heat during its operation, in particular for an electrical energy storage device for a motor vehicle, and at least one cooling plate.

[3] Patent applications US2017176108 and WO 2013056938 describe heat exchangers for cooling battery cells. Furthermore, patent application US 2011/0206967 A describes an example of such a battery. In this application, the cells are stored in containers having housings for receiving the cells. A wall of the containers, intended to be in contact with a wall of a neighboring container, has recesses forming part of a conduit for the circulation of a heat transfer fluid.

[4] The invention aims to propose a new cooling plate that is lighter and has satisfactory robustness.

[5] The present invention thus relates to a cooling plate, in particular for cooling equipment liable to release heat during its operation, comprising a first metal plate element, which is in particular substantially planar, and a second element plate, in particular having concave shapes, these plate elements being assembled together to form one or more flow channels for a heat transfer fluid, the second plate element comprising a body based on plastic material and, on this body, a coating based on carbon nanotubes, this coating being in contact with the first plate element.

[6] Thanks to the invention, it is possible to reinforce the connection between the plate elements. Usually a connection between a metal part, for example in aluminium, and a plastic or composite plastic part does not have satisfactory mechanical cohesion. The invention, due to this coating in carbon nanotubes, allows better mechanical cohesion, without requiring any specific surface treatment on the aluminum plate element.

[7] In addition, the carbon nanotube coating increases the thermal conductivity of the second plate element, which improves heat exchange with the fluid circulating in the channel(s).

[8] The invention makes it possible to use a composite material based on plastic/polymer to produce the second plate element, which makes it possible to have an assembly that is lighter in weight.

[9] According to one aspect of the invention, the carbon nanotube coating covers an entire face of the second plate element.

[10] As a variant, the coating of carbon nanotubes covers only the junction zones between the two plate elements.

[11] According to one of the aspects of the invention, the nanotubes, in the coating, are oriented perpendicular to the plane of the plate.

[12] According to one of the aspects of the invention, the coating is formed by depositing, in particular by painting, the material forming the coating.

[13] Alternatively, the coating is formed by a film placed and fixed on the plastic-based body of the second plate element.

[14] According to one of the aspects of the invention, the body of the second plate element comprises a plastic base and at least one sheet of reinforcing material or fibers of reinforcing material, for example glass fibers or of carbon, embedded in the plastic base.

[15] According to one of the aspects of the invention, the second plate element comprises fibers of reinforcing material.

[16] According to one aspect of the invention, the plate elements are fixed together by heating the second plate element and pressing it against the first plate element, which creates cohesion between these plate elements . [17] According to one of the aspects of the invention, the second plate element has planar junction zones, in particular between the concavities, these planar junction zones being arranged to bear against the first plate element.

[18] According to one aspect of the invention, each channel is formed between the first plate element and a concavity of the second plate element.

[19] According to one aspect of the invention, each concavity forms one of the channels and extends between a fluid inlet and a fluid outlet.

[20] According to one aspect of the invention, the fluid inlet and outlet comprise orifices present on the second plate element.

[21] According to one of the aspects of the invention, the second plate element comprises a plurality of concavities forming a plurality of channels, for example two parallel flow channels.

[22] According to one aspect of the invention, these parallel channels extend between a common fluid inlet and a common fluid outlet.

[23] According to one aspect of the invention, at least one of the channels has a U-shape.

[24] According to one aspect of the invention, the two parallel channels each have a U-shape, one of the U-shapes being inside the other U-shape.

[25] According to one aspect of the invention, the channels have the same depth.

[26] In other words, in cross-section of the plate, the channels have the same depth measured from the first plate element to the opposite bottom of the channel on the second plate element.

[27] According to one aspect of the invention, the channels each have a flat bottom.

[28] According to one aspect of the invention, the channels occupy the major part of the second plate element. [29] Thus when looking at the plate in a direction perpendicular to the plate, the channels occupy most of the surface of the plate.

[30] Another subject of the invention is a compartment for equipment capable of releasing heat during its operation, the equipment being in particular an electrical energy storage device for a vehicle, this compartment comprising at least one housing arranged to receive said electrical equipment, and a cooling plate as described above, arranged to cool the equipment.

[31] The compartment may comprise a single or a plurality of such cooling plates.

[32] According to one aspect of the invention, the compartment has walls made of composite material based on plastic.

[33] The compartment may comprise a beam forming a side wall and a cover arranged to be assembled with the beam to close the housing, and the beam comprises a core made of composite material containing a plastic material and reinforcing elements, for example glass or carbon fiber.

