Fluid drainage system for a motor vehicle arrangement.
A tubular fluid evacuation system for electric vehicles deploys to rapidly remove toxic gases from thermal runaway lithium batteries, addressing safety concerns by preventing gas entry into the passenger compartment.
Patent Information
- Authority / Receiving Office
- FR · FR
- Patent Type
- Applications
- Current Assignee / Owner
- RENAULT SA
- Filing Date
- 2024-12-16
- Publication Date
- 2026-06-19
AI Technical Summary
Thermal runaway in lithium batteries of electric or hybrid vehicles poses a significant safety risk due to rapid temperature increase, potential cell rupture, and release of toxic gases or fumes that can compromise passenger safety.
A fluid evacuation system with a tubular structure that deploys from a retracted to a deployed configuration when a pressure threshold is exceeded, using a flexible, impermeable, and non-flammable material to rapidly evacuate toxic gases or fumes away from the battery and prevent their entry into the passenger compartment.
The system effectively limits temperature rise and prevents toxic gases from entering the passenger compartment, ensuring safety by rapidly evacuating hazardous substances.
Smart Images
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Abstract
Description
Title of the invention: Fluid evacuation system for a motor vehicle arrangement.
[0001] The invention relates to an arrangement for an electric or hybrid motor vehicle with a fluid evacuation system.
[0002] The invention also relates to an electric or hybrid motor vehicle comprising such an arrangement.
[0003] The use of a battery in an electric or hybrid motor vehicle requires the implementation of various safety systems. Among the dangers associated with the use of a battery, and in particular a lithium battery, thermal runaway requires special attention.
[0004] Thermal runaway is a fairly common and particularly dangerous phenomenon. It is characterized by a rapid and uncontrolled increase in battery temperature. This phenomenon is generally triggered by an internal short circuit, overcharging, physical damage, a manufacturing defect, or improper use. The temperature increase causes internal chemical reactions such as the decomposition of electrolytes or reactions between the electrodes, which contribute to increased heat production. When the temperature reaches a certain threshold, the battery structure can begin to degrade, potentially leading to cell rupture. Furthermore, battery runaway can cause the release of toxic gases or fumes that can cause a fire.
[0005] The object of the invention is to quickly evacuate these toxic gases or fumes to limit the temperature rise while preventing these gases from entering the passenger compartment of the motor vehicle, which would compromise the safety of the driver and any passengers.
[0006] To this end, the invention relates to an arrangement for an electric or hybrid motor vehicle, the arrangement comprising a battery, in particular a lithium battery, the arrangement being characterized in that it comprises a fluid evacuation system, in particular a gas evacuation system, the evacuation system being intended to be mounted on the battery of the arrangement, the evacuation system comprising a tubular structure configured to deploy longitudinally between a retracted configuration and a deployed configuration when a predetermined pressure threshold is crossed inside the battery arranged upstream of the tubular structure of the evacuation system.
[0007] According to one embodiment, the tubular structure of the drainage system is flattened when said tubular structure is in its retracted configuration.
[0008] According to one embodiment, the tubular structure of the drainage system is wound upon itself when said tubular structure is in its retracted configuration.
[0009] According to one embodiment, the tubular structure comprises a waterproof and / or non-flammable material.
[0010] According to one embodiment, the evacuation system includes a retaining element configured to maintain the tubular structure in its retracted configuration as long as the pressure upstream of said tubular structure is below the predetermined pressure threshold.
[0011] According to one embodiment, the evacuation system includes an elastic return element configured to cooperate with the tubular structure of said evacuation system so as to assist the deployment of the tubular structure between its retracted configuration and its deployed configuration.
[0012] According to one embodiment, the arrangement includes a guide element configured to orient the tubular structure along a predetermined deployment direction.
[0013] According to one embodiment, the guide element is in the form of a hollow elbow in contact with an external wall of the tubular structure of the drainage system.
[0014] According to one embodiment, the same part is configured to perform on the one hand the function of a guiding element and on the other hand the function of a retaining element.
[0015] The invention also relates to a vehicle equipped with such an arrangement.
