MOTOR VEHICLE COMPRISING A BATTERY PACK EQUIPPED WITH AT LEAST ONE VENTILATION PIPE, AND METHOD BASED ON SUCH A VEHICLE

Abstract

The invention relates to a motor vehicle comprising:- a body (C);- a battery pack (P) housed in the body (C), comprising a traction battery equipped with at least one degassing valve (V), characterized in that it further comprises at least one ventilation pipe (T) comprising a first end (E1) arranged on said degassing valve (V), and a second end (E2) opening out of the body (C). The invention also relates to a method based on such a vehicle. Figure 2

Description

Title of the invention: MOTOR VEHICLE COMPRISING A BATTERY PACK EQUIPPED WITH AT LEAST ONE VENTILATION PIPE, AND METHOD BASED ON SUCH A VEHICLE

[0001] The invention relates to the field of batteries for electrified vehicles, i.e. electric, hybrid or hydrogen vehicles. The invention relates more particularly to the evacuation of gases generated by the battery from the battery pack, in particular in cases of thermal runaway.

[0002] Ventilation valves are provided on battery pack housings to vent these gases out of the battery modules. These degassing valves V are illustrated in [Fig.l], as well as a breathing valve VR provided in certain models of the applicant.

[0003] The only known existing solution for managing gases under the vehicle body are deflectors. However, the evacuation of gases from the battery is only partially achieved with little efficiency.

[0004] The defects and / or problems which make current solutions based on deflectors unsatisfactory include recirculation of gases under the body with risks of ignition by incandescent particles, by hot spots by high concentration, as well as risks of smoke entering the passenger compartment.

[0005] An objective of the present invention is to remedy the defects of the prior art, and in particular to propose a solution making it possible to improve the safety and comfort of the user by limiting the risks of gas ignition and smoke entering the passenger compartment.

[0006] To achieve this objective, the invention proposes a motor vehicle comprising: - a body; - a battery pack housed in the body, comprising a traction battery equipped with at least one degassing valve, characterized in that it further comprises at least one ventilation pipe comprising a first end arranged on said degassing valve, and a second end opening out of the box.

[0007] Advantageously, the ventilation tube makes it possible to evacuate the gases at the end of the tube, and thus to avoid ignition of the gases by confinement under the body (regulatory constraint), by projection of incandescent particles (regulatory constraint), and also to avoid the entry of smoke into the passenger compartment by evacuating the gases to the outside (regulatory constraint), as well as thermal risks on the underbody components near ventilation valves.

[0008] Preferably, the motor vehicle comprises two ventilation pipes.

[0009] This makes it suitable for battery packs with two valves.

[0010] Preferably, the battery pack is arranged on a rocker panel of the body, and the second end of said ventilation pipe opens below the rocker panel of the body.

[0011] This makes it suitable for vehicles whose battery is located on the underbody.

[0012] Preferably, said ventilation pipe is sealed around said degassing valve.

[0013] This allows for complete extraction of gases from said valve.

[0014] Preferably, the battery pack forms a closed enclosure, and said ventilation pipe is sealed to the battery pack.

[0015] This allows for complete extraction of gases from the battery pack.

[0016] Preferably, said ventilation pipe is sealed to the body.

[0017] This allows for complete extraction of gases from the body.

[0018] The invention further relates to a method of manufacturing a motor vehicle. according to the invention, characterized in that it comprises the following steps: - an installation step in which the battery pack is housed in the box; and - an assembly step in which at least one ventilation pipe is assembled to the battery pack so that the first end is arranged on said degassing valve, and the second end opens out of the body.

[0019] Preferably, the assembly step comprises an assembly of two ventilation pipes.

[0020] Preferably, in the installation step, the battery pack arranged on a lower body of the body, and in the assembly step, the second end of said ventilation pipe opens below the underbody of the body.

[0021] Preferably, the manufacturing method further comprises at least one sealing step in which said ventilation pipe is sealed around said degassing valve, to the battery pack, and preferably to the body.

