Compressed-gas storage container and vehicle

Abstract

The invention relates to a compressed-gas storage container (7, 7A, 7B, 7C) for storing a gas (H2), in particular hydrogen, in a pressurized manner, comprising a wall (9) which encloses a receiving region (10) for receiving the gas (H2), a pressure relief unit (22) for discharging the gas (H2) out of the receiving region (10), and a pyroelectric sensor fiber (23, 23A, 23B) which is designed to trigger the pressure relief unit (22) in order to discharge the gas (H2) out of the receiving region (10) if heat (Q), produced by a fire, is input into the wall (9).

Description

[0001] COMPRESSED GAS STORAGE TANK AND VEHICLE

[0002] The present invention relates to a compressed gas storage container for the pressurized storage of a gas and a vehicle with such a compressed gas storage container.

[0003] For storage and transport, hydrogen can be stored either in gaseous form in a compressed gas storage container at several hundred bar overpressure or in liquid form at cryogenic temperatures. For use in or on vehicles, especially in or on passenger cars, it is advantageous to store the hydrogen in gaseous form in a compressed gas storage container as mentioned above due to space constraints.

[0004] According to legal regulations, in the event of extreme heat exposure, such as a vehicle fire, the hydrogen must be able to be released from the compressed gas storage vessel in a controlled manner, reliably preventing the vessel from bursting. According to internal company experience, pressure release devices (PRDs or thermally activated pressure release devices, TPRDs) can be used for this purpose. These devices are thermally triggered in the event of a fire and release the hydrogen in a controlled manner.

[0005] Due to legal requirements, such a pressure relief unit may only be triggered mechanically or using an analog circuit. Activation using software, for example, via a vehicle control unit, is not permitted for safety reasons. The pressure relief unit can only be triggered if heat, for example, due to a vehicle fire, is introduced directly into the pressure relief unit. Thus, essentially only local heat or fire detection is possible. This requires improvement. Against this background, one object of the present invention is to provide an improved compressed gas storage container.

[0006] Accordingly, a compressed gas storage container for the pressurized storage of a gas, in particular hydrogen, is proposed. The compressed gas storage container comprises a wall enclosing a receiving area for receiving the gas, a pressure relief unit for releasing the gas from the receiving area, and a pyroelectric sensor fiber configured to trigger the pressure relief unit upon fire-induced heat input into the wall, thereby releasing the gas from the receiving area.

[0007] Because the pyroelectric sensor fiber directly triggers the pressure relief unit, the pressure relief unit can be triggered without an external energy source, thus releasing the gas from the receiving area. This is particularly advantageous with regard to meeting legal requirements in the event of a fire. Furthermore, the pyroelectric sensor fiber allows for spatial separation of the detection of heat ingress into the wall from the pressure relief unit. With the help of the pyroelectric sensor fiber, fire detection can therefore be decoupled from the pressure relief unit. This advantageously eliminates the limitation to local fire detection.

[0008] The compressed gas storage vessel may also be referred to as a compressed gas storage tank, hydrogen compressed gas storage vessel, hydrogen compressed gas storage tank, hydrogen storage vessel, or the like. In particular, the compressed gas storage vessel is suitable for storing and / or transporting hydrogen. However, any other gases can also be stored in the compressed gas storage vessel. In the following, it is assumed that the gas is hydrogen. The terms "gas" and "hydrogen" can therefore be interchanged arbitrarily.

[0009] The term "compressed gas storage vessel" in this context means that the gas can be stored in its gaseous state under pressure in the compressed gas storage vessel. For example, the gas within the compressed gas storage vessel can be pressurized to a pressure of 800 to 1,000 bar. In particular, liquefaction of the gas is not intended in this case. The gas can be introduced or injected into the receiving area in gaseous form.

[0010] The compressed gas storage container is preferably part of a vehicle. The vehicle can have several such compressed gas storage containers. The compressed gas storage container can be suitable for providing the gas to a consumer, in particular a fuel cell, of the vehicle at a suitable supply pressure and a suitable supply temperature. The compressed gas storage container can be part of a gas supply system or hydrogen supply system of the consumer. However, the compressed gas storage container can also be used in immobile applications, for example, in building technology. In particular, the compressed gas storage container can be used in building heating or for combined heat and power plants.

[0011] The wall preferably comprises a load-bearing casing, which is made at least in sections from a fiber-reinforced plastic. The casing encloses an optional lining. The lining is arranged within the casing. The casing thus preferably completely encapsulates the lining. The lining is preferably gas-tight. The lining can also be referred to as a liner. The lining can comprise a plastic material, a metallic material, and / or a fiber-reinforced plastic. The compressed gas storage vessel, and thus also the wall, is preferably cylindrical. The compressed gas storage vessel or the wall is assigned a symmetry or central axis, to which the compressed gas storage vessel or the wall can be constructed rotationally symmetrically.The wall preferably comprises a hollow cylindrical or tubular base section, which is closed on both sides by lid-shaped or dome-shaped wall end sections. The casing and lining are provided both in the area of ​​the base section and in the area of ​​the wall end sections.

[0012] The fact that the wall "encloses" or "delimits" the receiving area means, in this case, in particular that the wall defines a geometry or boundaries of the receiving area. The gas is thus contained within the wall in the receiving area. The receiving area is, in particular, a cavity enclosed by the wall. The receiving area has, in particular, a cylindrical geometry. The receiving area is sealed gas-tight from the surroundings of the compressed gas storage container by means of the wall. The receiving area can be designed rotationally symmetrically to the central axis.

