Hydrogen Storage System
A Hydrogen storage system comprising storage elements coupled to each other to form one or more containers disposed in a space having a volume V where the volume of each of the storage elements is much smaller than the volume V resulting in the storage elements experiencing reduced stress at their inner surfaces. Thus, Hydrogen can be stored at relatively high pressure within these storage elements due to the reduced stress experienced by their inner surfaces. Consequently, materials having relatively lower tensile strength and stiffness can be used to construct the storage elements of the Hydrogen storage system. Further, the storage elements can be shaped and sized to conform to a volume of space having an arbitrary shape and dimensions.
1. Field of the Invention
The present invention generally relates to hydrogen storage systems for a defined space and more particularly relates to the architecture, size, shape and positioning of such systems for a defined space in vehicles or in storage areas.
2. Description of the Related Art
Hydrogen is increasingly becoming a fuel used in all types of vehicles including bi-fuel vehicles where the other fuel is gasoline. There is however a key practical consideration associated with the use of Hydrogen as a fuel for vehicles. The key consideration is the storage of the hydrogen fuel itself; this consideration raises several issues. In particular, the size, cost of manufacture, and weight of hydrogen tanks are issues that complicate the design and practicability of such tanks Also, the storage mass of the Hydrogen is itself a key consideration.
A first issue is the size of the tanks relative to the space allocated to them in vehicles. Current hydrogen fuel tanks store hydrogen at a typical pressure of 200-350 bars where a “bar” is a unit of pressure defined in terms of kilopascals; that is 1 bar is equal to 100 kilopascals or 100 kPa; 1 kPa≡1000 Pa; 1 MPa≡1,000,000 Pa. The “pascal” is a well-known defined unit for the measurement of pressure, internal pressure, stress, Young's modulus (measure of stiffness of an isotropic elastic material), and tensile strength. At a pressure in the range of 200-350 bars, the amount of Hydrogen needed to be stored in a Hydrogen tank to be comparable to the energy content of a conventional gasoline tank often makes the size of the Hydrogen tank impractically large and in many cases impossible to install in the space allocated for the tank or in available space in the vehicle. Often the only available space is the trunk of an automobile and in many cases the size of a 200-350 bar tank would, for many vehicles, use virtually the entire trunk space reducing the overall usefulness of the vehicle. Typically, current hydrogen tanks have dimensions that are nearly the same as the dimensions of the space allocated to them. For example, many tanks occupy most if not the entire space of a trunk of a vehicle, which is the space that is usually allocated to such tanks
Current Hydrogen tanks are often cylindrical in shape and thus their design considerations are based on well known laws of physics regarding the internal pressure experienced by their inner surfaces when such cylinders contain gas, liquid or other matter. The effect of the internal pressure experienced by the internal surface of a cylindrical tank is expressed in terms of the stresses in the longitudinal axis of the cylinder and the stresses in the tangential directions (perpendicular to the longitudinal axis). The following equations, known as Kessel's equations, express the two types of stresses (axial stress or σa and tangential stress or σt) in terms of p (measurable pressure), D (diameter of cylinder) and s (thickness of the tank walls):
As can be clearly seen from the above equations, the stresses experienced by the internal surface of the cylinder in the axial and tangential directions are directly proportional to the inner diameter of the cylinder. Thus, for relatively large cylinders such as the 200-350 bar cylinders, there is increased stress due to the relatively large diameters, D. Because of the resulting higher stresses that occur, relatively strong fibers are needed to construct these tanks The cylindrical tanks are typically constructed using a relatively thin walled metallic cylinder reinforced with relatively strong fibers wound on the surface of the cylinder to which some type of polymer has been applied. Thus, the wound fibers are embedded in the polymer applied to the surface of the cylinder to form a FRP (Fiber Reinforced Polymer), which when cured serves as a strong shell adhered to the outer surface of the metallic cylinder so as to assist the inner metallic surface of the cylinder to withstand the resulting stresses as defined by equations (1) and (2) above.
The fibers used to construct the tanks are usually relatively strong fibers (such as carbon fibers), which have the requisite amount of tensile strength and stiffness to withstand the stresses resulting from relatively large diameter dimensions of the tanks The issue with these relatively strong fibers is their cost. Such fibers although used in many industrial and commercial products are not made in the quantity necessary to provide the benefits of the economies of scale typically provided by parts manufactured en masse in relatively high quantities. Carbon fibers and other fibers with comparable physical characteristics are relatively very expensive and thus the costs of manufacture of conventional hydrogen tanks are accordingly expensive.
