Tessellated load-bearing insulation structure for thermal containers

Abstract

Examples relate to a tessellated load-bearing insulation structure for cryogenic fluid storage, particularly in insulated thermal containers. The tessellated insulation structure provides structural support, minimizing weight and enhancing durability under thermal cycling. The solution involves a multilayer insulation system comprising alternating layers of tessellated spacer layers and reflective films, enclosed within a vacuum shell that maintains hermetic sealing and supports external pressure on the vacuum shell of up to one atmosphere. The tessellated design minimizes thermal conductivity by reducing contact points between layers, while the structure's flexibility allows the insulation system to conform to complex tank geometries. Principal uses include aerospace applications where weight efficiency and thermal management are important. The tessellated insulation structure employs high-performance materials like polyetherimide and metallized polymer films, with self-evacuating cells enhancing insulation efficiency. The method of manufacture involves layering and sealing within the vacuum shell, ensuring structural integrity and thermal isolation.

Description

TESSELLATED LOAD-BEARING INSULATION STRUCTURE FOR THERMAL CONTAINERSCLAIM OF PRIORITY

[0001]

[0001] This patent application claims the benefit of priority to U.S. Provisional Application Serial No. 63 / 632,403, filed April 10, 2024, which is incorporated by reference herein in its entirety.TECHNICAL FIELD

[0002] This disclosure pertains to thermal container technology and, in some examples, to tessellated load-bearing insulation structures for cryogenic fluid storage.BACKGROUND

[0003] Thermal containers, designed to maintain certain temperature ranges, include storage systems such as cryogenic tanks for ultra-low-temperature fluids like liquid hydrogen or liquid nitrogen. Cryogenic applications involve careful considerations due to the extreme conditions necessary to maintain these fluids in a liquefied state. Thermal insulation systems function by attenuating heat transfer mechanisms including conduction, convection, and radiation to control boil-off while accounting for mechanical and operational factors including weight, durability, and structural integrity. Repeated thermal cycling and mechanical stresses introduce additional demands on longterm performance. These aspects represent ongoing considerations for cryogenic storage technology across different geometries and environmental conditions.BRIEF DESCRIPTION OF THE DRAWINGS

[0004] In the drawings, which are not necessarily drawn to scale, like numerals may describe similar components in different views. Like numerals having different letter suffixes may represent different instances of similar components. The drawings illustrate generally, by way of example, but not by way of limitation, various embodiments discussed in the present document.

[0005] FIG. 1 is a plan view illustrating an aerodynamic vehicle in the form of an aircraft, according to some examples.

[0006] FIG. 2 is a schematic view illustrating an energy supply system for an aerodynamic vehicle, according to some examples.

[0007] FIG. 3 is a cutaway side view illustrating a cryogenic tank insulated with a tessellated load-bearing multilayer insulation structure, according to some examples.

[0008] FIG. 4 is a cutaway side view illustrating the tessellated load-bearing multilayer insulation structure, according to some examples.

[0009] FIG. 5 is a cutaway plan view illustrating two layers of a hexagonal tessellated spacer layer with offset adjacent layers, according to some examples.

[0010] FIG. 6 is a cutaway plan view illustrating a curved tessellated spacer layer that is more flexible than a hexagonal tessellated spacer layer, according to some examples.

[0011] FIG. 7 is a flowchart illustrating a method of manufacturing a thermal insulation system for a cryogenic tank that stores cryogenic fluid, according to some examples.DETAILED DESCRIPTION

[0012] The following description of examples is not intended to limit the scope to these examples, but rather to enable any person skilled in the art to make and use the disclosed technology.Overview

[0013] The transportation industry is increasingly adopting hydrogen as a promising fuel for zero-emission propulsion. With an energy-density-per-unit mass three times higher than traditional jet fuel, hydrogen offers an attractive alternative for reducing emissions by producing no CO2 or NOx emissions compared to traditional combustion engines. Liquid hydrogen is typically preferred over compressed hydrogen gas due to its higher energy density and lower storage volume requirements.

[0014] In aerospace, automotive, and other high-performance applications, efficient storage of cryogenic liquids like liquid hydrogen is critical. Cryogenic insulation technology maintains the extremely low temperatures required for these fuels by protecting against heat transfer through mechanisms such as radiation, conduction, and convection. Ideally, cryogenic storage systems are designed to provide superior thermal management while ensuring minimal contribution to overall mass. As industries seek higher energy efficiencies and longer operational life cycles, cryogenic insulation systems is increasing designed to protect fuel integrity while reducing weight.

