Motor vehicle traction battery provided with a valve protection cover

Abstract

The invention relates to a motor vehicle traction battery (20) comprising: -a tray (22) containing battery cells; - at least one valve (38, 40) arranged in a vertical wall (30) of the tray (22); - and a protective cover (54) secured against an outer face (58) of the vertical wall (30) and covering the at least one valve (38, 40); characterised in that the cover (54) comprises at least one lower rim (62) having a free end edge (63) in contact with the outer face (58) of the vertical wall (30) and intended to intercept a jet of water directed toward the at least one valve (38, 40), the lower rim (62) comprising water drainage openings (65).

Description

MOTOR VEHICLE TRACTION BATTERY EQUIPPED WITH A VALVE PROTECTION COVER Technical field of the invention

[0001] The invention relates to a motor vehicle traction battery comprising:

[0002] - a container containing electric accumulators;

[0003] - at least one valve which is arranged in a vertical wall of the tank;

[0004] - a protective cover which is fixed against an external face of said vertical wall, covering the at least one valve. Technical background

[0005] Motor vehicles powered by an electric motor, such as hybrid vehicles or electric vehicles, have a traction battery that is sized to power the electric traction motor.

[0006] Such a motor vehicle is equipped with a traction battery that is arranged under the vehicle chassis. The traction battery is, for example, suspended inside a housing open towards the bottom of the vehicle structure, with little lateral play, so that the underside of the battery pack constitutes an underside of the vehicle. This makes it easier to install and remove the battery packs.

[0007] According to another known design, the traction battery is suspended on rigid elements of the chassis, such as a structural cross member, by direct attachment to the battery tray. The chassis then does not have a housing.

[0008] Such a traction battery contains electric accumulators which are enclosed in a container. The container is tightly closed to prevent substances harmful to the accumulators from entering the container.

[0009] When using the traction battery, the electric accumulators emit volatile substances that gradually accumulate in the tank. This causes a gradual increase in pressure inside the tank. If the pressure becomes too high, there is a risk of damage or even explosion of the traction battery.

[0010] To avoid this problem, the battery tray is usually equipped with safety valves, often referred to by its English acronym "PRV" meaning "Pressure Relief Valve", which open under the effect of the internal pressure in the tray to open a hole allowing volatile substances to escape outside the tray.

[0011] The traction battery advantageously comprises two safety valves, for example a first valve called "PRD" meaning in English "Pressure Release Device" and a second valve produced by the company "NITTO". A first valve opens under the effect of heat and a second valve opens under the effect of internal pressure.

[0012] The valves are arranged in a vertical wall of the battery. To function efficiently, the valves open into a free space between the battery and neighboring components. This free space opens directly below the vehicle. The valves are thus freely accessible from underneath the vehicle. The valves are therefore exposed to splashes when the vehicle is moving, particularly of liquids. This is generally not a problem since the valves have an annular seal, in particular a lip seal, which ensures the sealing of the opening they close when closed.

[0013] Furthermore, it is known to use a high-pressure cleaning device that propels high-pressure water jets for cleaning motor vehicles. For example, the water is compressed to between 80 and 150 bars before being emitted as a jet.

[0014] The exposed traction battery valves are at risk of being impacted by a high-pressure water jet. Typically, a valve flap covers the seals, protecting them when the water jet is emitted perpendicular to the wall that carries the valves.

[0015] However, it has been found that when a high-pressure water jet is emitted in a direction inclined relative to a direction orthogonal to the wall containing the valves, it is likely to directly reach the valve seal. In this case, the pressure of the water jet is sufficient to deform the seal and cause water to penetrate inside the traction battery. This risks damaging the electric accumulators present in the tank.

[0016] It is already known, from document FR-2.987.807-A1, to arrange a horizontal fairing under the vehicle chassis in order to improve the aerodynamics of the vehicle by closing all the gaps present around the battery. Such a fairing extends in the extension of a lower face of the traction battery tray. Such a fairing makes it possible to enclose the battery and thus prevent high-pressure water jets from reaching the valves.

[0017] However, such a fairing is formed by a bulky part of complex shape which is expensive to manufacture and install on the vehicle. Such a solution is therefore very expensive.

[0018] The fairing must always be fitted and removed when the battery is already fitted under the chassis.

[0019] There is therefore a need to effectively and inexpensively prevent water from entering the battery through the valves.

