Cooling device for an electrical arrangement

Abstract

Title: Cooling device for an electrical arrangement. Cooling device for an electrical arrangement comprising: - a heat exchanger disposed near a heating point of the electrical arrangement, air circulating in the heat exchanger between a first air inlet and a second air outlet, - a housing comprising a hollow face, an axis of the hollow face extending between a first zone of the housing intended to contain the electrical arrangement and a second zone of the housing intended to contain equipment whose temperature varies within a range of temperatures lower than the heating point temperature of the electrical arrangement, - a connection means between the second orifice of the heat exchanger and the hollow face of the housing, the hollow face of the housing containing features allowing movement towards the second zone of the housing.of air exiting the heat exchanger through the second orifice. Figure for the abbreviation: Figure 7,

Description

Title of the invention: Cooling device for an electrical arrangement

[0001] The present invention relates to a cooling device for an electrical assembly, such as a battery connection box, particularly for an electric or hybrid motor vehicle. The invention further relates to an electric or hybrid vehicle equipped with such a cooling device.

[0002] In electric or hybrid vehicles, current electric drive systems utilize increasingly efficient electric battery devices. In these battery devices, a junction box is generally connected to the vehicle's traction system on one side and to the charging system on the other. Rapidly recharging the battery in such a device requires high power (generally exceeding 43 kW) and a high current intensity (approximately 500 A). Such a high current intensity can generate hot spots in the junction box. Excessive temperature increases can lead to malfunctions in the junction box, or even damage to its electrical components. Cooling of these components is therefore necessary to maintain the temperature of these hot spots below a predefined threshold, in particular below 150 degrees Celsius.

[0003] The present invention falls within this context and aims to provide an efficient and economical cooling solution. An objective of the invention is therefore to provide an efficient and economical cooling device that precisely targets the hot spots of the connection box to keep them below a maximum temperature.

[0004] To this end, the invention proposes a cooling device for an electrical arrangement, in particular for a battery connection box of an electric or hybrid motor vehicle, comprising: - a heat exchanger disposed near a heating point of the electrical assembly for its cooling, with air circulating in the heat exchanger between a first air inlet and a second air outlet, - a casing, in particular a battery casing, comprising a hollow face, a first axis of the hollow face extending between a first zone of the casing intended to contain the electrical assembly and a second zone of the casing intended to contain equipment whose temperature varies within a range of temperatures lower than a temperature of the heating point of the electrical assembly, the second zone of the casing being in particular intended to contain at least one battery module, - a means of connection between the second orifice of the heat exchanger and the hollow face of the casing, the hollow face of the casing containing features allowing the movement of air exiting the heat exchanger through the second orifice towards the second zone of the casing.

[0005] The cooling device may include a means of drawing air contained in the second zone of the housing to blow it into the heat exchanger via the first air inlet port.

[0006] In one embodiment, the hollow face of the housing is delimited by an internal wall directed towards the inside of the housing and an external wall directed towards the outside of the housing, and the arrangements of the hollow face include a hole made on the internal wall allowing passage into the second zone of the housing of air circulating between the internal wall and the external wall.

[0007] In one embodiment, the hollow face contains fins, in particular arranged either in a direction substantially parallel to the inner and outer walls, or in a direction substantially perpendicular to the inner and outer walls. Furthermore, the fins are designed to lengthen the path of air circulating within the hollow face, so as to increase heat transfer between the air circulating within the hollow face and the outer wall of the hollow face.

[0008] In one embodiment, the hollow face is produced by extrusion.

[0009] In one embodiment, the hollow face is a lower face of the housing and / or the less one lateral face of the casing extends parallel to the first axis.

[0010] In one embodiment, conduits of a cooling circuit for the equipment are arranged in the hollow face.

[0011] In one embodiment, the heat exchanger is fixed to a copper connection of the electrical arrangement.

[0012] The invention also relates to an electric or hybrid motor vehicle comprising a cooling device according to the invention.

[0013] Other details, features and advantages will become clearer upon reading the detailed description given below, by way of example and not limitation, in relation to the various embodiments illustrated in the following figures:

[0014] Fig. 1 is a schematic representation of a cooling device according to the invention.

[0015] Fig. 2 illustrates a first embodiment of a cooling device according to the invention integrated into a battery pack, the battery pack cover being absent.