[0015] To achieve this balance, designers of vehicles powered by liquid hydrogen or other cryogenic liquids seek to increase the vehicle’s mass fraction. A higher mass fraction is particularly beneficial in applications where reducing weight is crucial, such as aerospace propulsion. Insulation technology used on the cryogenic containers storing the liquid fuel attempts to effectively combine thermal protection with mechanical support to ensure that the fuel tank remains safe and operational under varying conditions. These goals drive the development of insulation structures that offer durability and thermal performance at the lowest possible weight.

[0016] Existing cryogenic insulation systems for cryogenic fluid storage exhibit several technical limitations. Conventional approaches often utilize materials with excessive density, increasing overall system mass and reducing mass fraction — a critical parameter for vehicle performance. These systems frequently suffer from performance degradation when exposed to repeated thermal cycling, as material fatigue leads to structural compromise and diminished thermal resistance over time. Additionally, many current solutions separate structural support functions from thermal insulation properties, requiring supplementary load-bearing components that add mass and may introduce thermal bridging effects. Furthermore, many current insulation materials lack sufficient flexibility to conform to complex tank geometries, resulting in incomplete thermal protection and reduced system efficiency.

[0017] Notably, some existing thermal insulation solutions are designed to operate in a vacuum (such as on spacecraft) and thus do not need to, and often are not capable of, supporting a load of up to one atmosphere. In other words, these solutions are not “self- supporting.” As used herein, a self-supporting thermal insulation system is defined asone that inherently combines structural load-bearing capability, capable of supporting a load of up to one Earth atmosphere, along with thermal isolation properties without requiring external supporting elements.

[0018] Designing a support structure for insulation that enables an ultra-thin, loadbearing barrier without degrading thermal resistance requires addressing competing material and geometric constraints. The insulation structure should reliably support external loads and withstand daily stresses without compromising system integrity or causing heat leaks. Additionally, the insulation structure can conform to complex tank shapes and endure repeated thermal cycles without fatigue. Addressing these issues serves to advance cryogenic storage technology and improves the efficiency and safety of modern fuel systems.

[0019] The described technology overcomes these challenges through an optimized insulation architecture that achieves both thermal performance and structural integrity. The approach provides excellent thermal resistance while minimizing mass contribution, thereby preserving mass fraction. The design demonstrates enhanced durability under repeated thermal cycling without performance degradation. By incorporating loadbearing capability directly into the insulation structure, the technology eliminates the need for separate support components while mitigating thermal bridging. The system's adaptable configuration ensures complete coverage of complex tank geometries, maintaining consistent thermal protection across surfaces.

[0020] This integrated approach to cryogenic insulation resolves the inherent compromises between thermal resistance and mechanical strength that have limited current designs. The resulting system offers improvements in energy efficiency, operational reliability, and safety for liquid hydrogen storage. These advancements support broader implementation of hydrogen fuel systems across transportation applications, particularly in weight-sensitive domains such as aerospace propulsion where performance optimization is useful.

[0021] The described thermal insulation system for cryogenic tanks represents an advanced approach through its implementation of a tessellated insulation structure thatintegrates both thermal insulation and structural load-bearing functions. This integrated design enables the use of an ultra-thin vacuum shell while maintaining vacuum integrity, achieved through a precisely engineered tessellation pattern that minimizes thermal conductivity by strategically reducing physical contact points between adjacent layers. The system's architecture employs a multi-layer arrangement of rigid insulating structures and reflective films, forming a self-supporting matrix that eliminates the need for separate support components.

[0022] One technical feature involves the incorporation of self-evacuating cells within the tessellated structure, where contained gases undergo cryogenic pumping at operational temperatures to enhance insulation efficiency. The system utilizes high- performance materials, including polyetherimide and metallized polyimide films, optimized for both thermal and mechanical performance. An integrated indexing mechanism ensures proper layer alignment, maintaining the critical offset relationship between adjacent tessellated layers to preserve thermal isolation while enabling structural load transfer.