[0016] These objects, features and advantages of the present invention will be described in detail in the following description of a particular embodiment, given by way of non-limiting example, with reference to the accompanying figures, among which:
[0017] Fig. 1 schematically illustrates a first embodiment of the arrangement in which the tubular structure of the evacuation system is in its retracted configuration.
[0018] Fig.2 is a figure similar to Fig.1, except that the tubular structure of the evacuation system is in its deployed configuration.
[0019] Fig. 3 schematically illustrates a second embodiment of the arrangement in which the tubular structure of the drainage system is in its retracted configuration.
[0020] Fig. 4 schematically illustrates a third embodiment of the arrangement in which the tubular structure of the drainage system is in its retracted configuration.
[0021] Fig. 5 is a figure similar to Fig. 4, except that the tubular structure of the evacuation system is in its deployed configuration.
[0022] Fig. 6 schematically illustrates a variant of the third embodiment of the arrangement in which the tubular structure of the evacuation system is in its retracted configuration.
[0023] In all the embodiments described below, arrangement 1 includes at least one battery 12, in particular a lithium battery 12. The battery 12 is generally located in the floor of the vehicle 10, between the front and rear axles, as illustrated in [Fig. 1]. Alternatively, the battery 12 may be located in the floor of the vehicle 10, between the rear wheels 11 of the vehicle 10.
[0024] The arrangement 1 also includes a fluid, in particular gas, drainage system 14. The drainage system 14 is intended to be mounted on the battery 12 of the arrangement 1.
[0025] Figure 1 is a schematic representation of a first embodiment of the arrangement 1 for an electric or hybrid vehicle 10. In this first embodiment, the drainage system 14 is mounted directly on the battery 12. Alternatively, the drainage system 14 can be mounted on one or more connecting pieces 13 (illustrated in Figure 6) which provide a sealed connection between the drainage system 14 and the battery 12.
[0026] The choice of location for the drainage system 14 in the arrangement 1 depends primarily on the position of the battery 12 within the vehicle 10 and the available space around said battery 12. A location that promotes a compact structure of the arrangement 1 is preferred, as illustrated in Figures 1 to 5. In particular, an arrangement 1 that prevents the drainage system 14 from being too close to the ground is preferred. Thus, an arrangement 1 in which the fluid drainage system 14 is, for example, integrated into the underbody of the vehicle 10, near the battery 12, as illustrated in Figures 1 to 5, is preferred.
[0027] However, when the available space around battery 12 is too limited, it is possible to consider an embodiment in which the evacuation system 14 is offset from battery 12, and therefore located at a distance from it, as illustrated in [Fig.6] for example.
[0028] The drainage system 14 comprises a tubular structure 16 which may be likened to a tube, pipe, or conduit. The geometry of this tubular structure 16, in particular its length, diameter, wall thickness, etc., is intrinsically linked to the location of said tubular structure 16 relative to the battery 12 equipped with such a drainage system 14.
[0029] The diameter of the tubular structure 16 is, for example, on the order of ten millimeters; it may, for example, be between 50 and 60 mm. The length of the The length of tubular structure 16, for example, can range from a few tens of centimeters to several meters. Specifically, the length of tubular structure 16 can range from 50 cm to 2 m, and more particularly from 1 m to 1.5 m, or even up to 1.2 m. The wall thickness of tubular structure 16 is, for example, on the order of a millimeter. The wall thickness of tubular structure 16 can range from 1 to 5 mm.
[0030] According to a preferred embodiment, the tubular structure 16 of the evacuation system 14 comprises an impermeable and / or non-flammable material.
[0031] In this preferred embodiment, the tubular structure 16 is "impermeable" in the sense that it is configured to conduct a fluid from an inlet point to an outlet point without allowing any gas and / or liquid to pass through its wall. In other words, the material(s) of the tubular structure 16 of the drainage system 14 give it sealing properties.
[0032] The tubular structure 16 can be "non-flammable" in the sense that it is specifically configured to withstand very high temperatures, such as temperatures exceeding 250°C. Thus, according to a preferred embodiment, the tubular structure 16 comprises a material that degrades very little when in contact with flames or very hot gases.