[0020] The invention relates to a motor vehicle traction battery comprising:

[0021] - a container containing electric accumulators;

[0022] - at least one valve which is arranged in a vertical wall of the tank;

[0023] - a protective cover which is fixed against an external face of said vertical wall by covering the at least one valve;

[0024] characterized in that the cover comprises at least one lower rim, a free end edge of which is in contact with the external face of the vertical wall and which is intended to intercept a jet of water directed towards the at least one valve, the lower rim comprising water discharge orifices.

[0025] According to another characteristic of the invention, the hood comprises an internal face equipped with at least one deflector which is interposed between the discharge orifices and the at least one valve, the deflector being intended to intercept a jet of water passing through the discharge orifices and directed towards the at least one valve.

[0026] According to another characteristic of the invention, the deflector is formed by a rib which extends from the internal face of the cover towards the vertical wall of the tank.

[0027] According to another characteristic of the invention, said vertical wall comprises two valves, said cover simultaneously covering the two valves, for example the “PRD” valve and the “NITTO” valve.

[0028] According to another characteristic of the invention, at least one deflector is interposed between the discharge orifices and each of the two valves.

[0029] According to another characteristic of the invention, the hood comprises a single deflector which is interposed between the discharge orifices and each of the two valves. This deflector makes it possible in particular to prevent the penetration of a jet of pressurized water towards the valves.

[0030] According to another characteristic of the invention, the cover is made of a plastic material.

[0031] According to another characteristic of the invention, the cover is made in a single piece by molding. The cover is for example made of plastic.

[0032] According to another characteristic of the invention, the vertical wall is made of an external envelope comprising the external face and an internal partition separated by an air gap, the cover being fixed to the vertical wall by means of a nut fixed in the external envelope and a threaded rod which penetrates into the air gap without passing through the internal partition.

[0033] According to another characteristic of the invention, the vertical wall of the tank is equipped with two vertical bearing faces facing each other and projecting orthogonally relative to the vertical wall between which the cover is received, the cover comprising an elastically flexible free end tab making it possible to hold the cover between the two bearing faces by clamping. This characteristic makes it possible to hold the cover in position during its fixing by an operator while taking into account the manufacturing tolerances of the parts. Brief description of the figures

[0034] Other characteristics and advantages of the invention will appear during the reading of the detailed description which follows for the understanding of which one will refer to the appended figures.

[0035] This is a rear view which schematically represents a vehicle chassis fitted with wheels and on which a traction battery has been mounted.

[0036] This is a perspective view of a traction battery capable of being mounted on the vehicle, the battery being capable of being equipped with a cover produced according to the teachings of the invention.

[0037] This is a sectional view according to section plane 3-3 of which represents valves which equip a rear vertical wall of the traction battery.

[0038] This is a schematic side view which represents a traction battery produced according to the teachings of the invention mounted on the vehicle of the.

[0039] This is a longitudinal vertical sectional view in perspective which represents the rear vertical wall of the battery equipped with its valve protection cover.

[0040] This is a sectional view along section plane 6-6 of which represents an internal face of the hood produced according to the teachings of the invention and the valves which it protects.

[0041] This is a front view of the rear vertical wall of the traction battery equipped with the hood according to the teachings of the invention.

[0042] This is a sectional view along section plane 8-8 of which represents a means of fixing by screwing the cover onto the rear vertical wall of the traction battery. Detailed description of the invention

[0043] In the remainder of the description, elements having an identical structure or similar functions will be designated by the same reference.

[0044] In the following description, the following guidelines will be adopted, without limitation:

[0045] - longitudinal “L” directed in the direction of movement of the vehicle and oriented from the front to the rear of the vehicle;

[0046] - vertical “V” directed orthogonally to the road on which the vehicle is traveling and oriented from below, near the road, upwards;

[0047] - transverse “T” directed orthogonally to the longitudinal and vertical directions, and oriented from left to right.

[0048] A motor vehicle 10 is schematically shown from behind. This is a vehicle 10 comprising at least one electric traction motor (not shown) such as an electric vehicle or a hybrid vehicle also comprising a thermal engine.

[0049] The vehicle 10 comprises a chassis 12 connected to four wheels 14, two of which are visible, by means of an articulated suspension device 16.

[0050] The chassis 12 extends generally horizontally. It comprises a crossmember 18,. A vehicle traction battery 20 for powering the electric traction motor which is intended to be fixed under the crossmember 18 by means of protrusions 82. The protrusions 83 of the traction battery 20 are fixed directly to the chassis.

