DE102021124236A1 - Pressure vessel, pressure vessel system, automotive vehicle and method of forming ribs - Google Patents

Abstract

According to the invention, the technology disclosed here relates to a pressure vessel 10 for storing gaseous fuel, having a vessel wall 20 which encloses an interior space 15, with one or more ribs 30, 40 being formed on the vessel wall 20. According to the invention, the technology disclosed here also relates to a pressure vessel system 5 with at least two such pressure vessels 10, a motor vehicle and a method for forming ribs 30, 40 on a vessel wall 20 of a pressure vessel 10.

Description

The technology disclosed herein relates to a pressure vessel for storing gaseous fuel, a pressure vessel system having two or more such pressure vessels, an automotive vehicle, and a method of forming ribs on a vessel wall of a pressure vessel.

Pressure vessels are typically used to provide gaseous fuel in mobile or stationary units such as automobiles. A gas-powered internal combustion engine or a fuel cell, for example, can be driven with the gaseous fuel.

It is a preferred object of the technology disclosed herein to mitigate or obviate at least one disadvantage of a previously known solution or to propose an alternative solution. In particular, it is a preferred object of the technology disclosed herein to provide a pressure vessel with improved stability. Other preferred objects may arise from the beneficial effects of the technology disclosed herein. The objects are solved by the subject matter of the independent patent claims. The dependent claims represent preferred embodiments.

The technology disclosed herein relates to a pressure vessel for storing gaseous fuel. The pressure vessel includes a vessel wall that encloses an interior space. One or more ribs are formed on the container wall.

The stability of the pressure vessel can be increased by means of such ribs. In particular, the ribs can be used specifically as structural elements to improve the rigidity of the pressure vessel, for example to design it for higher pressures or special requirements. Other advantageous configurations are also possible, which are described in more detail below, for example.

A container wall can in particular be understood to mean a wall which encloses the interior. The gaseous fuel is typically stored under pressure and/or at particularly low temperatures in the interior. Ribs are to be understood in particular as projections which protrude from a surrounding surface. These are typically visually recognizable as such and can be distinguished due to their protruding character. If a rib cannot be precisely defined due to the smooth transitions of a structure, this does not negate its properties as a rib. Rather, a suitable definition can be selected, for example a minimum elevation over a surrounding area or a surrounding depression.

According to one embodiment, one, some or all of the ribs are formed from the same material as the container wall. In particular, this permits simple production and a stable material connection between the ribs and the other parts of the container wall.

According to one embodiment, one, some or all of the ribs are formed from a different material than the container wall. As a result, the ribs can be given special properties by selecting a suitable material.

The designs of the ribs of the same material as the container wall and of a different material than the container wall can also be combined, so that for example some ribs can be made of the same material and some ribs can be made of a different material. As a result, specific properties can be achieved through material combinations.

According to one embodiment, one, some or all of the ribs are made of metal and/or carbon fiber reinforced plastic. Such materials have proven advantageous because of their strength. However, other materials can also be used.

In particular, delimiting planes of some or all of the ribs can be aligned parallel to one another. This allows for a simple design and an advantageous and uniform increase in stability.

In particular, the ribs can be of the same width and/or have the same distances to each immediately adjacent ribs. Ribs at the axial end can in particular only have one adjacent rib, ie on one side. This allows for a simple design with an even effect on stability. However, non-uniform designs are also possible.

Dimensions are given below that have proven to be advantageous for typical purposes. In particular, this applies to use in an installation space below a passenger compartment of a motor vehicle, with such an installation space typically being relatively flat and thus suitable for the installation of a plurality of pressure vessels next to one another. These pressure vessels can be combined to form a pressure vessel system, for example, as is described further below. a sun ches pressure vessel system can in particular have a common connection line for all pressure vessels, which in particular can allow pressure equalization between the pressure vessels at any time.

A wall thickness of the pressure vessel can be at least 5.4 mm and/or at most 7.5 mm, in particular between the ribs. This typically refers to areas lying axially between the ribs. However, wall thickness is typically measured radially.