[0022] The invention will be further detailed by the description of non-limiting embodiments, and on the basis of the appended figures illustrating variants of the invention, in which: - [Fig.l] schematically illustrates a view in space of a battery pack according to the prior art; - [Fig.2] schematically illustrates a view in space of a battery pack according to the invention; - [Fig.3] schematically illustrates a sectional view of a battery pack according to the invention along the ventilation tube.

[0023] The invention seeks to resolve the ignition of gases at the battery pack P outlet during a thermal runaway event (or "thermal runaway" in English), which may come from incandescent particles, from an excessively high concentration of gas in the underbody C or from recirculation at a hot point.

[0024] To this end, the invention proposes a ventilation pipe device T. This essentially involves adding an exhaust line around the degassing valves V of a battery pack P to evacuate these hot gases (~400°C at the battery pack P outlet) to an area that is not a risk for the user and for the vehicle.

[0025] In particular, the innovation comes from the addition of a part around the degassing valves V with a seal to evacuate the gases efficiently to the outside of the vehicle. The vehicle outlet interface is also important to optimize the evacuation of gases and prevent any recirculation.

[0026] The main advantage of this technical solution is the robustness of its technical performance (gas evacuation). It allows the regulatory constraints at vehicle level linked to thermal runaway to be overcome.

[0027] In particular, the seal of the left zone in [Fig.2], includes the breathing valve VR which can allow hot gases to pass after a certain time during the thermal runaway event.

[0028] The technical solution preferably meets important technical constraints: - be airtight to avoid any recirculation and allow 99% of gases to be evacuated; - limit the loss of charge so as not to modify the degassing behavior of the battery; - treat the outlet of the ventilation tube T and the interface with the body element C of the vehicle to avoid recirculation in the underbody.

[0029] Said ventilation pipe T comprises a first end E1 sealed on said degassing valve V, a part sealed to the box C, and a second end E2 opening out of the box C.

[0030] In particular, the battery pack P forms a closed enclosure, and is arranged on a lower body of the body C.

[0031] Furthermore, the second end E2 of said ventilation pipe T opens below the underbody of the body C.

[0032] The invention further relates to a method comprising steps of positioning and assembling the battery pack and said ventilation pipe T described above.

Claims

Claims

1. Motor vehicle comprising: - a body (C); - a battery pack (P) housed in the body (C), comprising a traction battery equipped with at least one degassing valve (V), characterized in that it further comprises at least one ventilation pipe (T) comprising a first end (El) arranged on said degassing valve (V), and a second end (E2) opening out of the body (C).

2. Motor vehicle according to claim 1, characterized in that it comprises two ventilation pipes (T).

3. Motor vehicle according to any one of claims 1 to 2, in which the battery pack (P) is arranged on a rocker panel of the body (C), characterized in that the second end (E2) of said ventilation pipe (T) opens below the rocker panel of the body (C).

4. Motor vehicle according to any one of claims 1 to 3, characterized in that said ventilation pipe (T) is sealed around said degassing valve (V).

5. Motor vehicle according to any one of claims 1 to 4, in which the battery pack (P) forms a closed enclosure, characterized in that said ventilation pipe (T) is sealed to the battery pack (P).

6. Motor vehicle according to any one of claims 1 to 5, characterized in that said ventilation pipe (T) is sealed to the body (C).

7. Method for manufacturing a motor vehicle according to any one of claims 1 to 6, characterized in that it comprises the following steps: - a positioning step in which the battery pack (P) is housed in the body (C); and - an assembly step in which at least one ventilation pipe (T) is assembled to the battery pack (P) so that the first end (El) is arranged on said degassing valve (V), and the second end (E2) opens out of the body (C).

8. A manufacturing method according to claim 7, characterized in that the assembly step comprises an assembly of two vent pipes- tilation (T).

9. Manufacturing method according to any one of claims 7 to 8, characterized in that in the positioning step, the battery pack (P) is arranged on a bottom of the body of the body (C), and in the assembly step, the second end (E2) of said ventilation pipe (T) opens below the bottom of the body of the body (C).

10. Manufacturing method according to any one of claims 7 to 9, characterized in that it further comprises at least one sealing step in which said ventilation pipe (T) is sealed around said degassing valve (V), to the battery pack (P), and preferably to the body (C).

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