Battery module cooling system

Abstract

Title: Cooling System for a Battery Module The invention relates to a cooling system (1) for a battery module (101) and at least one electronic module (102) such as including a DCDC converter, an inverter or an on-board electric charger, this system comprising: a first branch (2) of dielectric fluid configured to cool the battery module (101) by immersion, a second branch (3) of dielectric fluid configured to cool the electronic module (102) by immersion, and in particular the first (2) and second (3) branches of dielectric fluid are consecutive such that the dielectric fluid is used first to cool the battery module (101), in the first branch (2), then to cool the electronic module(s) (102), in the second branch (3),a heat exchanger (4) configured to allow heat exchange between the dielectric fluid that has circulated in at least one of the first and second branches (2, 3), and a separate heat transfer fluid, in particular a heat transfer fluid from an air conditioning unit (80) of a motor vehicle. Figure for the abstract: Fig. 1,

Description

Title of the invention: Cooling system for a battery module

[0001] The present invention relates in particular to a system for cooling a battery module and at least one electronic module.

[0002] It is known nowadays to equip electric, thermal or hybrid vehicles with electrical energy storage components allowing an electrical supply to the various elements of the vehicle. These electrical energy storage components are generally composed of electrical energy storage cells positioned in a battery pack.

[0003] Car manufacturers are currently seeking to provide more powerful electric or hybrid vehicles with increased electric range. To this end, more and more battery packs, and / or increasingly larger battery packs, are being installed on these electric or hybrid vehicles. It is known to install all or at least some of these battery packs at the floor of the vehicle, substantially across the entire width of the vehicle.

[0004] It is understood that, during operation of the vehicle, the battery packs can release a significant amount of heat and therefore be subject to temperature increases which can in certain cases cause their damage or even their destruction. Consequently, their cooling is essential in order to keep them in good condition and thus ensure the reliability, autonomy and performance of the vehicle.

[0005] In parallel with this need to cool batteries, there is a need to cool electronic components / modules.

[0006] The present invention aims in particular to meet these needs.

[0007] The invention thus relates to a system for cooling a battery module and at least one electronic module such as including a DCDC converter, an inverter or an on-board electrical charger, this system comprising: - a first branch of dielectric fluid configured to cool the battery module by immersion, - a second branch of dielectric fluid configured to cool the electronic module by immersion, and in particular the first and second branches of dielectric fluid follow one another so that the dielectric fluid is used first to cool the battery module, in the first branch, then to cool the electronic module(s), in the second branch, - a heat exchanger configured to allow heat exchange between the dielectric fluid having circulated in at least one of the first and second branch, and a separate heat transfer fluid, in particular a heat transfer fluid of an air conditioning device of a motor vehicle.

[0008] In the present invention, cooling by immersion in dielectric fluid can be carried out by total immersion of the module to be cooled (which is then totally immersed, over its entire height, in dielectric fluid) or, as a variant, by partial immersion of the module to be cooled in the sense that the module is for example immersed over a certain height only, not being totally immersed in dielectric fluid.

[0009] The invention thus proposes to cool both the battery module and the electronic module(s) in the same cooling system, in particular by using the same dielectric fluid. A simplification of the general architecture can thus be envisaged, at the same time as greater compactness. For example, it is possible to integrate electronic modules to be cooled in a battery pack, according to different possible configurations.

[0010] The invention makes it possible to avoid providing a separate cooling circuit (for example using glycolated water) for the electronic modules, different from that for the battery.

[0011] According to one aspect of the invention, the first branch of dielectric fluid passes through a compartment which receives battery cells (which forms the battery module).

[0012] For example, the first dielectric fluid branch begins at the outlet of the heat exchanger and includes nozzles for distributing dielectric fluid into the battery compartment.

[0013] According to another aspect of the invention, the second dielectric fluid branch begins at the fluid outlet of the battery compartment. The second dielectric fluid branch comprises a conduit which carries the dielectric fluid through the electronic modules.

[0014] According to one aspect of the invention, the battery module comprises battery cells at least partially immersed in the dielectric fluid circulating in the first branch.

[0015] According to one aspect of the invention, the battery cells are arranged in a sealed compartment through which the first branch passes so that dielectric fluid fills this compartment sufficiently to immerse the battery cells located therein.

[0016] According to one aspect of the invention, the battery cells are arranged in several sealed compartments through which the first branch passes so that dielectric fluid fills these compartments sufficiently to immerse the battery cells located therein.