[0016] Figure 3 illustrates a closed battery pack containing a cooling device according to the invention.

[0017] Fig. 4 is a simplified representation of a traction battery connection box.

[0018] Fig. 5 illustrates a first embodiment of a heat exchanger of the cooling device according to the invention.

[0019] Figure 6 illustrates a variant of the first embodiment of a heat exchanger of the cooling system according to the invention.

[0020] Figure 7 represents a cooling device according to the invention incorporating two heat exchangers according to the first embodiment.

[0021] Fig. 8 is a first view of a second embodiment of a heat exchanger of the cooling device according to the invention.

[0022] Fig. 9 is a second view of the second embodiment of a heat exchanger of the cooling system according to the invention.

[0023] Fig. 10 represents a cooling device according to the invention incorporating two heat exchangers according to the second embodiment.

[0024] Fig. 11 is a first view of a third embodiment of a heat exchanger of the cooling device according to the invention.

[0025] Fig. 12 is a second view of the third embodiment of a heat exchanger of the cooling system according to the invention.

[0026] Fig. 13 represents a cooling device according to the invention incorporating two heat exchangers according to the third embodiment.

[0027] Fig. 14 illustrates a first embodiment of a hollow face of a housing of the cooling device according to the invention.

[0028] Fig. 15 illustrates a second embodiment of a hollow face of a housing of the cooling device according to the invention.

[0029] Fig. 16 illustrates the heating of an airflow as it moves through an exchanger of the cooling device according to the invention.

[0030] Fig. 17 illustrates the cooling of the airflow as it moves through a hollow face of a housing of the cooling device according to the invention.

[0031] Fig. 18 illustrates an outlet of a cooled airflow from the hollow face through a hole opening onto the inside of the housing of the cooling device according to the invention.

[0032] An embodiment of a motor vehicle 100 equipped with the invention is described with reference to [Fig.1].

[0033] The motor vehicle 100 is an electric or hybrid vehicle, equipped with a traction battery 1.

[0034] The motor vehicle 100 is equipped with a cooling device 2 according to the invention, for cooling an electrical arrangement 11, in particular for cooling a connection box 11 of the traction battery 1.

[0035] A cooling device 2 disposed in a traction battery 1 is more specifically represented by Figures 2 and 3, - [Fig. 2] illustrating a first embodiment of a cooling device according to the invention integrated into a battery pack, the cover 13 of the battery pack being absent, and - the [Fig.3] illustrating a battery pack closed by a lid 13 and containing a cooling device according to the invention.

[0036] The electrical arrangement 11 includes at least one heating point that requires cooling. For this purpose, the cooling device 2 according to the invention comprises - a heat exchanger 21 disposed near a heating point 31 of the electrical arrangement 11 for its cooling, air circulating in the heat exchanger 21 between a first air inlet orifice 211 and a second air outlet orifice 212, - a casing 22, in particular a casing 22 of the traction battery 1, comprising a hollow face 221, a first axis XI of the hollow face 221 extending between a first zone 222 of the casing intended to contain the electrical arrangement 11 and a second zone 223 of the casing intended to contain equipment 12 whose temperature evolves in a range of temperatures below a temperature of the heating point of the electrical arrangement, the second zone 223 of the casing being in particular intended to contain at least one battery module 12, - a connection means 23 between the second orifice 212 of the heat exchanger 21 and the hollow face 221 of the housing 22, the hollow face 221 of the housing 22 containing features 2211 allowing a movement, towards the second zone 223 of the housing, of air exiting the heat exchanger 21 through the second air outlet orifice 212.

[0037] In a preferred but not limiting embodiment of device 2, the housing 22 is a housing containing the traction battery 1. The housing 22 delimits an internal volume comprising two zones such as: - the first zone 222 is intended to contain the connection box 11 of battery 1, and - the second zone 223 is intended to contain at least one module 12 of battery 1.

[0038] In the remainder of this document, the terms "connection box 11" and "electrical arrangement 11" are used interchangeably. Similarly, the terms "equipment 12", "at least one module 12" and "module 12" are used interchangeably.

[0039] The role of the connection box 11 is to connect the battery 1 to the various components of the motor vehicle 100 that consume current, in particular to connect the battery 1 to the traction motor or the battery charging device. The box connection 11 performs a switching function for a link between battery 1 and motor vehicle 100.

