Cooling device

Abstract

The invention relates to a cooling device (30) for at least one element to be cooled, for example at least one electric battery element, comprising: - at least one flexible wall (36), - at least one flow channel (52) for heat-transfer fluid delimited at least partially by the wall (36), the wall (36) being configured to be placed in contact with the at least one element to be cooled, between the channel (52) and the at least one element to be cooled, and - a support structure (34) comprising a rigid frame (35) and / or a rigid intermediate structure (82) secured to the wall (36) and extending into the channel (52), - at least one active temperature-control element (60), and - optionally, at least one sensor (70), each active temperature-control element (60) and, as the case may be, each sensor (70) being mounted on the frame (35) or the intermediate structure (82).

Description

[0001] DESCRIPTION

[0002] TITLE: Cooling Device

[0003] Technical field of the invention

[0004] The invention relates to a cooling device for at least one element to be cooled, for example at least one electric battery element.

[0005] The invention also relates to an electric battery comprising such a cooling device.

[0006] Prior art

[0007] In a multi-cell battery, that is, a battery comprising several independent battery cells grouped within a casing, the hottest cells are located in the center. Since the cells are generally arranged side-to-side to reduce overall size, the heat generated by these most enclosed cells is dissipated only through their undersides. The electrical connectors between these different battery cells are usually located on the top surfaces and are also likely to generate significant heat.

[0008] Indirect fluid cooling is the most common method used by manufacturers because it is efficient, relatively simple to implement, and inexpensive. This method involves circulating a heat transfer fluid, or cooling fluid (usually a water-glycol mixture), through a cooling system located beneath the battery cells. The fluid acts as a heat transfer fluid, removing thermal heat from the battery and dissipating it outside the enclosure as it circulates. Consequently, heat dissipation is highly dependent on the thermal resistance between the electrical connectors or the underside of the battery cells (depending on the application) and the cooling system.

[0009] To improve this thermal exchange resistance, it is known to use thermal interface materials, such as thermally conductive resins, between the cold plate of the cooling device and the undersides of the battery cells or the complex structures of the connectors. This bridges the local gaps between these surfaces caused by the asperities and roughness of these solid structures. However, such a solution significantly increases the cost and mass of the battery. Furthermore, the thermal contact achieved through the use of such an interface material remains considerably less efficient than direct mechanical contact between conductive metallic materials.Another possibility for improving thermal contact is the use of a flexible, deformable wall, particularly in a flexible envelope for the circulation of the heat transfer fluid instead of a rigid structure. The flexible wall deforms freely under the effect of the circulation pressure of the heat transfer fluid and then conforms to the contours of the underside of the battery elements or electrical connectors, thus providing good thermal contact.

[0010] For example, a flexible envelope of this type is designed using two sheets of multi-material, multi-layered film joined by local welding to form one or more fluid circulation channels. The two sheets can be separate or formed from a single sheet folded over itself.

[0011] Such a flexible casing thus allows for a cooling device that benefits from good thermal contact with the battery elements to be cooled, while being lightweight and simple to manufacture compared to previous rigid coolers.

[0012] The implementation of such a flexible envelope for cooling battery elements is described for example in patent applications FR2311874 and FR2311875 or FR2405865.

[0013] There are other types of cooling devices that include a flexible wall forming the thermal interface between the heat transfer fluid and the elements to be cooled, which are not necessarily limited to battery elements.

[0014] However, such a cooling system, which includes a flexible wall delimiting the heat transfer fluid circulation duct, can still be improved. Indeed, controlling the efficiency of fluid circulation cooling is difficult, primarily due to the lack of feedback on the internal conditions of the casing and the limited ability to correct any inefficiencies in the cooling process. For example, a fluid temperature that is too low can, counterintuitively, cause cooling problems by significantly increasing the fluid's viscosity, or even triggering a freeze-thaw phase change, which hinders proper circulation in certain areas of the duct and reduces the uniformity of the cooling.

