BURST MEMBRANE AND SAFETY VALVE SYSTEM CONTAINING A BURST MEMBRANE

Abstract

The invention relates to a diaphragm for a breathing valve for an electrochemical energy storage device, comprising: - at least a first zone (2) allowing breathing in both directions through the diaphragm, at least for a pressure below a first threshold (P1); - at least a second zone (4), different from the first zone (2), designed to burst for a pressure (P2) above the first threshold. Figure 1A for the abstract

Description

Title of the invention: BURST MEMBRANE AND SAFETY VALVE SYSTEM CONTAINING A BURST MEMBRANE TECHNICAL FIELD AND PREVIOUS ART

[0001] The invention relates to the field of energy storage means, in particular of the type used in vehicles, for example of the type for moving materials and / or people, these storage means implementing electrochemical type solutions.

[0002] The invention relates in particular to an application connected with batteries, especially lithium-ion batteries, which consist of a sealed casing comprising a set of individual cells and, most often, electronic and power components for their interconnection and control. Battery technologies, now indispensable, are experiencing increasing energy density and evolving architectures. In the event of a major exothermic phenomenon occurring in the battery, for example, thermal runaway or even a fire, the battery will release a large amount of energy and gas, necessitating the opening or rupture of a dedicated system such as, for example, a venting valve.

[0003] Each cell in the battery will potentially experience a temperature increase during the thermal runaway of one or more cells. This will lead to the complete propagation of the fire inside the pack or, more generally, the casing.

[0004] Once established within the battery compartment, the fire risks spreading to the surrounding battery environment and then to the entire system equipped with the battery, for example, a vehicle. It is possible, through the use of ventilation systems, to limit the heat spread and therefore the intensity of the battery fire.

[0005] Today we know of irreversible systems, but which are not very efficient at low pressure; the opening of this type of system is generally done at about 200 mbar.

[0006] One advantage of this type of system lies in the passage area, which is generally larger than that of other, so-called reversible, systems. The larger passage area allows for higher flow rates.

[0007] But a situation may also occur in which the pressure resulting, for example, from internal overheating of the battery, does not require an irreversible opening.

[0008] No system is known that has the advantage of a high flow rate in the event of a major exothermic phenomenon occurring in a battery, while also allowing evacuation with a reversible system in the event of a less serious event.

[0009] An objective of the invention is to have a membrane, which can for example be used in a valve, for example a breathing valve for a device for storing energy in electrochemical form, this membrane combining various functions, including an evacuation function but also a breathing function, which makes it possible to balance the pressure between the environment and the inside of a volume, for example containing a battery.

[0010] Another objective of the invention is to propose a solution, for example a valve, of hybrid type.

[0011] Yet another objective of the invention is to provide a solution, for example a valve, with a certain opening precision: this opening precision allows for a clearer definition, particularly through simulation, of the thermal runaway transfer dynamics. It also makes it possible to use several valves that will open at the same pressure level, which is impossible with solutions comprising only a "burst valve" within the battery in the event of an incident not requiring irreversible opening.

[0012] Yet another objective of the invention is to propose a solution, for example a valve, having different functions, including opening and / or bursting.

[0013] Yet another need is for a valve combining various functions, such as an evacuation and / or bursting function and / or a breathing function: different valves are used to perform these different functions, but this requires different assemblies, resulting in a complex system. It would be preferable to be able to implement a single assembly.

[0014] Yet another need is for a new valve structure capable of combining various functions in different areas of the valve. Description of the invention

[0015] The invention relates first to a membrane, for example or in particular for a breathing valve for an electrochemical energy storage device, this membrane comprising:

[0016] - at least one zone allowing respiration, in both directions through the membrane, at least for a pressure (or a pressure difference between the 2 sides of the membrane) lower than a 1st threshold (Pi);

[0017] - at least a second zone, different from the first zone, intended to burst for a pressure (or a pressure difference between the 2 sides of the membrane) above the 1st threshold (PO.