[0033] The tubular structure 16 of the evacuation system 14 is configured to deploy longitudinally between a retracted and a deployed configuration when a predetermined pressure threshold is exceeded inside the battery 12 arranged upstream of the tubular structure 16 of the evacuation system 14. "Longitudinally" here means that the tubular structure 16 deploys primarily along its length. In its deployed configuration, the tubular structure 16 may be in contact with the ground on which the vehicle 10 is placed.
[0034] Examples of a retracted configuration of the tubular structure 16 of the drainage system 14 are illustrated in Figures 1, 3, 4 and 6. Examples of a deployed configuration of the tubular structure 16 of the drainage system 14 are illustrated in Figures 2 and 5.
[0035] The material of the tubular structure can be flexible to facilitate deployment between the retracted and deployed configurations. The term "flexible" here refers to the ability of a material to bend, without breaking, within a range of deformation suitable for its intended use. The tubular structure 16, comprising such a flexible material, is therefore capable of being deformed without breaking in order to adapt to the circumstances of its use.
[0036] When a battery 12 runaway occurs and a pressure increase in the gases inside the battery 12 takes place, a predetermined pressure threshold A pressure threshold is exceeded at a certain point inside the battery 12. This predetermined pressure threshold is, for example, 0.4 bar above atmospheric pressure, but other values can be considered for this threshold. When this threshold is exceeded, the gases leave the battery 12 and enter the conduit formed by the tubular structure 16. The structure then leaves its retracted position and adopts a deployed configuration. In other words, when the predetermined pressure threshold is exceeded, the tubular structure 16 of the exhaust system 14 inflates under the effect of the gases rushing into said tubular structure 16, which has the effect of deploying it.
[0037] In its deployed configuration, the tubular structure 16 allows for the rapid evacuation of toxic gases or fumes caused by the thermal runaway of the battery 12. Thanks to this deployed configuration of the tubular structure 16, the evacuation system 14 makes it possible to limit the temperature rise in the enclosure of the battery 12 while preventing the entry of toxic gases or fumes into the passenger compartment of the vehicle 10.
[0038] Preferably, the enclosure of the battery 12 of the arrangement 1 may include a valve (not shown in the figures) opposite the tubular structure 16 of the exhaust system, a valve which remains closed as long as the pressure inside the enclosure of the battery 12 is below the predetermined pressure threshold. The valve opens and clears the passage to the exhaust system 14 when the predetermined pressure threshold is exceeded. In this embodiment, the tubular structure 16 of the exhaust system 14 is connected to the battery 12 so as to be downstream of said battery 12 with reference to the direction of gas flow inside the tubular structure 16.
[0039] According to a preferred embodiment, the tubular structure 16 of the drainage system 14 is flattened when said drainage system 14 is in its retracted configuration. In other words, the tubular structure 16 is sufficiently flexible to deflate when the drainage system 14 is in its retracted configuration; ideally, there is then an absence of gas inside said tubular structure 16. In particular, sections of the inner face of the wall of the tubular structure 16 are pressed together so as to be in contact with each other. A flattened tubular structure 16 ensures advantageous compactness of the drainage system 14 when it is not in use.
[0040] Furthermore, the flattening of the tubular structure 16 of the drainage system 14 prevents foreign bodies such as dirt, water, dust, animals like insects, or other pollutants from entering said drainage system 14. This prevents obstruction of the tubular structure 16, which prevents degradation of the drainage system 14 in its retracted configuration.
[0041] In the embodiment described above, the deployment of the tubular structure 16 is both longitudinal and radial, in the sense that it deploys along its length while inflating in a radial direction under the effect of the gases which rush into said tubular structure 16 of the evacuation system 14.
[0042] To further optimize the compactness of the drainage system 14, the tubular structure 16 of the drainage system 14 can also be rolled up in its retracted configuration. This is illustrated in particular in Figures 1, 3, 4 and 6. Rolling the tubular structure 16 up also ensures advantageous compactness of the drainage system 14 when it is not in use. Alternatively, according to an embodiment not shown, the tubular structure 16 of the drainage system 14 can be folded differently, for example, like an accordion bellows.