[34] According to one aspect of the invention, the beam is hollow in the longitudinal direction.

[35] According to one aspect of the invention, each beam comprises one or more cavities resulting from the pultrusion.

[36] According to one aspect of the invention, these cavities are parallel to each other.

[37] According to one aspect of the invention, these cavities are one above the other in the direction of the height of the housing.

[38] According to one aspect of the invention, the cover is made from a plastic material.

[39] According to one aspect of the invention, the cover is made of a composite material containing a plastic material and reinforcing elements, for example glass or carbon fibers. [40] The cover and the beam can, if desired, be made of the same material.

[41] According to one aspect of the invention, the cover is arranged to rest on the beams forming the side wall of the housing.

[42] According to one of the aspects of the invention, the cooling plate is arranged in a bottom of the housing of the compartment so that the electrical equipment to be cooled rests on this plate, or these plates when the compartment has several .

[43] The invention also relates to an electrical energy storage module comprising a plurality of battery cells in particular arranged in a row, and a compartment as described above, the cells being placed in this compartment in thermal interaction with the cooling plate.

[44] This module is notably equipped with an electromagnetic protection function (also called CEM or Electromagnetic Compatibility).

[45] Other characteristics, details and advantages of the invention will emerge more clearly on reading the detailed description given below, and several embodiments given by way of indication and not limitation with reference to the appended schematic drawings of on the other hand, on which:

[46] [Fig.1] is a schematic view of a compartment according to an embodiment of the invention, in perspective,

[47] [Fig.2] represents a plate of the compartment of [Fig.1], in perspective,

[48] [Fig.3] is a schematic view of the second plate element of the plate of [Fig.2],

[49] [Fig.4] is a schematic and partial view, in section, of the plate of [Fig.2],

[50] [Fig.5] is a schematic and partial view of the second plate element.

[51] There is shown in Figure 1 an electrical energy storage module 100 comprising a plurality of battery cells 99, and a compartment 1.

[52] This compartment 1 comprises a housing 2 arranged to receive the electrical equipment, and, here, four beams 3 each forming a side wall 4 of this housing 2. [53] The compartment 1 further comprises a cover 5 arranged to be assembled with the beams 3 to close the housing 2.

[54] Each beam 3 comprises a core 7 made of a composite material containing a plastic material and reinforcing elements, here made of glass or carbon fibers.

[55] Each beam 3 is made by pultrusion, namely an extrusion by drawing, of the composite material.

[56] The composite material comprises continuous fibers of glass or carbon which serve as mechanical reinforcement. The pultrusion is carried out in the direction of these continuous fibers. The plastic matrix of the composite material is a thermoplastic or a thermoset. The plastic matrix is chosen from: a polyolefin, a polyamide, a polyester.

[57] Each beam 3 is hollow in the longitudinal direction of the beam concerned, and comprises several cavities 14 from the pultrusion. These cavities 14 are parallel to each other.

[58] These cavities 14 are one above the other, in the direction of the height of the housing.

[59] The cover 5 is made of a composite material containing a plastic material and reinforcing elements, for example glass or carbon fibers.

[60] The cover 5 is arranged to rest on the beams 3 forming the side wall of the housing.

[61] The compartment has a cooling plate 20.

[62] The cooling fluid which circulates in the cooling plate 20 can in particular be a liquid refrigerant based on carbon dioxide, such as R744 for example, 2, 3, 3, 3-tetrafluoropropene (or HFO-1234yf) or 1, 1, 1, 2-tetrafluoroethane (or R-134a). The coolant can also be a nanofluid. The coolant can still be water, possibly including additives.

[63] The cooling plate 20 forms a heat exchanger included in a cooling circuit, not shown, of the type comprising a compressor and other heat exchangers. [64] Battery cells 99 include, for example, a plurality of lithium-ion (Li-ion) batteries for use in a hybrid vehicle. In another embodiment, the plurality of battery cells are Li-ion batteries for use in a battery electric vehicle.

[65] As seen in Figures 2 to 5, the cooling plate 20 comprises a first metal plate element 21, which is substantially planar, and a second plate element 22, having concave shapes 23.

[66] These plate elements 21 and 22 are assembled together to form several flow channels 25 for a heat transfer fluid.

[67] The second plate element 22 comprises a body 26 made of plastic material and, on this body 26, a coating 27 based on carbon nanotubes, this coating 27 being in contact with the first plate element 21 .