[0018] According to various realizations:

[0019] - the membrane is flat;

[0020] - and / or the 2 zones are juxtaposed;

[0021] - and / or one of the 2 zones surrounds the other zone;

[0022] - and / or each of the zones has an outer contour:

[0023] * circular or elongated or oval-shaped, for example an area being in the shape of a ring, and surrounding the other area, which is central, in the shape of a disc;

[0024] * or square or rectangular or polygonal in shape, for example again an area surrounding the other area, which is central;

[0025] - and / or the first zone and the second zone are fixed to each other, for example by welding;

[0026] - and / or the first zone and the second zone are fixed or assembled on or with the same support, for example a film or an adhesive layer;

[0027] - and / or the 2nd zone forms a thin layer or a multilayer and / or is in a plastic or metallic material, for example in a material such as polypropylene or polyethylene, or in e-PTFE; alternatively, the 2nd zone may be in natural or synthetic fiber(s), or in hemp, or in coconut;

[0028] - and / or the first zone is made of a porous material, for example e-PTFE or silicone perforated or made of fibrous material.

[0029] Alternatively, the first zone can be made of felt or a woven material.

[0030] The constituent material of all or part of the membrane may comprise at least in part a hydrophobic and / or waterproof and / or oleophobic property and / or be provided with a hydrophobic and / or oleophobic coating and / or the membrane comprising at least one waterproof part.

[0031] According to an exemplary embodiment, the first zone of a membrane according to the invention has a flow rate of between 0.2 and 3.5 l / min / cm2 for example when the pressure difference between the inside and outside of the storage volume is 20 mbar.

[0032] The invention also relates to a valve for an electrochemical energy storage device, this device comprising a casing, this valve itself comprising:

[0033] - a valve body;

[0034] - at least one membrane, which may be, according to the invention, a membrane such that described above and in the remainder of this application, capable at least of bursting for a pressure difference between its 2 sides greater than a threshold (Pi) and means forming at least a 1st support of said 1st membrane;

[0035] - means maintaining the valve in a closed state for a pressure difference between the 2 sides of the lower membrane at (P2), Pi > P2 and allowing the valve to open when this pressure difference is between (PO and (P2).

[0036] The first membrane can be held against the support using retaining means, for example a grid and / or a ring.

[0037] Preferably the first membrane is waterproof.

[0038] According to one embodiment, the first membrane is a membrane according to the invention, further allowing at least one respiration by circulation of fluid through this membrane.

[0039] In a valve according to the invention, the support means can be arranged at one end of a piston, which passes through the valve body.

[0040] The means for maintaining the valve in a closed state keep it closed for a pressure difference less than (P2) and allow the valve to open when this pressure difference is between (P1) and (P2); for example, these means comprise at least one spring, for example a straight or spiral spring, each bearing against a fixed part of the valve body and a movable part, attached to the support, which includes, for example, a stop. The properties of this spring and its greater or lesser compression between the supports will determine the opening pressure of the valve.

[0041] The invention also relates to an energy storage enclosure in electrochemical form, for example of battery type, comprising an envelope containing one or more energy storage elements, this envelope being equipped with at least one valve according to the invention.

[0042] The invention also relates to a vehicle, comprising a passenger compartment and / or a storage area, an engine, and at least one energy storage enclosure according to the invention.

[0043] The invention also relates to a method of operating a valve in an electrochemical energy storage vessel according to the invention, a method in which:

[0044] a) - the valve is maintained in a closed state for a pressure difference less than (P2);

[0045] b) - the valve is in an open state for a pressure difference between (PO and (P2), P, > P2;

[0046] c) - the membrane bursts for a pressure difference greater than (P2).

[0047] For example, the membrane has at least a breathing part and there is fluid exchange between the inside and outside of the enclosure through the membrane at least during step a). Brief description of the drawings

[0048] [Fig.1A] - [Fig.1B] - [Fig.1C] - [Fig.1D] represents various aspects of examples of realization of a membrane according to the invention;

[0049] [Fig.2A] - [Fig.2B] - [Fig.2C] - [Fig.2D] - [Fig.2E] represent various aspects of an example of an embodiment of a breathing and bursting valve which may include a membrane according to the invention;

[0050] [Fig.3A] - [Fig.3B] - [Fig.3C] represent various aspects of another example of an embodiment of a valve equipped with a membrane according to the invention, comprising a breathing zone and a bursting zone;

[0051] [Fig.4A] - [Fig.4B] - [Fig.4C] represent various aspects of another example of an embodiment of a valve equipped with a bursting membrane according to the invention;

[0052] Fig. 5 represents an enclosure of an energy storage device comprising a valve according to the invention and a discharge valve.