In particular, the axial length of a pressure vessel can be at least 1,500 mm and/or at most 2,000 mm. A diameter of a pressure vessel can in particular be at least 120 mm and/or at most 175 mm.

A height of the ribs relative to the immediately surrounding container wall can be in particular at least 1 mm, at least 2 mm, at least 4 mm or at least 6 mm. In particular, it can be at most 2 mm, at most 3 mm, at most 4 mm, at most 6 mm or at most 7 mm. The height can be measured in particular as a projection over the directly adjacent container wall. This can apply to both the inside and the outside.

A width of the ribs can in particular be at least 20 mm, at least 25 mm, at least 30 mm or at least 35 mm. In particular, it can be at most 25 mm, at most 30 mm, at most 35 mm or at most 40 mm. The width can in particular be measured axially, ie along a longitudinal direction of the pressure vessel.

A distance between directly adjacent ribs can in particular be at least 10 mm or at least 15 mm. In particular, it can be at most 15 mm or at most 20 mm. A distance can in particular be measured axially, ie along a longitudinal direction of the pressure vessel.

According to a development, it is provided that one or more circumferential reinforcement layers are formed between immediately adjacent outer ribs. These can be located in particular in the spaces between the ribs. You can in particular fill the respective gap axially. In particular, the ribs can protrude further compared to the reinforcement layers. As a result, they can provide mechanical protection for the reinforcement layers.

The reinforcement layers can in particular be made of carbon fiber reinforced plastic. This achieves an advantageous additional stability. In particular, the stability can be achieved with less material than when using steel alone. Carbon fiber reinforced plastic can also be referred to as CFRP.

The reinforcement layers can in particular be unidirectional. In particular, they can extend along a circumference. This achieves an advantageous absorption of outwardly directed forces.

A height of the ribs can in particular be at least 20% and/or at most 30% greater than a height of the reinforcement layers. In particular, a height can be measured relative to a surrounding (in the case of the ribs) or underlying (in the case of the reinforcement layers) container wall. In particular, the height of the ribs can be 25% higher than the height of the reinforcement layers. This allows for the fact that the strength of CFRP material can be around 25% higher than that of steel, for example. For example, the strength of steel can be 2,000 MPa and the strength of CFRP material can be 2,500 MPa.

According to an advantageous embodiment, a barrier layer is formed between the container wall and the interior. This barrier layer can contribute in particular to reducing or preventing the diffusion of gaseous fuel, in particular hydrogen, into the container wall. This can have a beneficial effect on the long-term properties of the container wall.

In particular, the barrier layer can completely line the inside of the container wall. As a result, a complete protection of the container wall is achieved by the barrier layer. The barrier layer can also line at least 70%, at least 80% or at least 90% of the container wall on the inside.

The barrier layer can be formed in particular from ethylene-vinyl alcohol copolymer (EVOH). This has proven to be particularly advantageous for preventing hydrogen from diffusing into the container wall. However, other materials can also be used.

The barrier layer can advantageously have an ethylene content of between 20 mol % and 28 mol %, or particularly preferably 24 mol %. Such ethylene contents ensure good manufacturability and at the same time good under binding of hydrogen indiffusion. However, other values can also be used. In particular, these values are preferred when the ethylene-vinyl alcohol copolymer barrier layer is used.

The barrier layer can in particular have a thickness between 80 μm and 250 μm. Such values have proven advantageous. For example, a thickness of 200 □m can be aimed at in order to achieve a thickness of 130 □m everywhere, taking unevenness into account.

Furthermore, a metal layer can advantageously be arranged between the barrier layer and the container wall. This can also contribute to preventing hydrogen permeation.

The metal layer can be made of copper or a copper alloy, for example. It can also be made of another metal or a metal alloy. In particular, it can be combined with a barrier layer made of plastic, for example as mentioned above.

In particular, when using a barrier layer and/or metal layer, it can be provided that all the ribs on the container wall are formed on the outside. This combination has proven to be particularly advantageous with regard to the durability of the container wall, especially when using hydrogen as the gaseous fuel. The diffusion of hydrogen is effectively prevented and at the same time a better release of hydrogen that has nevertheless penetrated is achieved via the outer surface, which has been enlarged by means of the ribs on the outside.

