Electrical connection device, in particular for a motor vehicle, electrical energy storage system, and vehicle comprising such a connection device

Abstract

The invention relates to an electrical connection device, in particular for a motor vehicle, the device comprising one or more heat sources (10) and a cold source (12), the one or more heat sources (10) comprising an electrical member (14), the device comprising a heat pipe (30), a first thermal interface member (32) for exchanging heat between the heat pipe (30) and the cold source (12) and one or more second thermal interface members (34) for exchanging heat between the heat pipe (30) and the one or more heat sources (10), the heat pipe (30) having a first heat exchange surface with the first thermal interface member (32) and one or more second heat exchange surfaces with the one or more second thermal interface members (34), the heat surfaces being configured such that the heat pipe (30) operates as a heat spreader.

Description

[0001] Electrical connection device, in particular for motor vehicles, electrical energy storage systems and vehicles including such a connection device.

[0002] The invention relates to an electrical connection device, particularly for motor vehicles. It also relates to an electrical energy storage system, particularly a battery, comprising such a connection device. Furthermore, it relates to a vehicle comprising such a storage system and / or such a connection 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 are then at increased risk of damage.

[0006] To mitigate this risk, it is common practice to oversize these components. However, this results in significant bulk, an excessive increase in weight, and additional costs.The invention aims to overcome at least in part the previous drawbacks and proposes for this purpose an electrical connection device, in particular for motor vehicles, said device comprising one or more hot sources and a cold source, said hot source(s) comprising an electrical component, said device comprising a heat pipe, a first thermal interface component for heat exchange between said heat pipe and said cold source and one or more second thermal interface components for heat exchange between the heat pipe and said hot source(s), said heat pipe having a first heat exchange surface with said first thermal interface component and one or more second heat exchange surfaces with the second thermal interface component(s), said heat surfaces being configured so that said heat pipe functions as a thermal spreader.

[0007] The term "heat pipe" refers to a heat-conducting component that allows a fluid to circulate within it, primarily by capillary action and / or gravity, in a closed loop based on the principle of successive evaporation and condensation of the fluid. The term "functions as a thermal spreader" refers to a system where the fluid, rather than condensing and evaporating at two opposite ends of the heat pipe while circulating without heat exchange between said ends, exchanges heat with the surroundings, particularly with the cold source, along the entire length of the heat pipe or at least along a functional section of said heat pipe.

[0008] Thus, according to the invention, heat exchange is enhanced by the use of a heat pipe. In the context of an application to an electrical energy storage device, this makes it possible to reduce the temperature to which the safety components will be subjected and to avoid oversizing them. Furthermore, the operation of the heat pipe as a thermal spreader, especially with the use of dedicated exchange surfaces, further improves heat exchange while minimizing its size.

[0009] According to various additional features of the invention, which may be taken together, in any technically compatible combination, or separately, and which constitute so many embodiments of the invention:

[0010] - said heat pipe is straight,

[0011] - said heat pipe has a rounded cross-section, - said heat pipe has a substantially circular cross-section,

[0012] - said heat pipe is sintered,

[0013] - said heat pipe is grooved,

[0014] - said heat pipe has longitudinal ends, in particular tapered, - said first surface extends longitudinally from one of said longitudinal ends to the other,

[0015] - said first surface extends angularly over less than 180° of the cross-section of the heat pipe, along at least part, or even all, of said heat pipe,

[0016] - said second surface extends longitudinally near parts of the longitudinal end of the heat pipe,

[0017] - Alternatively, said second surface extends longitudinally along a median portion of said heat pipe,

[0018] - said second surface extends angularly over less than 180° of the heat pipe cross-section,

[0019] - said first surface extends angularly over 180° of said section along a localized part of said heat pipe,

[0020] - said localized part is situated substantially in said median part, - said first thermal interface element has a first cradle shape with respect to said first exchange surface,

[0021] - said first thermal interface element is formed of a first flange incorporating said first cradle shape,

[0022] - said first flange has protruding edges of said first cradle shape at the level of said median part of the heat pipe,

[0023] - said second thermal interface element has a second cradle shape in relation to said second exchange surface,

[0024] - said second thermal interface element comprises a second flange incorporating said second cradle shape,

[0025] - said second thermal interface element comprises a thermal conduction bar enabling heat exchange between the hot source(s) or at least some of said hot sources and said second flange, - said device comprises a layer of thermally conductive and electrically insulating material enabling electrical isolation between said hot source(s) on the one hand, and said cold source on the other,