[0013] The pressure relief unit is, in particular, a so-called Pressure Release Device (PRD) or Thermally Activated Pressure Release Device (TPRD). The pressure relief unit preferably comprises a valve and a pyrotechnic charge for triggering or opening the valve. The fact that the pressure relief unit is configured to "blow off" the gas from the receiving area is understood in this case to mean, in particular, that with the aid of the pressure relief unit, the gas can be completely released from the receiving area within a very short period of time, for example, within a few milliseconds to a few seconds. This reliably prevents an undesirable pressure increase within the compressed gas storage container in the event of a fire, which could lead to an explosion of the compressed gas storage container.

[0014] With the help of the pyroelectric sensor fiber, fire detection can be at least partially spatially decoupled from the pressure relief unit. In this case, the pyroelectric sensor fiber functions in particular as both a sensor and an energy source. With the help of the pyroelectric sensor fiber, complete monitoring of the entire outer side of the wall is possible. For this purpose, the pyroelectric sensor fiber is arranged on the outer side or embedded in the casing of the wall. The pressure relief unit, together with the pyroelectric sensor fiber, forms a pressure relief device for the compressed gas storage vessel. The pyroelectric sensor fiber is particularly elastically deformable and can therefore be wound onto the wall in a helical or spiral manner.

[0015] The pyroelectric sensor fiber comprises a pyroelectric material. The pyroelectric material can be a piezoelectric semiconductor crystal. A temperature change of the pyroelectric material leads to a measurable change in an electrical voltage between a first electrode and a second electrode of the pyroelectric sensor fiber. Thus, the pyroelectric sensor fiber provides electrical energy. This electrical energy can be used to trigger the pressure relief unit. "Triggering" the pressure relief unit is understood here to mean, in particular, that the pyrotechnic charge of the pressure relief unit is ignited, so that the valve of the pressure relief unit is opened to release the gas into the environment.

[0016] In the present case, a "fire-related heat input" is to be understood in particular as meaning that the compressed gas storage container is exposed to a fire or a flame, whereby heat, in particular in the form of infrared radiation or direct flame contact, is introduced into the storage container, in particular into the wall, and thus also into the pyroelectric sensor fiber.

[0017] According to one embodiment, the pressure relief unit comprises a valve for releasing the gas from the receiving area and a pyrotechnic charge, wherein the pyroelectric sensor fiber ignites the pyrotechnic charge to open the valve.

[0018] The valve is preferably closed in an initial state. By igniting the pyrotechnic charge, the valve is moved from a closed state to an open state. The valve is preferably an on-off valve. This means that the valve is either completely closed or completely open. The pyrotechnic charge can be ignited using a glow bridge, which can be energized using the pyroelectric sensor fiber. The glow bridge begins to glow, igniting the pyrotechnic charge. This opens the valve to release the gas into the environment. By igniting the pyrotechnic charge, a component of the valve, for example a valve body or a valve tappet, can be moved to open the valve.

[0019] According to a further embodiment, the pyroelectric sensor fiber comprises a first electrode, a second electrode and a pyroelectric material arranged between the first electrode and the second electrode.

[0020] For example, the first electrode comprises a conductive material, such as a metal, a plastic filled with conductive particles, carbon-based fibers, or the like. The same can apply to the second electrode. The pyroelectric material can be applied to the first electrode, which in turn is coated with another conductive material that forms the second electrode. The pyroelectric sensor fiber can have any desired geometry in cross-section. For example, the pyroelectric sensor fiber has a wire-shaped first electrode and a tubular second electrode. The first electrode can be arranged within the second electrode. The pyroelectric material is arranged between the first electrode and the second electrode, and the first electrode is embedded in the pyroelectric material in such a way that the first electrode and the second electrode do not contact each other.The pyroelectric material can also be referred to as a sensor material. The electrodes can also be plate-shaped or foil-shaped.

[0021] According to a further embodiment, the pyroelectric sensor fiber is arranged in or on the wall.

[0022] The pyroelectric sensor fiber can be installed in the sheathing, particularly in the fiber-reinforced plastic of the sheathing, during the winding process of the sheathing of the wall. The degree of coverage of the pyroelectric sensor fiber with the fiber-reinforced plastic, and thus the detection area for fire detection, can be adjusted by the winding process.

[0023] According to a further embodiment, the pyroelectric sensor fiber is embedded at least in sections in the wall.

[0024] In this case, the pyroelectric sensor fiber can be covered at least partially by the fiber-reinforced plastic. The pyroelectric sensor fiber can also be completely covered by the fiber-reinforced plastic. This protects the pyroelectric sensor fiber from damage within the fiber-reinforced plastic. Viewed in a radial direction of the compressed gas storage container, the pyroelectric sensor fiber can be embedded 1 mm to a maximum of 5 mm deep into the wall. According to a further embodiment, the pyroelectric sensor fiber winds helically around the wall, viewed along a longitudinal direction of the compressed gas storage container.

[0025] The longitudinal direction runs along the aforementioned central axis. This means, in particular, that the pyroelectric sensor fiber has a helical or helical geometry. A multiple helix or a crossed helix is ​​also possible. Furthermore, the pyroelectric sensor fiber can be designed, in particular, to be spiral, multiple helix, crossed helix, or the like. The pitch of this helical geometry of the pyroelectric sensor fiber can be arbitrarily selected. For example, windings of the pyroelectric sensor fiber can be arranged closer together or further apart. This can influence the sensitivity of the pressure relief device. Viewed along the longitudinal direction, a distance between the windings or a winding spacing of the pyroelectric sensor fiber can preferably be a maximum of 100 mm. This aforementioned winding spacing is particularly preferably a maximum of 50 mm.

[0026] According to a further embodiment, the compressed gas storage container has a plurality of pyroelectric sensor fibers, wherein all of the plurality of pyroelectric sensor fibers are jointly assigned to the pressure relief unit.