[0043] In the embodiment in which the tubular structure 16 is flattened and / or rolled up in its retracted configuration, the tubular structure 16 unrolls and inflates under the effect of gases rushing inside said tubular structure 16 to adopt its deployed configuration. In this particular embodiment, the deployment of the tubular structure 16 is then similar to an unrolling of said structure 16.
[0044] According to a preferred embodiment, the drainage system 14 includes a retaining element 17 configured to maintain the tubular structure 16 in its retracted configuration as long as the pressure upstream of said tubular structure 16 is below the predetermined pressure threshold. This retaining element 17 may, in particular, take the form of a box inside which the tubular structure 16 is arranged, as illustrated in Figures 1 and 2. The box includes, for example, a lid that maintains the tubular structure 16 in its retracted configuration, as illustrated in [Fig. 1], the lid being configured to open like a flap when the tubular structure 16 leaves its retracted configuration to assume its deployed configuration, as illustrated in [Fig. 2].
[0045] Alternatively, the retaining element 17 may be in the form of a clamp, a clip, a wire tied around the tubular structure 16, or any other retaining means. Various embodiments of the retaining element 17 are illustrated in the figures. When the predetermined pressure threshold is exceeded, the retaining element 17 yields under pressure and the tubular structure 16 moves from its retracted configuration to its deployed configuration. The retaining element 17 may, in particular, open or break. The retaining element 17 may be a single-use element.
[0046] In a preferred embodiment, the entire drainage system 14 is a single-use system. In this embodiment, the retaining element 17 can then break irreversibly when the predetermined pressure threshold is exceeded. The retaining element 17 can then serve as an indicator to assess the state of the drainage system 14. Similarly, the tubular structure 16 can be configured so that once it has adopted its deployed configuration, it does not retract into its retracted configuration. In this embodiment, if the single-use drainage system 14 has been used only once, it must be replaced to continue operating the electric vehicle safely.
[0047] According to a complementary or alternative embodiment, the evacuation system 14 may include an elastic return element (not shown in the figures) configured to cooperate with the tubular structure 16 of said evacuation system 14 so as to assist the deployment of the tubular structure 16 between its retracted configuration and its deployed configuration.
[0048] The elastic return element can, for example, take the form of a spring placed inside the cavity of the tubular structure 16. Alternatively, the elastic return element can, for example, be integrated inside the wall of the tubular structure 16 itself. In this alternative, the elastic return element can, for example, be overmolded by the wall of the tubular structure 16 of the drainage system 14, or the wall of the tubular structure 16 can comprise at least two distinct layers and the elastic return element is then disposed at the interface between said layers during the manufacture of the tubular structure 16.
[0049] In the case where the tubular structure 16 is wound on itself when the evacuation system 14 is in its retracted configuration, the presence of an elastic return element makes it possible in particular to participate in the unwinding of the tubular structure 16, thus making the change of configuration faster and more efficient.
[0050] The deployment direction depends on the location of the evacuation system 14 relative to the battery 12 and the model of the vehicle 10 equipped with such an arrangement 1. In a simple embodiment, the tubular structure 16 of the evacuation system 14 deploys in a single deployment direction, for example, in a direction parallel to the longitudinal axis of the vehicle 10, i.e., rearward or forward, or in a direction perpendicular to the longitudinal axis of the vehicle 10, i.e., toward the lateral sides of the vehicle 10. An example of such a single deployment direction is illustrated, for example, in [Fig. 2].
[0051] Alternatively, the deployment of the tubular structure 16 between its retracted and deployed configurations can occur in a plurality of directions deployment, for example along two distinct directions taken one after the other. In other words, an embodiment in which the tubular structure 16 undergoes a change of direction during its deployment is conceivable.
[0052] An example of such an embodiment of the evacuation system 14 is illustrated in [Fig. 5]. In [Fig. 5], the tubular structure 16 first extends in a direction parallel to the longitudinal axis of the vehicle 10, and then in a direction perpendicular to the longitudinal axis of the vehicle 10. In this example, the tubular structure 16 then has a 90° bend in its extended configuration. Other extensions can be considered for the tubular structure 16. Similarly, different angles and / or different radii of curvature can be considered for the tubular structure 16 in its extended configuration.
