MOTOR VEHICLE BATTERY WITH A CASING DESIGNED TO STOP A FIRE

Abstract

One aspect of the invention relates to a vehicle battery 1 comprising: A series of cell modules 5; A casing 6 surrounding the modules 5; An inlet 7 for extinguishing agent formed in a wall 8 of the casing 6; A discharge channel 10 for the extinguishing agent disposed in the casing 6; A perforating piston 11 disposed in the discharge channel 10, the piston 11 having a discharge conduit 12 for the extinguishing agent; A closing flap 16 for the inlet of the discharge conduit 12; The piston 11 being movable in the discharge channel 10 between a rest position and a perforation position in a wall 18 of the casing 6, and the flap 16 being integral with a float 21 and movable between a closed position P3 and an open position P4 of the discharge conduit 12. Figure 1

Description

Title of the invention: MOTOR VEHICLE BATTERY COMPRISING A CASING ARRANGED TO STOP A FIRE

[0001] The invention relates, in general, to the technical field of traction batteries for electric or hybrid motor vehicles.

[0002] This type of battery is used to supply energy to at least one electric traction motor that the vehicle includes and is arranged to be recharged by an electrical terminal external to the vehicle and / or by the electric motor in generator operation.

[0003] Motor vehicle batteries are generally formed from a set of modules in which each module comprises a set of electrical energy storage cells. These storage cells may undergo degassing during use. The gases thus produced must then be evacuated in a simple manner. For this, all of the battery modules are contained in a protective casing which includes a vent for this purpose. Such a vent is for example disclosed by document WO-A1-202317223.

[0004] On the other hand, it is necessary to provide an admission of extinguishing product to the battery so that, in the event of an accident, the emergency services can, using a liquid extinguishing product, cool the modules, and therefore the cells of the battery in order to avoid a “battery” fire starting.

[0005] For example, document US-A1-2022 / 0355138 discloses a circuit for supplying a fire extinguishing product to a motor vehicle battery. In order to prevent the unintentional penetration of liquid into the battery, the supply circuit comprises an active locking mechanism which can be unlocked and locked by means of an associated unlocking unit. However, the document does not disclose an optimal solution offering the possibility of completely flooding the battery modules.

[0006] The aim of the invention is in particular to propose a motor vehicle battery whose protective casing is arranged to effectively stop any possible fire starting in the battery.

[0007] In this context, the invention thus relates, in its broadest sense, to a motor vehicle battery comprising: • A series of electrical energy storage cell modules; • A protective casing surrounding the modules; • An extinguishing product intake opening provided in a first wall of the protective casing; • A channel for discharging the extinguishing product located in the casing; • A perforating piston arranged in the discharge channel, the perforating piston comprising a conduit for discharging the extinguishing product; • A hatch to close the entrance to the exhaust duct; • the perforating piston being movable in the discharge channel between a rest position and a position for perforating a second wall of the protective casing in which the discharge conduit opens outside the protective casing, said perforating piston being movable in response to an overpressure exerted by the extinguishing product on the hatch, the hatch being secured to a float and movable between a closed position and an open position of the discharge conduit in response to an increase in the volume of extinguishing product present in the protective casing.

[0008] Thanks to the float associated with the closing hatch of the discharge conduit of the perforating piston, it is ensured that the battery modules are completely submerged in the extinguishing product before allowing an evacuation of said extinguishing product to the outside. In other words, this arrangement allows, in a first step, immersion of the storage cells, then in a second step, an evacuation of the extinguishing product to evacuate the calories resulting from heating of the storage cells.

[0009] In addition to the characteristics which have just been mentioned in the preceding paragraph, the battery according to the invention may have one or more additional characteristics among the following, considered individually or according to all technically possible combinations.

[0010] According to a non-limiting aspect of the invention, the inlet opening is arranged to allow the extinguishing product to enter the protective casing when a pressure exerted by the extinguishing product on the inlet opening reaches a predetermined pressure threshold.

[0011] According to a non-limiting aspect of the invention, the discharge conduit that the perforating piston comprises is formed by a longitudinal orifice opening out at both ends of said perforating piston.

[0012] According to a non-limiting aspect of the invention, the discharge conduit that the perforating piston comprises is formed by a blind longitudinal orifice opening out on the side of the closure hatch and an orifice perpendicular to the blind longitudinal orifice opening out into the blind longitudinal orifice.

[0013] According to a non-limiting aspect of the invention, the evacuation conduit that the perforating piston comprises is formed by a blind longitudinal orifice opening out on the side of the shutter hatch and an orifice perpendicular to said blind longitudinal orifice crossing the width of the perforating piston and the blind longitudinal orifice.

[0014] According to a non-limiting aspect of the invention, the battery comprises a stop for stopping the movement of the perforating piston in the position for perforating the second wall of the protective casing.

[0015] According to a non-limiting aspect of the invention, the battery has a voltage of at least 48V.