[0027] This means, in particular, that a pressure relief unit is assigned several pyroelectric sensor fibers. This can improve the sensitivity of the pressure relief device. The pyroelectric sensor fibers can have different lengths. According to a further embodiment, the several pyroelectric sensor fibers are arranged parallel to one another and / or cross one another.

[0028] The multiple pyroelectric sensor fibers can also be arranged at least partially parallel and partially intersect each other. If the pyroelectric sensor fibers do intersect, a network-like arrangement of the pyroelectric sensor fibers can be realized on or in the wall.

[0029] According to a further embodiment, the compressed gas storage container has a capacitor for storing electrical energy generated by means of the pyroelectric sensor fiber.

[0030] The capacitor is connected, in particular, between the pyroelectric sensor fiber and the pressure relief unit. The capacitor can be a so-called surge or pulse capacitor. A "pulse capacitor" of this type is understood here to be a DC capacitor that absorbs or releases a strong, usually very short, but high-energy current pulse. This makes it possible to ignite the pyrotechnic charge with the help of the current pulse released by the capacitor.

[0031] According to a further embodiment, the compressed gas storage container has an electrical circuit comprising the capacitor and the pyroelectric sensor fiber, wherein the electrical circuit is configured to release the electrical energy stored in the capacitor as a function of a variable indicative of a charging of the capacitor in order to trigger the pressure relief unit.

[0032] The electrical circuit is, in particular, part of the pressure relief device. The electrical circuit is, in particular, an analog electrical circuit. The variable indicative of the charging of the capacitor can be a voltage measured or present on the capacitor. For example, when a predetermined voltage is reached, the capacitor is discharged to trigger the pressure relief unit by igniting the pyrotechnic charge of the pressure relief unit, which opens the valve of the pressure relief unit.

[0033] According to a further embodiment, the electrical circuit comprises a control element which detects the indicative variable, and a switching element which can be controlled by the control element as a function of the indicative variable in order to release the electrical energy stored in the capacitor to trigger the pressure relief unit.

[0034] In particular, the control element is connected to the switching element in such a way that, at a predetermined value of the indicative variable, the control element controls the switching element in such a way that the capacitor is discharged to trigger the pressure relief unit.

[0035] According to a further embodiment, the control element is connected in parallel to the capacitor, wherein the switching element is connected in parallel to the capacitor, and wherein the control element controls the switching element by means of a control output.

[0036] Accordingly, the control element is connected to the switching element via the control output. The switching element can be a relay or a transistor, for example.

[0037] According to another embodiment, the control element is a voltmeter, and the switching element is a transistor. In particular, the transistor can be an NPN (negative-positive-negative) transistor. The transistor has a base, an emitter, and a collector. The control output of the control element is connected to the base.

[0038] According to a further embodiment, the pressure relief unit is attached to a dome-shaped wall end section of the wall.

[0039] For example, an inlet nozzle for admitting the gas into the compressed gas storage container can be mounted on a first wall end section, with the pressure relief unit mounted on a second wall end section. Reverse mounting is also possible. Furthermore, the pressure relief unit can also be integrated into the inlet nozzle. This results in a compact design.

[0040] Furthermore, a vehicle, in particular a motor vehicle, with at least one such compressed gas storage container is proposed.

[0041] The vehicle can have a plurality of such compressed gas storage containers. The compressed gas storage container can, for example, be arranged in the region of a floor of the vehicle. The vehicle can have a consumer, in particular a fuel cell, which is supplied with the gas with the aid of the compressed gas storage container. The vehicle can, in particular, be an electric vehicle or a hybrid vehicle. However, the vehicle can also have an internal combustion engine. The vehicle can also be a commercial vehicle, for example a truck. Furthermore, the vehicle can also be an aircraft, a watercraft, or a rail vehicle. The vehicle is particularly preferably a passenger car. The embodiments and features described for the proposed compressed gas storage container apply accordingly to the proposed vehicle, and vice versa.

[0042] "One" in this case is not necessarily limited to a single element. Rather, multiple elements, such as two, three, or more, may be included. Any other counting term used here should not be understood as implying a limitation to the exact number of elements mentioned. Rather, numerical deviations upwards and downwards are possible, unless otherwise stated.

[0043] Further possible implementations of the compressed gas storage container and / or the vehicle also include combinations of features or embodiments described above or below with regard to the exemplary embodiments that are not explicitly mentioned. In this case, the person skilled in the art will also add individual aspects as improvements or additions to the respective basic form of the compressed gas storage container and / or the vehicle.

[0044] Further advantageous configurations and aspects of the compressed gas storage container and / or the vehicle are the subject of the dependent claims and the exemplary embodiments of the compressed gas storage container and / or the vehicle described below. The compressed gas storage container and / or the vehicle are explained in more detail below using preferred embodiments with reference to the accompanying figures.

[0045] Fig. 1 shows a schematic side view of an embodiment of a vehicle!

[0046] Fig. 2 shows a schematic sectional view of an embodiment of a compressed gas storage container for the vehicle according to Fig. 1; Fig. 3 shows a further schematic sectional view of the compressed gas storage container along section line III-III of Fig. 2;

[0047] Fig. 4 shows the detailed view IV according to Fig. 2;

[0048] Fig. 5 shows a schematic side view of the compressed gas storage container according to Fig. 2;

[0049] Fig. 6 shows a schematic sectional view of an embodiment of a pyroelectric sensor fiber for the compressed gas storage container according to Fig. 2;

[0050] Fig. 7 shows a schematic side view of another embodiment of a compressed gas storage container for the vehicle according to Fig. 1;

[0051] Fig. 8 shows a schematic view of an embodiment of a pressure relief device for the compressed gas storage container; and

[0052] Fig. 9 shows a schematic side view of another embodiment of a compressed gas storage container for the vehicle according to Fig. 1.

[0053] In the figures, identical or functionally identical elements have been provided with the same reference numerals unless otherwise stated.