[0015] Presentation of the invention

[0016] The invention aims to improve control over the cooling efficiency and homogeneity of the heat transfer fluid circulation within the duct. Thus, the invention proposes a cooling device for an electric battery, employing a flexible interface wall as described above and enabling active temperature control, and therefore, in particular, control of the viscosity of the fluid circulating in the duct. To this end, the invention relates to a cooling device for at least one element to be cooled, for example, at least one electric battery cell, the cooling device comprising:

[0017] - at least one flexible wall,

[0018] - at least one heat transfer fluid circulation duct delimited at least in part by said at least one wall, said at least one wall being configured to be in contact with the at least one element to be cooled, between said duct and the at least one element to be cooled, and

[0019] - a support structure for at least one wall, comprising a rigid frame enclosing the edges of at least one wall and / or a rigid intermediate structure attached to at least one wall and extending into the duct,

[0020] characterized in that the cooling device further comprises:

[0021] - at least one active thermoregulation element configured to deliver controlled thermal power to at least one fluid contained in at least one duct, and / or at least one sensor,

[0022] each active thermoregulation element and each sensor being mounted on the frame or intermediate structure.

[0023] Such a cooling system allows for local adjustment of the fluid temperature, raising or lowering it, to improve fluid circulation within the casing and ensure more even cooling. Temperature control is thus achieved as close as possible to the fluid cooling the battery cells, thereby improving its efficiency.

[0024] The cooling device may include at least one fluid inlet connector and at least one fluid outlet connector of the casing, opening into at least one fluid circulation duct.

[0025] The cooling device may include a plurality of sensors and / or a plurality of active thermoregulation elements distributed along at least one duct.

[0026] Such a feature makes it possible to adapt the temperature regulation to local conditions at every point along the duct, providing more heat to areas that are too cold without providing it to areas that do not need it.

[0027] At least one active thermoregulation element may include at least one electrical resistance or at least one Peltier effect cell.

[0028] Such a characteristic makes it possible to realize the active thermoregulation element in a simple and robust manner, and, in the case of Peltier cells, to provide negative thermal power.

[0029] At least one active thermoregulation element may include at least one heating wire integrated into the frame or mounted on the intermediate structure and extending preferably along an external contour of at least one wall or along the duct. Such a feature makes it possible to deliver homogeneous thermal power to the fluid at the lateral edges of the casing or over the entire length of the duct.

[0030] The sensor must include at least one of the following: a temperature sensor, a hydrostatic pressure sensor, a viscosity sensor, and a humidity sensor. This feature allows for the detection of excessively high or low fluid temperatures, excessive pressure or viscosity in the flow, or abnormal conditions within the enclosure, such as overheating, leaks, or excessive condensation.

[0031] The frame may define at least one housing, said housing being configured to receive at least partially one of at least one sensor and / or one of at least one active temperature control element. The frame also defines an access channel extending through the frame from the housing to at least one conduit, so as to allow contact between the fluid and the sensor or active temperature control element housed in the housing. This feature allows a sensor or temperature control element to be mounted on the frame in a removable and protected manner while ensuring access to the fluid within the casing.

[0032] The support structure may include the intermediate structure, said intermediate structure comprising a lateral portion and at least one support arm extending from the lateral portion into at least one duct, said support arm carrying at least one active thermoregulation element and / or at least one sensor.

[0033] This feature makes it possible to improve the mechanical resistance of the casing and to place the sensors at the heart of the conduit, in the fluid flow.

[0034] The lateral portion may extend along the lateral edges of at least one wall and form at least one weld region in which at least one wall is fixed to the intermediate structure.

[0035] This feature makes it possible to stiffen the envelope at the edges to stabilize its shape, and fixes the sensors and thermoregulation elements mounted on the intermediate structure.

[0036] The intermediate structure may further include a median portion attached to the lateral portion and forming at least one welded region in which at least one wall is fixed to the intermediate structure.

[0037] This feature allows the sheets to be fixed to the intermediate structure at the central weld regions forming the profile of the conduit and the support arms to be attached to this middle portion.

[0038] The invention also relates to an electric battery comprising: - a plurality of battery cells arranged in an enclosure, each battery cell having cooling elements arranged on an upper, lower, or lateral face of the battery cell, and

[0039] - a cooling device as described above,

[0040] the casing being arranged to come into contact with the elements to be cooled when a cooling fluid circulates in at least one conduit.

