The invention relates to the production of a compressed gas tank and the compressed gas tank itself, in particular a compressed hydrogen tank.
From the prior art, compressed hydrogen tanks are known which are currently being produced by a plastic liner being wrapped by carbon fibres, which are already pre-impregnated or are impregnated after the winding. Here, the liner is necessary for giving the tank its basic shape. After the winding, the impregnated carbon fibre bandage is fixed in a known manner by curing the matrix polymer. Here, the line remains on the inner wall of the compressed hydrogen tank. During the operation of the tank, it can now arise that hydrogen diffuses through the wall of the liner and accumulates on the carbon fibre composite bandage. If, during the subsequent driving operation, the tank pressure drops, it can arise that the liner peels off from the carbon fibre bandage and, in the worst case scenario, collapses. In the prior art, this problem should be bypassed by multilayer liners that have a higher level of diffusion resistance in order to avoid the peeling off.
Such a compressed hydrogen tank is known from DE 10 2009 014 057 A1. It possesses a wall made from a fibre composite material and a liner made from plastic, as well as a fitting flange. DE 10 2009 014 057 A1 relates to the problem of preventing diffusion of the hydrogen gas or another gaseous medium from the interior of the pressure tank through the wall made from fibre composite material, which can occur by means of an additional liner as a gas or vapour barrier.
An inflatable, fibre-reinforced elastomeric bubble is known from DE 2124789 A, which is proposed as a shrinkable, and thus removable, core for the tank construction. A method for the production of a fibre-reinforced polymer bubble is known from DE 19803909 A1.
Based on this prior art, the object arises to create a compressed gas tank, in particular for hydrogen, which has no collapsible inner structure.
The method according to the invention for the production of compressed gas tanks made from carbon-fibre materials, having a filling and removal neck, such as a compressed hydrogen tank, for example, comprises, in a first embodiment, the following steps:
The impregnation of the carbon fibres can be carried out by using pre-impregnated carbon fibres for the wrapping; on the other hand, the complete carbon fibre bandage can also first be impregnated. Both variants can also be combined.
Further steps of the method are
It is thus possible for the compressed gas tank to be produced without a liner, whereby it arises that the problem of withdrawal is omitted.
According to the invention, the method has the following steps for reducing the material requirements and still causing no losses in stability of the compressed gas tank:
If the meltable core is provided, a support structure made from struts or spokes made from carbon fibre material is already provided in this. This can, in a suitable manner, consist of a spoke support structure that extends radially away from the central axis of the core. The free ends of the struts or spokes are thus to be of such a length that they protrude over the surface of the core that is to be wrapped. Then, during the wrapping of the core with the carbon fibre bandage, the protruding free ends of the struts or spokes can be wound into these. Thus, an advantageously firm connection is achieved. During the consolidation of the polymer matrix material, the free ends of the support structure, which are wound into the carbon fibre bandage, are then fixed. If the liquefaction and removal of the liquid core material from the compressed gas tank is now carried out, the support structure remains in the interior thereof in a stabilizing manner.
Wax or even water ice, for example, are considered as the meltable materials for the core. Here, water ice appears to be particularly suitable, since, if the winding is applied, it can be further cooled down in a temperature reduction step in order to provide the carbon fibre composite material bandage with pre-stressing during the winding process in order to achieve a high level of pressure resistance of the compressed gas tank. Thus, compressed gas tank material and weight can be saved.
The meltable core can have a round or, in particular, if it contains the support structure, an oval or another suitable cross-sectional shape, and it is thus possible to produce other cylindrical compressed gas tanks accordingly.
A compressed gas tank according to the invention, which can be produced with the above methods, and which has a filling and removal neck, therefore has a wall which consists of a carbon fibre composite material layer and which is, advantageously, free from a liner layer on the inner wall. This compressed gas tank can be a compressed hydrogen tank.
According to the invention, a support structure made from struts or spokes made from carbon fibre material is present in the interior of the compressed gas tank, which is stabilised and is advantageous with respect to material usage. This can preferably be configured as a spoke support structure, which extends radially away from a central axis of the compressed gas tank, the distal struts or spoke ends of which penetrate the inner wall of the compressed gas tank and are received in the polymer matrix of the carbon fibre composite material layer that forms the wall of the compressed gas tank.
Apart from a cylindrical shape, the compressed gas tank can therefore have an oval or another suitable cross-sectional shape in the case of a support structure being used.
These and other advantages are demonstrated by the description below with reference to the accompanying figures. The reference to the figures in the description serves to support the description and to facilitate understanding of the subject matter; they are merely one schematic depiction of one embodiment of the invention.
Here are shown:
At the end of the production process, the core that already contained the support structure made from spokes 3 was liquefied by melting, and the liquid core material was removed via the filling and removal neck.
If such spokes 3, which protrude radially from a central axis, are used, or if another support structure is potentially used, there even exists the possibility to depart from the cylindrical basic shape of a compressed hydrogen tank and, for example, to create an elliptical cross-section of the compressed hydrogen tank, as is shown in
Number | Date | Country | Kind |
---|---|---|---|
10 2011 116 656 | Oct 2011 | DE | national |
Filing Document | Filing Date | Country | Kind |
---|---|---|---|
PCT/EP2012/003932 | 9/20/2012 | WO | 00 |
Publishing Document | Publishing Date | Country | Kind |
---|---|---|---|
WO2013/056773 | 4/25/2013 | WO | A |
Number | Name | Date | Kind |
---|---|---|---|
1895747 | Beldimano | Jan 1933 | A |
2947439 | McGrath | Aug 1960 | A |
2982441 | Farrell | May 1961 | A |
3692551 | Weaver | Sep 1972 | A |
3712139 | Harvey | Jan 1973 | A |
3962393 | Blad | Jun 1976 | A |
5462193 | Schoo | Oct 1995 | A |
5647503 | Steele | Jul 1997 | A |
5704514 | Schoo | Jan 1998 | A |
6015065 | McAlister | Jan 2000 | A |
6090465 | Steele et al. | Jul 2000 | A |
6264868 | Marchant | Jul 2001 | B1 |
6325958 | Lombardi | Dec 2001 | B1 |
RE39554 | Steele | Apr 2007 | E |
7351364 | Morrison | Apr 2008 | B2 |
7670532 | Weaver | Mar 2010 | B1 |
20020033221 | Nakamura | Mar 2002 | A1 |
20140326738 | Knoop | Nov 2014 | A1 |
20150048554 | Karrer | Feb 2015 | A1 |
Number | Date | Country |
---|---|---|
1704604 | May 1971 | DE |
2124789 1 | Dec 1972 | DE |
19803909 | Aug 1999 | DE |
102005031039 | Jan 2007 | DE |
102009014057 | Sep 2010 | DE |
102009024794 | Dec 2010 | DE |
102009057170 | Sep 2011 | DE |
Entry |
---|
International Search Report in International Application No. PCT/EP2012/003932, dated Dec. 7, 2012. |
Number | Date | Country | |
---|---|---|---|
20140326738 A1 | Nov 2014 | US |