[0054] Fig. 1 shows a schematic side view of an embodiment of a vehicle 1. The vehicle 1 is a motor vehicle, in particular an electric vehicle or a hybrid vehicle. However, the vehicle 1 can also be powered by an internal combustion engine. The vehicle 1 can also be a commercial vehicle, for example a truck, a harvester, or a construction machine. Furthermore, the vehicle 1 can also be a military vehicle. Furthermore, the vehicle 1 can also be an aircraft, a watercraft, or a rail vehicle. However, it is assumed below that the vehicle 1 is a motor vehicle, in particular a passenger car.

[0055] The vehicle 1 comprises a body 2, which encloses a passenger compartment or vehicle interior 3 of the vehicle 1. A driver and passengers can be located in the vehicle interior 3. The body 2 separates an environment 4 of the vehicle 1 from the vehicle interior 3. The vehicle interior 3 is accessible from the environment 4 by means of doors.

[0056] The vehicle 1 comprises a chassis with several wheels 5, 6. The number of wheels 5, 6 is fundamentally arbitrary. Preferably, the vehicle 1 has four wheels 5, 6. However, the vehicle 1 can also have, for example, six wheels 5, 6. The wheels 5, 6 are part of a chassis of the vehicle 1. Only two wheels 5, 6 can be driven. However, all wheels 5, 6 can also be driven. In this case, the vehicle 1 is an all-wheel drive vehicle.

[0057] The vehicle 1 comprises a compressed gas storage container 7 for the pressurized storage of a gas, in particular hydrogen. The compressed gas storage container 7 is preferably located on or in the region of a floor or floor structure of the vehicle 1. The compressed gas storage container 7 can be arranged outside the body 2. The vehicle 1 can have multiple compressed gas storage containers 7.

[0058] In principle, the compressed gas storage vessel 7 is not only suitable for use on a vehicle 1, but can also be used for any other application. For example, the compressed gas storage vessel 7 can also be used for immobile applications, in particular in building technology or for emergency power supplies. Furthermore, the compressed gas storage vessel 7 can be used in building heating or for combined heat and power plants. However, the following assumes that the compressed gas storage vessel 7 is used for a mobile application, namely in or on the vehicle 1.

[0059] With the aid of the compressed gas storage container 7, the gas stored in the compressed gas storage container 7 can be supplied to a consumer 8 of the vehicle 1 at a suitable supply pressure and a suitable supply temperature. The consumer 8 is preferably a fuel cell. A "fuel cell" is understood here to be a galvanic cell that converts the chemical reaction energy of a continuously supplied fuel, in this case hydrogen, and an oxidizing agent, in this case oxygen, into electrical energy. The resulting electrical energy can be used, for example, to drive an electric motor (not shown), which in turn drives the wheels 5, 6 or at least two of the wheels 5, 6.

[0060] Fig. 2 shows a schematic sectional view of an embodiment of a compressed gas storage container 7A as mentioned above. Fig. 3 shows a further schematic sectional view of the compressed gas storage container 7A along the section line HI-IH of Fig. 2. Fig. 4 shows the detailed view IV according to Fig. 2. In the following, reference is made simultaneously to Figs. 2 to 4.

[0061] The compressed gas storage container 7A is suitable for storing a gas, in this case hydrogen H2, in gaseous form under high pressure and releasing it again as needed. For example, the compressed gas storage container 7A is operated at a pressure of several hundred bar, for example, from 800 to 1,000 bar. The compressed gas storage container 7A can also be referred to as a compressed gas storage tank, hydrogen compressed gas storage container, hydrogen compressed gas storage tank, or hydrogen storage container. In principle, the compressed gas storage container 7A is suitable for receiving or storing any gas. However, it is assumed below that the gas is hydrogen H2. The terms "gas" and "hydrogen" are therefore interchangeable. As previously mentioned, the hydrogen H2 is stored in its gaseous state in the compressed gas storage container 7A. The hydrogen H2 is thus single-phase.Therefore, preferably there is no liquid phase and thus no phase boundary within the compressed gas storage vessel 7A.

[0062] The compressed gas storage container 7A comprises a container wall or wall 9 that encloses a receiving area 10 for receiving the hydrogen H2. The gaseous hydrogen H2 is received in the receiving area 10. The receiving area 10 is cylindrical. A geometry or a spatial extent of the receiving area 10 is defined or limited by the wall 9. The receiving area 10 is a hollow space completely enclosed by the wall 9. The wall 9 is, as explained below, multi-layered or multi-layered. This means that different materials form the wall 9 in a layered structure.

[0063] The compressed gas storage vessel 7A is assigned a coordinate system with a longitudinal direction or x-direction x, a transverse direction or y-direction y, and a vertical direction or z-direction z. The directions x, y, z are oriented perpendicular to each other. A longitudinal direction L of the compressed gas storage vessel 7A runs along the x-direction x. This means that the longitudinal direction L and the x-direction x are identical. A direction of gravity g is opposite and oriented parallel to the z-direction z.

[0064] The pressure gas storage container 7A or the wall 9 is provided with a

[0065] A symmetry or central axis 11 is assigned to the compressed gas storage vessel 7A or the wall 9, respectively, to which the compressed gas storage vessel 7A or the wall 9 is essentially rotationally symmetrical. "Essentially" rotationally symmetrical includes an at least slightly oval cross-section. The central axis 11 runs parallel to the x-direction x. Accordingly, the central axis 11 also runs along the longitudinal direction L. A radial direction R of the compressed gas storage vessel 7A or the wall 9 is oriented perpendicular to the central axis 11 and away from it in the direction of the wall 9.