[0040] An embodiment of a connection box 11 is schematically represented in Figures 2 and 3. Only equipment capable of generating a heating point 31 is shown, in particular a pyroswitch 111 (also called a network switch 111 or controllable fuse 111), a relay 112, and a fuse 113, these elements being electrically connected to each other by copper links 114. In [Fig. 3], the connection box 11 is shown without the heat exchangers 21, in order to make the copper links 114 visible. During rapid charging of the motor vehicle 100, the links 114 exhibit heating points 31 that must be cooled to prevent damage to the equipment. For this purpose, heat exchangers 21 are arranged in contact with the links 114.

[0041] In a first and a second embodiment, the heat exchanger 21 comprises a housing 213, a first air inlet port 211 in the housing 213, and a second air outlet port 212 from the housing 213. The first and second ports 211, 212 are each advantageously extended by a straight tube connecting the first port 211 to an air inlet, and connecting the second port 212 to an air outlet. The relative arrangement of the tubes extending from the first and second ports 211, 212 may vary. The tubes may be arranged in the same direction, as illustrated in Figures 5 and 8. Alternatively, the tubes may be perpendicular to each other, as illustrated in Figures 6 and 9.

[0042] A connection means 23, illustrated by figures 7, 10 and 13, is disposed between the tube extending from the second orifice 212 of the heat exchanger 21 and an opening 2216 of a hollow face 221 of the housing 22. In the embodiment presented, the connection means 23 is a sleeve made of insulating material which makes it possible to ensure an infinite electrical resistance between the second orifice 212 of the heat exchanger 21 and the opening 2216 of the hollow face.

[0043] In the first and second embodiments presented below, an airflow enters through the first orifice 211, moves along a circuit defined by the fins 214 of the heat exchanger 21, and exits through the second orifice 212. Heat exchange takes place between the air circulating in the housing 213 and a heating point 31 near which the heat exchanger 21 is fixed.

[0044] The first embodiment of a heat exchanger 21 is illustrated in Figures 5 to 7. In this embodiment, the casing 213 is parallelepiped in shape. Furthermore, fins 214 are provided within a thickness of the casing 213. An airflow enters through the first orifice 211 and moves along a circuit defined by the fins 214, and exits through the second orifice 212. The heat exchange is thus maximized by the presence of the fins 214.

[0045] The second embodiment of a heat exchanger 21 is illustrated in Figures 8 to 10. In this embodiment, the housing 213 is cylindrical, with the axis of the cylinder directed along the XL direction. In the embodiment shown, the cylinder formed by the housing 213 is truncated by a flat 216. The flat 216 is advantageously parallel to the axis of the cylinder. The housing 213 contains an insert 217 whose shape is adapted to fit into the truncated cylinder formed by the housing 213. Fins 214 are advantageously arranged on the insert 217. Advantageously, the fins 214 extend in planes perpendicular to the axis of the cylinder.

[0046] A third embodiment of a heat exchanger 21 is illustrated by figures 11 to 13. In this embodiment, the heat exchanger 21 comprises a cylindrical housing 213 with a hole in its center, the axis of the cylinder being directed along the direction XL. A hollow fixing screw 215 is disposed in the hole in the housing 213.

[0047] The hollow screw 215 includes features, in particular - a first bore 2151 passing through the hollow screw 215 along its longitudinal axis, and - a second bore 2152 passing through the screw perpendicularly to the first bore 2151. The first and second bores 2151, 2152 of the hollow screw communicate with each other, and the second bore communicates with an internal volume 2131 of the cylindrical housing 213.

[0048] Thus, in the third embodiment of the heat exchanger 21, the air enters the exchanger through a first orifice 211 arranged on the housing 213, the air is then directed into the internal volume 2131 of the cylindrical housing 213 for its cooling, then the air enters the hollow screw 215 through the second bore 2152, then the air passes through the hollow screw 215 through the first bore 2151 and the air exits the exchanger 21 through the end 212 of the first bore 2151.

[0049] As can be seen in [Fig. 2], the second zone 223 of the housing 22 comprises two battery modules 12. The temperature of the modules 12 varies within a range of temperatures lower than the temperature of the heating point 31 of the connection box 11.