[0053] Figs [6A] - [Fig.6B] - [Fig.6C] - [Fig.6D] represent various vehicles or machines, automobile, airplane, boat, locomotive, equipped with an energy storage device comprising a valve according to the invention as well as a discharge valve.

[0054] DETAILED DESCRIPTION OF SPECIFIC EMBODIMENTS

[0055] Fig. 1A represents a first example of the realization of a flat membrane 1 according to the invention.

[0056] It comprises:

[0057] - a first zone 2, allowing respiration, in both directions through the membrane, perpendicular or substantially perpendicular to the plane defined by it, for a pressure difference between the two sides of the membrane less than a 1st threshold (Pi);

[0058] - a second zone 4, called the bursting zone, designed to burst under a pressure difference between the two sides of the upper membrane at the 1st pressure threshold Pb the two zones being juxtaposed and fixed to each other.

[0059] In [Fig. 1A], the membrane comprises a first central zone 2, disc-shaped, surrounded by the second zone 4, ring-shaped. Alternatively (not shown), the distribution of the two zones may be the reverse of that in [Fig. 1A], the membrane comprising a first (respiration) ring-shaped zone surrounding the second bursting zone, which is central and disc-shaped.

[0060] Alternatively ([Fig. 1B]) these zones can be elongated or oval in shape, one of them (here zone 2a allowing respiration) being positioned in the center and surrounded by the other zone (here zone 4a bursting). Here again, the distribution of the two zones can be reversed.

[0061] Alternatively ([Fig. IC]), each of the two zones can be square or rectangular or more generally polygonal in shape:

[0062] - one of the two zones 2b (breathing) being surrounded by the other 4b (burst): this is the case of [Fig.lC], the 2 zones can be reversed;

[0063] - one of the two zones 2c (respiration) being juxtaposed with the other 4c (burst), Here again the 2 zones can be reversed; this is the case of [Fig.lD].

[0064] Other shapes and / or distributions of these zones can be achieved.

[0065] The first zone 2, 2a, 2b, 2c of the examples described above allows for respiration; it is, for example, made of a porous material, the air porosity being defined by the airflow in L / min / kPa. The flow rate of a porous membrane is defined at a certain pressure level, because it is the pressure difference between one side and the other of the membrane that creates a mass exchange over a certain surface area; thus, membranes generally used, for example, for battery applications can have a flow rate of 0.2 to 3.5 L / min / cm², for example, when the pressure difference between the inside and outside of the storage volume is 20 mbar. The material in question is, for example, e-PTFE (Gore-Tex), perforated silicone, or a fibrous material, such as felt. e-PTFE is a material composed of 100% perfluorinated material.This material has the advantage of combining breathability with hydrophobic and oleophobic properties, making it a good material for a breathing solution that also provides protection against liquids and solid particles. Felts or other woven materials, for example, those made from animal, plant, or synthetic materials, can also be used. In this case, while these materials can be filtering, they may be less effective in terms of water and dust resistance. A simple felt or fabric can be coated with a hydrophobic and / or oleophobic finish, which, however, may degrade its air permeability. The level of protection it provides against dust and water is defined, for example, by the IP67 standard or certification.The protection rating will depend on the intended stress on the part in which the membrane is incorporated, for example, the stress on the external environment: for the IP67 level, immersion for 30 minutes under 1 meter of water is considered; IP68 can also be considered, depending on the application, with immersion for 200 hours under 2 meters of water. Breathing membranes, breathing and bursting membranes, and bursting membranes can be splash-resistant, and in this case, they can simply be made of felt; however, in the case of prolonged immersion, the pore size can be smaller and the surface tension of the material to withstand these stresses will be greater.

[0066] The second zone 4, 4a, 4b, 4c, designed to burst at a pressure difference above the first threshold Pb, is, for example, a completely closed membrane. It is, for example, a thin film or a multilayer. It is, for example, made of a polypropylene or polyethylene type material, or a plastic material, or a material of the e-PTFE type (for example, with a different thickness and / or air permeability characteristics than those above, for example, to be more airtight). Alternatively, it may be made of a natural material, for example, natural or synthetic fiber(s), or hemp, or coconut, etc.

[0067] Generally speaking, in this application, the burst pressure level can be defined either by the material's resistance to tensile stress (dependent on the Young's modulus expressed in MPa), or as the strength of the weld of the diaphragm to a part (for example, a support or piston, for example, also made of plastic), or as a temperature resistance level. Therefore, the burst pressure level can be adjusted by one or more of these parameters.