[0066] The wall 9 can also be referred to as a container wall, shell, enclosure, or wall. The wall 9 is constructed rotationally symmetrically to the central axis 11. In cross-section, the wall 9 is therefore preferably circular. However, the wall 9 can also be oval or slightly oval in cross-section. The wall 9 comprises a tubular or hollow-cylindrical base section 12, which is constructed rotationally symmetrically to the central axis 11.

[0067] On each end face, i.e., on the left and right in the orientation of Fig. 2, a first cover section or first wall end section 13 and a second cover section or second wall end section 14 are provided on the base section 12. The wall end sections 13, 14 are dome-shaped or cupola-shaped and are each rotationally symmetrical to the central axis 11. The wall end sections 13, 14 can also be referred to as cover sections. The wall end sections 13, 14 are curved outwards with respect to the receiving area 10. The base section 12 and the wall end sections 13, 14 are firmly, in particular non-detachably, connected to one another. The wall 9 has a cylindrical geometry.

[0068] The wall 9 comprises a load-bearing casing 15 (Figs. 3 and 4) made of a fiber-reinforced plastic material or a fiber-reinforced plastic. The casing 15 is external and thus faces the environment 4. This means that the casing 15 borders the environment 4. The "load-bearing" nature of the casing 15 means, in this case, in particular that the casing 15 absorbs all or at least a large portion of the loads acting on the wall 9 or on the compressed gas storage container 7A. The loads can result from the pressurized hydrogen H2 itself and / or from external loads, for example, in a traffic accident.

[0069] The sheathing 15 can also be referred to as a jacket, covering, support layer, outer layer, or outer layer of the wall 9. The sheathing 15 is preferably constructed in layers or layers from the fiber-reinforced plastic. However, this does not preclude the sheathing 15 from also containing metallic components. The sheathing 15 has an outer side 16 facing the environment 4 and an inner side 17 facing the receiving area 10 (Fig. 4).

[0070] A fiber-reinforced plastic as mentioned above comprises a plastic material, in particular a plastic matrix, in which fibers, for example natural fibers, glass fibers, carbon fibers, aramid fibers, or the like, are embedded. The plastic material can be a thermoset, such as an epoxy resin or a vinyl ester-based resin. However, the plastic material can also be a thermoplastic. The fibers can be continuous fibers.

[0071] The sheath 15 is preferably a one-piece component, in particular a one-piece component. "One-piece" or "single-piece" is understood here to mean that the sheath 15 forms a single component and is not composed of different and separable parts or components. "One-piece" means here that the sheath 15 is made entirely of the same material, namely the fiber-reinforced plastic. The sheath 15 is provided both on the base section 12 and on the two wall end sections 13, 14.

[0072] In addition to the casing 15, the wall 9 has a lining 18 lining the casing 15. The lining 18 can also be referred to as the inner layer or inner ply of the wall 9. To produce the casing 15, the casing 15 can be wound onto the lining 18 or onto a mold or mandrel (not shown). The lining 18 is gas-tight. The casing 15 is not necessarily gas-tight. The lining 18 can comprise a fiber-reinforced plastic, various plastic materials, and / or metallic materials. The lining 18 is a so-called liner or can be referred to as the liner of the compressed gas storage vessel 7A.

[0073] The lining 18 has a tubular or hollow-cylindrical geometry. The lining 18 is constructed rotationally symmetrically to the central axis 11. The lining 18 is provided both on the base section 12 and on the wall end sections 13, 14. The lining 18 can have a layered or sheet-like structure. The casing 15 completely surrounds the lining 18 or encapsulates it.

[0074] The lining 18 comprises an outer side 19 (Fig. 4) facing the inner side 17 of the casing 15 and an inner side 20 facing the receiving area 10. The inner side 20 is in contact with the hydrogen H2 held in the receiving area 10. The inner side 20 can also be referred to as the inner side of the wall 9 or as the inner side of the compressed gas storage container 7A. The inner side 20 completely encloses the cylindrical receiving area 10 and thus defines its spatial extent.

[0075] The sheath 15 and the lining 18 are integrally bonded, in particular glued, to each other on the inner side 17 of the sheath 15 and on the outer side 19 of the lining 18. In integral bonds, the connecting parts are held together by atomic or molecular forces. Integral bonds are non-detachable connections that can only be separated by destroying the connecting elements and / or the connecting parts.

[0076] The compressed gas storage container 7A further comprises an injection nozzle or inlet nozzle 21 (Fig. 2) for injecting or admitting the hydrogen H2 into the receiving area 10. The inlet nozzle 21 is preferably provided at the first wall end section 13 of the wall 9. Alternatively, the inlet nozzle 21 can also be located at the second wall end section 14. Preferably, the inlet nozzle 21 extends through both the casing 15 and the lining 18. The inlet nozzle 21 can be made of a metallic material.

[0077] The inlet nozzle 21 is preferably designed such that it is rotationally symmetrical to the central axis 11. In particular, the inlet nozzle 21 is centered or arranged centrally with respect to the central axis 11. Alternatively, the inlet nozzle 21 can also be arranged off-center, i.e., offset relative to the central axis 11. The inlet nozzle 21 is preferably tubular or hollow-cylindrical and, in particular, has an annular cross-section. Alternatively, the inlet nozzle 21 can also have any other cross-section.

[0078] The inlet nozzle 21 can have a plurality of channels, bores, nozzles, valves, switches, and / or sensors that enable the compressed gas storage container 7A to be refueled or filled with gaseous hydrogen H2. The inlet nozzle 21 can protrude beyond the inner side 20 of the lining 18 in the region of the first wall end section 13 and thus into the receiving area 10. The inlet nozzle 21 is configured to admit or inject the hydrogen H2 into the receiving area 10 parallel to the central axis 11, or along the longitudinal direction L, or along the x-direction x.

[0079] Fig. 5 shows a schematic side view of the compressed gas storage container 7A.