[0053] To allow a change in the deployment direction of the tubular structure 16 of the drainage system 14, the arrangement 1 may include a guide element 18 configured to orient the tubular structure 16 along a predetermined deployment direction. This guide element 18 may be in the form of a hollow elbow in contact with an external wall of the tubular structure 16 of the drainage system 14, as illustrated in Figures 5 and 6. The guide element 18 is then a separate part of the tubular structure 16.
[0054] However, in order to optimize the compactness of the arrangement 1, the same part can perform both the function of a guiding element 18 and the function of a retaining element 17. Such an embodiment can prove to be economical in addition to being more compact. This embodiment is illustrated in particular in [Fig. 4].
[0055] In addition or alternatively, the tubular structure 16 of the drainage system 14 can be designed such that at least a portion of a wall of the tubular structure 16 includes a reinforcing element configured to induce a variation in the deployment direction of the tubular structure 16 when it adopts its deployed configuration. In other words, it is possible to consider an embodiment in which a reinforcing element in the wall of the tubular structure 16 participates in the guiding function, partially or totally.
[0056] Thus, in the case where the tubular structure 16 is coiled upon itself when the drainage system 14 is in its retracted configuration, the reinforcing element can be integrated into the wall of the tubular structure 16, for example, in the form of a wall that is thicker or thinner in certain places, so as to give the tubular structure 16 a curved or angled shape in its deployed configuration. Furthermore, this reinforcing element can contribute to the stabilization and / or robustness of the tubular structure 16 in its deployed configuration. The reinforcing element is not shown in the figures.
[0057] It is thus possible to design a compact evacuation system 14 for an electric or hybrid motor vehicle 10 to allow the rapid evacuation of toxic gases or fumes caused by a thermal runaway of the battery 12 of said vehicle 10.
Claims
Demands
1. Arrangement (1) for an electric or hybrid motor vehicle (10), the arrangement comprising a battery (12), in particular a lithium battery (12), the arrangement being characterized in that it comprises a fluid, in particular gas, discharge system (14), the discharge system (14) being intended to be mounted on the battery (12) of the arrangement, the discharge system (14) comprising a tubular structure (16) configured to deploy longitudinally between a retracted configuration and a deployed configuration when a predetermined pressure threshold is exceeded inside the battery (12) arranged upstream of the tubular structure (16) of the discharge system (14).
2. Arrangement according to claim 1, characterized in that the tubular structure (16) of the evacuation system (14) is flattened when said tubular structure (16) is in its retracted configuration.
3. Arrangement according to any one of the preceding claims, characterized in that the tubular structure (16) of the drainage system (14) is wound upon itself when said tubular structure (16) is in its retracted configuration.
4. Arrangement according to any one of the preceding claims, characterized in that the tubular structure (16) comprises an impermeable and / or non-flammable material.
5. An arrangement according to any one of the preceding claims, characterized in that the evacuation system (14) includes a retaining element (17) configured to maintain the tubular structure (16) in its retracted configuration as long as the pressure upstream of said tubular structure (16) is below the predetermined pressure threshold.
6. An arrangement according to any one of the preceding claims, characterized in that the evacuation system (14) comprises an elastic return element configured to cooperate with the tubular structure (16) of said evacuation system (14) so as to assist the deployment of the tubular structure (16) between its retracted configuration and its deployed configuration.
7. An arrangement according to any one of the preceding claims, characterized in that it comprises a guiding element (18) configured to orient the tubular structure (16) along a predetermined deployment direction.
8. Arrangement according to the preceding claim, characterized in that the guide element (18) is in the form of a hollow elbow in contact with an external wall of the tubular structure (16) of the evacuation system (14).
9. Arrangement according to claim 5 and claim 7 or 8, characterized in that the same part is configured to provide on the one hand the function of a guiding element (18) and on the other hand the function of a retaining element (17).
10. Motor vehicle (10) characterized in that it comprises an arrangement (1) according to any one of the preceding claims.