[0017] According to one aspect of the invention, these watertight compartments are placed in series or parallel with respect to the flow of dielectric fluid in the first branch.

[0018] According to one aspect of the invention, the battery module(s) are placed on a common base, for example formed of a bottom and side beams.

[0019] According to one aspect of the invention, the base is closed by a cover.

[0020] According to one aspect of the invention, the system comprises configured conduits to fluidly connect the heat exchanger to the air conditioning system.

[0021] According to one aspect of the invention, the heat exchanger is of the plate type.

[0022] According to one aspect of the invention, the air conditioning device is outside the base of the battery cell compartments.

[0023] According to one aspect of the invention, the heat exchanger rests on the base.

[0024] According to one aspect of the invention, the cooling system comprises a single heat exchanger fluidly connected to the air conditioning device, this heat exchanger being common to the first and second dielectric fluid branches.

[0025] In this case, the two branches are part of the same dielectric fluid circuit.

[0026] According to one aspect of the invention, a valve, in particular a multi-way valve, may be provided to regulate the circulation of dielectric fluid in one or other of the hips, or both. For example, the valve may be configured to selectively allow the second branch of dielectric fluid dedicated to the electronic module to be supplied or not.

[0027] Alternatively, the cooling system comprises two heat exchangers fluidically connected to the air conditioning device, these two heat exchangers belonging respectively to the first and second dielectric fluid branches.

[0028] Thus each branch has its own heat exchanger, and the two branches are separated from each other in the sense that these branches do not exchange dielectric fluid.

[0029] According to one aspect of the invention, the electronic modules are placed on the base. Thus, these electronic modules are placed on the same plane as the battery cell compartments, for example all on the same side thereof. Alternatively, the electronic modules are distributed on either side of the battery cell compartments.

[0030] According to another aspect of the invention, at least one of the electronic modules is placed on the battery cell compartment(s). For example, all of the electronic modules are placed on the battery cell compartment(s). In this case, there is a tier of battery cell compartments resting on a base, and a tier of electronic modules resting on the tier of battery cell compartments.

[0031] According to one aspect of the invention, elements of the electronic module are at least partially immersed in the dielectric fluid circulating in the second branch.

[0032] According to one aspect of the invention, the electronic module comprises a casing which contains electrical components and through which the second branch passes so that dielectric fluid fills this casing sufficiently to immerse electrical components located therein.

[0033] According to one aspect of the invention, the second branch is configured to cool several electronic modules, including in particular a DCDC converter, an inverter and an on-board electrical charger. These modules are directly or indirectly electrically connected to the battery modules.

[0034] According to one aspect of the invention, the electronic modules are arranged so as to be cooled in series by the second branch.

[0035] Thus the electronic modules are all arranged in a common area, for example in a common dwelling.

[0036] According to one aspect of the invention, this common housing for electronic modules is attached to a housing receiving the battery module.

[0037] According to one aspect of the invention, these adjoining dwellings are separated by a partition wall.

[0038] According to one aspect of the invention, the electronic modules are received in separate housings, for example arranged on two separate sides of a housing receiving the battery module.

[0039] According to one aspect of the invention, the second branch is configured to cool an electric motor, for example a reversible motor for automobile traction.

[0040] According to one aspect of the invention, the electric motor is placed outside the battery module base. In particular, this electric motor is electrically connected to the inverter.

[0041] According to one aspect of the invention, a heating device, in particular a heating resistor, is provided for heating the dielectric fluid of the first branch. Thus, it is possible to heat the battery cells if necessary.

[0042] According to one aspect of the invention, a filter is provided for filtering the dielectric fluid. The filter can be placed on the common base.

[0043] The invention also relates to an assembly comprising at least one battery module and at least one electronic module, and a cooling system configured to cool the battery module and the electronic module respectively using the first and second branches of the cooling system.

[0044] Other features, details and advantages of the invention will become more apparent clearly upon reading the description which follows on the one hand, and several examples of embodiment given for informational and non-limiting purposes with reference to the attached schematic drawings on the other hand, in which:

[0045] [Fig.l] [Fig.l] is a perspective representation of an assembly according to an exemplary embodiment of the invention, comprising battery modules and an electronic module, with a cooling system;

[0046] [Fig.2] [Fig.2] is a perspective representation of one set according to another exemplary embodiment of the invention;

[0047] [Fig.3] [Fig.3] is a perspective representation of a set according to still another example of an embodiment of the invention;

[0048] [Fig.4] [Fig.4] is a perspective representation of one set according to another exemplary embodiment of the invention;

[0049] [Fig.5] [Fig.5] is a perspective representation of one set according to another exemplary embodiment of the invention.