Furthermore, an anti-corrosion layer can be applied to the outside of the container wall. This can prevent or slow down any corrosion.

The anti-corrosion layer can be formed in particular from a zinc-nickel alloy. This material has proven advantageous for typical applications. In particular, it allows hydrogen to diffuse out to the environment. However, other materials can also be used.

The corrosion layer is particularly advantageous when the pressure vessel is used without a watertight housing.
According to one embodiment, one, some or all of the ribs of the container wall are formed on the inside. The ribs are thus formed towards the interior and in particular come into contact with a gaseous fuel stored in the pressure vessel.

According to one embodiment, one, some or all of the ribs are formed on the outside of the container wall. These fins typically do not contact the gaseous fuel stored in the cabin, but do contact a surrounding atmosphere.

Inside and outside ribs can also be combined with each other. In particular, these can be formed in alternation. This can mean, in particular, that ribs on the outside and on the inside alternate continuously along a longitudinal axis of the pressure vessel. In particular, the outside and inside ribs can follow one another directly along the longitudinal axis. However, they can also have certain distances from one another.

The technology disclosed herein also relates to a pressure vessel system. This includes two or more pressure vessels as described herein. Ribs of one, some or all of the pressure vessels engage in spaces between ribs of one or more immediately adjacent pressure vessels.

A number of advantages can be achieved by such a pressure vessel system. In particular, space can be saved by the ribs engaging in intermediate spaces. By suitably clamping the ribs against one another, a stable position of the pressure vessels relative to one another can be established. Alternatively or additionally, a holding device can also be present, which brings about such a constellation.

The longitudinal axes of the pressure vessels can in particular be aligned parallel to one another. This enables a simple design which is particularly suitable, for example, for installation in an underfloor area of a motor vehicle.

The ribs of immediately adjacent pressure vessels can in particular be designed without any axial offset relative to one another relative to at least one longitudinal end of the pressure vessel. Directly adjacent pressure vessels can in particular be arranged axially offset from one another. This results in an embodiment in which identical pressure vessels can be used, with a slight axial displacement of the pressure vessels being accepted. Outside of the ribs, there may also be differences between the pressure vessels, which does not detract from the functionality relevant here. An embodiment of the ribs without an axial offset relative to one another relative to at least one longitudinal end of the pressure vessel can be understood in particular that, starting from a respective longitudinal end of the at least two pressure vessels under consideration, the ribs are the same distance from this longitudinal end. This is then taken into account in the pressure vessel system by means of an axial offset of the pressure vessels relative to one another.

According to one embodiment, the ribs of immediately adjacent pressure vessels are offset axially with respect to the immediately adjacent pressure vessel. Directly adjacent pressure vessels are arranged axially non-offset to one another, in particular with respect to one longitudinal end or both longitudinal ends. As a result, it can be achieved that the pressure vessels extend uniformly along their respective longitudinal direction, that is to say they do not differ from neighboring pressure vessels in this respect. This can enable better utilization of installation space and/or better load distribution. Typically, two different pressure vessels are required for such an embodiment, so that they can be used alternately and respective ribs can engage in spaces between adjacent pressure vessels.

In ribs of directly adjacent pressure vessels, in particular, aligned through-holes can be formed, through which a fastening means runs. As a result, the security of the pressure vessel system against any slipping can be increased. For example, the fastening means can be a wire which can run through the through-holes.

Ribs of directly adjacent pressure vessels can in particular be connected to one another in a non-positive manner. This achieves a simple and reliable fastening of the pressure vessels to one another.

In particular, the pressure vessels can be connected by a common connection line, in which case pressure equalization between the pressure vessels is never impaired by valves. The connection line can have a tank shut-off valve, for example, with which all pressure vessels can be shut off or released at the same time. The shared connection line ensures that pressure can be equalized at any time between the pressure vessels. As a result, they have the same internal pressure. During operation, with fluctuating pressures, this means that the pressure vessels always expand at the same rate. And it means that the interlocking ribs always maintain the same gap to the neighboring rib.