[0026] - said layer of thermally conductive and electrically insulating material is located between said first thermal interface element and said cold source,

[0027] - said layer of thermally conductive and electrically insulating material is located between said thermal conduction bar and said second flange,

[0028] - the said hot spring(s) include electrical connection terminals, in particular connected to said electrical component,

[0029] - two of said second flanges thermally connect two of said hot sources respectively to the same heat pipe,

[0030] - said two hot sources are configured to be electrically connected through said same heat pipe by some of the electrical connection terminals, provided at the same electrical potential, of said two hot sources,

[0031] - Alternatively, two of said hot sources are thermally connected to the same of said thermal conduction bars,

[0032] - said two hot sources are configured to be electrically connected through said same thermal conduction bar by some of the electrical connection terminals, provided at the same electrical potential, of said two hot sources,

[0033] - said same thermal, or even electrical, conduction bar is oriented substantially perpendicular to said first flange,

[0034] - Alternatively, the same thermal, or even electrical, conduction bar is oriented substantially parallel to the first flange,

[0035] - The electrical component includes an electrical protection device; - the electrical protection device includes an electrical relay; - the device includes an electrical busbar for electrical connection to said or one of said hot sources, in particular to said electrical component, and more particularly to another of said connection terminals of said hot source(s); - said cold source includes a plate having a thermal inertia much greater than that of said hot source(s). The invention also relates to an electrical energy storage system, in particular a battery, comprising a connection device as described above, in particular in the form of a connection box.

[0036] Advantageously, the cold source plate of the connection device includes all or part of a lower face of a housing of the electrical energy storage system.

[0037] The invention further relates to a vehicle comprising a storage system and / or a connection device as described above.

[0038] The invention will be better understood, and other objects, details, features and advantages thereof will become more apparent from the following detailed explanatory description 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:

[0039] [Fig 1] schematically illustrates, in side view, a motor vehicle according to the invention;

[0040] [Fig 2] schematically illustrates in longitudinal section a principle of operation of a heat pipe used in a conventional way and of a heat pipe used as a thermal spreader;

[0041] [Fig 3] schematically illustrates, in top view, a first example of the device according to the invention;

[0042] [Fig 4] schematically illustrates, in side view, the device of figure 3;

[0043] [Fig 5] schematically illustrates, in top view, a second example of the device according to the invention;

[0044] [Fig 6] schematically illustrates, in side view, the device of figure 5;

[0045] [Fig 7] schematically illustrates in side view a third example of the device according to the invention;

[0046] [Fig 8] schematically illustrates in side view a fourth example of the device according to the invention;

[0047] [Fig 9] schematically illustrates in top view a fifth example of the device according to the invention; [Fig 10] schematically illustrates in top view a sixth example of the device according to the invention;

[0048] [Fig 11] schematically illustrates in perspective the arrangement of figures 3 and 4;

[0049] [Fig 12] reproduces figure 11 in partially exploded mode;

[0050] [Fig 13] illustrates schematically in perspective, in exploded view, some of the non-exploded organs of figure 12;

[0051] [Fig 14] reproduces, enlarged, a central part of figure 4;

[0052] [Fig 15] schematically illustrates in perspective part of the device of figures 5 and 6;

[0053] [Fig 16] schematically illustrates in perspective part of the device in figure 9;

[0054] [Fig 17] schematically illustrates in perspective part of the device in figure 10.

[0055] 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.

[0056] As illustrated in Figure 1, the invention relates to an electrical connection device 1, in particular a connection box, an electrical energy storage system 2, in particular a battery, and a vehicle V comprising such a connection device 1. Said electrical connection device 1, in particular said box, is used for connecting the electrical energy storage system 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.

[0057] As illustrated in particular in figures 3 to 10, said device comprises one or more hot sources 10 and a cold source 12.

[0058] The hot source(s) 10 each include, optionally, an electrical component 14. This electrical component 14 is formed here by an electrical protection device, for example, an electrical relay or a fuse, designed to open in the event of a fault in the circuit 3. It includes, in particular, a coil, which is not visible. The hot source 10 includes, for example, a protective housing 16 forming an enclosure for the electrical component 14, in particular for the coil.

[0059] As more clearly seen in figures 11 to 14, said hot source 10 includes electrical connection terminals 18a, 18b. They are electrically connected to said electrical component 14, in particular to said coil.