[0023] This technical approach provides several advantages over conventional insulation systems, including improved mass fraction through weight reduction, enhanced thermal performance, and increased reliability under operational conditions. The combination of self-supporting structural capability with advanced thermal insulation properties makes the system particularly suitable for aerospace applications where both weight efficiency and thermal management are paramount. The design's adaptability to complex tank geometries and its ability to maintain performance through thermal cycling further contribute to its operational effectiveness in cryogenic storage applications.Description

[0024] The tessellated insulation structure disclosed herein increases the mass fraction of the cryogenic tank storing liquid hydrogen tanks. The support and insulative properties of the tessellated insulation structure allow a thin vacuum shell to be used without compromising the vacuum. The tessellated insulation structure does double duty by both insulating the cryogenic tank and supporting the load of the thin vacuum shell against outside pressure of up to one atmosphere.

[0025] Tessellation is the tiling or covering of a surface using one or more geometric shapes. This tiling or covering has no overlaps and no gaps. The geometric shapes typically are a pattern of polygons that lend themselves to covering the surface with no overlaps or gaps. In some cases, the pattern is a single polygon that repeats itself. In other cases, the pattern is a mix of two or more polygons, and that pattern repeats itself. Tessellation also provides flexibility to the tessellated insulation structure that allows it to conform to curved surface, such as the shape of a cryogenic tank. Various tessellation patterns will have better, or worse, flexibility as compared to each other. These tessellation patterns include triangles, hexagons, squares, rectangles, polygons, and curved variations of these shapes.

[0026] The tessellated insulation structure insulates the cryogenic tank in at least three ways. First, the tessellated insulation structure uses a radiation barrier to insulate against radiation. Second, because in some examples there is a vacuum inside the tessellated insulation structure, it can insulate against any convective activities by eliminating any convective gases. And third, the tessellated insulation structure minimizes thermal conductivity between the vacuum shell and the cryogenic tank by an offset mechanism that minimizes the physical contact between the vacuum shell and the cryogenic tank as well as intervening layers. One overarching consideration for selecting a tessellation pattern for the tessellated insulation structure is to minimize thermal conductivity between the layers of the tessellated insulation structure. The tessellation pattern is selected based in part on minimizing points of physical contact between adjacent layers of the tessellated insulation structure.

[0027] FIG. 1 is a plan view of an aerodynamic vehicle in the form of an aircraft 100 according to some examples. The aircraft is powered by liquid hydrogen fuel that is stored in an insulated cryogenic tank 118 that is insulated with a tessellated insulation structure, which is described herein. In some examples, the aircraft includes a plurality of cryogenic tanks that are like the insulated cryogenic tank 118 shown in FIG. 1.

[0028] The aircraft 100 includes a fuselage 114, two wings 112, an empennage 110, and propulsion systems 108 embodied as ducted fans or rotor assemblies 116 located in nacelles 102. The aircraft 100 includes one or more fuel cell stacks embodied in FIG. 1as nacelle fuel cell stacks 104 and wing fuel cell stacks 106. One or more heat exchangers 120 are in the wings 112, the fuselage 114, nacelles 102, or other locations. Note that the fuel cell stacks 104, 106 and heat exchangers 120 in some examples are positioned in locations other than those shown in FIG. 1. For instance, in some examples, the fuel cell stacks, and heat exchangers are in one or more of the leading edges of wings or other aerosurfaces, wing nacelles, fuselage noses or in scoops sticking out from the sides of aircraft fuselages, wings, or nacelles.

[0029] The aircraft 100 will also typically include associated equipment such as an electronic infrastructure, control surfaces, a cooling system, landing gear and so forth. The wings 112 function to generate lift to support the aircraft 100 during forward flight. In some examples the wings 112 can additionally or alternately function to structurally support the fuel cell stacks 104, 106 and / or propulsion systems 108 under the influence of various structural stresses (e.g., aerodynamic forces, gravitational forces, propulsive forces, external point loads, distributed loads, and / or body forces, and so forth).