The technology disclosed here also relates to a motor vehicle with a pressure vessel system as described herein, the pressure vessel system being installed in an underfloor installation space of the motor vehicle. With regard to the pressure vessel system, all variants described herein can be used. The installation of such a pressure vessel system in an underfloor installation space of a motor vehicle brings with it the particular advantage that the pressure vessel system described herein is particularly well adapted to a flat design and is very compact and easy to handle. An underfloor installation space is typically an installation space below the passenger compartment of a motor vehicle, which is typically relatively flat.

The technology disclosed herein also relates to a method of forming ribs from a vessel wall of a pressure vessel. Three different procedures are described below for this procedure.

According to one embodiment, the ribs are produced separately and the ribs are applied to the container wall in a non-positive manner by means of cold forming. As a result, the ribs can be manufactured separately, for example from a different material, or from the same material as the container wall.

According to one embodiment, the pressure vessel is subjected to an internal pressure, with the pressure vessel being cold-formed to form the ribs. The well-known process of cold forming can be used for this purpose. This can be used in particular when the ribs are to be formed from the same material as the container wall.

According to one embodiment, the ribs are produced separately and the ribs are thermally shrunk onto the container wall. This allows the ribs to be manufactured separately, for example from a different material than the container wall, or from the same material. Shrinking is a reliable technology for connecting the ribs to the container wall.

The method can also include a step of introducing a barrier layer on the inside of the container wall. This can be carried out in particular by rotomoulding, blow molding or extrusion. Such procedures have proven to be advantageous for the introduction of a barrier layer. The barrier layer can be formed in particular as described above.

A rotomoulding process can be carried out in particular at a temperature of 190.degree. C. to 270.degree. This melts a suitable material such as EVOH but does not degrade its properties.

The tightness of a barrier layer can, for example, be checked after production using an endoscope.

A pressure vessel system can be understood in particular as a fuel supply system which contains a number of pressure vessels and associated valves such as shut-off valves, check valves and thermal pressure relief devices which are used to separate and store gaseous fuel, which is typically under high pressure and/or is stored particularly cold, in a vehicle are required.

The pressure vessel system can be used, for example, for a motor vehicle (for example passenger cars, motorcycles, commercial vehicles). The pressure vessel system serves in particular to store fuel which is gaseous under ambient conditions. The pressure vessel system can be used, for example, in a motor vehicle that is operated with compressed (also called Compressed Natural Gas or CNG) or liquefied (also called Liquid Natural Gas or LNG) natural gas or with hydrogen. The pressure vessel system is typically fluidly connected to at least one energy converter that is configured to convert the chemical energy of the fuel into other forms of energy.

Such a pressure vessel system typically includes at least one pressure vessel, in particular a composite overwrapped pressure vessel. The pressure vessel can be, for example, a cryogenic pressure vessel or a high-pressure gas vessel.

High-pressure gas tanks are designed to permanently store fuel at ambient temperatures at a nominal operating pressure (also known as nominal working pressure or NWP) of at least 350 bar overpressure (= excess pressure compared to atmospheric pressure) or at least 700 bar overpressure. A cryogenic pressure vessel is suitable for storing the fuel at the aforementioned operating pressures even at temperatures that are significantly (for example more than 50 K or more than 100 K) below the operating temperature of the motor vehicle.

The pressure vessels can in particular have circular or oval cross sections. In particular, they can have a common shut-off valve or they can have separate shut-off valves.

The tank shut-off valve is typically a valve whose inlet pressure (substantially) corresponds to the tank pressure. The tank shut-off valve is in particular a controllable or regulatable and in particular normally closed valve. In Commission Regulation (EU) No. 406/2010 of April 26, 2010 implementing Regulation (EC) No. 79/2009 of the European Parliament and of the Council on the type approval of hydrogen-powered motor vehicles, such a tank shut-off valve is also used as the first valve designated.