[0050] The features, variants and different embodiments of the invention may be combined with each other, in various combinations, provided that they are not incompatible or mutually exclusive. In particular, variants of the invention may be imagined comprising only a selection of features described below in isolation from the other features described, if this selection of features is sufficient to confer a technical advantage and / or to differentiate the invention from the prior art.

[0051] [Fig. 1] shows an assembly 100 comprising battery modules 101 and an electronic module 102, as well as a cooling system 1 configured to cool the battery modules 101 and the electronic module 102. The battery cells of the battery modules 101 are, for example, of the lithium-ion type. Other types of battery can of course be envisaged. The assembly is intended to be mounted on a motor vehicle. The electronic module comprises, for example, a DCDC converter and / or an inverter and / or an electronic part of an on-board electrical charger.

[0052] The cooling system 1 comprises: - a first branch 2 of dielectric fluid configured to cool by immersion the battery modules 101, - a second branch 3 of dielectric fluid configured to cool by immersion the electronic module 102, and the first branch 2 and second branch 3 of dielectric fluid follow one another so that the dielectric fluid is used first to cool the battery modules 101, in the first branch 2, then to cool the electronic module 102, in the second branch 3, - a heat exchanger 4 configured to allow heat exchange between the dielectric fluid having circulated in the first and second branches 2 and 3, and a separate heat transfer fluid, here a heat transfer fluid of an air conditioning device 80 of a motor vehicle.

[0053] Branches 2 and 3 are shown in dotted lines in [Fig.l].

[0054] The first branch 2 passes through a base 9 which receives the battery modules 101. This first branch 2 passes through the heat exchanger 4 and comprises dielectric fluid distribution / evacuation nozzles connected to connectors 11 of the sealed compartments 12 (or sealed housings) of the battery modules 101. The dielectric fluid immerses the battery cells contained in these modules 101, before being evacuated and returned to the circulation of branch 1.

[0055] Several sealed compartments 12 are arranged in a row on the base 9, and the first branch 2 supplies these compartments 12 in parallel with dielectric fluid.

[0056] The battery modules 101 are placed on the common base 9, formed of a bottom 14 and side beams 15.

[0057] The base 9 is closed by a cover, not shown.

[0058] The system 1 comprises conduits 16 configured to fluidly connect the heat exchanger 4 to the air conditioning device 80.

[0059] The heat exchanger 4 is of the plate type, and rests on the base 9.

[0060] The air conditioning device 80 is outside the base 9 of the compartments 12 of battery cells.

[0061] In the example described, the cooling system 1 comprises a single heat exchanger 4 fluidly connected to the air conditioning device 80, this heat exchanger 4 being common to the first and second branches 2 and 3 of dielectric fluid.

[0062] In this case, the two branches 2 and 3 are part of the same dielectric fluid circuit.

[0063] The electronic module 102 and the heat exchanger 4, as well as a pump 19 for circulating the fluid in the branches 2 and 3, are placed on the bottom 14 of the base 9. Thus these elements are placed on the same plane as the compartments 12 of battery cells 101.

[0064] The electronic module 102, on the one hand, and the heat exchanger 4 and the pump 19, on the other hand, are distributed on either side of the compartments 12 of battery cells 101.

[0065] The electronic module 102 comprises a casing 21 which contains electrical components in a sealed manner and in which the second branch 3 passes so that dielectric fluid fills this casing 21 sufficiently to immerse components electrical components located therein. This casing 21 includes fluid connection pipes 23 for connecting the second branch 2 to the module 102.

[0066] The electronic module 102 is separated from the battery modules 101 by a partition 22.

[0067] Branches 2 and 3 include pipes to make the fluid connections between the different elements, and are shown by dotted lines in fig 1.

[0068] The second branch 3 is configured to cool an electric motor 25, for example a reversible motor to participate in automobile traction.

[0069] The electric motor 25 is placed outside the base 9. In particular, this electric motor is electrically connected to the inverter.

[0070] A heating device 26, in particular a heating resistor, is provided for heating the dielectric fluid of the first branch 2. This heating device 26 is arranged downstream of the heat exchanger 4.

[0071] In another exemplary embodiment of the invention illustrated in [Fig. 2], a valve 30, in particular a multi-way valve, can be added to regulate the circulation of dielectric fluid in one or other of the hips 2 and 3, or both. For example, the valve 30 is configured to selectively allow the second branch 3 to be supplied with dielectric fluid dedicated to the electronic module 102 or not.