[0080] According to legal regulations, in the event of severe heat exposure, for example, in the event of a vehicle fire, the hydrogen H2 can be released from the compressed gas storage vessel 7A in a controlled manner, reliably preventing bursting of the compressed gas storage vessel 7A. For this purpose, the compressed gas storage vessel 7A has at least one pressure relief unit 22 (Pressure Release Device, PRD or Thermally Activated Pressure Release Device, TPRD) mounted on the wall 9.

[0081] In particular, the pressure relief unit 22 is mounted on the second wall end section 14, whereas the inlet nozzle 21 can be mounted on the first wall end section 13. Reverse mounting is also possible. Furthermore, the pressure relief unit 22 can also be integrated into the inlet nozzle 21.

[0082] The pressure relief unit 22 is designed to release the hydrogen H2 from the compressed gas storage container 7A within a short period of time. For this purpose, the pressure relief unit 22 can, for example, have a valve and a pyrotechnic composition or a pyrotechnic charge for opening the valve. Due to legal requirements, the pressure relief unit 22 may only be triggered mechanically or with the aid of an analog circuit. Triggering with the aid of software, for example via a control unit of the vehicle 1, is not permitted for safety reasons. Since the pressure relief unit 22 is attached to the end of the wall 9, it can only be triggered when heat Q, in particular in the form of infrared radiation, for example due to a vehicle fire, is introduced into the pressure relief unit 22 and / or into the second wall end section 14.Essentially, only local heat detection or fire detection is possible.

[0083] If the compressed gas storage vessel 7A has a large extension along the longitudinal direction L, it may happen that, for example, a fire-related heat input at the first wall end section 13 is localized too late. To prevent this, it is possible to install additional pressure relief units 22. However, this leads to greater installation effort, higher costs, and poorer space utilization. This needs to be improved.

[0084] To avoid these aforementioned disadvantages, the fire detection in the compressed gas storage container 7A is at least partially spatially decoupled from the pressure relief unit 22. For this purpose, the compressed gas storage container 7A has a sensor fiber 23, with the aid of which monitoring over the entire outer side 16 of the wall 9 is possible. For this purpose, the sensor fiber 23 is arranged on the outer side 16 or embedded in the casing 15. The pressure relief unit 22, together with the sensor fiber 23, forms a pressure relief device 24. The sensor fiber 23 is deformable or bendable and can therefore be wound helically or spirally onto the wall 9. The sensor fiber 23 can be embedded in the wall 9, in particular in the casing 15.

[0085] Fig. 6 shows a schematic sectional view of an embodiment of a sensor fiber 23 as mentioned above. The sensor fiber 23 has a wire-shaped inner or first electrode 25 and a tubular outer or second electrode 26. The first electrode 25 is arranged within the second electrode 26. However, the electrodes 25, 26 can also have any other geometry. For example, the electrodes 25, 26 can be foil-shaped or strip-shaped. Between the first electrode 25 and the second electrode 26 is arranged a pyroelectric material 27, in which the first electrode 25 is embedded such that the first electrode 25 and the second electrode 26 do not contact each other. The sensor fiber 23 can be referred to as a pyroelectric sensor fiber. The sensor fiber 23 can be circular or rectangular in cross-section. The pyroelectric material 27 can be referred to as sensor material.

[0086] The first electrode 25 of the sensor fiber 23 comprises a conductive material, such as a metal, a plastic filled with conductive particles, carbon-based fibers, or the like. The pyroelectric material 27 is applied to the first electrode 25, which in turn is coated with another conductive material forming the second electrode 26.

[0087] The pyroelectric material 27 can be a piezoelectric semiconductor crystal. A temperature change of the pyroelectric material 27 leads to a measurable change in the electrical voltage between the two electrodes 25, 26. Thus, the sensor fiber 23 provides electrical energy. This electrical energy can be used to trigger the pressure relief unit 22. "Triggering" the pressure relief unit 22 is understood here to mean, in particular, that the pyrotechnic charge of the pressure relief unit 22 is ignited, so that the pressure relief unit 22 releases the hydrogen H2 into the environment 4.

[0088] Since the pyroelectric material 27 is a piezoelectric semiconductor crystal, the pyroelectric material 27 also exhibits piezoelectric properties. "Piezoelectricity" is understood here to mean the change in electrical polarization and thus the occurrence of an electrical voltage in solids when they are elastically deformed. The sensor fiber 23 can therefore also be referred to as a pyroelectric and piezoelectric sensor fiber.

[0089] The sensor fiber 23 can be installed in the sheath 15, particularly in the fiber-reinforced plastic of the sheath 15, during the winding process of the sheathing. The degree of coverage of the sensor fiber 23 with the fiber-reinforced plastic, and thus a detection area for fire detection, can be adjusted by the winding process. The sensor fiber 23 reacts, in particular, to externally introduced infrared radiation, such as occurs during a fire, with a temporary voltage. The amplitude of this voltage depends on the particular pyroelectric material 27 selected and the intensity of the infrared radiation.

[0090] The electrical energy generated by the sensor fiber 23 can be used to trigger the pressure relief unit 22. To trigger the pressure relief unit 22, for example, a pyrotechnic charge as mentioned above can be ignited, which opens a valve of the pressure relief unit 22 as mentioned above to release the hydrogen H2 from the compressed gas storage container 7A, resulting in pressure relief. An additional energy source for triggering the pressure relief unit 22 is not required. The pressure relief device 24 therefore advantageously requires no additional energy source for detecting, outputting, and processing a sensor signal from the sensor fiber 23. The aforementioned legal requirements can thus be met.

