A system that cools the drive battery in the event of thermal runaway

Abstract

The system for cooling a traction battery of a motor vehicle includes a charge port (12), a traction battery having at least one power connector secured to a surface, and at least one electrical cable connecting the charge port to the power connector. The system further includes a first plurality of cells (20) disposed about the charge port (12), a conduit disposed about the electrical cable and in fluid communication with the first plurality of cells (20), and a second plurality of cells disposed about the power connector on the surface and in fluid communication with the conduit. The first and second plurality of cells and the conduit are adapted to receive a cooling fluid in the event of thermal runaway of the traction battery.

Description

Summary of the Invention

[0001] The present invention relates to a system for cooling a traction battery in the event of thermal runaway.

[0002] The present invention is in the field of traction batteries for plug-in hybrid or electric motor vehicles.

[0003] Current national regulations are focused on ensuring the safety of vehicle occupants in the event of thermal runaway in traction batteries using lithium-ion technology, and therefore the goal is, among other things, to limit the risk of fire, fire hazard, or gas emissions associated with thermal runaway.

[0004] In a plug-in hybrid or electric vehicle, to reduce the risk of such fires, fire hazards, or gas emissions, it is desirable to "flood" all of the battery components within the battery casing with a coolant to reduce combustion of these components and the surrounding area of ​​the battery.

[0005] It is a known technique to make the nozzle of a fire hose accessible under the rear seat of a vehicle.

[0006] However, that solution has the drawback that it is necessary to wait for the fire to make this part of the vehicle accessible in order to be able to take intervention measures.

[0007] Japanese Patent Publication No. 5849692 further discloses a battery fire extinguishing device that includes access to the battery via an opening and a duct parallel to the vehicle charging circuit.

[0008] However, because the access point to this duct is located in close proximity to the charge port, this increases the risk of confusion and error by the vehicle user when connecting the charge port to a power source.

[0009] SUMMARY OF THE INVENTION An object of the present invention is to overcome the above-mentioned drawbacks of the prior art.

[0010] To this end, the present invention provides a system for cooling a drive battery of a motor vehicle, comprising: Charging port and a drive battery having at least one power connector fixed to one wall surface of the battery; at least one electrical cable connecting the charging port to the power connector; In a system comprising: a first plurality of cellular cavities disposed about the charge port; a duct disposed about the electrical cable and in fluid communication with the first plurality of cellular cavities; a second plurality of cellular cavities in the face, disposed around the power connector and in fluid communication with the duct; Furthermore, The first and second plurality of cellular cavities and ducts are adapted to receive a coolant in the event of thermal runaway of the traction battery. The present invention proposes a system characterized by the above.

[0011] In this way, the present invention allows firefighters faster and more direct access to flood the battery and suppress the fire, while at the same time eliminating the risk of confusion or error on the part of the vehicle user when connecting the vehicle to a power source to recharge the traction battery.

[0012] In one particular embodiment, the first and second pluralities of cellular cavities are closed by a notched cover.

[0013] This allows the cellular cavities to remain closed unless intervention is required, during which time they can deform under the pressure of the coolant jets.

[0014] In one particular embodiment, the cellular cavities of the first plurality of cellular cavities are fabricated from aluminum and the cellular cavities of the second plurality of cellular cavities are fabricated from steel.

[0015] These materials are adapted to the temperature values ​​to which the charging port and the battery, respectively, are susceptible in the event of thermal runaway of the battery.

[0016] In one particular embodiment, the first plurality of cellular cavities are formed in a ring surrounding the charge port.

[0017] During intervention, this allows the coolant to flow all the way around the charge port and cover the entire inner wall of the duct.

[0018] In one particular embodiment, the first plurality of cellular cavities are evenly distributed in the ring.

[0019] This further improves the distribution of the coolant.

[0020] In one particular embodiment, the first and second pluralities of cellular cavities have circular cross-sections.

[0021] This shape is easy to manufacture and allows for good distribution of the coolant.

[0022] With the same objectives as those indicated above, the invention also proposes a plug-in hybrid or electric motor vehicle, characterized in that it comprises a cooling system as briefly described above.

[0023] The advantages and detailed features of that vehicle are the same as those of the cooling system and will not be repeated here.

[0024] Other aspects and advantages of the present invention will become apparent from a reading of the following detailed description of particular embodiments, given entirely by way of non-limiting example, with reference to the accompanying drawings, in which: [Brief explanation of the drawings]

[0025] [Figure 1] 1 is a schematic diagram of a portion of a motor vehicle equipped with a cooling system in one particular embodiment according to the invention; [Figure 2] 1 is a schematic cross-sectional view of a charging port equipped with a cooling system in a particular embodiment according to the invention; [Figure 3] 1 is a schematic diagram of a traction battery equipped with a cooling system in one particular embodiment according to the invention; DETAILED DESCRIPTION OF THE INVENTION

[0026] As shown in FIGS. 1 and 3 , in one particular embodiment, a cooling system for cooling a traction battery 30 of a motor vehicle 10 according to the present invention includes a charge port 12 adapted to connect to a power source for recharging the traction battery of the vehicle 10.

[0027] The cooling system further includes a traction battery 30. The traction battery 30 includes one or more power connectors 34 secured to a surface 36 of a wall of the traction battery 30. In the particular embodiment shown, two power connectors 34 are secured to the surface 36.

