Cooling device for an electrical arrangement

Abstract

Title: Cooling device for an electrical arrangement Cooling device for an electrical arrangement comprising: - a heat exchanger arranged 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 casing comprising a hollow face, an axis of the hollow face extending between a first zone of the casing intended to contain the electrical arrangement and a second zone of the casing intended to contain equipment whose temperature varies in a temperature range lower than a temperature of the heating point of the electrical arrangement, - a connection means between the second orifice of the heat exchanger and the hollow face of the casing, the hollow face of the casing containing arrangements allowing movement, towards the second zone of the casing,of air leaving the heat exchanger through the second orifice. Figure for abstract: 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 arrangement, such as a connection box of an electric battery, in particular 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 motorization means use increasingly efficient electric battery devices. In these battery devices, a connection box is generally linked on the one hand to the vehicle's traction system and on the other hand to the charging system. Rapidly recharging the battery of such a device requires high power (generally greater than 43kW) and a high current intensity (approximately 500 A). Such a current intensity can generate hot spots at the connection box. An excessive rise in temperatures can lead to malfunctions of the connection box, or even damage the electrical components of the connection box. Cooling of these components is therefore necessary to maintain the temperature of said hot spots below a single predefined temperature, 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 which 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 connection box of a battery of an electric or hybrid motor vehicle, comprising: - a heat exchanger arranged near a heating point of the electrical arrangement for its cooling, 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 arrangement and a second zone of the casing intended to contain equipment whose temperature varies in a range of temperatures lower than a temperature of the heating point of the electrical arrangement, 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 arrangements allowing movement, towards the second zone of the casing, of air leaving the heat exchanger through the second orifice.

[0005] The cooling device may comprise a means for sucking air contained in the second zone of the casing to blow it into the heat exchanger via the first air inlet orifice.

[0006] In one embodiment, the hollow face of the casing is delimited by an internal wall directed towards the inside of the casing and an external wall directed towards the outside of the casing, and the arrangements of the hollow face comprise a hole made on the internal wall allowing passage into the second zone of the casing 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 wall and the outer wall, or in a direction substantially perpendicular to the inner wall and the outer wall. In addition, the fins are intended to lengthen a path of air circulating in the hollow face, so as to increase a heat transfer between the air circulating in 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 casing and / or at least one side face of the casing extends parallel to the first axis.

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

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

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

[0013] Other details, characteristics and advantages will emerge more clearly on reading the detailed description given below, for informational and non-limiting purposes, in relation to the various exemplary embodiments illustrated in the following figures:

[0014] [Fig.l] 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 cover of the battery pack being absent.

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

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

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

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

[0020] [Fig.7] represents a cooling device according to the invention integrating 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 integrating 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 integrating two heat exchangers according to the third embodiment.

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

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

[0029] [Fig. 16] illustrates a heating of an air flow during its movement in an exchanger of the cooling device according to the invention.

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

[0031] [Fig. 18] illustrates an outlet of a cooled air flow from the hollow face through a hole opening onto the interior of the casing 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.l].

[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 arranged in a traction battery 1 is more specifically represented by FIGS. 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 - [Fig.3] illustrating a battery pack closed by a cover 13 and containing a cooling device according to the invention.

[0036] The electrical arrangement 11 comprises at least one heating point which needs to be cooled. For this purpose, the cooling device 2 according to the invention comprises - a heat exchanger 21 arranged 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 varies in a range of temperatures lower than 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 casing 22, the hollow face 221 of the casing 22 containing arrangements 2211 allowing movement, towards the second zone 223 of the casing, of air leaving the heat exchanger 21 through the second air outlet orifice 212.

[0037] In a preferred but non-limiting embodiment of the device 2, the casing 22 is a casing containing the traction battery 1. The casing 22 delimits an interior volume comprising two zones such that: - the first zone 222 is intended to contain the connection box 11 of the battery 1, and - the second zone 223 is intended to contain at least one module 12 of the battery 1.

[0038] In the remainder of the 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 elements of the motor vehicle 100 which are current consumers, in particular to connect the battery 1 to the traction motor or to the battery charging device. The box connection 11 fulfills a function of switching a connection between the battery 1 and the motor vehicle 100.

[0040] An embodiment of a connection box 11 is shown schematically 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 connections 114. In [Fig. 3], the connection box 11 is shown without the heat exchangers 21, in order to make the copper connections 114 visible. During rapid charging of the motor vehicle 100, the connections 114 have heating points 31 which must be cooled to avoid damaging the equipment. For this purpose, heat exchangers 21 are arranged in contact with the connections 114.

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

[0042] A connection means 23, illustrated by figures 7, 10 and 13, is arranged between the tube extending the second orifice 212 of the heat exchanger 21 and an opening 2216 of a hollow face 221 of the casing 22. In the embodiment presented, the connection means 23 is a sleeve made of insulating material which makes it possible to ensure 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 air flow 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. A 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 by Figures 5 to 7. In this embodiment, the housing 213 is parallelepipedal in shape. In addition, fins 214 are arranged in a thickness of the housing 213. An air flow enters through the first orifice 211, moves according to 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 by Figures 8 to 10. In this embodiment, the housing 213 is cylindrical in shape, the axis of the cylinder being directed in the direction XL. In the embodiment presented, 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 adjusted 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 along 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 pierced in its center, the axis of the cylinder being directed in the direction XL. A hollow fixing screw 215 is arranged in the drilling of the housing 213.