[0041] Brief description of the figures

[0042] Figure 1 is a schematic cross-sectional view of an electric battery comprising a cooling device according to the invention.

[0043] Figure 2 is a perspective view of the cooling device in Figure 1.

[0044] Figure 3 is a cross-sectional view of the cooling device of Figure 2. Figure 4 is a detailed cross-sectional view of a sensor mounted in the support structure of the cooling device of Figures 2 and 3.

[0045] Figure 5 is a schematic cross-sectional view of the cooling device according to a second embodiment of the invention.

[0046] Figure 6 is a perspective view of a support structure for the cooling device in Figure 5.

[0047] Detailed description of the invention

[0048] Figure 1 represents an electric battery 10 intended for energy storage, intended in particular for applications on board a vehicle, for example an electric or hybrid powered vehicle.

[0049] The said vehicle is, for example, a motor vehicle, a road or rail transport vehicle, a maritime vehicle, or other.

[0050] Alternatively, battery 10 is intended for a fixed or mobile installation requiring an electrical power supply, without connection to the power grid, or as a supplement to it.

[0051] The battery comprises a closed enclosure 12, substantially sealed, and a plurality of battery elements 14, or cells, arranged in the enclosure 12 and suitable for storing electrical energy.

[0052] The enclosure 12 includes a removable top cover 15 to allow access to the battery elements 14. The enclosure 12 also defines openings 16 in one of the walls, through which are placed pipes 17 for circulating heat transfer fluid, or cooling fluid, which allows the supply of cooling fluid through the walls of the enclosure, from an external reservoir equipped with a circulation pump (not shown).

[0053] Each battery element 14 has a general shape that is substantially parallelepiped-shaped and thus defines an upper face 18, a lower face 20 and four lateral faces.

[0054] The terms "upper" and "lower" are understood here in relation to a standard positioning of the battery under operating conditions.

[0055] The battery elements 14 are arranged aligned in at least one row extending along an alignment direction X. An elevation direction Z and a transverse direction Y are further defined, both perpendicular to each other and perpendicular to the alignment direction X, the elevation direction Z being oriented substantially vertically in a standard operating orientation of the battery 10.

[0056] The battery elements 14 can be arranged in contact with each other by their respective lateral faces, along the alignment direction X, or with small gaps between two neighboring battery elements along the alignment direction X.

[0057] Each battery element 14 has connectors arranged on its upper face 18, on either side of said upper face 18 along the transverse direction Y. The connectors of the battery elements 14 thus form two rows extending along the alignment direction X.

[0058] The connectors of the battery elements 14 are connected to parallel bus bars 24 which extend substantially along the alignment direction X, allowing energy to be supplied to the battery elements 14 for storage or energy to be withdrawn from the battery elements to power an electrical device.

[0059] Battery 10, and more specifically battery elements 14, generate heat during operation and require cooling for optimal operation and to have a satisfactory operating time and safety.

[0060] For this purpose, the battery 10 includes at least one cooling device for 30 battery elements to be cooled.

[0061] The elements to be cooled may be the battery cells 14, and more specifically the lower faces 20 or lateral faces of the battery cells, or the connectors of the battery cells as well as the bus bars 24, which are arranged above the upper faces of the battery cells.

[0062] In the example in Figure 1, the cooling device 30 is arranged to cool the battery element connectors and the bus bars 24, and is positioned in the enclosure 12, suspended from the cover, above the battery elements 14.

[0063] The cooling device 30 includes a casing 32 for receiving the heat transfer fluid which circulates to cool the battery elements 14. Said casing 32 includes at least one flexible wall 36, for example formed of a sheet of flexible film, said wall 36 being arranged to form a contact surface between the casing 32 and the elements to be cooled, so as to take advantage of the easily deformable nature of the wall 36 to improve the thermal contact on this surface.

[0064] In the example shown, the envelope 32 comprises two such walls 36, forming two opposite faces of the envelope 32 and defining between them an internal space of the envelope 32.

[0065] The flexible material forming the wall(s) 36, or film, is, for example, a stack of layers as follows: a first layer of polyethylene terephthalate (PET), a layer of aluminum (Al), a second layer of polyethylene terephthalate, and a layer of polyethylene (PE). This type of film is commonly used in the food industry for product insulation.

