COMPRESSED GAS STORAGE UNIT, AND VEHICLE COMPRISING A COMPRESSED GAS STORAGE UNIT

Abstract

The invention relates to a compressed gas storage unit (1) for mobile applications, in particular for storing hydrogen on board a vehicle, comprising at least one metal storage housing (2) which delimits a storage volume (3) that can be filled with compressed gas, as well as at least one temperature- and/or pressure-sensitive overload valve (4) arranged on the storage housing (2). According to the invention, the storage housing (2) or the compresses gas storage unit (1) is surrounded by a heat protection shield (5) at least in regions, preferably releasing the at least one overload valve (4). The invention also relates to a vehicle comprising a compressed gas storage unit (1) according to the invention for storing hydrogen.

Claims

1. A compressed gas storage unit (1) for mobile applications, comprising at least one metal storage housing (2) which delimits a storage volume (3) which can be filled with compressed gas, and at least one temperature- and/or pressure-sensitive overload valve (4) arranged on the storage housing (2), wherein the storage housing (2) or the compressed gas storage unit (1) is surrounded at least in some regions by a heat shield (5).

2. The compressed gas storage unit (1) as claimed in claim 1, wherein the heat shield (5) is or comprises a coating, a cladding and/or an enclosure.

3. The compressed gas storage unit (1) as claimed in claim 1, wherein the heat shield (5) is made at least in part of a non-metallic material.

4. The compressed gas storage unit (1) as claimed in claim 1, wherein the storage housing (2) is substantially hollow cylindrical and/or has at least one dome-shaped end portion (6) in a region of which the overload valve (4) is arranged.

5. The compressed gas storage unit (1) as claimed in claim 1, wherein the heat shield (5) is arranged in an outer circumferential region of the storage housing (2) and extends over an angle range of at least 45°.

6. The compressed gas storage unit (1) as claimed in claim 1, wherein the heat shield (5) is arranged in a region of an end face of the storage housing (2).

7. The compressed gas storage unit (1) as claimed in claim 1, wherein the heat shield (5) has an inner contour which is adapted to an outer contour of the storage housing (2).

8. The compressed gas storage unit (1) as claimed in claim 1, wherein the compressed gas storage unit (1) comprises a plurality of storage housings (2), each of which is equipped with a heat shield (5).

9. A vehicle having a compressed gas storage unit (1) as claimed in claim 1 for the storage of hydrogen.

10. The vehicle as claimed in claim 9, wherein the heat shield (5) of the compressed gas storage unit (1) is arranged at least in a region of an outer surface of the compressed gas storage unit (1) that faces a heat source of the vehicle.

11. The compressed gas storage unit (1) as claimed in claim 1, wherein the compressed gas storage unit (1) stores hydrogen on board a vehicle.

12. The compressed gas storage unit (1) as claimed in claim 1, wherein the at least one overload valve (4) is not surrounded by the heat shield (5).

13. The compressed gas storage unit (1) as claimed in claim 3, wherein the non-metallic material has a temperature conductivity (a)<1 mm.sup.2/s.

14. The compressed gas storage unit (1) as claimed in claim 5, wherein, the heat shield extends over an angle range of at least 90°.

15. The compressed gas storage unit (1) as claimed in claim 14, wherein, the heat shield extends over an angle range of at least 120°.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Preferred embodiments of the invention will be explained in greater detail hereinbelow with reference to the accompanying drawings, in which:

[0030] FIG. 1 is a schematic longitudinal section through a first compressed gas storage unit according to the invention,

[0031] FIG. 2 is a schematic longitudinal section through a second compressed gas storage unit according to the invention,

[0032] FIG. 3 is a schematic longitudinal section through a third compressed gas storage unit according to the invention,

[0033] FIG. 4 is a schematic longitudinal section through a fourth compressed gas storage unit according to the invention,

[0034] FIG. 5 is a schematic longitudinal section through a fifth compressed gas storage unit according to the invention,

[0035] FIG. 6 is a schematic longitudinal section through a sixth compressed gas storage unit according to the invention,

[0036] FIG. 7 is a schematic longitudinal section through a seventh compressed gas storage unit according to the invention,

[0037] FIG. 8 is a schematic longitudinal section through a compressed gas storage unit known from the prior art,

[0038] FIG. 9 is a diagram for graphically depicting the temperature profile in the wall of a storage housing of a compressed gas storage unit known from the prior art, and

[0039] FIG. 10 is a diagram for graphically depicting the temperature profile in the wall of a storage housing of a compressed gas storage unit according to the invention.