In other words, steel tanks, for example, are usually designed as smooth cylinders. Ribs can be provided on the cylindrical tank wall. The ribs can be installed inside the tank or on the outside surface. In particular, they act as reinforcement elements and allow to reduce the wall thickness (excluding ribs). This can be confirmed by FEM simulations.

For example, a steel tank can have a wall thickness of 4.5 mm (excluding ribs). This can absorb the same maximum tension on the inner surface as a ribless tank with a wall thickness of 5 mm. The ribs can be formed inside, outside or both inside and outside.

The ribs can be made of metal or CFRP (carbon fiber reinforced plastic), for example. Especially for the outer ribs, CFRP circumferential windings can be used to advantage. A high fiber volume content can be achieved there and the carbon fibers are loaded in the tensile direction where they have their best strength properties. Outer metal ribs can be manufactured as rings and connected to the tank from the outside using cold forming. Internal pressure can also be applied to the tank so that it expands plastically and is thus cold-formed from the inside. It is also conceivable that the rings are thermally shrunk on. Using these manufacturing methods, it is also possible to introduce a slight elastic prestress into the tank wall, which counteracts the internal pressure load and thus improves operational stability. Several identical tanks can be arranged in an underfloor tank system in such a way that the ribs are offset to one another. Such an arrangement has the advantage that the distance between the central axes of the tanks is smaller than when tanks without ribs are used. If equal tanks are used, they can be longitudinally offset by the rib spacing. Alternatively, use two different tanks whose ribs are offset. This can simplify neck mounting, for example.

The outer ribs can also be used to fasten the tanks together. A metal wire can be inserted into holes in the ribs. Such a fastening has a remaining rotational degree of freedom, which can be supplemented in other ways with a moment support. As an alternative to this, the ribs can be connected to one another in a non-positive manner, in which case they no longer have the rotational degree of freedom.

A nominal pressure of a pressure vessel can be 700 bar, for example.

• - Zugfestigkeit von mindestens 1.500 MPa, vorzugsweise mindestens 1.700 MPa, besonders vorzugsweise mindestens 1.900 MPa,
• - und/oder 0,2 % Streckgrenze von mindestens 1.100 MPa, vorzugsweise mindestens 1.300 MPa, besonders vorzugsweise mindestens 1.500 MPa,
• - und/oder Bruchdehnung von höchstens 10 %, vorzugsweise höchstens 8 %, besonders vorzugsweise höchstens 6 %.

For example, the material of the pressure vessel can have the following properties after heat treatment:

• - Tensile strength of at least 1,500 MPa, preferably at least 1,700 MPa, particularly preferably at least 1,900 MPa,
• - and/or 0.2% yield strength of at least 1,100 MPa, preferably at least 1,300 MPa, particularly preferably at least 1,500 MPa,
• - and/or elongation at break of at most 10%, preferably at most 8%, particularly preferably at most 6%.

• 1: einen Druckbehälter gemäß einem ersten Ausführungsbeispiel,
• 2: einen Druckbehälter gemäß einem zweiten Ausführungsbeispiel,
• 3: einen Druckbehälter gemäß einem dritten Ausführungsbeispiel,
• 4: ein Druckbehältersystem gemäß einem ersten Ausführungsbeispiel,
• 5: ein Druckbehältersystem gemäß einem zweiten Ausführungsbeispiel,
• 6: ein Druckbehältersystem gemäß einem dritten Ausführungsbeispiel,
• 7: das Druckbehältersystem von 6 in einer anderen Ansicht, und
• 8: einen Druckbehälter gemäß einem vierten Ausführungsbeispiel.

The technology disclosed here will now be described with reference to the figures. show:

• 1 : a pressure vessel according to a first embodiment,
• 2 : a pressure vessel according to a second embodiment,
• 3 : a pressure vessel according to a third embodiment,
• 4 : a pressure vessel system according to a first embodiment,
• 5 : a pressure vessel system according to a second embodiment,
• 6 : a pressure vessel system according to a third embodiment,
• 7 : the pressure vessel system from 6 in another view, and
• 8th : a pressure vessel according to a fourth embodiment.