[0051] As shown in the, the traction battery 20 comprises a container 22. The container 22 here has the overall shape of a parallelepiped, sealingly enclosing an interior space 24 containing electric accumulators (not shown). This interior space 24 is delimited by a horizontal upper wall 26, a horizontal lower wall 28, a rear vertical wall 30, a front vertical wall 32, a left lateral vertical wall 34 and a right lateral vertical wall 36.

[0052] The walls of the tank 22 are, for example, made of a metallic material, such as aluminum.

[0053] As explained in the preamble, the traction battery 20 comprises at least one valve 38, 40 which is arranged in an associated orifice 42, 44 which passes through one of the vertical walls of the tank 22, as illustrated in the. This at least one valve 38, 40 makes it possible to communicate the interior space 24 of the tank 22 with the exterior.

[0054] By way of non-limiting example, the at least one valve 38, 40 is here arranged in the rear vertical wall 30 of the tank 22.

[0055] By way of non-limiting example, the tank 22 here comprises two valves 38, 40 which are arranged close to each other in the same vertical wall 30. The two valves 38, 40 are here arranged substantially at the same height on the rear vertical wall 30.

[0056] Each valve 38, 40 comprises a flap 46 which is mounted to move between a closed position in which it bears against a seat 47 of the associated vertical wall 30, as shown in solid lines in the, and an open position in which it is lifted from its seat outwards to open the associated orifice 42, 44, as shown in broken lines in the. An annular sealing gasket 48 is interposed between the seat 47 and the flap 46 to allow the sealed closure of the associated orifice 42, 44 when the flap 46 occupies its closed position. This is a sealing gasket 48 made of elastomeric material.

[0057] As shown in , the rear wall 30 of the tray 22 of the traction battery 20 is generally arranged at a distance from the neighboring components 50 of the vehicle, so that a free gap 52 is reserved between the neighboring component 50 and the rear wall 30. This free gap 52 opens towards the bottom of the vehicle. As a result, when the vehicle is cleaned by means of a high-pressure cleaning device, the rear wall 30, and more particularly the valves 38, 40, are exposed to the high-pressure water jet.

[0058] It has been found that when a high-pressure water jet is directed towards the seal 48 of the valves 38, 40 in a direction “F” inclined relative to a direction orthogonal to the associated vertical wall 30, here inclined relative to a longitudinal direction, the water jet elastically deforms the sealing seal 48. The seal 48 can then no longer fulfill its sealing function, which allows water to penetrate into the interior space 24 of the tank 22.

[0059] To solve this problem, the invention proposes to arrange a protective cover 54 which is fixed against an external face 56 of said vertical wall 30 of the tank 22 by covering the at least one valve 38, 40.

[0060] The cover 54 is fixed only to the tray 22. In addition, the cover 54 is in contact only with the tray 22. Therefore, it is possible to mount the cover 54 on the tray 22 before the traction battery 20, thus equipped with its cover 54, is mounted under the chassis 12.

[0061] More particularly, the cover 54 is fixed only to the rear vertical wall 30 of the tank 22.

[0062] The cover 54 here simultaneously covers the two valves 38, 40.

[0063] In a variant of the invention not shown, each valve 38, 40 is protected by such an individual cover.

[0064] The cover 54 extends in a main plane “P” generally parallel to that of the vertical wall 30 in which each valve 38, 40 is arranged. The cover 54 has a concave shape so as to delimit a cavity 58 surrounding the valves 38, 40 by cooperation with the associated vertical wall 30, as illustrated in. This cavity 58 notably allows the valves 38, 40 to open without interference. It is also sufficient to allow the exchange of fluid between the interior space 24 of the tank 22 and the exterior via the valves 38, 40.

[0065] The cover 54 here comprises a main plate 60 which extends in the plane “P” generally parallel to the rear vertical wall 30. This plate 60 is arranged longitudinally at a distance from the valves 38, 40 to allow the cavity 58 to be delimited.

[0066] The cover 54 comprises at least one lower rim 62, a free end transverse edge 63 of which is in contact with the external face 56 of the vertical wall 30 of the tank 22 below the valves 38, 40. The lower rim 62 here extends along a generally horizontal plane, orthogonal to the vertical wall 30. The rim 62 extends for example from a generally horizontal lower edge of the main plate 60 in the direction of the rear vertical wall 30.