[0066] In the case of the flexible envelope 32, the aluminum layer provides very good thermal conductivity and reduces the risks of fluid permeation through the sheets, the polyethylene terephthalate layers provide good resistance to temperature and ambient environment, and the polyethylene layer serves as an adhesive layer, for fixing the two sheets by melting the two polyethylene layers in contact with each other.

[0067] According to an alternative (not shown), the cooling device comprises at least one rigid or semi-rigid part to which at least one flexible wall 36, as described above, is attached. This flexible wall 36 is attached to the rigid or semi-rigid parts by welded regions to form a closed enclosure and is designed to deformably move away from these rigid or semi-rigid parts in separation regions extending between the welded regions.

[0068] In the example shown in the figures, the flexible envelope 32 has a substantially rectangular shape. The rectangular shape of the envelope 32 comprises, for example, two long sides 44, which extend along the alignment direction X, and two short sides 46, which extend along the transverse direction Y.

[0069] The envelope 32 defines lateral edges, in particular external lateral edges extending along the long sides 44 and the short sides 46.

[0070] Alternatively, other shapes of the 32 envelope can be considered for different battery geometries, for example T-shaped, L-shaped, etc...

[0071] The casing 32 defines an inner face 47, which is formed by the wall 36 oriented towards the interior of the enclosure 12 and intended to be in contact with the battery elements 14, and an outer face 48, formed by the wall 36 oriented away from the battery elements 14. Generally, in embodiments other than the casing 32 described above, the inner face 47 is always formed by a flexible sheet 36 to allow close contact with the battery elements. The outer face 48 can be rigid or semi-rigid and formed by the rigid or semi-rigid parts of the casing mentioned above.

[0072] Preferably, the outer face 48 is also flexible and formed of a wall 36 like the inner face 47.

[0073] The cooling device 30 also includes a rigid support structure 34 adapted to support the flexible wall(s) 36 and improve the rigidity and strength of the cooling device 30. Several embodiments of the support structure 34 are described below.

[0074] The cooling device 30 further includes at least one inlet fluid connector 50 and at least one outlet fluid connector 50, both opening into the enclosure 32, and at least one fluid circulation conduit 52 delimited by the wall(s) 36, in the enclosure 32, from the inlet conductor to the outlet conductor.

[0075] In the example shown, the inlet and outlet fluidic connectors 50 are positioned on the same side of the rectangular shape of the envelope 32.

[0076] For example, the two fluidic connectors 50 are positioned on the same short side 46 of the rectangular shape of the envelope 32, that is to say at the level of the same end of the envelope 32 along the alignment direction X, and on either side of said rectangular shape along the transverse direction Y.

[0077] The fluidic connectors 50 are arranged in respective inlet or outlet ports provided in the walls 36 forming the envelope 32, so as to put the circulation conduits 52 into fluidic communication with the cooling fluid circulation pipes.

[0078] In the example shown, the enclosure 32 includes a single fluid circulation conduit 52 having a U-shape, i.e. the conduit 52 extends from the inlet connector 50 along one of the long sides 44, then along the short side 46 opposite the connectors 50, and along the other of the long sides 44 to the outlet connector.

[0079] More generally, the conduit 52 extends along a path forming at least one round trip on the envelope 32, in order to run alongside the two rows of connectors of the battery elements 14 and to allow the fluidic connection of the inlet and outlet at the same lateral edge of the envelope 32.

[0080] Thus, conduit 52 can have a V-shape, a W-shape, etc...

[0081] The conduit 52 can also extend along a meandering path over the extent of the envelope 32, i.e. forming at least one bend, for example in an S shape, which allows the cooled surface to be increased.

[0082] Alternatively, the enclosure 32 may comprise several conduits 52 extending divergently from at least one inlet point and converging at at least one outlet point. Alternatively still, the cooling device may comprise a plurality of conduits 52 fluidically separated from each other, provided with their respective fluidic connectors 50.

[0083] In particular, the cooling device 30 may include two substantially straight and parallel conduits 52 extending along the two rows of connectors and bars 24, according to the alignment direction X.