[0060] The connection terminals 18a, 18b include, for example, concealed sockets that pass through a wall of the protective housing 16. They further include fixing screws 20 intended to engage with the sockets. The connection terminals 18a, 18b are located, for example, on the same face of the protective housing 16.

[0061] In the illustrated embodiment, three hot sources are observed. For two of them, the electrical component 14 is formed by relays 15, and for the third, the electrical component is formed by a fuse 15'. The hot sources corresponding to the relays 15 have the configuration described above.

[0062] The same applies to the fuse(s) 15 except that the latter include here connection tabs 22 cooperating with a screw / nut system 23, said connection tabs 22 being located at opposite faces of the protection housing corresponding to said fuse(s).

[0063] The cold source 12 comprises, for example, a plate 24 having a thermal inertia much greater than that of the hot source(s) 10. The plate 24 may include all or part of a lower face of a housing for the electrical energy storage system. The plate 24 is provided with one or more channels for circulating a heat transfer fluid.

[0064] According to the invention, the device further comprises a heat pipe 30. A "heat pipe" is defined as a heat-conducting element that allows a fluid to circulate within the element, particularly by capillary action and / or gravity, in a closed cycle based on a principle of successive evaporation and condensation of the fluid. The device according to the invention thus improves heat exchange between the hot source(s) 10 and the cold source 12.

[0065] The said device further includes a first thermal interface element 32 for heat exchange between said heat pipe 30 and said cold source 12 and one or more second thermal interface elements 34 for heat exchange between the heat pipe 30 and said hot source(s) 10. For this purpose, said heat pipe 30 has a first heat exchange surface 32' with said first thermal interface element 32 and one or more second heat exchange surfaces 34' with the second thermal interface element(s) 34.

[0066] The first and / or second thermal interface elements 32, 34 are, for example, made of copper.

[0067] Here, the second thermal interface organ(s) 34 are connected to those of the hot sources 10 comprising relays 15. The fuse 15' is not cooled or at least not directly.

[0068] According to the invention, said heat surfaces 32', 34' are configured so that said heat pipe 30 functions as a thermal spreader.

[0069] This mode of operation will be better understood by referring to Figure 2. In the upper part of the figure, a conventionally operating heat pipe is shown in longitudinal section. It is in contact at each of its longitudinal ends with a hot source, on the left, and a cold source, on the right. The fluid circulating in the heat pipe condenses on the right, transferring heat to the cold source in a first section (I), and evaporates on the left, absorbing heat from the hot source in a second section (II). This allows for particularly efficient cooling of the hot source. Along the heat pipe, the fluid circulates in a central section (III) from the first section (I) to the second section (II) and vice versa, adiabatically, that is, without heat exchange with the external environment. The fluid in its liquid phase flows from right to left across the surface of the heat pipe.The fluid in vapor phase flows in the opposite direction in the core of the heat pipe, the liquid / vapor proportion evolving along the heat pipe.

[0070] In the lower part of the figure, the heat pipe 30 operates according to the invention, that is, as a thermal spreader. It is shown in longitudinal section. In this configuration, the fluid exchanges heat with the external environment along the entire length of the heat pipe 30, or at least along a functional portion of said heat pipe 30. Any adiabatic circulation of the fluid, if it occurs, takes place radially and not longitudinally. Such operation as a thermal spreader, especially with the use of dedicated exchange surfaces, further improves heat exchange while minimizing the overall size.

[0071] In the illustrated embodiment, while contact with the hot source 10 is localized, as in a conventional heat pipe, contact with the cold source 12 occurs along the entire length of the heat pipe 30. The vapor-phase fluid, while expanding longitudinally from an evaporation zone corresponding to the location of the hot source 10, flows essentially radially between opposite longitudinal edges 30a, 30b of the heat pipe 30, at its core. The liquid-phase fluid flows essentially longitudinally at the surface. With the hot source 10 located in a central zone of the heat pipe 30, a portion of this liquid fraction of the fluid flows clockwise through one longitudinal end 30c of the heat pipe 30, and another portion flows counterclockwise through an opposite longitudinal end 30d.

[0072] Preferably, said heat pipe 30 is straight. It has, for example, a rounded cross-section, in particular circular. Said heat pipe 30 is, in particular, sintered and / or grooved.

[0073] Referring to Figures 11 and following, it can be seen that the longitudinal ends 30c, 30d of the heat pipe 30 are, in particular, tapered, for example conical. In other words, here, the first surface 32' extends longitudinally from one base of the tapered longitudinal ends to the other. The second surface 34', on the other hand, extends longitudinally in a localized manner, as will be explained later.

