Heat dissipation device and electrical connection box, electrical energy storage device, in particular a storage battery, and / or a motor vehicle comprising such a heat dissipation device

Abstract

The invention relates to a heat dissipation device, in particular for a motor vehicle, the device being configured for heat exchange between a hot source (12) comprising an electrical member (14) and a cold source (16), the device comprising a first thermal interface member (18), intended to be at an electrical potential substantially identical to an electrical potential of the electrical member (14), the first thermal interface member (18) being configured to conduct heat from the hot source (12) in the direction of the cold source (16), the device further comprising a first housing (20) containing a dielectric fluid, the first housing being configured to establish a heat exchange between the first thermal interface member (18) and the cold source (16).

Description

[0001] Heat dissipation device as well as electrical connection box, electrical energy storage device, including accumulator battery, and / or motor vehicle including such a heat dissipation device

[0002] The invention relates to a heat dissipation device, particularly for a motor vehicle. It also relates to an electrical connection box for an electrical energy storage device, particularly a battery, comprising such a dissipation device. It further relates to said electrical energy storage device, comprising such an electrical connection box and / or such a dissipation device. It also relates to a motor vehicle comprising such a storage device, such a box, and / or such a dissipation device.

[0003] In this field, it is known that electric or hybrid vehicles equipped with a battery pack include a casing that houses several electrochemical cells connected together and providing a high voltage at the battery terminals, typically a voltage of several hundred volts.

[0004] It is then necessary to equip the battery with an electrical connection box containing safety electrical components (relays, fuses) in order to cut off the current when needed. These components are connected using busbars through which the battery's input or output current flows.

[0005] In certain situations, the battery supplies or receives a high electrical power. This is the case, for example, during so-called fast charging of the vehicle's battery, or when the vehicle must exert significant traction. In these situations, the flow of a high-intensity current generates a sharp increase in temperature, particularly in areas commonly referred to as "hot spots," such as safety-critical electrical components, which then present an increased risk of degradation. To mitigate this risk, it is common practice to oversize these components. However, this results in significant bulk, an excessive increase in weight, and a higher cost.

[0006] The invention aims to overcome at least in part the previous drawbacks and proposes to this end a heat dissipation device, in particular for motor vehicles, said device being configured for heat exchange between, on the one hand, a hot source comprising an electrical component, and, on the other hand, a cold source, said device comprising a first thermal interface component, intended to be at an electrical potential substantially identical to an electrical potential of said electrical component, said first thermal interface component being configured for heat conduction from the hot source towards the cold source, said device further comprising a first housing containing a dielectric fluid, said first housing being configured to establish heat exchange between said first thermal interface component and said cold source.

[0007] This heat dissipation device improves the cooling of the electrical component, thus preventing oversizing. Furthermore, the housing acts as a spacer between the first live thermal interface component and the insulated cold source. This limits the risk of unwanted contact between the live and insulated components, even in the event of shocks.

[0008] According to various additional features of the invention, which may be taken together or separately and which constitute so many embodiments of the invention:

[0009] - said device further includes a heat pipe for said heat exchange between the hot source and the cold source,

[0010] - said first thermal interface element has a first heat exchange surface in contact with said heat pipe,

[0011] - said first thermal interface element comprises a sleeve housing said heat pipe and forming said first exchange surface,

[0012] - said first thermal interface element is configured to be in contact with said first housing and / or said dielectric fluid,

[0013] - said first housing comprises an electrically insulating frame and a contact wall, said contact wall being thermally conductive and disposed opposite said first thermal interface element with respect to said frame so that said contact wall and said first thermal interface element are electrically insulated from each other,

[0014] - said framework, said contact wall and said first thermal interface element together define a housing for said fluid,

[0015] - said contact wall is intended to be in a heat exchange relationship with said cold source,

[0016] - said contact wall comprises a closing part of said housing and a part forming a diffusion plate, intended to be opposite said cold source,

[0017] - said diffusion plate has a larger surface area compared to said closing part,

[0018] - said contact wall is made of copper, copper alloy, aluminum and / or aluminum alloy,

[0019] - said frame is made of plastic material, in particular polymer material and / or ABS.

[0020] - said first thermal interface element is made of copper, copper alloy, aluminum and / or aluminum alloy,

[0021] - said first thermal interface element, referred to as the cold element, is configured for heat exchange between said heat pipe and said cold source via said first housing,

[0022] - said device includes a second thermal interface element, referred to as the hot element, for heat exchange between said heat pipe and the other of said hot or cold sources,

[0023] - said second thermal interface element, said hot, is configured for heat exchange between said heat pipe and said hot source.