[0091] The pressure relief device 24 thus enables decentralized and / or comprehensive detection of a fire on the exterior 16 of the compressed gas storage vessel 7A, thereby increasing system safety. The location of the pressure relief, namely a position of the pressure relief unit 22 on the compressed gas storage vessel 7A, can thus be decoupled from the detection location, which has a direct positive impact on design freedom when designing the installation space for the compressed gas storage vessel 7A.

[0092] The sensor fiber 23 is primarily positioned in an outermost layer of the sheath 15, in particular the fiber-reinforced plastic, for example, in the form of a laminate. However, the sensor fiber 23 can also be wrapped into deeper layers. This protects the sensor fiber 23 from external influences. Nevertheless, the sensor fiber 23 still has sufficient access to the source of the fire for detection.

[0093] By selecting a suitable winding path during the manufacture of the compressed gas storage container 7A, the degree of coverage of the sensor fiber 23 encircling the compressed gas storage container 7A and thus a surface of the compressed gas storage container 7A capable of detection can be adjusted. To protect the sensor fiber 23 from damage during the winding process, it can be laid as part of a fiber strand, for example, made of carbon fibers, glass fibers, plastic fibers, or the like. To create redundancy, multiple sensor fibers 23 can be introduced.

[0094] A fire that occurs directly at the compressed gas storage container 7A and thus at the sensor fiber 23 causes a temporary voltage increase due to a shift in the center of gravity of the charge. A temperature can be derived from the amplitude of this voltage, which can be used as a limit for triggering a valve of the pressure relief unit 22. This ensures pressure reduction in the compressed gas storage container 7A. Fig. 7 shows a schematic side view of another embodiment of a compressed gas storage container 7B. Fig. 8 shows a schematic view of an embodiment of a pressure relief device 24 for the compressed gas storage container 7B, as mentioned above. Reference is made to Figs. 7 and 8 simultaneously below.

[0095] The compressed gas storage container 7B differs from the compressed gas storage container 7A only in that the compressed gas storage container 7B has a pressure relief device 24, which, in addition to a pressure relief unit 22 as mentioned above and a sensor fiber 23 as explained above, has a capacitor 28 connected upstream of the pressure relief unit 22. The capacitor 28 can be a so-called surge or pulse capacitor. Such a "pulse capacitor" is understood here to mean a DC capacitor, which serves to absorb or release a strong, usually very short, but high-energy current pulse.

[0096] As shown in Fig. 8, the pressure relief device 24 has an analog electrical circuit 29, by means of which the sensor fiber 23, the pressure relief unit 22, and the capacitor 28 are interconnected. The pressure relief unit 22 has a valve 30, in particular a gas valve, and a pyrotechnic charge 31 associated with the valve 30. The first electrode 25 of the sensor fiber 23 is connected as the negative pole. The second electrode 26 is connected as the positive pole. Reverse polarity can also be provided. The pyroelectric material 27 is not shown in Fig. 8.

[0097] The electrodes 25, 26 are connected to a first conductor track 32 and a second conductor track 33. A third conductor track 34 connects the two conductor tracks 32, 33 to one another, with the capacitor 28 connected to the third conductor track 34. The circuit 29 further comprises a control element 35. The control element 35 can be a voltmeter. The control element 35 is connected in parallel to the capacitor 28 by means of a fourth conductor track 36 and a fifth conductor track 37, both of which branch off from the third conductor track 34. A capacitance of the capacitor 28 can be designed or selected such that the capacitance of the capacitor 28 specifies a threshold value for triggering the pressure relief unit 22.

[0098] The circuit 29 further comprises a switching element 38, which can be controlled by the control element 35. The switching element 38 is a transistor, in particular an npn transistor (negative-positive-negative). The switching element 38 can also be a relay. The switching element 38 has a base 39, an emitter 40, and a collector 41. A control output 42 of the control element 35 is connected to the base 39. The emitter 40 is connected via a sixth conductor track 43 to the pyrotechnic charge 31, which is additionally connected to the first conductor track 32. The collector 41 is connected to the second conductor track 33.

[0099] The functionality of the pressure relief device 24 is explained below. One or more fire sources 44, only one of which is provided with a reference symbol in Fig. 8, introduce heat Q into the sensor fiber 23. This creates an electrical voltage between the electrodes 25, 26. The capacitor 28 acts as an energy storage device, which is charged with electrical energy using the sensor fiber 23. The capacitor 28 stores electrical energy until sufficient electrical energy is available to trigger the pressure relief unit 22. The voltage across the capacitor 28, which is detected using the control element 35, is used as an indicative variable for the charging of the capacitor 28.

[0100] If the capacitor 28 is sufficiently charged to generate the pyrotechnic charge

[0101] To ignite the 31, the control element 35 energizes the base 39 of the switching element 38 via the control output 42. The point in time at which the control element 35 energizes the base 39 can be influenced by the design of the control element 35. For example, a certain voltage can be specified as the triggering criterion, which must be present at least at the capacitor 28.

[0102] When the base 39 is energized, the switching element 38 switches such that, in particular, a glow bridge igniting the pyrotechnic charge 31 is energized by the capacitor 28 via the conductor tracks 32, 33, 34, 43. The pyrotechnic charge 31 is ignited, and the valve 30 opens to release the hydrogen H2 from the compressed gas storage container 7B. When the pyrotechnic charge 31 is ignited, it generates a blast or pressure wave 45. With the aid of the pressure wave 45, a component of the valve 30, for example, a valve body or a valve tappet, can be moved to open it.

[0103] Fig. 8 shows a schematic side view of another embodiment of a compressed gas storage container 7C.

[0104] The compressed gas storage container 7C differs from the compressed gas storage container 7B only in that it is provided not with a single sensor fiber 23, but with a plurality of short sensor fibers 23A, 23B, two of which are shown in Fig. 8. All sensor fibers 23A, 23B supply current to a common capacitor 28. This can accelerate the charging of the capacitor 28. This increases the sensitivity of the pressure relief device 24. The sensitivity can be adjusted via the length and / or the number of sensor fibers 23A, 23B.