[68] Thanks to the invention, it is possible to reinforce the connection between the plate elements 21 and 22.

[69] In addition, the coating 27 of carbon nanotubes makes it possible to increase the thermal conductivity of the second plate element 22, which improves heat exchange with the fluid circulating in the channel or channels.

[70] In the example described, the coating 27 of carbon nanotubes covers an entire face of the second plate element.

[71] Alternatively, the coating 27 of carbon nanotubes covers only the junction areas between the two plate elements 21 and 22.

[72] The nanotubes 29, in the coating 27, are oriented perpendicular to the plane of the plate. The nanotubes 29 are shown in exaggerated magnification in Figure 5.

[73] The coating 27 is formed by depositing, in particular by painting, the material forming the coating.

[74] Alternatively, the coating 27 is formed by a film placed and fixed on the body 26 of the second plate element 22. [75] The body 26 of the second plate element 22 comprises a plastic base and fibers of reinforcing material, for example glass or carbon fibers, embedded in the plastic base.

[76] The first and second plate elements 21 and 22 are fixed together by heating the second plate element 22 and pressing it against the first plate element 21, which creates the cohesion between these first and second plate elements .

[77] The second plate element 22 has flat junction areas 31 between the concavities 23, these flat junction areas 31 being arranged to bear against the first plate element 21.

[78] Each channel 25 is formed between the first plate element 21 and a concavity 23 of the second plate element 22.

[79] Each concavity 23 forms one of the channels 25 and extends between a fluid inlet 32 and a fluid outlet 33.

[80] The fluid inlet and outlet 32 and 33 have orifices present on the second plate element 22.

[81] The second plate element 22 comprises a plurality of concavities 23 forming a plurality of channels 25, here two channels 25 of parallel flow.

[82] These parallel channels 25 extend between a common fluid inlet 32 and a common fluid outlet 33.

[83] The two parallel channels 25 each have a U-shape, one of the U-shapes being inside the other U-shape.

[84] Channels 25 have the same depth here.

[85] In other words, in cross section of the plate as illustrated in Figure 4, the channels 25 have the same depth measured from the first plate element 21 to the opposite bottom 34 of the channel on the second plate element 22 .

[86] Channels 25 each have a flat bottom 34.

[87] The channels 25 occupy the major part of the second plate element 22. [88] Thus when looking at the plate 20 in a direction perpendicular to the plate, the channels 25 occupy most of the surface of the plate.

Claims

[Claim 1] Cooling plate (20), in particular for cooling equipment (99) capable of releasing heat during its operation, comprising a first plate element (21) made of metal, which is in particular substantially planar, and a second plate element (22), in particular having concave shapes (23), these plate elements being assembled together to form one or more flow channels (25) for a heat transfer fluid, the second plate element comprising a body ( 26) based on plastic material and, on this body, a coating (27) based on carbon nanotubes, this coating being in contact with the first plate element (21).

[Claim 2] Plate according to the preceding claim, in which the coating (27) of carbon nanotubes covers an entire face of the second plate element (22).

[Claim 3] Plate according to one of the preceding claims, in which the nanotubes, in the coating (27), are oriented perpendicular to the plane of the plate (20).

[Claim 4] Plate according to one of the preceding claims, in which the body of the second plate element (22) comprises a plastic base and fibers of reinforcing material, for example glass or carbon fibers, embedded in the plastic base.

[Claim 5] Plate according to one of the preceding claims, in which the second plate element (22) comprises planar junction zones (31), in particular between the concavities, these planar junction zones being arranged to be supported against the first plate element (21).

[Claim 6] Plate according to one of the preceding claims, in which the second plate element (22) comprises a plurality of concavities forming a plurality of channels (25), for example two parallel flow channels.

[Claim 7] Plate according to one of the preceding claims, in which at least one of the channels (25) has a U-shape.

[Claim 8] Plate according to the preceding claim in combination with claim 6, in which the two parallel channels (25) each have a U-shape, one of the U-shapes being inside the other U-shape. U.

[Claim 9] Plate according to one of the preceding claims 6 to 8, in which the channels (25) occupy the major part of the second plate element (22).

[Claim 10] Compartment for equipment capable of releasing heat during its operation, the equipment being in particular an electrical energy storage device for a vehicle, this compartment comprising at least one housing arranged to receive said electrical equipment, and a cooling plate (20) according to one of the preceding claims, arranged to cool the equipment.