[0068] The two zones or the two parts of the membrane can be assembled:

[0069] - for example by means of a film 3 intended for this purpose ([Fig.1C], but this film is applicable to the other examples); this film deposited on the membrane has adhesion properties; it is for example a PE (Polyethylene) film used to allow thermal adhesion; - or by means of an adhesive 3' intended to be deposited on a support such as the support 24 shown below ([Fig.lC], but this adhesive is applicable to the other examples);

[0070] - or by welding 5 ([Fig.1D]) via a heating process of the membrane or plastic; for example, a heat-sealing process commonly used for materials such as aluminized polypropylene or polyethylene films, like those used for sealing vacuum food packaging films; alternatively, they can be sealed using an ultrasonic process. This welding method 5 is applicable to the other examples (Figures 1A-1C).

[0071] In the case where water tightness is less restrictive (for example with only a level of resistance to water spray and not under immersion under one or more meters of water for 30 minutes to a few hours), the 2 parts 2 (resp. 2a, 2b, 2c), 4 (resp. 4a, 4b, 4c) of the membrane can be held mechanically, for example by blocking (in the devices presented below, between the piston and a clipped cover) without welding.

[0072] A membrane according to the invention, as described above, can be used in a breathing valve for an energy storage device in electrochemical form.

[0073] Figures 2A - 2E represent aspects of an example embodiment of a valve 20 that can incorporate a membrane according to the invention, for example as described above.

[0074] It comprises a fixed body 10, shown here placed in a dedicated orifice of the casing 30 of an energy storage device in electrochemical form, for example, a battery pack. This body 10 is fixed, for example, by means 11, 1a, which can be attached, welded, or crimped; these are, for example, screws or rivets. These means 11, 1a are preferably sealed or equipped with means (one or more seals) that ensure their sealing. The body 10 is provided with, or has through it, one or more orifices 10i, 102, 103,... (see [Fig. 2E]), through which a material, for example, a fluid, can flow during respiration, in a direction from the outside of the valve to the inside of the valve, or vice versa, depending on the pressure difference on either side of the valve. It can also be provided with a central orifice 100 through which a piston (or rod or bar) 8 of a support 24 (described below) can move.

[0075] The internal volume of the casing and valve is designated by the reference V;, the external volume by the reference Ve.

[0076] A seal 29 can ensure a seal between the periphery of the body 10 and the casing 30.

[0077] In this example, this body has rotational symmetry about an axis AA'. However, other shapes can be achieved, particularly depending on the shape of the different zones of a membrane, as already explained above for certain membranes according to the invention. The body 10 may include an outer circular lip 22 on which a support 24 for a flat membrane 100 can be positioned. This membrane 100 is a membrane according to the invention: it can be detached or destroyed (by explosion or bursting) by a certain pressure difference between the two sides of the membrane, for example, by a pressure difference PrPe between the inner and outer volumes greater than or equal to Pb

[0078] The support 24 may be grid-shaped or have ribs arranged in a star pattern around the center ([Fig. 2C]); it may be provided with a circular reinforcement 24 between the center and the periphery ([Fig. 2D]). It may be between:

[0079] - a first predominantly flat face 24; (this face is turned towards the interior of the enclosure when the valve is mounted on it);

[0080] - a second, mainly flat face 24th (this face is turned outwards) of the enclosure when the valve is mounted on the latter), against, or opposite, which membrane 100 can be applied.

[0081] The support 24 is itself provided with or traversed by one or more orifices 24r 245... (see Figures 2C and 2D) through which a material, for example a fluid such as air, can flow during respiration, in a direction from the outside of the valve, or the second face 24e of the support 24, towards the inside of the valve, or towards the first face 24 of the support 24, or in the opposite direction. It may also be provided with a piston (or rod or bar) 8, to one end of which it is fixed.

[0082] The body 10 may include or be extended by a central cylindrical part 6, which extends towards the inside of the casing and in which the piston 8 will be able to slide.

[0083] At least one compression spring 12 maintains the support 24 in a normally closed position against the body 10, thus allowing, through the membrane 100 it carries, a circulation of atmosphere or liquid or fluid or material between the inner volume V; and the outer volume Ve of the envelope, in one direction or another, perpendicular or substantially perpendicular to the plane defined by the flat membrane 100.