[0074] As can be more clearly seen in Figures 14, 16 and 17, said first surface 32' extends angularly over less than 180° of said cross-section of the heat pipe 30, along at least a portion of said heat pipe 30. In the embodiment of Figure 14, such an angular extension is verified along the entire length of said heat pipe 30. In the embodiment of Figures 16 and 17, said first surface 34' extends angularly over 180° of said cross-section, along a localized portion 36 of said heat pipe 30, namely here a portion, referred to as the median portion, located substantially in the middle of said heat pipe 30.

[0075] In the illustrated embodiments, said second surface 34' extends angularly over less than 180° of said cross-section of said heat pipe 30. According to the embodiment of Figure 14, said second surface 34' extends longitudinally along said mid-section 36 of said heat pipe 30. According to the embodiment of Figures 16 and 17, said second surface 34' extends longitudinally near longitudinal end portions of the heat pipe 30.

[0076] As more clearly seen in figures 12, 16 and 17, said first thermal interface element 32 has a first cradle shape 40 opposite said first exchange surface 32'. Said first thermal interface element 32 is formed, for example, of a first flange 42 incorporating said first cradle shape 40.

[0077] In the embodiment of Figure 12, the first cradle shape 40 has substantially straight free longitudinal edges. In the embodiment of Figures 16 and 17, the first flange 42 has edges 44 projecting from the first cradle shape 40 at the level of the mid-section 36 of the heat pipe 30. These projecting edges 44 correspond to the portion of the first surface 32' whose angular span is 180°.

[0078] The first flange 42 has a heat exchange surface 46 located opposite the cold source 12, in particular the plate 24, and in particular a heat exchange face 47 of the plate 24. The heat exchange surface 46 and / or the heat exchange face 47 are advantageously complementary in shape. They are planar.

[0079] Said first flange 32 flares out from said first cradle shape 40 towards said exchange surface 46 in order to enlarge a heat exchange surface with said cold source 12.

[0080] Said second thermal interface element 34 has a second cradle shape 48 opposite said second exchange surface 34'. Said second cradle shape 48 has substantially straight free longitudinal edges.

[0081] Said second thermal interface element 34 includes a second flange 50 incorporating said second cradle shape 48.

[0082] In the embodiments of figures 12 and 15, said second thermal interface element 34 further comprises a thermal conduction bar 52 enabling heat exchange between said hot source(s) 10 in question and said second flange 50.

[0083] In Figure 12, said bar 52 is substantially straight. Said hot springs 10 are located at opposite longitudinal ends of said bar 52. Said second flange 50 is located along said bar 52 at a distance from said hot spring(s) 10, in particular in the middle of said bar 52.

[0084] In Figure 15, the bar 52 is T-shaped. The hot springs 10 are located at opposite ends of one long bar of the T. The second flange 50 is located at one free end of one short bar of the T. According to the embodiment shown in Figures 16 and 17, the second flange(s) 50 are fixed to the hot spring(s) 10. They have a fixing portion 55 provided with a passage 56 for one of the screws 20. The second flange 50 extends parallel to the heat pipe 30 in the embodiment shown in Figure 16. The second flange 50 extends perpendicularly to the heat pipe 30 in the embodiment shown in Figure 17.

[0085] Preferably, the second thermal interface element(s) 34 are fixed, for example, to certain 18a of the electrical connection terminals. The hot source(s) 10 are thus cooled via their electrical circuit.

[0086] All or part of the second thermal interface element(s) 34 are thus energized. The same may also apply to the heat pipe 30 and / or the first thermal interface element 32, as will be explained later. Such thermal and electrical contact between the hot source(s) 10 and the second thermal interface element(s) 34 occurs, in particular, through contact between the bushings and / or screws 20, on the one hand, and the conduction bars 52 or the second flanges 50, as applicable.

[0087] In this context, to electrically isolate said cold source 12 from said hot source(s) 10, said device includes a layer 54 of thermally conductive and electrically insulating material between said hot source(s) 10 and said cold source 12. Said layer 54 of thermally conductive and electrically insulating material takes, for example, the form of a pad, possibly compressible.

[0088] In the embodiment of Figures 11 to 14 and 15, said layer 54 of thermally conductive and electrically insulating material is located between said thermal conduction bar 52 and said second flange 50. Direct contact can then take place between said first thermal interface element 32 and said cold source 12. Said first thermal interface element 32 is thus possibly made of material from said cold source 12.