[0072] Thus the valve 30 can take a position in which the dielectric fluid is conducted into a bypass 31 while the branch 3 is closed by the valve. This case applies for example when there is no need for cooling of the electronic module 102, or it is not desirable to use cooling capacity in the electronic module to leave the full cooling capacity for the batteries.

[0073] When it is desirable to cool the electronic module 102, the valve 30 is actuated to close the bypass 31 and send dielectric fluid into the branch 3.

[0074] An additional pump 33 is placed in branch 3 upstream of motor 25, to assist the circulation of fluid in this branch 3.

[0075] In the example illustrated in [Fig. 3], the electronic modules 102 are placed on the battery modules 101. For example, all the electronic modules 102 are placed on battery modules 101. In this case, there is a stage of battery modules 101 resting on the base 9, and a stage of electronic modules 102 resting on the stage of battery modules 101.

[0076] In the example illustrated in [Fig.4], compared to [Fig.3], one of the electronic modules 102 is moved onto the base 9 and is not located on top of the battery modules 101. Other arrangements can of course be envisaged.

[0077] In another example illustrated in [Fig.5], the cooling system comprises two heat exchangers 4 and 44 fluidly connected to the air conditioning device 80, these two heat exchangers belonging respectively to the first branch 2 and second branch 3 of dielectric fluid.

[0078] Thus each branch 2 and 3 has its own heat exchanger 4 and 44, and the two branches 2 and 3 are separated from each other in the sense that these branches do not exchange dielectric fluid.

[0079] A control valve 45 is provided on the fluid path coming from the air conditioning device 80.

[0080] The electronic modules 102 are arranged so as to be cooled in series by the second branch 3.

Claims

Claims

1. Cooling system (1) for a battery module (101) and at least one electronic module (102) such as including a DCDC converter, an inverter or an on-board electrical charger, this system (1) comprising: - a first branch (2) of dielectric fluid configured to cool the battery module (101) by immersion, - a second branch (3) of dielectric fluid configured to cool the electronic module (102) by immersion, and in particular the first (2) and second (3) branches of dielectric fluid follow one another so that the dielectric fluid is used first to cool the battery module (101), in the first branch (2), then to cool the electronic module(s) (102), in the second branch (3), - a heat exchanger (4) configured to allow heat exchange between the dielectric fluid having circulated in at least one of the first and second branches (2, 3),and a separate heat transfer fluid, in particular a heat transfer fluid of an air conditioning device (80) of a motor vehicle.,

2. Cooling system (1) according to the preceding claim, in which battery cells are arranged in a sealed compartment (12) in which the first branch (2) passes so that dielectric fluid fills this compartment (12) sufficiently to immerse the battery cells located therein.

3. Cooling system (1) according to claim 1, wherein battery cells are arranged in several sealed compartments (12) and these sealed compartments (12) are placed in series or in parallel with respect to the flow of dielectric fluid in the first branch (2).

4. Cooling system (1) according to one of the preceding claims, in which the battery module(s) (101) are placed on a common base (9), for example formed of a bottom (14) and side beams (15).

5. Cooling system (1) according to one of the preceding claims- preceding, in which the cooling system (1) comprises a single heat exchanger (4) fluidically connected to the air conditioning device, this heat exchanger (4) being common to the first and second branches (2, 3) of dielectric fluid.

6. Cooling system (1) according to one of claims 1 to 4, wherein the cooling system (1) comprises two heat exchangers (4) fluidically connected to the air conditioning device, these two heat exchangers (4) belonging respectively to the first (2) and second (3) dielectric fluid branches.

7. Cooling system (1) according to one of the preceding claims, wherein the at least one electronic module (102) is placed on the at least one battery cell compartment (12).

8. Cooling system (1) according to one of the preceding claims, in which the electronic module (102) comprises a casing (21) which contains electrical components and in which the second branch (3) passes so that dielectric fluid fills this casing (21) sufficiently to immerse electrical components located therein.

9. Cooling system (1) according to one of the preceding claims, wherein the second branch (3) is configured to cool an electric motor (25).

10. Assembly (100) comprising at least one battery module (101) and at least one electronic module (102), and a cooling system (1) according to one of the preceding claims, configured to cool the battery module (101) and the electronic module respectively using the first and second branches (2, 3) of the cooling system.

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