[0084] According to the invention, the cooling device 30 comprises at least one thermal regulation element 60 and / or at least one sensor 70, mounted on said rigid support structure 34.

[0085] Each active thermoregulation element 60 is designed to deliver thermal power, in a controlled manner, to supply heat to its immediate environment or to remove heat from its immediate environment, for example, to raise or lower its temperature. The term "thermal power" is therefore understood algebraically and can represent a negative value (heat removal, or calories) or a positive value (heat addition, or calories).

[0086] Thermal power is delivered in particular at least to the heat transfer fluid which circulates in the duct 52.

[0087] For example, each active thermoregulation element 60 may include at least one electrical resistor, capable of delivering heat by Joule heating when an electrical voltage is applied across its terminals, or at least one Peltier cell, capable of delivering or removing heat by Peltier heating when a voltage is applied between its electrodes. The addition of thermal energy to the heat transfer fluid allows for the correction, preferably locally, of excessively low fluid temperatures that would excessively increase its viscosity and impede proper fluid flow.

[0088] The removal of calories allows the fluid and / or the internal environment of enclosure 12 to be cooled locally, to prevent the formation of hot spots.

[0089] Each 70 sensor is designed to measure at least one quantity of its environment, for example temperature, pressure, humidity, or other.

[0090] For example, each sensor 70 can be arranged to measure the quantity inside the casing, in particular in the cooling fluid, outside the casing 32, in particular at the battery elements 14, or both inside and outside the casing 32. The measurement can be carried out directly in contact with the fluid or through the wall 36.

[0091] The sensor 70 can, for example, be a temperature sensor, allowing the detection of a temperature that is too high, or too low in the case of the cooling fluid, and thus correcting this abnormal temperature, in particular by activating one or more of the active thermoregulation elements 60. Alternatively, at least one of the sensors 70 can be a hydrostatic pressure sensor arranged to measure the pressure of the cooling fluid at a point in the conduit 52.

[0092] The sensor 70 can also be arranged to measure a quantity within the enclosure, for example a humidity sensor intended to detect a leak or a risk of excessive condensation.

[0093] The sensors 70 allow for fine-tuning, preferably locally, the control of the active thermoregulation elements 60 in order to better correct temperature and viscosity deviations of the cooling fluid.

[0094] Each active thermoregulation element 60 and each sensor 70 is connected to a remote control unit, not shown, by means of dedicated connectors, also not shown. A first embodiment is described below, with reference to Figures 2 to 4. In the first embodiment, the cooling device 30 comprises the casing 32 formed of two flexible walls 36 extending opposite each other and partially welded to each other.

[0095] Thus, the envelope 32 has welding regions 38, in which the walls 36 are joined together, and separation regions 40, in which the walls 36 are not welded together and are thus able to extend the gap between them, defining an internal space between them.

[0096] The weld regions 38 follow in particular the external contour of the envelope 32, so as to seal an internal space of the envelope 32.

[0097] The walls 36 are for example formed from the sheets of the film described above, cut to obtain the desired geometry, for example rectangular as shown.

[0098] The term "sheet" is used here in a broad sense, and includes cases where each of the two sheets 36 is composed of several pieces initially separate and fixed together to form a single sheet. These sheets 36 may also be formed from two parts of a single, larger sheet folded over itself along at least one fold line, each sheet then being defined by said fold line and its free edges.

[0099] As shown in Figures 2 and 3, the conduit 52 extends between the walls 36 of the casing, through the separation regions 40, from at least one inlet connector 50 to at least one outlet connector 50. In Figure 3, the flow of the cooling fluid is represented by arrow F.

[0100] In this first embodiment shown in figures 2 to 4, the support structure 34 includes a rigid frame 35 configured to carry and hold the walls 36.

[0101] The frame 35 of the support structure 34 is substantially rectangular and encloses the outer lateral edges of the walls 36. This frame is, for example, made of plastic by molding, stamping, or an additive manufacturing process. The terms "rigid" and "flexible" are understood here in a relative sense. Furthermore, the flexibility of the walls 36, or even, depending on the case, of the entire casing 32, implies that, without external force, these parts deform under their own weight, whereas the rigidity of the support structure 34 implies that it does not undergo significant deformation under its own weight.