[0016] Another aspect of the invention relates to a motor vehicle comprising a battery according to any one of the aforementioned aspects of the invention.

[0017] According to a non-limiting aspect of the invention, the protective casing is secured to a first side member and to a second side member of the motor vehicle, • The first spar comprising an opening provided opposite the intake opening, the first spar forming a conduit for conveying the extinguishing product to the intake opening, • The second spar comprising an opening provided opposite the perforating piston, the second spar forming a discharge pipe for the extinguishing product coming from the discharge pipe of the perforating piston.

[0018] According to a non-limiting aspect of the invention, the extinguishing product discharge channel in which the perforating piston is arranged is arranged along a third wall of the protective casing, the third wall being arranged opposite the rear of the motor vehicle.

[0019] According to a non-limiting aspect of the invention, the vehicle is hybrid or electric.

[0020] The invention and its various applications will be better understood upon reading the description which follows and the examination of the figures which accompany it.

[0021] [Fig-1] illustrates, in a schematic manner, a non-limiting example of an embodiment of a motor vehicle battery according to the invention.

[0022] [Fig.2] illustrates, schematically, a side view of the battery illustrated in [Fig.l] in which an extinguishing product is introduced into a first side member of the vehicle.

[0023] [Fig.3] illustrates, schematically, a side view of the battery illustrated in [Fig.l] in which the extinguishing product is introduced into a battery protection casing.

[0024] [Fig.4] illustrates, schematically, a side view of the battery illustrated in [Fig.l] in which a shutter hatch which the battery contains is open.

[0025] [Fig.5] illustrates, schematically, a side view of the battery illustrated in [Fig.l] in which the extinguishing product is introduced into a second side member of the vehicle.

[0026] [Fig.6] illustrates an example of an embodiment of a perforating piston which comprises the battery according to the invention.

[0027] [Fig.7] illustrates another example of embodiment of a perforating piston which comprises the battery according to the invention.

[0028] The figures are presented for information purposes only and in no way limit the invention.

[0029] Unless otherwise specified, the same element appearing in different figures has a single reference.

[0030] More particularly, figures 1 to 5 illustrate an exemplary embodiment of a motor vehicle battery 1 according to the invention secured to a first side member 2 and a second side member 3 of a motor vehicle 4.

[0031] This vehicle battery 1 may be, for example, a 48V or 400V type battery.

[0032] More particularly, [Fig.l] illustrates a top view of the battery 1. The battery 1 comprises a series of modules 5 of cells for storing electrical energy and a protective casing 6 surrounding the modules 5. According to this embodiment, the protective casing 6 forms a rectangle.

[0033] According to a different embodiment not illustrated, the protective casing 6 forms a square.

[0034] An inlet opening 7 for extinguishing product is provided in a first wall 8 of the protective casing 6. The first side member 2 has an opening 9 provided opposite the inlet opening 7. It should be noted that the first side member 2 forms a conduit for conveying the extinguishing product to the inlet opening 7.

[0035] Furthermore, a discharge channel 10 for the extinguishing product is provided in the protective casing 6. A perforating piston 11 is arranged in the discharge channel 10.

[0036] As can be seen in the side views 1b to 1c, the perforating piston 11 comprises a discharge conduit 12 for the extinguishing product injected into the protective casing 6 via the inlet opening 7.

[0037] In this non-limiting embodiment, the discharge conduit 12 that the perforating piston 11 comprises is formed by a blind longitudinal orifice 13 and an orifice 14 perpendicular to the blind longitudinal orifice 13. The perpendicular orifice 14 passes through the width of the perforating piston 11 and the blind longitudinal orifice 13.

[0038] In a different embodiment illustrated in [Fig.6], the perpendicular orifice 14 opens into the blind longitudinal orifice 13 but does not cross the width of the perforating piston 11.

[0039] In a still different embodiment illustrated in [Fig.7], the discharge conduit 12 which the perforating piston 11 comprises is formed by a longitudinal orifice 15 opening out at both ends of the perforating piston 11.

[0040] The battery 1 also includes a hatch 16 for closing the inlet of the evacuation duct 12.

[0041] As illustrated in [Fig.2], during an accident, the emergency services inject an extinguishing product in liquid form into the first spar 2. The injection product passes through the opening 9 of the first spar 2 to go towards the intake opening 7 which the first wall 8 of the protective casing 6 comprises. The intake opening 7 is arranged to allow the extinguishing product to enter the protective casing 6 when a pressure exerted by said extinguishing product on the intake opening 7 reaches a predetermined pressure threshold.

[0042] To this end, in a non-limiting embodiment, this intake opening 7 may for example comprise a membrane 17 arranged to perforate and allow the extinguishing product to pass when a pressure exerted by the extinguishing product on the membrane 17 reaches a predetermined threshold pressure.

[0043] As illustrated in [Fig. 3], when the membrane 17 ruptures, the extinguishing product penetrates into the protective casing 6 and exerts an overpressure on the closing hatch 16 causing the perforating piston 11 to move in the discharge channel 10 from a rest position PI to a perforation position P2 of a second wall 18 of the protective casing 6.