[0028] The system further includes one or more electrical cables 14 connecting the charging port 12 to a power connector 34 .

[0029] 2, in accordance with the present invention, the system further comprises a first plurality of cellular cavities 20 arranged around the charging port 12. By way of non-limiting example, in the particular embodiment shown, the first plurality of cellular cavities 20 consists of 17 cellular cavities, all of the same size and circular cross-section. In variations, the cellular cavities may all have some other shape, and do not necessarily all have the same size or shape.

[0030] By way of non-limiting example, the first plurality of cellular cavities 20 may be formed in a ring 22 surrounding the charge port 12. The diameter of the ring 22 is advantageously the same as the diameter of a standard fire hose nozzle. The cellular cavities 20 are advantageously, but not necessarily, evenly distributed around the periphery of the ring 22. The ring 22 may be fabricated from a plastic material that can withstand high temperatures and resist fires that may occur in the event of thermal runaway.

[0031] Optionally, charge port 12 may be equipped with one or more studs 24 for securing a fire hose nozzle directly to charge port 12. This allows firefighters to attach a fire hose nozzle directly to the vehicle in the event of intense heat when it is difficult and too dangerous to remain near the vehicle to suppress the fire. In the particular embodiment shown in FIG. 2, two diametrically opposed studs 24 are provided. Alternatively, securing studs 24 may be replaced by any other device capable of clipping a fire hose nozzle onto charge port 12.

[0032] 1, in accordance with the present invention, the system further comprises a duct 16 (seen in FIG. 1) disposed around the electrical cable 14. The duct 16 is in fluid communication with the first plurality of cellular cavities 20. By way of non-limiting example, the duct 16 may be fabricated from braided fiberglass or a material similar to that of a fire hose nozzle, such as a circular textile made from a twill weave of high tenacity polyester yarns.

[0033] As shown in Figure 3, in accordance with the present invention, the system further includes a second plurality of cellular cavities 32 disposed on a surface 36 of the battery wall around the power connector 34. The surface 36 may be a plate welded to the battery pack or may be part of the battery pack wall. The second plurality of cellular cavities 32 is in fluid communication with the duct 16. By way of a completely non-limiting example, in the particular embodiment shown in Figure 3, the second plurality of cellular cavities 32 consists of 17 cellular cavities, all of the same sized circular cross-section.

[0034] The first and second plurality of cellular cavities 20, 32 and the duct 16 are adapted to receive a coolant, such as water, in the event of thermal runaway of the traction battery 30. That is, the duct 16 delivers the coolant from the charging port 12 to the interior of the traction battery 30.

[0035] The duct 16 can be made from a rigid or flexible material. If it is a flexible material, the duct must nevertheless be able to withstand high pressures when filled with coolant. The material chosen must also be fire-resistant and able to withstand the high temperatures that would occur in the event of a thermal runaway of the traction battery 30.

[0036] The cellular cavities of the first and second pluralities of cellular cavities 20, 32 are closed by covers that are notched so as to deform under the pressure of the coolant jets, for example. By way of reference, the pressure of water released by a fire hose nozzle can be as high as 300 bar.

[0037] As a non-limiting example, the cover of the first plurality of cellular cavities 20 may be made from aluminum or plastic, while the cover of the second plurality of cellular cavities 32 may be made from steel plate, such that the cover of the second plurality of cellular cavities 32 can withstand more heat than the cover of the first plurality of cellular cavities 20.

[0038] The scoring of the cover consists of scoring each cellular cavity to provide a mechanical weakness that allows the cover to deform under the pressure of the coolant jets. By way of non-limiting example, this scoring can be accomplished using laser cutting or water jet cutting, or alternatively, a scoring press.

[0039] As a non-limiting example, but not necessarily as described above, the cellular cavities of the first and second pluralities of cellular cavities 20, 32 may have circular cross-sections, as in the particular embodiment shown in Figures 2 and 3.

Claims

1. A system for cooling a drive battery (30) of an automotive vehicle (10), comprising: a charging port (12); a drive battery (30) having at least one power connector (34) fixed to a wall surface (36) of the battery; at least one electrical cable (14) connecting the charging port (12) to the power connector (34); In a system comprising: a first plurality of cellular cavities (20) disposed around the charging port (12); a duct (16) disposed around the electrical cable (14) and in fluid communication with the first plurality of cellular cavities (20); a second plurality of cellular cavities (32) disposed around the power connector (34) on the face (36) and in fluid communication with the duct (16); Furthermore, The first and second plurality of cellular cavities (20, 32) and the duct (16) are adapted to receive a coolant in the event of thermal runaway of the traction battery (30). A system characterized by:

2. 2. The system of claim 1, wherein said first and second plurality of cellular cavities (20, 32) are closed by a notched cover.

3. 3. The system of claim 2, wherein said cover of said first plurality of cellular cavities (20) is fabricated from aluminum and said cover of said second plurality of cellular cavities (32) is fabricated from steel.

4. 4. The system of claim 1, wherein the first plurality of cellular cavities (20) are formed in a ring (22) surrounding the charging port (12).

5. 5. The system of claim 4, wherein said first plurality of cellular cavities (20) are evenly distributed within said ring (22).

6. 4. The system according to claim 1, wherein said first and second pluralities of cellular cavities (20, 32) are of circular cross section.

7. A plug-in hybrid or electric motor vehicle (10), characterized in that it comprises a cooling system according to any one of claims 1 to 3.

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