DETAILED DESCRIPTION

[0040] A first compressed gas storage unit 1 according to the invention is shown in FIG. 1. It comprises a hollow cylindrical metal storage housing 2 which has a dome-shaped end portion 6 at each of its ends. An overload valve 4 is in each case arranged centrally in relation to the end portions 6.

[0041] The hollow cylindrical metal storage housing 2 delimits a storage volume 3 for holding a gas under pressure, in the present case hydrogen. Because the pressure in the storage volume 3 can be up to 700 bar, it is important to prevent or at least significantly reduce a temperature rise caused by an input of heat from outside, and a further pressure rise associated therewith. The storage housing 2 shown is therefore surrounded completely by a heat shield 5 in the form of a coating, while the two overload valves 4 are left free. The coating consists of a material which has a significantly reduced thermal conductivity compared to the metal of the storage housing 2, so that the temperature conductivity is lowered. Consequently, the storage housing 2 heats up to a significantly lesser extent as a result of an input of heat from outside.

[0042] FIG. 2 shows a further compressed gas storage unit 1 according to the invention, which differs from FIG. 1 in that the heat shield 5 is formed only partially. It leaves not only the two overload valves 4 but also the two end portions 6 free.

[0043] Because the compressed gas storage unit 1 may also have only one overload valve 4, it is possible in this case to omit the heat shield 5 only in the region of the end portion 6 in which the overload valve 4 is optionally arranged. This embodiment is shown by way of example in FIG. 3.

[0044] FIG. 4 shows an embodiment of a compressed gas storage unit 1 according to the invention in which the heat shield 5 is formed by a cladding of the storage housing 2. The cladding encloses the storage housing completely—while leaving free two overload valves 4 each arranged at an end face.

[0045] FIG. 5 shows a variant with only one overload valve 4 arranged at an end face and an enclosure as the heat shield 5. Analogously to the exemplary embodiment of FIG. 3, the enclosure is omitted in the end portion 6 in which the overload valve 4 is arranged.

[0046] As is shown in FIGS. 6 and 7, the enclosure can be further reduced so that only the regions that face a heat source in the concrete application are protected from an input of heat from outside.

[0047] FIG. 8 shows a conventional compressed gas container having a hollow cylindrical metal storage housing 2 and two overload valves 4 each arranged at an end face. Because of the absence of a heat shield 5, the compressed gas in the interior of the storage housing 2 can heat up as a result of an input of heat from outside and lead to a pressure rise, which is associated with an increased risk of bursting.

[0048] FIG. 9 shows by way of example the temperature profile in the wall of a storage housing 2 configured according to FIG. 8. The temperature T.sub.A at the outside surface A.sub.A falls only slightly across the thickness of the wall to the inside surface A.sub.I, so that the compressed gas in the storage volume 3 heats up considerably. The temperature is therefore only just below the maximum permissible temperature T.sub.max.

[0049] In a compressed gas storage unit 1 according to the invention, a significant reduction in heating can be achieved with the aid of the heat shield 5. This is shown by way of example in FIG. 10. Owing to the poor thermal conductivity of the material of the heat shield 5, the temperature T.sub.A falls to a value below the maximum permissible temperature T.sub.max even outside the storage housing 2. The temperature measured at the outside surface A.sub.A2 of the storage housing 2 is thus significantly below the temperature T.sub.A at the outside surface A.sub.A1 of the heat shield 5. Because a further temperature drop is achieved across the wall of the storage housing 2, the temperature in the interior of the storage housing 2 is significantly below T.sub.max.