[0102] The frame 35 is advantageously fixed to the cover 15 by suitable fastening means. Alternatively, the rigid frame 35 can be fixed to the side faces of the enclosure 12 or to the bottom of the enclosure 12, so as to bring the flexible casing 32 into contact with the side or bottom faces, respectively, of the battery elements 14.

[0103] The fastening means can also or alternatively be adapted to fix the support structure 34 to the battery elements 14, in particular to the lower 20, lateral or upper 18 faces of the battery elements 14.

[0104] The means of fixing the frame 35 are, for example, positioned along the outer edge of the frame.

[0105] The means of fixing the support structure 34 are, for example, snap-fit ​​fixing means, screw fixing means, or articulated means.

[0106] According to an unrepresented variant, the fluidic connectors 50 can be fixed to the frame 35, engaged in corresponding orifices provided in the frame 35, or even be defined directly in the structure of the frame 35.

[0107] In this first embodiment, at least one active thermoregulation element 60 and / or at least one sensor 70 is mounted on the frame 35.

[0108] For example, at least one such active thermoregulation element 60 can, for instance, be a small device relative to the frame 35, comprising at least one heating element or at least one Peltier cell, for example, disposed in direct contact with the cooling fluid or in thermal contact through the film of the casing 32. This allows for a localized supply of thermal power, in order to correct a hot spot or a cold spot in the fluid flow within the conduit 52. Such small devices can be distributed along the conduit 52 in order to supply thermal power to the fluid in different portions of said conduit 52.

[0109] As shown in Figures 3 and 4, the active temperature control element(s) 60 can be fixed to the frame 35 and positioned externally in contact with the casing 32, or they can be fixed to the frame 35 on one side and extend through the peripheral weld regions of the casing 32 to be in contact with the fluid flowing in the conduit 52. Advantageously, such active temperature control elements 60 are configured to operate independently of each other. For this purpose, each active temperature control element 60 is connected to the control unit by independent connectors and is controlled independently by said control unit, for example, by means of connecting cables or dedicated conductive tracks (not shown).

[0110] This allows the thermoregulation effect to be localized at different points along the path of the heat transfer fluid, in order to correct thermal imbalances in the fluid locally, based in particular on information obtained by means of sensors 70.

[0111] Alternatively or in addition to the small-sized active thermoregulation elements 60 described above, the cooling device 30 may also include as an active thermoregulation element 60 at least one heating wire 62 integrated into the frame 35 and extending preferentially along an external contour of the wall 36, visible in Figures 2 and 3.

[0112] At least one heating wire 62 extends in particular to the immediate vicinity or in contact with the wall 36 so as to be thermally in contact with the fluid in the conduit 52. Such an active thermoregulation element 60 of the heating wire type allows an overall supply of thermal power on the periphery of the wall 36.

[0113] Each sensor 70 is also mounted on the frame 35 and positioned to measure a property of the enclosure and / or the fluid. In particular, each sensor 70 mounted on the frame 35 can be positioned in contact with the wall 36 to measure a property of the fluid through said wall, for example, its temperature. Preferably, the sensors 70 are distributed along the fluid circulation conduit 52, for example, alternately with the active temperature control elements 60.

[0114] Alternatively, the sensor 70 can be arranged away from the wall 36, to measure a quantity within the enclosure, as with a humidity sensor.

[0115] Alternatively, as shown in Figure 4, at least one of the active thermoregulation elements 60 or sensors 70 is received in a housing 72 provided in the frame 35. In the example of Figure 4, the sensor 70 received is, for example, a hydraulic pressure sensor.

[0116] The said housing 72 opens in an external wall of the frame 35, in a direction opposite to the conduit 52, the said housing 72 being configured to receive at least in part the sensor 70, as well as a retaining ring 74 arranged around the sensor 70.

[0117] The frame 35 also defines an access channel 76 extending through the frame 35 from the housing 72 into the conduit 52, so as to allow contact between the heat transfer fluid and the sensor 70.

[0118] The fluid column present in the access channel 76 is preferably short enough so that the associated pressure loss is low.