Further, as previously stated, the 200-350 bar tanks do not have an energy capacity comparable to gasoline tanks Therefore, in order to increase the energy content of these tanks, the amount of hydrogen per unit volume is increased thus increasing the mass of hydrogen per unit volume and thus the energy content of the tank; this is done by increasing the internal pressure at which the Hydrogen is stored within the tank. For example, tanks having an internal pressure of 700 bars can be used. Such tanks will necessarily have more stress applied to their inner walls because of the increased pressure (See equations 1 and 2 above). With increasing pressure comes the need for strong fibers, which as described above makes the costs of such tanks relatively expensive.
A review of equations 1 and 2 above shows that one approach at reducing the stress on the inner walls of the 700 bar tanks, is to design tanks with thicker inner walls—that is, increasing s reduces σ. However, a tank with thicker inner walls will weigh more than the same tank with thinner inner walls. For storage tanks used in vehicles, the weight of the tank is clearly an important factor in the overall fuel efficiency of the vehicle. Also, in many cases the cost of manufacturing such thicker wall tanks increases due to the extra cost of additional wall material and modification in the manufacturing process for these tanks.
BRIEF SUMMARY OF THE INVENTIONThe present invention provides a Hydrogen storage system comprising N storage elements coupled to each other to form one or more containers that occupy or fit within boundaries of a defined space with boundaries, dimensions, and shape resulting in a volume V where N is an integer equal to 2 or greater. Each of the storage elements has a volume that is a fraction of (or substantially less than) the volume V resulting in each storage element and the one or more containers having reduced dimensions compared to the dimensions of the defined space of volume V. A fraction of the volume V refers to a volume of space occupied by one of N storage elements such that all N storage elements fit within the boundaries of the defined space of volume V. Because each of the storage elements has a volume that is substantially less than the overall volume V, the inner surfaces of each of the storage elements experience substantially less stress compared to the stress experienced by inner surfaces of one storage tank of volume V. That is, the volume of each of the storage elements is reduced to a value that allows usage of less costly but adequately strong fibers in the construction of such storage elements. As a result, the reduced stress experienced by the inner surfaces of each of the storage elements allows the usage of fiber material (e.g., Innegra, Basalt or other fiber having similar such properties) having relatively lower tensile strength and stiffness in the construction of each such storage element thus reducing the cost of the storage system.
The respective volumes of each of the storage elements are not necessarily equal to each other. For a system having N storage elements, each storage element has a volume defined by dimensions and shape that may be the same or different from the other storage elements. When all of the storage elements are coupled to each other to form one or more containers, the one or more containers have architectures defined by their shape and size and dimensions. All of the storage elements when coupled together fit in the defined space of Volume V either by conforming substantially to the shape and dimensions of the defined space or by being able to be disposed totally within the defined space of certain dimensions, boundaries and shape resulting in a volume V. The terms “conforming” or “conform” refer to the one or more containers forming a defined space that has substantially the same shape, dimensions, boundaries and volume, V of the defined space.
Each of the storage elements has an inner layer made of a Hydrogen impermeable material and an outer layer adhered to the outer surface of the inner layer. The outer layer may be a composite material made by first applying a resin (e.g., an epoxy resin) onto the outer surface of the inner layer and then winding a fiber onto the outer surface at a certain angle with respect to a defined point(s) of reference (e.g., longitudinal axis of a cylinder) thus embedding the fiber into the resin and allowing the fiber-resin combination to cure to form a relatively hard shell. Alternatively, the fiber can be wound first onto the outer surface of the inner layer and then a resin is applied; the fiber-resin combination is then allowed to cure to form a relatively hard shell. Yet further, the fiber material can be first weaved as a “sock” that is then snugly fit over the outer surface of the Hydrogen impermeable material. Resin is then applied to the fitted material and allowed to cure to form a relatively hard shell for the storage element. The process of slipping on the “sock” and then adding resin to the sock can be repeated as many times as desired. The “sock” refers to fibers weaved into the shape of a storage element so that a snug fit (i.e., a ‘glove’ fit) can be achieved when the “sock” is slipped on or over the outer surface of the storage element made from a Hydrogen impermeable material. Preferably, the Hydrogen impermeable material is aluminum or an aluminum alloy and the fiber is made from Basalt, Innegra, or other material with properties similar to Basalt or Innegra. Other Hydrogen impermeable materials and fiber materials that meet design requirements of the storage system of the present invention may be used. It will be readily obvious that the storage system of this embodiment and other embodiments of the present invention are not limited to the Hydrogen impermeable material and the fiber materials mentioned above.