[0084] The precision of the spring determines the opening precision. Preferably, a precise or very precise spring is used, which allows, for example, to open the valve at low pressure to within a few millibars of pressure and with a very good tolerance of less than 7%. It is also possible to easily vary the pressure level by choosing a stronger or weaker spring with a greater or lesser stiffness.

[0085] Stiffness and opening force are therefore two parameters influencing the opening of the valve.

[0086] A lateral seal 15 can be disposed between the periphery of the support 24 and the body 10 to reinforce the seal when the support 24 is in contact with the body 10.

[0087] A part 14 forming a stop limits the spring's travel: the closer this stop is positioned along the piston 8 to the support 24 (and the diaphragm 100), the more the spring is compressed and the greater the pressure of the material (for example, a fluid such as air) that must be applied to open the valve 20. In the representation of [Fig. 2A], this part 14 is fixed to the piston 8 on the side of the outer volume Ve of the casing. In other words, the spring can push back the support 24 (and the diaphragm it carries) until it is blocked by the body 10.

[0088] The stop 14 is therefore in the internal volume V;.

[0089] According to a preferred embodiment, the body 10 and the support 24 have rotational symmetry about the axis AA'. However, as explained above, other shapes are possible. The piston 8 moves in translation along this axis AA', in this example under the action of the spring 12 and / or a pressure or pressure difference between the inside and outside of the valve or the casing 30. If the support and / or the body has a shape other than circular, it can nevertheless move in translation along an axis AA', preferably substantially perpendicular to the wall 30 in which the valve can be installed.

[0090] The body 10 may include a lower lip lOi which rests on the envelope 30 and in the center of which is the axis of movement of the piston 8.

[0091] The spring 12 can be straight or conical (as in [Fig.2A]). A conical spring can be more compact, because its coils are not contiguous.

[0092] The membrane 100 is held against the support 24 by means of a grid 25 ([Fig. 2A]), which may be provided with a circular reinforcement 25r, or a ring 25a ([Fig. 2B]). A grid 25 makes it possible to better and more uniformly distribute the force exerted by the air on the membrane and thus limit the burst pressure (it creates a resistance that will limit the effect of tension on the membrane).

[0093] With such a device, a first stage, called respiration, can take place through membrane 100. Respiration allows the pressure to equalize between the external environment and the interior of the battery volume. The pressure differences between the outside and inside result from changes in atmospheric pressure generated, for example, by changes in temperature and / or altitude, etc. Preferably, and as already explained above, membrane 100 is watertight and dustproof to guarantee the integrity of the battery pack containing the electrochemical cells.

[0094] In a second step, the valve, or more precisely the support 24 relative to the body 10, opens in the event of internal gas release or a significant increase in pressure and / or temperature inside the battery pack. This opening occurs from a certain pressure level P2 in the volume Vi, which is a function of the surface area over which the force F of the fluid (air / gas) is exerted on the membrane 24 with surface area S (P2 = F / S) and the properties of the spring and its state of compression. The force Fr exerted by the spring is Fr = k Lr (k being the spring constant), Lr being the compression length of the spring. As soon as F > Fr, the valve opens (the fluid force causing the opening is greater than the force exerted by the spring to open it; the force exerted by the spring will increase as the opening occurs due to the compression effect of the spring). For example, such an opening occurs from 40 mbar.A volume of fluid can then escape through the opening or orifice created between body 10 and support 24.

[0095] A rupture of the membrane 100 can occur during a 3rd step. The aim is then to considerably increase the flow rate passing through the part 10 in order to limit the increase in pressure and / or temperature in the battery pack, which, for example, can result from a thermal runaway of an electrochemical device contained in the casing 30. The full opening of the piston, obtained during the 2nd step, not being sufficient for this, the membrane 100 will be detached or destroyed for a pressure difference level Pi-Pe greater than or equal to Pi (for example, from a minimum of 150 mbar and / or a temperature from 100°C). Between Pi and P2, the opening took place according to the 2nd step described above; However, during this third stage, the piston's opening towards the external volume Ve increases significantly to compensate for the internal increase in pressure P and / or temperature. At the end of this third stage, the support 24 tends to close towards the body 1, but it can reopen under the action of the fluid escaping from the casing 30.