[0050] The hollow face 221 is arranged so as to run successively along the connection box 11 and at least one module 12.

[0051] In one embodiment, the hollow face 221 is formed by extrusion. In a preferred embodiment, the hollow face 221 comprises an internal wall 2212 and an external wall 2213 that are substantially parallel to each other and separated by a free space 2214.

[0052] Said arrangements 2211 of the hollow face 221, which are intended to allow a movement towards the second zone 223 of the housing of air exiting the heat exchanger 21 through the second air outlet orifice 212, include the free space 2214 and optionally fins 2215 (also called baffles 2215) described later in this document.

[0053] A connection means 23 is disposed between the second orifice 212 of the heat exchanger 21 and the hollow face 221. The connection means 23 allows hot air exiting the heat exchanger 21 to be conveyed into the free space 2214.

[0054] In one embodiment, the connection means 23 is a pipe 23 or sleeve 23 of which - a first end 231 is hermetically connected to the second orifice 212 of the heat exchanger, and - a second end 232 is hermetically connected to a first through hole 2216 made on the internal wall 2212 of the hollow face.

[0055] Advantageously, the pipe 23 is made of an electrically insulating material, in particular a polymer. Indeed, this prevents the passage of an electric current between the housing 22 and the heat exchanger 21.

[0056] The first through hole 2216 is advantageously located in the first zone 222 of the housing.

[0057] In addition, the inner wall 2212 includes a second through hole 2217 located preferably in the second zone 223 of the housing.

[0058] Thus, the hollow face 221 is suitable for allowing the circulation of air taken from the outlet of the heat exchanger 21 by means of the pipe 23 connected to the first through hole 2216, the air being conveyed through the free space 2214, and the air opening into the second zone 223 of the housing via the second through hole 2217.

[0059] A heat exchange then takes place between the air circulating in the free space 2214 and the external wall 2213. Advantageously, an air movement circuit can be created in the free space 2214, in particular by fins 2215.

[0060] Indeed, as illustrated by Figures 14 and 15, in one embodiment of the invention, the hollow face 221 contains fins 2215, in particular arranged - either in a direction substantially perpendicular to the inner wall 2212 and the outer wall 2213, as illustrated by [Fig. 14], - or in a direction substantially parallel to the inner wall 2212 and the outer wall 2213, as illustrated by [Fig. 15].

[0061] The fins are intended to lengthen the path of air circulating in the hollow face, so as to increase heat transfer between the air circulating in the hollow face and the outer wall 2213 of the hollow face 221.

[0062] In a preferred embodiment, the cooling device 2 includes a means 24 for drawing air contained in the second zone 223 of the housing to blow it into the heat exchanger 21 via the first air inlet port 211 of the heat exchanger 21. The drawing means may be an air blower 24.

[0063] Thus, when the suction means is activated, the cooling device 2 initiates and maintains an air circulation in the housing 22, the course of the circulation comprising the following steps, described with reference to Figures 16 to 18, - a first step El of suction of air from the second zone 223 of the housing by the suction means, the air from the second zone being at a first temperature Tl significantly lower than a temperature T0 measured at the level of a heating point 31 of the connection box 3, - a second stage E2 of injection, by means of suction 24, of air at temperature Tl into the heat exchanger 21 via the first orifice 211, - a third stage E3 of circulation of the air in the heat exchanger 21 and of heating of the air to a second temperature T2 (higher than the first temperature Tl) by heat exchange with a heating point 31 of the connection box 3, - a fourth step E4 of injecting air from the heat exchanger 21 into the hollow face 221, the air temperature being equal to the second temperature T2 reached during the third step, - a fifth stage E5 of air circulation in the free space 2214 of the hollow face 221, and of air cooling down to a third temperature T3 (lower than the second temperature T2) by heat exchange with the external wall 2213, - a sixth stage E6 of reinjection, in the second zone 223 of the crankcase, of the air cooled during the fifth stage.

[0064] Different embodiments of the hollow face 221 are possible. The hollow face 221 can be a lower face 224 of the housing, intended to be placed under the battery modules 12, or a lateral face 225 of the housing extending along the direction XI, i.e. a lateral upright 225 of the housing which runs alongside both the connection box 11 and at least one battery module 12.