1 shows a pressure vessel 10 purely schematically. This has a vessel wall 20 which encloses an interior space 15 . The container wall 20 has a first connection 25 and a second connection 26 through which the interior 15 can be filled and emptied.

In the present case, the pressure vessel 10 is designed as an elongate vessel with a circular cross section. The cross section is perpendicular to the plane of the paper 1 to see.

A plurality of ribs 30 are formed on the container wall 20 on the outside. These ribs 30 protrude outwards. They run in the cross section already mentioned, are parallel to one another, have the same length and have identical sections to one another. The pressure vessel 10 is reinforced by means of these external ribs 30 so that, for example, a greater internal pressure can be used.

2 shows purely schematically a pressure vessel 10 according to a second embodiment. In the following, essentially only the differences from the first exemplary embodiment will be discussed. Regarding the other elements, refer to the description of 1 referred. This also applies to the figures described below.

In the pressure vessel 10 according to the second embodiment, instead of the outside ribs 30, inside ribs 40 are formed. These also run parallel to each other in respective planes transverse to the plane of the paper 2 , These also have identical dimensions in the longitudinal direction of the pressure vessel 10 and identical distances from one another. A reinforcement of the pressure vessel 10 can thereby be achieved in a similar manner.

3 shows a pressure vessel 10 according to a third embodiment. Both outside ribs 30 and inside ribs 40 are formed. As shown, the ribs 30, 40 alternate axially with one another such that an outboard rib 30 always immediately follows an inboard rib 40. This can also advantageously increase the strength. Alternatively, it would also be possible, for example, to provide axial distances between the inside ribs 40 and the outside ribs 30 .

4 shows a pressure vessel system 5 according to a first embodiment. A total of four pressure vessels 10 are shown, with respect to their description 1 be referred.

As shown, the pressure vessels 10 are arranged so that respective outside ribs 30 fit into respective spaces 35 between outside ribs 30 of the respective adjacent pressure vessels holder 10 engage. Since the pressure vessels 10 are all identical to one another, this requires a slight offset along the longitudinal directions of the pressure vessels 10. This means that identical pressure vessels 10 can be used. The space requirement can be reduced by the ribs 30 engaging in intermediate spaces 35 and stability can be achieved in that the ribs 30 are positively clamped with the ribs 30 in contact with them of a respective adjacent pressure vessel 10 . As a result, a certain non-positive connection can also be built up, through which the pressure vessel system 5 is stabilized.

5 shows a pressure vessel system 5 purely schematically according to a second embodiment. In contrast to running 4 two different types of pressure vessels 10 are used, namely type A and type B. These are in 5 drawn. The types of pressure vessels 10 differ only in that the outside ribs 30 are offset from one another in such a way that the otherwise identical pressure vessels 10 can be arranged directly adjacent to one another with respect to their longitudinal directions without any axial offset and while nevertheless locating respective outside ribs 30 in respective intermediate spaces 35 adjacent pressure vessel 10 intervene. In particular, this permits simpler neck mounting, that is to say mounting of the pressure vessels 10 at their respective longitudinal ends.

The pressure vessel 10 are in the execution of 5 connected by a common connection line 7. This enables pressure equalization between the pressure vessels 10 at any time, which is not affected by valves. As a result, the pressure vessels 10 have the same internal pressure at all times. In the event of pressure fluctuations, they expand and contract evenly. Opposite the connection line 7, the pressure vessels 10 can be individually closed, for example, or they can be connected in some other way.

6 shows a modification of the execution of 5 to the extent that in the outside ribs 30 there are respective aligned through bores 32 through which a fastening means 6 in the form of an elongate wire runs. The two pressure vessels 10 can be positively connected to one another by means of these fastening means 6, so that it becomes impossible to remove them from one another without first loosening the fastening means 6. With this type of connection, a degree of freedom typically remains in the form of a rotation about the fastening means 6. This degree of freedom can be compensated for, for example, by suitable support elements in such a way that the pressure vessels 10 have a defined position relative to one another.