In a first embodiment of the storage system of the present invention, all of the storage elements may be coupled to each other to form one or more containers positioned proximate each other within the boundaries of the defined space of volume V where the containers may be different in size, shape and architecture or they may all be the same in size, shape and architecture.
In a second embodiment of the storage system of the present invention, the storage elements may be coupled to each other to form one or more containers each of which is positioned within the boundaries of the defined space of volume V. Additionally, one or more other containers—not formed from storage elements—can also be positioned within the boundaries of the defined space of volume V. The containers formed from storage elements and containers not formed from the storage elements all fit within the boundaries of the defined space of volume V.
A particular implementation which can be used for the first and/or second embodiments of the present invention comprises storage elements having two types of shapes, viz., straight cylinders and bent cylinders having equal outer diameters (D0, where 2*r0=D0; r0 is the outer radius) and inner diameters (Di, where 2*ri=Di; ri is the inner radius); all of the bent cylinders have equal curve radii (rc). The curve radius for each of the bent cylinders is equal to k·D0 (i.e., rc=k·D0) where k is a real number greater than zero. Each of the bent and straight cylinders has a volume that is relatively much less than the volume V of a defined space within which these storage elements are disposed. The straight and bent cylinders are coupled to each other to form one or more serpentine cylindrical containers. Also, with the diameter having some measurable thickness so that there is an inner diameter Di and an outer diameter D0, the diameter value used in the Kessel equations is
DM is thus the mid-diameter or average diameter.
For the embodiments discussed above and any other embodiments falling within the claimed storage system of the present invention, the dimensions and shapes of the storage elements and/or containers (made and/or not made from storage elements) can be varied to construct a storage system in accordance with arbitrary design requirements. One particular set of design requirements puts limits on the size, cost and weight of the storage system. Also, depending on the shape of the defined space, the design requirements may also dictate the shape of the storage elements and the shape of containers made or not made from the storage elements.
The drawings shown in this application represent various embodiments of the Hydrogen storage system of the present invention. The various embodiments are not necessarily drawn to scale and are shown for illustrative purposes to further facilitate the description and explanation of Hydrogen storage system of the present invention. A brief description of the drawings is as follows:
The present invention provides a Hydrogen storage system comprising N storage elements coupled to each other to form one or more containers that occupy or fit within boundaries of a defined space with boundaries, dimensions, and shape resulting in a volume V where N is an integer equal to 2 or greater. Each of the storage elements has a volume that is a fraction of (or substantially less than) the volume V resulting in each storage element and the one or more containers having reduced dimensions compared to the dimensions of the defined space of volume V. A fraction of the volume V refers to a volume of space occupied by one of N storage elements such that all N storage elements fit within the boundaries of the defined space of volume V. Because each of the storage elements has a volume that is substantially less than the overall volume V, the inner surfaces of each of the storage elements experience substantially less stress compared to the stress experienced by inner surfaces of one storage tank of volume V. That is, the volume of each of the storage elements is reduced to a value that allows usage of less costly but adequately strong fibers in the construction of such storage elements. As a result, the reduced stress experienced by the inner surfaces of each of the storage elements allows the usage of fiber material (e.g., Innegra, Basalt or other fiber having similar such properties) having relatively lower tensile strength and stiffness in the construction of each such storage element thus reducing the cost of the storage system.
The respective volumes of each of the storage elements are not necessarily equal to each other. For a system having N storage elements, each storage element has a volume defined by dimensions and shape that may be the same or different from the other storage elements. When all of the storage elements are coupled to each other to form one or more containers, the one or more containers have architectures defined by their shape and size and dimensions. All of the storage elements when coupled together fit in the defined space of Volume V either by conforming to substantially the shape and dimensions of the defined space or by being able to be disposed totally within the defined space of certain dimensions, boundaries and shape resulting in a volume V. The terms “conforming” or “conform” refer to the one or more containers forming a defined space that has substantially the same shape, dimensions, boundaries and volume, V of the defined space.