[0065] In one embodiment, the device 2 may comprise several heat exchangers 21, each heat exchanger 21 comprising a second air outlet 212 connected to a hollow face 221 taken from a lower face 224 or a side face 225 of the housing. Advantageously, a heat exchanger is disposed near each heating point of the connection housing 11.

[0066] Conduits 41 of a cooling circuit 4 of the modules 12 can advantageously be arranged in at least one hollow face 221 of the housing. In this case, The fifth stage E5 of air circulation in the hollow face 221 includes air cooling by heat exchange with the cooling circuit 4. In other words, in this embodiment, the cooling device 2 takes advantage of the presence of a cooling circuit intended for cooling the modules 12.

[0067] Finally, the cooling device 2 according to the invention improves the efficiency of cooling the hot spots of the connection box by using the hollow faces of the battery casing to cool air from the heat exchangers located on the connection box. The air heated by the heat exchangers of the connection box circulates in at least one hollow face of the casing, and is then cooled by thermal conduction through contact with the outer wall of at least one hollow face. Furthermore, the air can also be cooled by a cooling circuit located in the hollow face and intended for cooling the battery modules.

[0068] The implementation of the invention is inexpensive, since it simply requires, firstly, adding a means of connection between an outlet orifice of a heat exchanger and a first hole made in an internal wall of a hollow face of a housing, and - secondly, to make a second hole in the internal wall of the hollow face to reinject the cooled air into the casing, particularly near the battery modules.

Claims

Demands

1. A cooling device (2) for an electrical assembly (11), in particular for a connection box (11) of a battery (1) of an electric or hybrid motor vehicle, characterized in that it comprises: - a heat exchanger (21) disposed near a heating point (31) of the electrical assembly (11) for its cooling, air circulating in the heat exchanger (21) between a first air inlet orifice (211) and a second air outlet orifice (212), - a housing (22), in particular a battery housing, comprising a hollow face (221), a first axis (XI) of the hollow face (221) extending between a first zone (222) of the housing intended to contain the electrical assembly (11) and a second zone (223) of the housing intended to contain equipment (12) whose temperature varies within a temperature range below a heating point temperature (31) of the electrical arrangement (11),the second zone (223) of the housing being specifically intended to contain at least one battery module (12), - a connection means (23) between the second orifice (212) of the heat exchanger (21) and the hollow face (221) of the housing (22), the hollow face (221) of the housing containing features (2211) allowing the movement of air exiting the heat exchanger (21) through the second orifice (212) towards the second zone (223) of the housing.

2. Cooling device (2) according to the preceding claim, characterized in that it comprises a means for drawing in air contained in the second zone (223) of the housing to blow it into the heat exchanger (21) via the first air inlet orifice (211).

3. A cooling device (2) according to any one of the preceding claims, the hollow face (221) of the housing being delimited by an inner wall (2212) directed towards the interior of the housing and an outer wall (2213) directed towards the exterior of the housing, characterized in that the arrangements (2211) of the hollow face (221) comprise a hole (2216) formed on the inner wall (2212) allowing passage in the second zone (223) of the crankcase of air circulating between the inner wall (2212) and the outer wall (2213).

4. Cooling device (2) according to the preceding claim, characterized in that the hollow face (221) contains fins (2215), in particular arranged either in a direction substantially parallel to the inner wall (2212) and the outer wall (2213), or in a direction substantially perpendicular to the inner wall (2212) and the outer wall (2213), and in that the fins are intended to lengthen a path of air circulating in the hollow face (221), so as to increase heat transfer between the air circulating in the hollow face (221) and the outer wall (2213) of the hollow face (221).

5. Cooling device according to any one of the preceding claims, characterized in that the hollow face (221) is made by extrusion.

6. Cooling device according to any one of the preceding claims, characterized in that the hollow face (221) is a lower face (224) of the housing and / or at least one lateral face (225) of the housing extending parallel to the first axis (XI).

7. Cooling device according to any one of the preceding claims, characterized in that conduits (41) of a cooling circuit (4) of the equipment (12) are arranged in the hollow face (221).

8. Cooling device according to any one of the preceding claims, characterized in that the heat exchanger (21) is fixed on a copper link (114) of the electrical arrangement (11).

9. Motor vehicle (1) with electric or hybrid powertrain comprising a cooling device (2) according to any one of the preceding claims.

Images