[0096] The example in Figures 2A-2E was given for a breathing and bursting membrane. Such a membrane combines these two functions: a breathing function, allowing pressure equalization, and a bursting function at a given pressure value, for example, above 150 mbar. During bursting, the bursting membrane can, for example, either detach from its support (for example, because the weld or other fastening means is designed for this purpose) or be destroyed by tearing (for example, at the center of the membrane). The stress exerted by an increase in the battery's volume pressure tends to reach its rupture point. The membrane is sufficiently thin for this. The material of this membrane is, for example, an e-PTFE film or a silicone material.

[0097] Fig. 3A represents the case of a valve 20a according to the invention provided with a membrane having on the one hand a zone 2 for breathing and, on the other hand, a zone 4 for bursting, as explained above in relation to Fig. 1A (alternatively it could be a membrane of the type explained above in relation to figures IB - ID).

[0098] The assembly comprising the body 10 and the support 24 is identical or similar to what has already been described above in relation to figures 2A - 2E.

[0099] In the illustrated example, the breathing function is ensured by the central part 2 of the membrane, while the explosion function is ensured by the peripheral part 4. But, as already explained above, it could be the other way around.

[0100] The operation of this device is the same as the previous one, with a 1st pressure difference threshold P, PL equal to P2 for the opening during the 2nd step and a 2nd pressure difference threshold P, Pe equal to Pi(Pi >P2) for the explosion or tearing of the membrane during the 3rd step, the difference being that it is then the peripheral part 4 of the membrane that explodes or is torn.

[0101] The membrane can be held against the support 24 using a grid 25 (as illustrated in [Fig.3B]) or using a grid 25 and / or a ring 25a (as illustrated in [Fig.3C]).

[0102] Figure 5 represents an envelope 30 energy storage device, for example in electrochemical form, for example still comprising a plurality of block- battery 110. This enclosure 30 is equipped with a valve 20 (or 10a, 20b, 20c) according to the invention.

[0103] A valve or an energy storage device according to the invention can be advantageously used in the context of an exothermic incident occurring inside the envelope 30 which can be that of a battery used for example in the field of transport, for example in a vehicle such as a car or a truck or an airplane, propelled by a thermal engine or an electric motor or a hybrid engine.

[0104] In this case, the vehicle may include a passenger compartment, for example occupied by passengers and / or goods; the valve 20 according to the invention allows gases under pressure and / or overheating to be evacuated to an area not occupied by passengers and / or goods. Thus, no gas under pressure and / or overheating can escape towards the passenger compartment in which the passengers and / or goods are located.

[0105] The vehicles shown in Figures 6A - 6D, each equipped with an energy storage device 30 according to the present invention, can be:

[0106] - of the type for transporting persons and / or goods;

[0107] - and / or of autonomous type;

[0108] - and / or type 200 motor vehicle ([Fig.6A]) and / or construction vehicles, for example of the excavator or digger type, or of the aircraft type (for example: airplane 210, [Fig.6B]) or of the space type, for example a space station or a satellite; or, alternatively, of the type used in the maritime field, for example a boat 220 ([Fig.6C]) or a ship or a vessel or a submarine, or of the type used in the railway field, for example a locomotive 230 ([Fig.6D]) or a wagon, or more generally of the type used as an air, land or sea locomotion device.

[0109] Alternatively, not shown, a 2 or 3 wheeled vehicle may be equipped with an energy storage device 30 according to the present invention.

[0110] The invention relates in particular to an application to batteries, in particular lithium-ion batteries, which consist of a sealed casing comprising a set of unit cells and most of the time electronic and power components for their interconnection and control.

Claims

Demands

1. Breathing valve membrane (100) for an electrochemical energy storage device, comprising: - at least one first zone (2, 2a, 2b, 2c) allowing breathing, in both directions through the membrane, at least for a pressure difference between the 2 sides of the membrane below a 1st threshold (Pi); - at least one 2nd zone (4, 4a, 4b, 4c), different from the first zone (2, 2a, 2b, 2c), intended to burst for a pressure difference between the 2 sides of the membrane above the 1st threshold (Pi).

2.

3. Membrane according to claim 1, the 2 zones being juxtaposed. Membrane according to claim 1, one of the 2 zones surrounding the other zone.

4. Membrane according to any one of claims 1 to 3, the 1st zone and the 2nd zone being fixed to each other, for example by welding.