[0119] Figure 4 also shows a retaining pin 78 comprising a connector 80, mounted on the frame 35 and holding the sensor 70 in the housing, and allowing its connection to the control unit. Alternatively, in addition to or instead of such sensors 70, it is possible to measure the temperature of the fluid at the outlet of the enclosure 12, in the pipes 17, the pressure drop following passage through the conduit 52, the variation of the inlet and outlet fluid flow rates, etc., in order to control the activation of the active thermoregulation elements 60.

[0120] According to a second embodiment, shown in figures 5 and 6, the support structure 34 includes an intermediate structure 82 interposed between the walls 36 of the envelope 32 so as to stiffen it.

[0121] The intermediate structure 82 is shown in figures 5 and 6, and takes the form of a perforated plate so as to form a lateral portion 84 forming its external edges, a median portion 86, and support arms 88 extending from the lateral portion 84 and / or the median portion 86, and preferably from the lateral portion 84 to the median portion 86 to connect them.

[0122] The intermediate structure 82, for example, is made of plastic material, notably by molding, stamping or additive manufacturing.

[0123] The openings in the intermediate structure 82 are preferably located at the separation regions 40, in order to allow free circulation of fluid in the internal spaces between the walls 36 defined by the weld regions 38 and the intermediate structure 82 itself. Advantageously, said openings cover at least 50% of the surface of the intermediate structure, and preferably at least 70% of said surface.

[0124] The weld regions 38 are regions in which the walls 36 are fixed on either side of the intermediate structure 82 by welding, on the lateral portion to form the closed lateral edges of the envelope 32 and, preferably, on the middle portion to delimit the conduit 52. Alternatively, the walls 36 can be fixed to the intermediate structure 82 by gluing, by pinching, or other alternative means of fixing, the term weld regions being taken in a broad sense.

[0125] Alternatively, the middle portion may be reduced or absent, and the weld regions may constitute welds between the two walls 36 to form the conduit 52, in addition to the weld regions to the lateral portion to form the edges of the envelope 32.

[0126] The separation regions 40 are regions in which the walls 36 are able to move away from the intermediate structure 82 under the effect of cooling fluid pressure, to form the conduit 52 on either side of the intermediate structure. The intermediate structure 80 also includes at least one track 90 carried by the support arms 88 and arranged to extend along the conduit 52 within the casing 32.

[0127] In the example shown, fixing elements 92 of the intermediate structure 82 are attached to the lateral portion 84, said fixing elements 92 being arranged to allow the intermediate structure 82 to be fixed to the walls of the battery enclosure, either directly or via an optional stiffening frame 94. The stiffening frame 94 is, for example, a rectangular structure surrounding the external edges of the walls 36 to stiffen them and including dedicated holes 96 to allow its attachment to the walls of the enclosure.

[0128] In the example of figures 5 and 6, the fluidic connectors 50 for the inlet and outlet of the fluid are integrated into the intermediate structure 82, at the level of the lateral portion 84. The walls 36 are welded on either side of these connectors 50, to allow access to the internal space of the envelope 32.

[0129] Alternatively, a frame 35 as described above can be arranged around the envelope 32, so as to enclose the edges of the walls 36 and part of the lateral portion 84 of the intermediate structure 82.

[0130] A heating wire 62 is mounted on the intermediate structure 82 and extends along one of the tracks 90, along the conduit 52, from a dedicated connector 96 attached to the lateral portion of the intermediate structure 82. Said heating wire 62 is immersed in the heat transfer fluid and constitutes an active thermoregulation element 60 of the cooling device 30.

[0131] Other active thermoregulation elements 60 and sensors 70 are mounted on the intermediate structure 82, in particular on the support arms 88 and / or on the tracks 90, as shown in Figure 5. These active thermoregulation elements 60 and sensors 70 are immersed in the fluid circulating in the conduit 52.

[0132] The active thermoregulation elements 60 and the sensors 70 are of the type described above in the first embodiment, with identical associated advantages, except that these elements are immersed in the fluid circulating in the conduit 52 and thus benefit from better thermal contact with the fluid for the regulation of temperature, viscosity and pressure of said fluid.