[0089] In the embodiment of Figures 16 and 17, and as is more clearly seen in Figures 9 and 10, said layer 54 of thermally conductive and electrically insulating material is located between said first thermal interface element 32 and said cold source 12. More precisely, here it is located between said exchange surface 46 and said exchange face 48.

[0090] From these figures, it can be seen that two of the said second flanges 50 thermally connect two of the said hot sources 10 to the same heat pipe 30. In such a configuration, the said two hot sources 10 are electrically connected to each other by certain 18a of their electrical connection terminals, provided at the same electrical potential, through the said same heat pipe 30.

[0091] In other words, the said connection terminals 18a in question serve both for heat conduction from the hot sources 10 to the cold source 12, through said heat pipe 30, and for current conduction between the hot sources 10, also through the heat pipe 30.

[0092] Referring again to the embodiments of figures 3 to 8, we find that, as an alternative but with the same result, two of said hot sources 10 are thermally connected to the same of said thermal conduction bars 52. The two hot sources 10 are electrically connected to each other by certain 18a of their electrical connection terminals, provided at the same electrical potential, through said same thermal conduction bar 52.

[0093] In figures 3 and 4, said thermal, or even electrical, conduction bar 52 is oriented substantially perpendicular to said first flange 42. In figures 5 to 8, said thermal, or even electrical, conduction bar 52 is oriented substantially parallel to said first flange 42.

[0094] In figures 5 and 6, the said cold source 12 is located below the said hot source(s) 10. It is substantially horizontal in use.

[0095] In Figure 7, the cold source 16 is substantially vertical in use. The thermal, or even electrical, conduction bar 52 is T-shaped, as mentioned above in relation to Figures 5 and 6, as well as 15. Its shorter arm is also bent to face the cold source 12.

[0096] In Figure 8, the cold source 12 is located above the hot source(s) 10. It is substantially horizontal in use. The thermal, or even electrical, conduction bar 52 is T-shaped, as mentioned above.

[0097] As illustrated in Figure 11, said device further comprises, for example, one or more electrically conductive busbars 100. These are intended to be electrically connected to said hot source(s) 10, in particular to said electrical component 14, and more particularly to the other 18b of said connection terminals of said hot source(s) 10.

[0098] The aforementioned busbar(s) 100 electrically connect the relay(s) 15 and the fuse(s) 15'. They can also connect the aforementioned relay(s) 15 and / or the aforementioned fuse(s) 15' to circuit 3.

Claims

DEMANDS 1. Electrical connection device, in particular for motor vehicle, said device comprising one or more hot sources (10) and a cold source (12), said hot source(s) (10) comprising an electrical component (14), said device comprising a heat pipe (30), a first thermal interface component (32) for heat exchange between said heat pipe (30) and said cold source (12) and one or more second thermal interface components (34) for heat exchange between the heat pipe (30) and said hot source(s) (10), said heat pipe (30) having a first heat exchange surface (32') with said first thermal interface component (32) and one or more second heat exchange surfaces (34') with the second thermal interface component(s) (34), said heat surfaces being configured so that said heat pipe (30) functions as a thermal spreader.

2. Device according to claim 1 in which said heat pipe (30) has a rounded straight section, in particular circular.

3. Device according to any one of the preceding claims in which said first thermal interface member (34) has a first cradle shape (40) with respect to said first exchange surface (32).

4. Device according to the preceding claim in which said first thermal interface member (32) is formed of a first flange (42) incorporating said first cradle shape (40).

5. Device according to the preceding claim in which said first flange (42) has edges (44) projecting from said first cradle shape (40) at the level of a median part of the heat pipe (30).

6. A device according to any one of the preceding claims, wherein said second thermal interface element (34) has a second cradle shape (48) opposite said second exchange surface (34').

7. A device according to the preceding claim, wherein said second thermal interface element (34) comprises a second flange (50) incorporating said second cradle shape (48).

8. Device according to the preceding claim in which said second thermal interface member (34) comprises a thermal conduction bar (52) enabling heat exchange between said hot source(s) (10) and said second flange (50).

9. Device according to any one of the preceding claims in which said device comprises a layer (54) of thermally conductive and electrically insulating material for electrically isolating said hot source(s) (10) from each other, on the one hand, and said cold source (12) on the other hand.

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

11. Vehicle comprising a device according to any one of claims 1 to 9.

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