[0024] The invention also relates to an electrical connection box, for example for an electrical energy storage device, particularly a battery. Said connection box comprises a cold source and a hot source equipped with an electrical component, said connection box further comprising a heat dissipation device as described above for heat conduction between said hot and cold sources. According to various additional features of the invention, which may be considered together or separately and which constitute so many embodiments of the invention:

[0025] - said electrical component includes an electrical protection component,

[0026] - said electrical protection device includes an electrical relay,

[0027] - said electrical component includes a second housing with electrical connection terminals,

[0028] - said connection box includes electrical conduction busbars,

[0029] - said electrical conduction bars are respectively connected to said electrical connection terminals,

[0030] - said bus bars are sandwiched between said second housing and said second thermal interface element,

[0031] - said cold source comprises a plate exhibiting a thermal inertia much greater than that of said heat source,

[0032] - said plate includes all or part of a lower face of a casing of the electrical energy storage device.

[0033] The invention also relates to an electrical energy storage device, in particular a battery of accumulators, comprising a connection box and / or heat dissipation device as described above.

[0034] The invention further relates to a vehicle comprising an electrical energy storage device, a connection box and / or a heat dissipation device as described above.

[0035] The invention will be better understood, and other objects, details, features and advantages thereof will become more apparent in the course of the detailed explanatory description which follows, of at least one embodiment of the invention given by way of purely illustrative and non-limiting example, with reference to the accompanying schematic drawings, among which:

[0036] [Fig 1] schematically illustrates, in side view, a motor vehicle comprising a connection box according to the invention;

[0037] [Fig 2] schematically and partially illustrates a connection box including an example of a heat dissipation device according to the invention; [Fig 3] schematically illustrates, in perspective, in exploded view, the heat dissipation device of figure 2;

[0038] [Fig 4] schematically illustrates in perspective, in assembled mode, the heat dissipation device of figure 3;

[0039] [Fig 5] schematically illustrates in longitudinal section view the heat dissipation device of figure 4.

[0040] It should first be noted that the terms "first", "second", "third", ... are only used to distinguish the components concerned from each other and do not imply any order or possible importance of said components.

[0041] The invention relates to a heat dissipation device, particularly for motor vehicles.

[0042] As illustrated in Figure 1, the invention also relates to an electrical connection box 1, an electrical energy storage device 2, in particular a battery, and a vehicle V comprising such a heat dissipation device. The latter is placed, for example, in the electrical connection box 1, said connection box 1 being used here to electrically connect said electrical energy storage device 2 to an electrical network 3 of the motor vehicle V. Said vehicle V is advantageously an electric or hybrid vehicle connected to said electrical network 3.

[0043] As illustrated in Figure 2, said heat dissipation device, identified as 10 in this figure, is configured for heat exchange between, on the one hand, a hot source 12 comprising an electrical component 14, and, on the other hand, a cold source 16. This allows said electrical component 14 to be cooled and thus avoids its oversizing.

[0044] The dissipation device comprises a first thermal interface element 18. This first thermal interface element 18 is intended to be at an electrical potential substantially identical to that of the electrical element 14. This first thermal interface element 18 is further configured for heat conduction from the hot source 12 towards the cold source 16. This first thermal interface element 18 increases the heat exchange surfaces in contact. According to the invention, the device further comprises a first housing 20 containing a dielectric fluid to establish heat exchange between this first thermal interface element 18 and this cold source 16.

[0045] The first housing 20 thus forms a spacer between the first live thermal interface element 18 and the insulated cold source 16. This limits the risk of unwanted contact between the live and insulated elements, even in the event of shocks. It is understood that the first housing 20 is configured to provide electrical insulation between the first thermal interface element 18 and the cold source 16, with the heat flow passing through the dielectric fluid.

[0046] Preferably, the device further comprises a heat pipe 22 for heat exchange between the hot source 12 and the cold source 16. This further improves heat exchange. The heat pipe 22 is straight. It may, for example, have a rounded cross-section, particularly a circular one. The heat pipe 22 is, in particular, sintered and / or grooved.

[0047] As more clearly seen in the following figures, in the illustrated embodiment, the first thermal interface element 18 has a first heat exchange surface 18a in contact with the heat pipe 22. The first thermal interface element 18 here comprises a sleeve 24 housing the heat pipe 22 and forming the first heat exchange surface 18a. The first thermal interface element further comprises a body 23. The first sleeve 24 is, for example, continuous with the body 23. The first thermal interface element 18 here has radial shapes flaring out from the first sleeve 24 towards the body 23 to promote heat conduction.

[0048] The said first thermal interface element 18 is configured to be in contact, at least thermally, with said first housing 20 and / or said dielectric fluid, in particular through its body 23.