[0067] The lower rim 62 is intended to intercept a jet of water directed directly towards the at least one valve 38, 40 from below the vehicle.

[0068] The cover 54 is not fixed in a sealed manner to the rear vertical wall 30 of the tank 22 because it is necessary to allow the exchange of fluids between the interior space 24 of the tank 22 and the outside atmosphere. As a result, water is still likely to penetrate inside the cavity 58 delimited by the cover 54 and the rear vertical wall 30. To allow the water to drain by gravity to the outside of the cavity 58, the lower rim 62 has water drainage orifices 65, as is particularly visible in the.

[0069] The evacuation orifices 65 are here formed by notches made in the free end edge of the lower rim 62.

[0070] The hood 54 may also have an upper rim 64 and side rims 66. However, these rims are only present in areas where a high-pressure water jet emitted from underneath the vehicle can reach the valves 38, 40 from above or the sides of the hood 54 arranged on the tank 22.

[0071] Although the presence of the lower rim 62 and the main plate 60 of the cover 54 makes it possible to drastically reduce the risk of reaching a valve 38, 40 directly with a high-pressure water jet, there remains a risk of causing the water jet to penetrate directly into the cavity 58 by passing through the water discharge orifices 65.

[0072] To complete the protection of the valves 38, 40, the cover 54 comprises an internal face 68 equipped with at least one deflector 70 which is interposed between the discharge orifices 65 and the at least one valve 38, 40. The deflector 70 is intended to intercept any jet of water passing through a discharge orifice 65 and directed towards the at least one valve 38, 40. For this purpose, the at least one deflector 70 is interposed between the discharge orifices 65 and each of the two valves 38, 40.

[0073] Here the hood 54 comprises a single deflector 70 which simultaneously protects the two valves 38, 40. The deflector 70 is interposed between the discharge orifices 65 and each of the two valves 38, 40.

[0074] More particularly, the deflector 70 extends here from an internal face 68 of the main plate 60 of the cover 54 towards the rear vertical wall 30. A free end transverse edge 71 of the deflector 70 is substantially in contact with the rear vertical wall 30.

[0075] The deflector 70 here extends parallel to and above the lower rim 62.

[0076] The cover 54 is here made of a rigid plastic material.

[0077] The cover 54 is preferably made in a single piece. The cover 54 is for example made in a single piece by molding.

[0078] The deflector 70 is here formed by a rib which extends from the internal face 68 of the cover 54 towards the rear vertical wall 30 of the tank 22.

[0079] To prevent the water jet from entering through non-watertight gaps between the free edge 63 of the lower rim 62 of the cover 54 and the rear vertical wall 30, two transverse protective strips 72 are welded against the rear vertical wall 30 below each valve 38, 40 and below at a vertical distance from the cover 54. The two protective strips 72 are spaced transversely from each other. The transverse gap between the two strips 72 extends substantially in line with the discharge orifices 65, as shown in Figures 6 and 7.

[0080] The cover 54 can be fixed to the rear vertical wall 30 in any known manner, for example by screwing, by gluing, by elastic fitting, etc.

[0081] In the embodiment shown in , the cover 54 is fixed to the rear vertical wall 30 by screwing.

[0082] The vertical wall 30 is formed by an outer casing 30A comprising the outer face 58 and an inner partition 30B parallel to the outer casing 30A. The inner partition 30B and the outer casing 30A are separated by an air gap 30C. Two fixed nuts 74 are fixed in an associated hole of the outer casing 30A. A threaded rod 76 of a stud is screwed into each fixed nut 74 by penetrating the air gap 30C but without passing through the inner partition 30B. The cover 54 has holes 78 for the passage of each threaded rod 76. The passage holes 78 are here arranged vertically at the same level, between the two valves 38, 40. A free nut 80 is then screwed to each threaded rod 76 to tighten the cover 54 between the fixed nuts 74 and the free nuts 80. To facilitate the insertion of the threaded rods 76 into the passage holes 78, they are surrounded, on the internal face 68 of the cover 54, by a chamfer.

[0083] As shown in , the valves 38, 40 are generally arranged between two protrusions 82 which extend longitudinally projecting from the external face 58 of the rear vertical wall 30. Each protrusion 82 here has the shape of a parallelepiped. Each protrusion 82 thus has a longitudinal vertical support face 84 which is turned towards the other protrusion 82. The two support faces 84 are thus transversely opposite each other on either side of the cover 54. In addition, each protrusion has a lower horizontal face 86.