[0030] FIG. 2 is a schematic view of an energy supply system 200 for an aerodynamic vehicle (such as the aircraft 100 shown in FIG. 1) according to some examples. As shown, the energy supply system 200 includes one or more fuel cells 212. Each fuel cell 212 may include one or more fuel cell stacks 208. Associated with a fuel cell 212 are a source of hydrogen, such as liquid hydrogen stored in the insulated cryogenic tank 118, a recirculation system 202 for supplying and returning hydrogen to the fuel cell 212, a coolant fluid circulation system 204 for transferring heat, power electronics 206 for regulating delivery of electrical power from the fuel cells 212 during operation and to provide integration of the fuel cells 212 with the electronic infrastructure of the aircraft 100, and a compressor / cathode air system 210 for providing compressed air to the fuel cells 212. The electronic infrastructure can include an energy supply management system, for monitoring and controlling operation of the fuel cells 212.

[0031] The fuel cells 212 function to convert chemical energy into electrical energy for supply to the propulsion systems 108. Fuel cells 212 can be arranged and / or distributed about the aircraft 100 in any suitable manner. Fuel cell stacks can be arranged within wings (e.g., inside of an airfoil cavity), inside nacelles, and / or, as discussed below, in any other suitable location on the aircraft 100.

[0032] Also provided may be one or more battery packs for energy storage for start-up, for peak power loads, load following, and for control and avionics safety in case of a failure in the fuel cell system. In some examples this provides a hybrid fuel cell and battery pack system, in which the propulsion systems 108 are powered jointly or alternately by the fuel cells 212 and battery packs, and in which the fuel cells 212 recharge the battery packs as needed.

[0033] The energy supply system 200 can optionally include a heat transfer system (e.g., fluid circulation system 204) that functions to transfer heat from or to various components of the aircraft 100, for example by circulating a working fluid within a fuel cell 212 to remove heat generated during operation, to provide heat for evaporation of liquid hydrogen from the insulated cryogenic tank 118, or to remove heat from other heat-generating components within the aircraft 100.

[0034] FIG. 3 is a cutaway side view of the insulated cryogenic tank 118, shown in FIGS. 1 and 2, and insulated with the tessellated insulation structure, according to some examples of this disclosure. Referring to FIG. 3, the insulated cryogenic tank 118 includes an inner tank 310 (or dewar) that contains a cryogenic fluid 320. In some examples, the cryogenic fluid 320 is liquid hydrogen.

[0035] The insulated cryogenic tank 118 also includes the tessellated insulation structure 330. A part of the tessellated insulation structure 330 is a containment shell (in some examples, a vacuum shell 340) that hermetically seals that tessellated insulation structure 330. In some examples, the vacuum shell 340 is made of at least one of the following materials: (a) stainless steel; (b) aluminum; (c) titanium; and (d) a polymer- metal laminate. In addition, as explained in detail below, the underlying structure of the tessellated insulation structure 330 serves to both insulate the inner tank 310 and support the vacuum shell 340 bearing a load of up to one atmosphere.

[0036] Other components of the insulated cryogenic tank 118 shown in FIG. 3 include an access port 350. The access port 350 is an opening to the inner tank 310 that provides access to the interior of the inner tank 310 and associated equipment within the inner tank 310 to allow servicing, maintenance, or cleaning. In addition, the insulatedcryogenic tank 118 includes a diffuser 355 to help safely refuel and reduce any splash loss of the cryogenic fluid 320.

[0037] An inner stiffening ring 360 supports the weight of the inner tank 310 and the cryogenic fluid 320. An outer stiffening ring 365 serves to support the entire insulated cryogenic tank 118. A vent line 370 is a safety feature that is used to vent vapor from the inner tank 310 and relieve any overpressure to avoid damage to the inner tank 310. A fill and drain line 375 is used to both fill the inner tank 310 with the cryogenic fluid 320 and to drain off the cryogenic fluid 320 when necessary.

[0038] FIG. 4 is a cutaway side view of the tessellated insulation structure 330 shown in FIG. 3 according to some examples of this disclosure. The tessellated insulation structure 330 is an example of a multilayer insulation structure for insulating the cryogenic tank 118 that stores a cryogenic fluid, such as liquid hydrogen. In the example shown in FIG. 4, the tessellated insulation structure 330 uses one or more layers of a tessellated layer (which in some examples is a polymer hexagonal tessellated layer) alternating with a thin radiation barrier. In some examples, the radiation barrier is a reflective film. This reflective film, in some examples, may be made of a polymer film with a thin layer of reflective material deposited on the upper side of the polymer film, the bottom side of the polymer film, or both. In some examples, the reflective material is at least one of (a) aluminum; (b) gold; and (c) silver. In some examples the layer of reflective material on the polymer film is quite thin. Some examples have a reflective material layer on the order of 0.1 microns.