Each of the storage elements has an inner layer made of a Hydrogen impermeable material and an outer layer adhered to the outer surface of the inner layer. The outer layer may be a composite material made by first applying a resin (e.g., an epoxy resin) onto the outer surface of the inner layer and then winding a fiber onto the outer surface at a certain angle with respect to a defined point(s) of reference (e.g., longitudinal axis of a cylinder) thus embedding the fiber into the resin and allowing the fiber-resin combination to cure to form a relatively hard shell. Alternatively, the fiber can be wound first onto the outer surface of the inner layer and then a resin is applied; the fiber-resin combination is then allowed to cure to form a relatively hard shell. Yet further, the fiber material can be first weaved as a “sock” that is then snugly fit over the outer surface of the Hydrogen impermeable material. Resin is then applied to the fitted material and allowed to cure to form a relatively hard shell for the storage element. The process of slipping on the “sock” and then adding resin to the sock can be repeated as many times as desired. The “sock” refers to fibers weaved into the shape of a storage element so that a snug fit (i.e., a ‘glove’ fit) can be achieved when the “sock” is slipped on or over the outer surface of the storage element made from a Hydrogen impermeable material. Preferably, the Hydrogen impermeable material is aluminum or an aluminum alloy and the fiber is made from Basalt, Innegra, or other material with properties similar to Basalt or Innegra. Other Hydrogen impermeable materials and fiber materials that meet design requirements of the storage system of the present invention may be used. It will be readily obvious that the storage system of this embodiment and other embodiments of the present invention are not limited to the Hydrogen impermeable material and the fiber materials mentioned above.
In a first embodiment of the storage system of the present invention, all of the storage elements may be coupled to each other to form one or more containers positioned proximate each other within the boundaries of the defined space of volume V where the containers may be different in size, shape and architecture or they may all be the same in size, shape and architecture.
In a second embodiment of the storage system of the present invention, the storage elements may be coupled to each other to form one or more containers each of which is positioned within the boundaries of the defined space of volume V. Additionally, one or more other containers—not formed from storage elements—can also be positioned within the boundaries of the defined space of volume V. The containers formed from storage elements and containers not formed from the storage elements all fit within the boundaries of the defined space of volume V.
A particular implementation which can be used for the first and/or second embodiments of the present invention comprises storage elements having two types of shapes, viz., straight cylinders and bent cylinders having equal outer diameters (D0, where 2*r0=D0; r0 is the outer radius) and inner diameters (Di, where 2*ri=Di; ri is the inner radius); all of the bent cylinders have equal curve radii (rc). The curve radius for each of the bent cylinders is equal to k·D0 (i.e., rc=k·D0) where k is a real number greater than zero. Each of the bent and straight cylinders has a volume that is relatively much less than the volume V of a defined space within which these storage elements are disposed. The straight and bent cylinders are coupled to each other to form one or more serpentine cylindrical containers. Also, with the diameter having some measurable thickness so that there is an inner diameter Di and an outer diameter D0, the diameter value used in the Kessel equations is
DM is thus the mid-diameter or average diameter.
For the embodiments discussed above and any other embodiments falling within the claimed storage system of the present invention, the dimensions and shapes of the storage elements and/or containers (made and/or not made from storage elements) can be varied to construct a storage system in accordance with arbitrary design requirements. One particular set of design requirements puts limits on the size, cost and weight of the storage system. Also, depending on the shape of the defined space, the design requirements may also dictate the shape of the storage elements and the shape of containers made or not made from the storage elements.
Referring to
Continuing with the description of
Referring to
The storage elements of short, long and bent cylinders depicted in
The volume V of the available trunk space of the 2009 Mitsubishi Evo 9 is 430 dm3. The formula for the volume of a cylinder (bent or straight) of length L, diameter DM (where DM=2rM;
and thickness s has a volume Vcyl=πrM2L or
The inner surface of a cylinder experiences stress from the pressure, p, of the stored Hydrogen in accordance with the axial and tangential stress equations (1) and (2) above which are hereby reproduced below for ease of reference:
Using the dimensions of the cylinders and the formula for the volume of a cylinder, the volume for each of the long cylinders is 0.75 dm3. The volume for each of the short cylinders is 0.34 dm3 and for each of the bent cylinders is 0.75 dm3. It is clear that the volume of the storage elements (i.e., long cylinders, short cylinders, and bent cylinders) are much smaller than the volume V of the defined space, viz., the volume of the trunk of the 2009 Mitsubishi Evo 9.