[0133] The active thermoregulation elements 60 and the sensors 70 are, for example, distributed along the conduit 52 and advantageously alternated with each other along the conduit 52, so as to implement localized regulation of the fluid temperature to avoid the formation of hot spots or cold spots in the flow.

[0134] Other embodiments of the cooling device 30 may include flexible walls 36 of different types than the film sheets described above, as long as these walls have good thermal conductivity and are deformable to allow good thermal contact with the elements to be cooled.

[0135] Other geometries can also be considered to replace the flexible envelope 32, including for example rigid or semi-rigid parts on which the flexible wall 36 forming the thermal interface is fixed.

[0136] Finally, the example described falls within the preferred framework of cooling electric battery elements, but the cooling element 30 can find application in many technical fields requiring local cooling, particularly within a closed enclosure, for example in computer systems.

Claims

DEMANDS 1. Cooling device (30) for at least one element to be cooled, for example at least one electric battery cell, the cooling device (30) comprising: - at least one flexible wall (36), - at least one heat transfer fluid circulation conduit (52) delimited at least in part by said at least one wall (36), said at least one wall (36) being configured to be placed in contact with the at least one element to be cooled, between said conduit (52) and the at least one element to be cooled, and - a support structure (34) for at least one wall (36), comprising a rigid frame (35) enclosing the edges of at least one wall (36) and / or a rigid intermediate structure (82) integral with at least one wall (36) and extending into the duct (52), characterized in that the cooling device (30) further comprises: - at least one active thermoregulation element (60) configured to deliver controlled thermal power to at least the fluid contained in at least one duct (52), and - optionally, at least one sensor (70), each active thermoregulation element (60) and, where applicable, each sensor (70) being mounted on the frame (35) or intermediate structure (82).

2. Cooling device (30) according to claim 1, wherein the cooling device (30) comprises a plurality of sensors (70) and / or a plurality of active thermoregulation elements (60) distributed along at least one conduit (52).

3. Cooling device (30) according to claim 1 or 2, wherein at least one active thermoregulation element (60) comprises at least one electrical resistance or at least one Peltier effect cell.

4. Cooling device (30) according to any one of the preceding claims, wherein at least one active thermoregulation element (60) comprises at least one heating wire (62) integrated into the frame (35) or mounted on the intermediate structure (82) and preferably extending along an external contour of at least one wall (36) or along the duct (52).

5. Cooling device (30) according to any one of the preceding claims, wherein the cooling device comprises at least one sensor (70), comprising at least one of: a temperature sensor, a hydrostatic pressure sensor, a viscosity sensor, and a humidity sensor.

6. Cooling device (30) according to any one of the preceding claims, wherein the cooling device comprises at least one sensor (70), the frame (35) defining at least one housing (72), said housing (72) being configured to receive at least in part one of the at least one sensor (70) and / or one of the at least one active thermoregulation element (60), the frame (35) also defining an access channel (76) extending through the frame (35) from the housing (72) to at least one conduit (52), so as to permit contact between the fluid and the sensor (70) or the active thermoregulation element (60) received in the housing (72).

7. Cooling device (30) according to any one of the preceding claims, wherein the support structure (34) comprises the intermediate structure (82), said intermediate structure (82) comprising a lateral portion (84) and at least one support arm (88) extending from the lateral portion (84) into at least one conduit (52), said support arm (88) carrying at least one active thermoregulation element (60) and, optionally, at least one sensor (70).

8. Cooling device (30) according to claim 7, wherein the lateral portion (84) extends along the lateral edges of at least one wall (36) and forms at least one weld region (38) in which at least one wall (36) is fixed to the intermediate structure (82).

9. Cooling device (30) according to claim 7 or 8, wherein the intermediate structure (82) further comprises a middle portion (86) integral with the lateral portion (84) and forming at least one weld region (38) in which at least one wall (36) is fixed to the intermediate structure (82).

10. Electric battery (10) comprising: - a plurality of battery cells (14) arranged in an enclosure (12), each battery cell (14) having cooling elements arranged on an upper (18), lower (20), or lateral face of the battery cell (14), and - a cooling device (30) according to any one of the preceding claims, the casing (32) being arranged to come into contact with the elements to be cooled when a cooling fluid circulates in at least one conduit (52).

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