[0105] The sensor fibers 23A, 23B can be shorter than the previously mentioned sensor fiber 23. The number of sensor fibers 23A, 23B is arbitrary. The sensor fibers 23A, 23B can cross each other. This results in a network-like arrangement of the sensor fibers 23A, 23B. However, such an arrangement of the sensor fibers 23A, 23B is optional. Any number of sensor fibers 23A, 23B of different lengths can be provided.

[0106] Although the present invention has been described using exemplary embodiments, it can be modified in many ways.

[0107] LIST OF REFERENCE SYMBOLS Vehicle Body Vehicle interior Environment Wheel Wheel Pressure gas storage vessel A Pressure gas storage vessel B Pressure gas storage vessel C Pressure gas storage vessel Consumer Wall 0 Receptacle area 1 Central axis 2 Base section 3 Wall end section 4 Wall end section 5 Sheath 6 Outside 7 Inside 8 Lining 9 Outside 0 Inside 1 Inlet nozzle 2 Pressure relief unit 3 Sensor fiber 3A Sensor fiber 3B Sensor fiber 24 Pressure relief device

[0108] 25 Electrode

[0109] 26 Electrode

[0110] 27 Materials

[0111] 28 Capacitor

[0112] 29 Circuit

[0113] 30 valve

[0114] 31 pyrotechnic charge

[0115] 32 conductor tracks

[0116] 33 Conductor track

[0117] 34 conductor track

[0118] 35 Control element

[0119] 36 conductor track

[0120] 37 Conductor track

[0121] 38 switching element

[0122] 39 Base

[0123] 40 emitters

[0124] 41 Collector

[0125] 42 Control output

[0126] 43 Conductor track

[0127] 44 Fire source

[0128] 45 pressure wave

[0129] H2 gas / hydrogen

[0130] L longitudinal direction

[0131] Q Heat

[0132] R Radial direction x x- direction y y- direction z z- direction

Claims

PATENT CLAIMS 1. Compressed gas storage container (7, 7A, 7B, 7C) for the pressurized storage of a gas (H2), in particular hydrogen, with a wall (9) which encloses a receiving area (10) for receiving the gas (H2), a pressure relief unit (22) for blowing off the gas (H2) from the receiving area (10), and a pyroelectric sensor fiber (23, 23A, 23B) which is designed to trigger the pressure relief unit (22) in the event of a fire-related introduction of heat (Q) into the wall (9) in order to blow off the gas (H2) from the receiving area (10).

2. Compressed gas storage container according to claim 1, characterized in that the pressure relief unit (22) has a valve (30) for blowing off the gas (H2) from the receiving area (10) and a pyrotechnic charge (31), wherein the pyroelectric sensor fiber (23, 23A, 23B) ignites the pyrotechnic charge (31) to open the valve (30).

3. Compressed gas storage container according to claim 1 or 2, characterized in that the pyroelectric sensor fiber (23, 23A, 23B) has a first electrode (25), a second electrode (26) and a pyroelectric material (27) arranged between the first electrode (25) and the second electrode (26).

4. Compressed gas storage container according to one of claims 1 - 3, characterized in that the pyroelectric sensor fiber (23, 23A, 23B) is arranged in or on the wall (9).

5. Compressed gas storage container according to claim 4, characterized in that the pyroelectric sensor fiber (23, 23A, 23B) is embedded at least in sections in the wall (9).

6. Compressed gas storage container according to one of claims 1 - 5, characterized in that the pyroelectric sensor fiber (23, 23A, 23B) winds helically around the wall (9) when viewed along a longitudinal direction (L) of the compressed gas storage container (7, 7A, 7B, 7C).

7. Compressed gas storage container according to one of claims 1 - 6, characterized by a plurality of pyroelectric sensor fibers (23A, 23B), wherein all of the plurality of pyroelectric sensor fibers (23A, 23B) are jointly assigned to the pressure relief unit (22).

8. Compressed gas storage container according to claim 7, characterized in that the plurality of pyroelectric sensor fibers (23A, 23B) are arranged parallel to one another and / or cross one another.

9. Compressed gas storage container according to one of claims 1 - 8, characterized by a capacitor (28) for storing electrical energy generated by means of the pyroelectric sensor fiber (23, 23A, 23B).

10. Compressed gas storage container according to claim 9, characterized by an electrical circuit (29) comprising the capacitor (28) and the pyroelectric sensor fiber (23, 23A, 23B), wherein the electrical circuit (29) is configured to release the electrical energy stored in the capacitor (28) as a function of a variable indicative of a charging of the capacitor (28) in order to trigger the pressure relief unit (22).

11. Compressed gas storage container according to claim 10, characterized in that the electrical circuit (29) has a control element (35) which detects the indicative variable, and a switching element (38) which can be controlled by the control element (35) as a function of the indicative variable in order to release the electrical energy stored in the capacitor (28) to trigger the pressure relief unit (22).

12. Compressed gas storage container according to claim 11, characterized in that the control element (35) is connected in parallel to the capacitor (28), wherein the switching element (38) is connected in parallel to the capacitor (28), and wherein the control element (35) controls the switching element (38) by means of a control output (42).

13. Compressed gas storage container according to claim 11 or 12, characterized in that the control element (35) is a voltmeter, wherein the switching element (38) is a transistor.

14. Compressed gas storage container according to one of claims 1 - 13, characterized in that the pressure relief unit (22) is attached to a dome-shaped wall end section (13, 14) of the wall (9).

15. Vehicle (1), in particular a motor vehicle, with at least one compressed gas storage container (7, 7A, 7B, 7C) according to one of claims 1 - 14.

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