[0049] The first housing 20 comprises an electrically insulating armature 26 and a contact wall 28. The contact wall 28 is thermally conductive and disposed opposite the first thermal interface element 18 with respect to the armature 16 so that the contact wall 28 and the first thermal interface element 18 are electrically insulated from each other.

[0050] The said frame 26, the said contact wall 28 and the said first thermal interface element 18 together define a housing 30 for the said fluid. Advantageously, the said contact wall 28 and / or the said first thermal interface element 18 are fixed in a watertight manner to the said frame 26, in particular at a shoulder 32 provided inside the said frame 16, here in the vicinity of a longitudinal edge.

[0051] The first housing 20, for example, has a cylindrical configuration. In the illustrated embodiment, the armature 16 is tubular and has opposing longitudinal ends. The contact wall 28 and / or the body 23 of the first thermal interface element 18 have a disc shape, closing the armature 16 at each of the longitudinal ends.

[0052] Advantageously, the contact wall 28 is designed to be in a heat exchange relationship with the cold source. For this purpose, the contact wall 28 comprises a closing portion 34 for the housing 30 and a portion forming a diffusion plate 36, intended to be facing the cold source. The diffusion plate 36 has a larger surface area compared to the closing portion 34.

[0053] Preferably, the dissipation device further comprises a thermal conduction pad 38. This pad is located between the contact wall 28 and the cold source. It improves heat exchange by absorbing any surface defects. This pad also contributes to the electrical insulation spacer between the first thermal interface element 18 and the cold source. It may be fragile, and the presence of the first housing 20 helps to ensure the expected spacer effect. Alternatively, it may consist of a layer of thermally conductive paste.

[0054] Said contact wall 28 and / or said first thermal interface element 18 are, for example, made of copper, copper alloy, aluminum and / or aluminum alloy. Said reinforcement 26 is, for example, made of plastic material, in particular polymer material, more particularly ABS.

[0055] Referring again to Figure 2, we see that, in the illustrated embodiment, the first thermal interface element 18, referred to as the cold element, is configured for heat exchange between the heat pipe 22 and the cold source 16 via the first housing 20. The contact wall 28 is thus in a heat exchange relationship with the cold source 16. The device includes a second thermal interface element 40 for heat exchange between the heat pipe 22 and the other of the hot or cold sources, namely the hot source 12. In other words, the second thermal interface element 40, referred to as the hot element, is configured for heat exchange between the heat pipe 22 and the hot source 12.

[0056] The second thermal interface element 40 includes, for example, a body 42 for fixing to the hot source 12. The second thermal interface element 22 further includes a second sleeve 44 housing the heat pipe 22. The second sleeve 44 is extended from the body 42 of the second thermal interface element 40.

[0057] The heat pipe 22 is fixed in the first or second sleeve(s) 24, 44, for example, by welding, brazing, crimping and / or by press fitting, in particular according to a fit known under the reference H7p6. It is here fixed in the first or second sleeve(s) 24, 44 in the vicinity of opposite longitudinal ends of the heat pipe 22, respectively provided to be inserted into the first and / or second sleeve(s) 24, 44.

[0058] The body 42 of said hot thermal interface member 40 includes, for example, a flange 46 for fixing to said hot source 12. Here, said flange 46 axially extends said second sleeve 44, with or without radial offset.

[0059] Advantageously, the heat pipe 22 is designed to be oriented substantially horizontally. It has a slight, imperceptible inclination, such that, in operation, a first zone of the heat pipe 22 in heat exchange with the hot thermal interface element 40 is vertically positioned at a slightly lower level than a second zone of the heat pipe 22 in heat exchange with the cold thermal interface element 18. The flange 46 is configured to allow angular orientation of the heat pipe 22 in this direction by means of a pivot connection with the hot source 12.

[0060] The said electrical connection box 1 includes said cold source 16 and said hot source 12 as well as the heat dissipation device described above for heat conduction between said hot and cold sources 12, 16.

[0061] The electrical component 14 includes, for example, an electrical protection device such as, in particular, an electrical relay and / or a fuse. In this case, it is a relay. The relay includes, for example, a coil, not visible, electrically connected to electrical connection terminals 50 of the electrical component 14.

[0062] The said electrical component 14 includes, for example, a second housing 52 having said electrical connection terminals 50. More precisely, here, said connection terminals 50 open onto the surface of said second housing 52. Said coil is housed in said second housing 52.

[0063] The said connection terminals 50 include, for example, sockets, passing through said second housing 52. The said electrical connection terminals 50, in particular said sockets, are flush with said second protective housing 52. The said sockets are located, for example, at the level of a face 54 of said second housing 52.