[0047] The hollow screw 215 includes arrangements, 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 perpendicular 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 interior 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 interior 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 leaves 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 casing 22 comprises two battery modules 12. The temperature of the modules 12 varies in a temperature range lower than the temperature of the heating point 31 of the connection box 11.

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

[0051] In one embodiment, the hollow face 221 is produced by extrusion. In a preferred embodiment, the hollow face 221 comprises an inner wall 2212 and an outer wall 2213 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 movement towards the second zone 223 of the casing of air leaving the heat exchanger 21 via the second air outlet orifice 212, comprise the free space 2214 and optionally fins 2215 (also called baffles 2215) described later in this document.

[0053] A connection means 23 is arranged between the second orifice 212 of the heat exchanger 21 and the hollow face 221. The connection means 23 makes it possible to convey hot air leaving the heat exchanger 21 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 polymer. Indeed, this makes it possible to prevent the passage of an electric current between the casing 22 and the heat exchanger 21.

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

[0057] In addition, the internal wall 2212 comprises a second through hole 2217 preferably located in the second zone 223 of the casing.

[0058] Thus, the hollow face 221 is capable of allowing circulation of air taken from the outlet of the heat exchanger 21 via 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 casing 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 internal wall 2212 and to the external wall 2213, as illustrated by [Fig. 14], - or in a direction substantially parallel to the internal wall 2212 and to the external wall 2213, as illustrated by [Fig. 15].

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

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

[0063] Thus, when the suction means is activated, the cooling device 2 initiates and maintains a circulation of air in the casing 22, the course of the circulation comprising the following steps, described with reference to FIGS. 16 to 18, - a first step E1 of suction of air from the second zone 223 of the casing by the suction means, the air of the second zone being at a first temperature T1 significantly lower than a temperature T0 measured at a heating point 31 of the connection box 3, - a second step E2 of injecting, by the suction means 24, air at temperature T1 into the heat exchanger 21 via the first orifice 211, - a third step E3 of circulating the air in the heat exchanger 21 and heating the air to a second temperature T2 (higher than the first temperature T1) by heat exchange with a heating point 31 of the connection box 3, - a fourth step E4 of injecting into the hollow face 221 air from the heat exchanger 21, the temperature of the air being equal to the second temperature T2 reached during the third step, - a fifth step E5 of circulating the air in the free space 2214 of the hollow face 221, and of cooling the air to a third temperature T3 (lower than the second temperature T2) by heat exchange with the external wall 2213, - a sixth step E6 of reinjection, into the second zone 223 of the casing, of the air cooled during the fifth step.

[0064] Different embodiments of the hollow face 221 are possible. The hollow face 221 may be a lower face 224 of the casing, intended to be placed under the battery modules 12, or a lateral face 225 of the casing extending in the direction XI, that is to say a lateral upright 225 of the casing which runs along 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 orifice 212 connected to a hollow face 221 taken from a lower face 224 or a lateral face 225 of the housing. Advantageously, a heat exchanger is arranged near each heating point of the connection housing 11.

[0066] Conduits 41 of a cooling circuit 4 of the modules 12 may advantageously be arranged in at least one hollow face 221 of the casing. In this case, the fifth step E5 of circulation of the air in the hollow face 221 comprises cooling of the air 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 heating points of the connection box by using the hollow faces of the battery casing to cool air from the heat exchangers arranged 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 it is then cooled by thermal conduction in contact with the external wall of the at least one hollow face. Furthermore, the air can also be cooled by a cooling circuit arranged 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 connection means between an outlet orifice of a heat exchanger and a first hole made in an internal wall of a hollow casing face, 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

Claims

1. Cooling device (2) for an electrical arrangement (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) arranged 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 battery casing, 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 varies in a temperature range lower than a temperature of the heating point (31) of the electrical arrangement (11),the second zone (223) of the casing being intended in particular 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 casing (22), the hollow face (221) of the casing containing arrangements (2211) allowing movement, towards the second zone (223) of the casing, of air leaving the heat exchanger (21) via the second orifice (212).,

2. Cooling device (2) according to the preceding claim, characterized in that it comprises a means (24) for sucking air contained in the second zone (223) of the casing to blow it into the heat exchanger (21) via the first air inlet orifice (211).

3. Cooling device (2) according to one of the preceding claims, the hollow face (221) of the casing being delimited by an internal wall (2212) directed towards the inside of the casing and an external wall (2213) directed towards the outside of the casing, characterized in that the arrangements (2211) of the hollow face (221) comprise a hole (2216) made on the internal wall (2212) allowing a passage in the second zone (223) of the casing of air circulating between the internal wall (2212) and the external 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 to the outer wall (2213), or in a direction substantially perpendicular to the inner wall (2212) and to 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 a 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 one of the preceding claims, characterized in that the hollow face (221) is produced by extrusion.

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

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

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

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