[0044] The movement of the perforating piston 11 is stopped in the perforation position P2 by a stop 19 for stopping the movement of the perforating piston 11 which is included in the protective casing 6.

[0045] It should be noted that the second spar 3 has an opening 20 arranged opposite the perforating piston 11. The discharge conduit 12 of the perforating piston 11 opens into the second spar 3 when the perforating piston 11 is in the perforation position P2 of the second wall 18 of the protective casing 6.

[0046] As illustrated in [Fig. 4], the closure hatch 16 is secured to a float 21 so that when the volume of extinguishing product present in the protective casing 6 increases, the closure hatch 16 moves from a closure position P3 to an opening position P4 of the evacuation conduit 12 which the perforating piston 11 comprises.

[0047] As illustrated in [Fig.5], as soon as the closure hatch 16 is in the open position P4, the extinguishing product flows into the evacuation duct 12 to go towards the second side member 3.

[0048] The second spar 3 thus forms a duct for discharging the extinguishing product coming from the discharge duct 12 of the perforating piston 11.

[0049] According to this embodiment, the discharge channel 10 of the extinguishing product in which the perforating piston 11 is arranged is arranged along a third wall 22 of the protective casing 6, the third wall 22 being arranged opposite the rear of the vehicle 4. The rear of vehicle 4 is understood as the side where the trunk 23 of vehicle 4 is located.

Claims

Claims

1. Battery (1) of a motor vehicle (4) comprising: - A series of modules (5) of cells for storing electrical energy; - A protective casing (6) surrounding said modules (5); - An inlet opening (7) for extinguishing product formed in a first wall (8) of said protective casing (6); - A discharge channel (10) for said extinguishing product arranged in said protective casing (6); - Said battery (1) being characterized in that it comprises: - A perforating piston (11) arranged in said discharge channel (10), said perforating piston (11) comprising a discharge conduit (12) for said extinguishing product; - A hatch (16) for closing the inlet of said discharge conduit (12);- said perforating piston (11) being movable in said discharge channel (10) between a rest position (PI) and a perforation position (P2) of a second wall (18) of said protective casing (6) in which said discharge conduit (12) opens outside said protective casing (6), said perforating piston (11) being movable in response to an overpressure exerted by said extinguishing product on said closure hatch (16), said closure hatch (16) being integral with a float (21) and movable between a closure position (P3) and an opening position (P4) of said discharge conduit (12) in response to an increase in the volume of extinguishing product present in said protective casing (6).;

2. Battery (1) according to the preceding claim, characterized in that the inlet opening (7) is arranged to allow the extinguishing product to enter the protective casing (6) when a pressure exerted by said extinguishing product on the inlet opening (7) reaches a predetermined pressure threshold.

3. Battery (1) according to any one of the preceding claims, ca- characterized in that the discharge duct (12) which the perforating piston (11) comprises is formed by a longitudinal orifice (15) opening at both ends of said perforating piston (11).

4. Battery (1) according to any one of claims 1 or 2, characterized in that the evacuation duct (12) which the perforating piston (11) comprises is formed by a blind longitudinal orifice (13) opening on the side of the closure hatch (16) and an orifice perpendicular (14) to said blind longitudinal orifice (13) opening into said blind longitudinal orifice (13).

5. Battery (1) according to any one of claims 1 or 2, characterized in that the evacuation duct (12) which the perforating piston (11) comprises is formed by a blind longitudinal orifice (13) opening on the side of the closure hatch (16) and an orifice perpendicular (14) to said blind longitudinal orifice (13) crossing the width of said perforating piston (11) and said blind longitudinal orifice (13).

6. Battery (1) according to any one of the preceding claims, characterized in that it comprises a stop (19) for moving the perforating piston (11) into the perforation position (P2) of the second wall (18) of the protective casing (6).

7. Battery (1) according to any one of the preceding claims, characterized in that it has a voltage of at least 48V.

8. Motor vehicle (4) comprising a battery (1) according to any one of the preceding claims.

9. Motor vehicle (4) according to the preceding claim, characterized in that the protective casing (6) is secured to a first side member (2) and to a second side member (3) of said motor vehicle (4), - Said first side member (2) comprising an opening (9) arranged opposite the intake opening (7), said first side member (2) forming a conduit for conveying the extinguishing product to said intake opening (7), - Said second side member (3) comprising an opening (20) arranged opposite the perforating piston (11), said second side member (3) forming a conduit for discharging the extinguishing product from the discharge conduit (12) of the perforating piston (11).

10. Motor vehicle (4) according to any one of claims 8 or 9, characterized in that the discharge channel (10) of the extinguishing product in which the perforating piston (11) is arranged is arranged along a third wall (22) of the protective casing (6), said third wall (22) being arranged opposite the rear of the motor vehicle (4).