Each of the cylinder storage elements has a hardened shell adhered to its outer surface. The shell is made of a composite material, which includes fibers preferably made from Basalt (C2 fiber) or Innegra. One implementation of a cylinder storage element with a hardened shell is depicted in
To form the hardened outer shell or outer layer for the bent and/or straight cylinder sections, an epoxy resin is first applied to the outer surfaces of the extruded aluminum sections; the resin has a certain tensile strength, stiffness and density. A fiber is then wound (at a certain angle with respect to the longitudinal axis of the bent or straight cylinder) onto the outer surface at a certain angle (preferably 54.7°) with respect to the longitudinal axis 220 (or some other point of reference) of the cylinder. Alternatively, a fiber is first wound (at a certain angle—preferably 54.7°—with respect to the longitudinal axis of the bent or straight cylinders) and then the epoxy resin is applied to the outer surfaces of the extruded aluminum sections. The fibers are interwoven with each other creating a thickness of fibers.
Referring to
Another method that can be used to form the hardened outer shell is to use a fiber tubing process. In this process the fiber is first weaved onto a mandrel to follow the shape and dimensions of the mandrel forming a tube or “sock” or a weaved fiber having the shape of the storage element for which a hardened shell is being constructed. The mandrel has the same shape and dimensions as the storage element. The sock (or weaved fiber shape) is then frictionally and/or snugly fit over the outer surface of the storage element. Resin is then added to the fiber. The process can then be repeated with additional layers of fiber (with the proper adjustments made for the dimensions of the weaved fiber sock or weaved fiber shape) and resin as needed or desired. The layers of fibers and resin are then allowed to cure to form the hardened shell.
A fiber primarily made from volcanic rock such as Basalt rock is preferably used in the storage system of the present invention. For example, a Basalt fiber referred to as C2 fiber having a mineralogical composition comprises at least is 52% SiO2, 17% Al2O3, 9%CaO, 5% MgO and 17% of various other substances typically found in volcanic rock. Depending on the mechanical and chemical properties of the fibers that are desirable, various adjustments can be made to the composition. The fiber can also be an Innegra fiber. By using storage elements with reduced dimensions, the need for relatively very strong and expensive fibers is eliminated. Thus, fibers not as strong as the strongest fibers (e.g., carbon, steel or silicon carbide), which have acceptable mechanical and chemical properties (such as the properties of Basalt and Innegra) and are relatively inexpensive become excellent candidates for the construction of the storage elements and containers used in the storage system of the present invention. A comparative look at some representative fibers and their relative properties is shown in the table below:
The strongest fibers listed in the table above are those with the highest stiffness and tensile strength, viz., Dyneema, Silicon carbide, and Carbon. These fibers also have some of the highest specific strengths (or strength per density) in the table. The strength per density is the ratio of tensile strength to density, which is highest for Carbon and Dyneema. However when the strength of a fiber is related to its cost, the Basalt and Innegra fibers yield the highest value for the fibers in the table (specific strength per cost for Basalt is 159 and Innegra 176); this is because Basalt and Innegra are the least expensive fibers per unit weight (4 Euros per Kg for Innegra and 5 Euros per Kg for Basalt) of any of the fibers in the table. Therefore, Basalt, Innegra and other fibers with similar strength per cost values become excellent candidates for the storage system of the present invention because the sizes of the storage elements relative to conventional Hydrogen tanks allow the use of fibers that are not as strong as Carbon or Silicon carbide.
Various parameters related to the materials used to construct the storage elements and/or containers and the geometries of the containers and storage elements have a direct impact on the design of the storage system of the present invention. As discussed above, the three main considerations for the Hydrogen storage system of the present invention are its weight, size and cost. Some of the parameters that directly impact the weight, size and cost of the storage system of the present invention include choice of fiber material, thickness of the aluminum cylinders (or thickness of Hydrogen impermeable material), fiber fraction, (i.e., the ratio of amount of fiber to the amount of composite material made from fiber and epoxy resin) fiber angular positioning on the inner layer, the pressure at which the Hydrogen is stored and the dimension (in this case, the diameter of the cylinders) of the storage elements.