5. Membrane according to any one of claims 1 to 3, the 1st zone and the 2nd zone being fixed or assembled on or with the same support (3), for example a film or an adhesive layer.

6. Membrane according to any one of claims 1 to 5, wherein the 2nd zone (4, 4a, 4b, 4c) forms a thin layer or a multilayer and / or is made of a plastic or metallic material, for example of a polypropylene or polyethylene type material, or of e-PTFE.

7. Membrane according to any one of claims 1 to 5, wherein the 2nd zone (4, 4a, 4b, 4c) is made of natural or synthetic fibre(s), or hemp, or coconut.

8. Membrane according to any one of claims 1 to 7, wherein the first zone (2, 2a, 2b, 2c) is made of a porous material, for example e-PTFE or perforated silicone or fibrous material.

9. Membrane according to any one of claims 1 to 7, wherein the first zone (2, 2a, 2b, 2c) is made of felt or a woven material.

10. Membrane according to any one of claims 1 to 9, wherein the constituent material has at least partly hydrophobic and / or oleophobic properties and / or is provided with a hydrophobic and / or oleophobic coating and / or the membrane comprising at least one waterproof part.

11. Membrane according to any one of claims 1 to 10, wherein the first zone (2, 2a, 2b, 2c) has a flow rate between 0.2 and 3.5 L / min / cm2.

12. Valve (20, 20a, 20b) for an electrochemical energy storage device, said device comprising a casing (30), said valve itself comprising: - a valve body (10); - a first membrane (2, 4, 100, 100a), according to any one of claims 1 to 11, capable at least of bursting for a pressure difference between the 2 sides of the membrane greater than a threshold (Pi) and means (24) forming at least a first support of said first membrane (2, 4, 100, 100a); - means (8, 12) maintaining the valve in a closed state for a pressure difference between the 2 sides of the membrane less than (P2) and allowing the valve to open for a pressure between (Pi) and (P2), Pi > P2.

13. Valve according to claim 12, the first diaphragm (2, 4, 100, 100a) being held against the support (24) by means of holding means (25, 25a).

14. Valve according to claim 12 or 13, the first diaphragm (2, 4, 100, 100a) being sealed.

15. Valve according to any one of claims 12 or 14, the first membrane further allowing at least one respiration by circulation of fluid through it.

16. Valve according to any one of claims 12 to 15, the means (24) forming support being disposed at one end of a piston (8), which passes through the valve body.

17. Valve according to any one of claims 12 to 16, the means (8, 12) maintaining the valve in a closed state for a pressure difference less than (P2) and allowing opening of the valve for a pressure between (Pi) and (P2) comprising at least one spring (12), each bearing against a fixed part of the body (10) of the valve and a movable part, (14) connected to the support (24).

18. Valve according to the preceding claim, the moving part (24) linked to the support (24) comprising a stop (14).

19. Valve according to claim 17 or 18, the spring (12) being a straight or spiral spring.

20. Energy storage enclosure in electrochemical form, for example of battery type, comprising an envelope (30) containing one or more energy storage elements (110), this envelope being provided with at least one valve (20, 20a, 20b, 20c) according to any one of claims 12 to 19.

21. Vehicle, comprising a passenger compartment and / or a storage area, an engine, and at least one energy storage enclosure according to claim 20.

22. Vehicle according to claim 21, this vehicle being: - of the type for transporting persons and / or goods; - and / or of the autonomous type; - and / or of the motor vehicle and / or construction vehicle type, for example of the excavator or backhoe type, or of the aircraft or space type, or of the type used in the maritime field, for example boat or ship or craft or submarine, or of the type used in the railway field, for example locomotive or wagon.

23. Vehicle according to claim 21 or 22, this vehicle being 2-wheeled or 3-wheeled.

24. Method of operating a valve (20, 20a, 20b, 20c) of an energy storage vessel in electrochemical form according to claim 20, method in which: a) - the valve is maintained in a closed state for a pressure difference between the inside of the vessel and the outside (P;-Pe) of the vessel less than (P2); b) - the valve is in an open state for said pressure difference between (Pi) and (P2), Pi>P2; c) - the diaphragm bursts for said pressure difference greater than (Pi).

25. A method according to the preceding claim, wherein there is fluid exchange between the inside and outside of the enclosure through the first zone of the membrane at least during step a).

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