[0084] To facilitate the mounting of the cover 54 on the rear vertical wall 30 of the tank 22, the cover 54 comprises at one of its transverse ends an elastically flexible tab 88 which is intended to be elastically clamped against a bearing face 84, while an opposite rigid transverse end 90 of the cover 54 bears against the opposite bearing face 84. The clamping of the cover 54 between the two bearing faces 84 by elastic deformation of the elastic tab 88 makes it possible to hold the cover 54 in position while an operator fixes the cover 54 to the rear vertical wall 30. In addition, the elastic tab 88 allows automatic centering of the cover 54 between the two protrusions 82 in a transverse direction.

[0085] To facilitate the positioning of the cover 54 vertically, it comprises two positioning faces 92 which are intended to abut vertically upwards against the lower face 86 of each protuberance 82.

[0086] During its assembly, the cover 54 is positioned between the two protrusions 82, at a distance from the rear vertical wall 30. Then, the cover 54 is positioned so that the positioning faces 92 are in abutment against the lower faces 86 of the protrusions 82. The cover 54 is then moved longitudinally forward so as to cause the threaded rods 76 to penetrate into the associated holes 78 of the cover 54. The holes 78 have an oblong shape elongated in the transverse direction to allow the elastic tab 88 to transversely center the cover 54 between the two protrusions 82. The cover 54 is then fixed by screwing the free nuts 80.

[0087] The cover 54 can advantageously be mounted or removed from the vertical wall 30 of the tank 22 when the traction battery 20 is mounted on the chassis 12, to facilitate the work of the operator.

[0088] The cover 54 thus positioned advantageously makes it possible to prevent a high-pressure water jet from directly reaching the valves 38, 40. This thus makes it possible to avoid accidental damage to the traction battery 20 when cleaning the vehicle.

Claims

Motor vehicle traction battery (20) comprising:- a container (22) containing electric accumulators;- at least one valve (38, 40) which is arranged in a vertical wall (30) of the container (22);- a protective cover (54) which is fixed against an external face (58) of said vertical wall (30) by covering the at least one valve (38, 40);characterized in that the cover (54) comprises at least one lower rim (62) of which a free end edge (63) is in contact with the external face (58) of the vertical wall (30) and which is intended to intercept a jet of water directed towards the at least one valve (38, 40), the lower rim (62) comprising water discharge orifices (65). Traction battery (20) according to the preceding claim, characterized in that the cover (54) comprises an internal face (68) equipped with at least one deflector (70) which is interposed between the discharge orifices (65) and the at least one valve (38, 40), the deflector (70) being intended to intercept a jet of water passing through the discharge orifices (65) and directed towards the at least one valve (38, 40). Traction battery (20) according to the preceding claim, characterized in that the deflector (70) is formed by a rib which extends from the internal face (68) of the cover (54) in the direction of the vertical wall (30) of the tank (22). Traction battery (20) according to any one of the preceding claims, characterized in that said vertical wall (30) comprises two valves (38, 40), said cover (54) simultaneously covering the two valves (38, 40). Traction battery (20) according to the preceding claim taken in combination with any one of claims 2 or 3, characterized in that the at least one deflector (70) is interposed between the discharge orifices (65) and each of the two valves (38, 40). Traction battery (20) according to any one of the preceding claims, characterized in that the cover (54) is made of a plastic material. Traction battery (20) according to the preceding claim, characterized in that the cover (54) is made in a single piece by molding. Traction battery (20) according to any one of the preceding claims, characterized in that the vertical wall (30) is made of an external envelope (30A) comprising the external face (58) and an internal partition (30B) separated by an air gap (30C), the cover (54) being fixed to the vertical wall (30) by means of a nut (74) fixed in the external envelope (30A) and a threaded rod (76) which penetrates into the air gap (30C) without passing through the internal partition (30B). Traction battery (20) according to any one of the preceding claims, characterized in that the vertical wall (30) of the container (22) is equipped with two vertical bearing faces (84) facing each other and projecting orthogonally relative to the vertical wall (30) between which the cover (54) is received, the cover (54) comprising a tab (88) with an elastically flexible free end making it possible to hold the cover (54) between the two bearing faces (84) by clamping.

Images