To design the storage elements and containers, one approach is to vary a dimension (say for example diameter, D) of a storage element. Through this approach, the varying parameter will determine the value of the parameters that are related to the size, weight and cost of the storage elements. For example, varying one key parameter such as increasing the diameter of the storage elements will decrease the weight of the storage element per Hydrogen unit and increase the mass of the Hydrogen that can be stored. This is because the increase in D increases the volume in a square relationship and increases the stresses in a linear relationship. For example, if D is doubled, the stresses increase by a factor of 2, but the volume increases by a factor of 22 or 4. Thus, the volume increases much more than the stresses for the same increase in D; keeping the amount of Hydrogen constant while increasing D results in a decrease of the weight per Hydrogen of the storage system. Clearly, however, the amount of Hydrogen that can be stored increases as D is increased. An increase in D will increase the stresses accordingly as already discussed and thus the fiber needed to withstand the resulting stress may be more expensive than what is called for by the design requirements.
Referring to
A modified version of the already discussed design approach for the storage system of the present invention is to define ranges for an acceptable minimal mass of Hydrogen and a maximum weight of the storage system. The diameter of the storage elements can then be calculated or determined to meet these design requirements. It is easily seen that the value of the diameter will determine the weight of the storage system, the size of the storage system. Further, the diameter value will determine the stress and thus the choice of fiber for the storage elements, which is a significant factor in the overall cost of the storage system.
Referring now to
The storage elements are not necessarily limited to cylinders or elements having circular profiles. Storage elements having rectangular, square, triangular, elliptical, arbitrarily configured profiles and other profiles can be considered as tubes (of various lengths) which can be coupled to each other to form containers that conform to the particular shape and contours of a defined space (with defined boundaries) having a volume V and which fit within the boundaries of the defined space. These tubes may be bent or shaped in various ways so that they fit within a particular defined space delineated by boundaries.
Referring now to
The embodiment shown in
The storage system shown in
The various embodiments described above all comprise storage elements that are cylindrical in shape and appropriately sized and dimensioned such that their relatively small volumes allow the use of relatively inexpensive materials having relatively lower tensile strength and stiffness to construct them. The following embodiment depicts a storage system in which the storage elements are not cylindrical but are arbitrary in shape and dimension and but they have relatively small volumes that allow the use of inexpensive materials in their construction. Thus, for the embodiments described above and the embodiment to be discussed below (
with i=2, 3, 4, 5, . . . , N and where each such volume V, is relatively small (compared to V; i.e., Vi<<V) such that the materials and techniques used in constructing the storage elements described with respect to
The particular embodiment shown in
Referring now to
Referring now to
Referring back to
The storage system of the present invention has been described in terms of storage elements that are coupled to each other to form containers within which Hydrogen is stored to power vehicles. It will be readily obvious however that the Hydrogen storage system of the present invention can be used for storage systems for various other applications such as storage systems for vehicles used to distribute Hydrogen to refill stations. These vehicles transport large amounts of Hydrogen in large tanks; the storage system of the present invention can be used to replace these large tanks The transported Hydrogen is delivered to refill stations for vehicles and is stored in storage tanks at those locations. Further the transported Hydrogen can be delivered to households or places of business, which use the delivered Hydrogen for heating systems and electricity generating systems. The storage system of the present invention can thus be used to transport Hydrogen to distribute the Hydrogen to refill stations. The present invention can be used to store Hydrogen at the refill stations. Further, the storage system of the present invention can be used to store Hydrogen in households or commercial buildings for heating or for generating electricity. Yet further, containers built in accordance with the storage system of the present invention and which are located at power stations can be used to generate electricity.
The storage system of the present invention has been described in terms of the various embodiments disclosed herein. It will be readily understood that the various embodiments discussed do not at all limit the scope of the present invention. One of ordinary skill to which the present invention belongs can, after reading this specification and the claims, implement the storage system of the present invention using other embodiments and implementations that are different from those disclosed herein but which are well within the scope of the claimed hydrogen storage system of the present invention.
Claims
1. A Hydrogen storage system to be disposed within a defined space of volume V, the hydrogen storage system comprising:
- N storage elements coupled to each other to form one or more containers that fit within the defined space where each storage element has a volume equal to a fraction of the volume V and N is an integer equal to 1 or greater.