[0064] The second housing 52 is, in particular, substantially parallelepiped in shape. It is fixed, for example, to the cold source 16 of the connection box 1, notably by means of fixing tabs.

[0065] In the illustrated embodiment, said connection box 1 further includes one or more 60 electrical conduction omnibus bars.

[0066] The said bus bars 60 are respectively connected to the said electrical connection terminals 50. The said bus bars 60 are here sandwiched between the said second housing 52, more particularly its face 54 equipped with the said sockets, and the said second thermal interface element 40. In other words, the said bus bars 60 form a thermal bridge between the connection terminals 50 and the said second thermal interface element 40.

[0067] The connection housing 1 includes screws 62 for fixing the bus bars 60, and / or the second thermal interface element 40. The bus bars 60 and / or the second thermal interface element 40, in particular the flange 46, have a first, non-visible opening for the passage of the screw 62. The screw 62 is oriented substantially perpendicular to the face 54 of the second housing 52. The screw 44 passes through the first openings to engage with the socket of the electrical connection terminals 50.

[0068] The body 42 of the second thermal interface element 40, in particular the flange 46, is designed to extend in a plane substantially parallel to the face 54 of the second housing 52. The screw 64 has a head that bears against the flange 56 and / or the bus bars 60. The bus bars 60 also have second ports 64 for electrical connection to other electrical components, not shown, of the connection housing 1 and / or to the rest of the circuit 3. One of the bus bars 60 is bent, while the other is straight. The first and second ports are located at opposite longitudinal ends of the bus bars 60.

[0069] The said cold source 16 includes, for example, a plate 70 having a thermal inertia much greater than the thermal inertia of the heat source formed by the electrical component 14. Advantageously, said plate 70 includes all or part of a lower face of a housing of the electrical energy storage device 2. Said plate 70 advantageously has one or more channels for the circulation of a heat transfer fluid.

[0070] To improve its cooling, said electrical component 14 is here in thermal exchange contact with said plate 70, in particular through one of the faces of said second housing 52.

[0071] It should be noted that, according to another aspect of the invention, the hot and cold sources are reversed so that the first housing is then configured to establish heat exchange between the first thermal interface element and the hot source. In particular, according to this aspect, the contact wall of the housing described above is in contact with the hot source.

Claims

1. DEMANDS 1. Heat dissipation device, particularly for motor vehicles, said device being configured for heat exchange between, on the one hand, a hot source (12) comprising an electrical component (14), and, on the other hand, a cold source (16), said device comprising a first thermal interface component (18), intended to be at an electrical potential substantially identical to an electrical potential of said electrical component (14), said first thermal interface component (18) being configured for heat conduction from the hot source (12) towards the cold source (16), said device further comprising a first housing (20) containing a dielectric fluid, said first housing being configured to establish heat exchange between said first thermal interface component (18) and said cold source (16).

2. Device according to the preceding claim in which said first thermal interface member (18) is configured to be in contact with said dielectric fluid.

3. Device according to any one of the preceding claims in which said first housing (20) comprises an electrically insulating armature (26) and a contact wall (28), said contact wall (28) being thermally conductive and disposed opposite said first thermal interface element (18) with respect to said armature (26) so that said contact wall (28) and said first thermal interface element (18) are electrically insulated from each other, said armature (26), said contact wall (28) and said first thermal interface element (18) together defining a housing (30), said contact wall (28) being intended to be in thermal exchange relationship with said cold source (16).

4. Device according to the preceding claim in which said contact wall (28) comprises a closing part (34) of said housing and a part forming a diffusion plate (36), intended to be opposite said cold source (16), said diffusion plate (36) having an extended surface in relation to said closing part (34).

5. Device according to any one of the preceding claims further comprising a heat pipe (22) for said heat exchange between the hot source (12) and the cold source (16), said first thermal interface member (18) having a first heat exchange surface (18a) in contact with said heat pipe (22).

6. Device according to the preceding claim in which said first thermal interface element (16), said cold, is configured for heat exchange between said heat pipe (22) and said cold source (16) via said first housing (20).

7. Device according to the preceding claim in which said device comprises a second thermal interface element (40), said hot, for heat exchange between said heat pipe (22) and said hot source (12).

8. Electrical connection box for electrical energy storage device, in particular accumulator battery, comprising a cold source (16) and a hot source (12) equipped with an electrical element (14), said connection box further comprising a heat dissipation device (10) according to any one of the preceding claims for heat conduction between said hot and cold sources (12, 16).

9. Electrical energy storage device, in particular accumulator battery, comprising a heat dissipation device according to any one of claims 1 to 7.

10. Vehicle comprising a heat dissipation device according to any one of claims 1 to 7.

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