7 shows the pressure vessel system 5 of FIG 6 in a schematic cross-sectional view. It can be seen here that the through bores 32 are formed on the outside in a respective outside rib 30 . The ribs 30 engage in the respective intermediate spaces 35 of the adjacent pressure vessels 10 and the through bores 32 are aligned, so that the fastening means 6 in the form of an elongate wire can be pushed through without any problems.

8th shows a pressure vessel 10 according to a fourth embodiment. Circumferential reinforcing layers 37 made of carbon fiber reinforced plastic (CFRP) are arranged between the ribs 30 arranged on the outside. These have a higher strength than the steel otherwise used here and can therefore have a smaller outer diameter than the ribs 30 . In this case, the ribs 30 act as mechanical protection for the reinforcement layers 37.

For reasons of legibility, the expression “at least one” has been partially omitted for the sake of simplicity. If a feature of the technology disclosed here is described in the singular or indefinitely (e.g. the/one pressure vessel, the/one rib, etc.), the plural should also be disclosed at the same time (e.g. the at least one pressure vessel, the at least one rib , Etc.).

The foregoing description of the present invention is for illustrative purposes only and not for the purpose of limiting the invention. Various changes and modifications can be made within the scope of the invention without departing from the scope of the invention and its equivalents.

Reference List

5

pressure vessel system

6

fasteners

7

connecting cable

8th

Valve

10

pressure vessel

15

inner space

20

container wall

25

first connection

26

second connection

30

outside rib

32

through holes

35

spaces

37

reinforcement layers

40

inside ribs

Claims (35)