2. The Hydrogen storage system of claim 1 where each of the storage elements has a volume and shape that are the same as other storage elements.
3. The Hydrogen storage system of claim 1 where some or all of the storage elements have different volumes and shapes.
4. The Hydrogen storage system of claim 1 where each of the storage elements has an inner layer made of hydrogen impermeable material and an outer layer made from a composite material.
5. The Hydrogen storage system of claim 1 further comprising one or more other containers not made from coupled storage elements and the one or more other containers are positioned proximate the one or more containers such that both types of containers fit within the defined space of volume V.
6. The Hydrogen storage system of claim 1 where the storage elements comprise long cylinders, short cylinders and bent cylinders all of which have an inner layer with equal inner and outer diameters and with corresponding inner and outer surfaces and where such inner layer is made from aluminum of a certain thickness.
7. The Hydrogen storage system of claim 6 where the bent cylinders are curved cylinders with a curve radius equal to k·D0 where k is an integer equal to a real number greater than zero and D0 is the outer diameter of the bent cylinder.
8. The Hydrogen storage system of claim 7 where k is equal to 2.
9. The Hydrogen storage system of claim 6 where the long cylinders, short cylinders and bent cylinders are coupled to form a serpentine cylindrical container having the inner layer and an outer layer made of a composite material adhered to the outer surface of the inner layer.
10. The Hydrogen storage system of claim 9 where the outer layer comprises resin applied to the outer surfaces of the inner layer and Basalt fibers wound onto the resin applied to the outer surfaces of the inner layer at a 45 degree angle with respect to a longitudinal axis of each of the coupled storage elements.
11. The Hydrogen storage system of claim 9 where the outer layer comprises resin applied to the outer surfaces of the inner layer and Innegra fibers wound onto the resin applied to the outer surfaces of the inner layer at a 45 degree angle with respect to a longitudinal axis of each of the coupled storage elements.
12. The Hydrogen storage system of claim 9 comprising a plurality of serpentine containers positioned proximate each other to fit within the defined space of volume V.
13. The Hydrogen storage system of claim 6 where the long cylinders, short cylinders and bent cylinders are coupled to form one or more serpentine cylindrical containers and one or more other containers not formed from the long cylinders, short cylinders and bent cylinders and all of the containers are positioned proximate each other to fit within the defined space of volume V.
14. The Hydrogen storage system of claim 13 where the one or more other containers are spherical containers.
15. The Hydrogen storage system of claim 6 where each of the storage elements has a circular cross section profile.
16. The Hydrogen storage system of claim 6 where the storage elements have different cross section profiles.
17. The Hydrogen storage system of claim 1 where the storage elements are coupled to each other via a common distribution conduit.
18. The Hydrogen storage system of claim 17 where the storage elements are U-shaped cylinders.
19. The Hydrogen storage system of claim 17 where the storage elements are capsules.
20. A Hydrogen storage system to be disposed within a defined space of volume V having an arbitrary shape and dimensions, the hydrogen storage system comprising: V N where N is an integer equal to 2 or greater and the storage elements are coupled to each other to form a container that conforms to the shape and dimensions of the defined space.
- N storage elements each having a volume equal to or less than
21. The Hydrogen storage system of claim 20 where the container comprises one or more sections coupled to each other and positioned in relatively close proximity to each other or are attached to each other.
22. The Hydrogen storage system of claim 21 where each of the sections comprises a plurality of the N storage elements coupled together.
23. The Hydrogen storage system of claim 20 where each of the storage elements is made from a Hydrogen impermeable material having an outer surface to which a composite material is adhered.
24. The Hydrogen storage system of claim 23 where the composite material comprises resin and fibers made from Basalt rock
25. The Hydrogen storage system of claim 23 where the composite material comprises resin and fibers made from Innegra.
26. A Hydrogen storage system to be disposed within a defined space of volume V having an arbitrary shape and dimensions, the hydrogen storage system comprising: V N where N is an integer equal to 2 or greater and the storage elements are coupled to each other to form one or more containers that fit within the defined space.
- N storage elements each having a volume equal to or less than
27. The Hydrogen storage system of claim 26 where the one or more containers are coupled to each other.
Type: Application
Filed: Oct 18, 2011
Publication Date: Apr 18, 2013
Inventor: Jörg Wellnitz (Walting/Gungolding)
Application Number: 13/275,493