Pressure vessel (10) for storing gaseous fuel, - Comprising a container wall (20) which encloses an interior (15), wherein on the container wall (20) one or more ribs (30, 40) are formed. Pressure vessel (10) after claim 1 wherein one, some or all of the ribs (30, 40) are formed of the same material as the container wall (20); and/or wherein one, some or all of the ribs (30, 40) are formed from a different material than the container wall (20); wherein one, some or all of the ribs (30, 40) are made of metal and/or carbon fiber reinforced plastic. A pressure vessel (10) as claimed in any preceding claim wherein bounding planes of some or all of the ribs (30,40) are oriented parallel to one another. Pressure vessel (10) according to any one of the preceding claims, wherein the ribs (30, 40) are of the same width and/or have the same spacing from each immediately adjacent ribs (30, 40). Pressure vessel (10) according to one of the preceding claims, wherein a wall thickness of the pressure vessel (10) between the ribs (30, 40) is at least 5.4 mm and/or at most 7.5 mm. Pressure vessel (10) according to one of the preceding claims, wherein a height of the ribs (30, 40) relative to the immediately surrounding vessel wall (20) is at least 1 mm, at least 2 mm, at least 4 mm or at least 6 mm; and/or wherein a height of the ribs (30, 40) relative to the immediately surrounding container wall (20) is at most 2 mm, at most 3 mm, at most 4 mm, at most 6 mm or at most 7 mm. Pressure vessel (10) according to one of the preceding claims, wherein a width of the ribs (30, 40) is at least 20 mm, at least 25 mm, at least 30 mm or at least 35 mm; and/or wherein a width of the ribs (30, 40) is at most 25 mm, at most 30 mm, at most 35 mm or at most 40 mm. Pressure vessel (10) according to one of the preceding claims, wherein a spacing of immediately adjacent ribs (30, 40) is at least 10 mm or at least 15 mm; and/or wherein a distance between immediately adjacent ribs (30, 40) is at most 15 mm or at most 20 mm. Pressure vessel (10) according to one of the preceding claims, wherein one or more circumferential reinforcement layers (37) are formed between immediately adjacent outer ribs (30). Pressure vessel (10) according to any one of the preceding claims, wherein the reinforcing layers (37) are formed from carbon fiber reinforced plastic. Pressure vessel (10) according to any one of the preceding claims, wherein the reinforcing layers (37) are unidirectional. Pressure vessel (10) according to one of the preceding claims, wherein a height of the ribs (30) is at least 20% and/or at most 30% greater than a height of the reinforcement layers (37). Pressure vessel (10) according to one of the preceding claims, wherein a barrier layer is formed between the vessel wall (20) and the interior (15). Pressure vessel (10) after Claim 13 , wherein the barrier layer completely lines the inside of the container wall (20). Pressure vessel (10) after Claim 13 or 14 wherein the barrier layer is formed of ethylene vinyl alcohol copolymer. Pressure vessel (10) after claim 15 , wherein the barrier layer has an ethylene content between 20 mol% and 28 mol%, or 24 mol%. Pressure vessel (10) according to any one of Claims 13 until 16 , wherein the barrier layer has a thickness between 80 µm and 250 µm. Pressure vessel (10) according to any one of Claims 13 until 17 , wherein a metal layer is arranged between the barrier layer and the container wall (20). Pressure vessel (10) after Claim 18 , wherein the metal layer is formed of copper or a copper alloy. Pressure vessel (10) according to any one of Claims 13 until 19 , wherein all the ribs (40) on the container wall (20) are formed on the outside. Pressure vessel (10) according to one of the preceding claims, wherein an anti-corrosion layer is applied to the outside of the vessel wall (20). Pressure vessel (10) after Claim 21 , wherein the anti-corrosion layer is formed from a zinc-nickel alloy. A pressure vessel (10) according to any one of the preceding claims, wherein one, some or all of the ribs (40) are formed on the inside of the vessel wall (20). A pressure vessel (10) as claimed in any preceding claim, wherein one, some or all of the ribs (30) are formed externally on the vessel wall (20). Pressure vessel system (5), comprising - Two or more pressure vessels (10) according to any one of the preceding claims, wherein ribs (30) of one, some or all pressure vessels (10) engage in spaces (35) between ribs (30) of one or more immediately adjacent pressure vessels (10). Pressure vessel system (5) after Claim 25 , wherein the longitudinal axes of the pressure vessels (10) are aligned parallel to one another. Pressure vessel system (5) after Claim 25 or 26 - wherein the ribs (30) of immediately adjacent pressure vessels (10) are designed without axial offset relative to at least one longitudinal end of the pressure vessel (10), and - wherein immediately adjacent pressure vessels (10) are arranged axially offset to one another. Pressure vessel system (5) according to one of Claims 25 until 27 - wherein the ribs (30) of immediately adjacent pressure vessels (10) are designed to be axially offset to the immediately adjacent pressure vessel (10), and - wherein immediately adjacent pressure vessels (10) are arranged axially non-offset with respect to one longitudinal end or both longitudinal ends. Pressure vessel system (5) according to one of Claims 25 until 28 wherein in ribs (30) directly adjacent pressure vessels (10) aligned through bores (32) are formed, through which a fastening means (6) runs. Pressure vessel system (5) according to one of Claims 25 until 29 , the ribs (30) of immediately adjacent pressure vessels (10) being non-positively connected to one another. Pressure vessel system (5) according to one of Claims 25 until 30 , wherein the pressure tanks (10) are connected by a common connecting line (7), with pressure equalization between the pressure tanks (10) not being impaired at any time by valves. Motor vehicle with a pressure vessel system (5) according to one of Claims 25 until 31 , wherein the pressure vessel system (5) is installed in an underfloor space of the motor vehicle. Method for forming ribs (30, 40) on a vessel wall (20) of a pressure vessel, comprising at least one of the following procedures: - separate production of the ribs (30, 40) and non-positive application of the ribs (30, 40) to the container wall (20) by means of cold forming, - subjecting the pressure vessel (10) to an internal pressure, thereby cold forming the pressure vessel (10) to form the ribs (30, 40), and/or - Separate production of the ribs (30, 40) and thermal shrinking of the ribs (30, 40) onto the container wall (20). procedure after Claim 33 , which further comprises a step of introducing a barrier layer on the inside of the container wall (20). procedure after Claim 34 , wherein the incorporation takes place by rotomoulding, blow molding or extrusion.

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