[0039] The resultant tessellated insulation structure 330 creates a lightweight vacuum insulation that both supports a thin vacuum shell 340 and provides insulation for the cryogenic tank 118. In some examples, such shown in FIG. 4, the overall thickness of the tessellated insulation structure 330 is less than approximately one inch.

[0040] The tessellated insulation structure 330 is “self-supporting,” meaning that it inherently combines structural load-bearing capability — capable of supporting a load of up to one Earth atmosphere — with thermal isolation properties without requiring external supporting elements. This integrated design fundamentally differs from current insulation systems by eliminating the need for supplemental components such as spacers,gap maintainers, compressible blankets, or separate load-bearing members. Its mechanical integrity is achieved through the intrinsic material properties and geometric configuration of the insulation itself, which may take the form of rigid interlocking panels, lattice frameworks, or precisely engineered tessellated matrices that directly distribute structural loads.

[0041] The thermal isolation function is maintained autonomously through the system's inherent design rather than through additional thermal barriers or external supports. By unifying structural and thermal functions into a single cohesive architecture, the insulating elements themselves serve the dual purpose of bearing mechanical loads (including atmospheric pressure) while simultaneously providing effective thermal resistance. This integrated approach is distinguished over current systems that rely on separate structural frameworks and thermal management components, as well as vacuum-based insulation solutions that cannot support such loads. The self-supporting nature of the tessellated insulation structure 330 enables more efficient designs, particularly in weight-sensitive applications such as aerospace cryogenic storage systems, where minimizing auxiliary support structures is essential for achieving useful mass fractions while maintaining superior thermal performance.

[0042] Referring to FIG. 4, the tessellated insulation structure 330 includes a first layer of a radiation barrier 410. This first layer of the radiation barrier 410 includes occasional holes to allow venting between the different layers of the tessellated insulation structure 330. In some examples, there is a hole in the first layer of a radiation barrier 410 in at least one cell. In some examples, this first layer of the radiation barrier 410 is a first reflective film, such as a polymer reflective layer. The first layer of the radiation barrier 410 is in contact with a surface of the cryogenic tank 118. As shown in FIG. 4, in some examples this surface of the cryogenic tank 118 is also an outer wall of the inner tank 310.

[0043] On top of the first layer of the radiation barrier 410 is a first layer of a tessellated layer 420. In some examples, the first layer of the tessellated layer 420 is a first polymer hexagonal tessellated layer. On top of the first layer of the tessellated layer 420 is a second layer of the radiation barrier 430. Similar to the first layer of the radiation barrier 410, the second layer of the radiation barrier 430 includes occasional holes to allow venting between the different layers of the tessellated insulation structure330. In some examples, there is a hole at every cell in the second layer of the radiation barrier 430. In some examples, this is a second reflective film, such as a second polymer reflective layer. On top of the second layer of the radiation barrier 430 is a second layer of the tessellated layer 440. In some examples, this is a second polymer hexagonal tessellated layer. Similarly, alternating layers of a plurality of radiation barriers and a plurality of tessellated layers are stacked in this manner until the desired number of layers is achieved. In other words, the plurality of radiation barriers and the plurality of tessellated layers are positioned in an alternating fashion on top of each other starting with a radiation barrier in contact with an outer surface of the cryogenic tank 118 and ending with the vacuum shell 340 on top of a tessellated layer that is outermost from an outer surface of the inner tank 310 and adjacent to the inner surface of the vacuum shell 340.

[0044] The vacuum shell 340 is overlayed on top of a final layer of the tessellated layer 450. The vacuum shell 340 provides a hermetic seal to the multilayer insulation structure, in other words the alternating layers of radiation barriers and tessellated layers. In addition, this multilayer insulation structure below the vacuum shell 340 helps the vacuum shell 340 support a load of up to one atmosphere on the vacuum shell 340 without significant deformation, collapse, or compression.

[0045] The tessellated insulation structure 330 is flexible such that its lightweight multilayer material conforms to the outer surface of the cryogenic tank 118. In some examples, the tessellated insulation structure 330 is wrapped around an outside of the cryogenic tank 118. This is achievable even at the curved ends of the cryogenic tank 118 because the tessellated insulation structure 330 is flexible and conforms to the shape of the cryogenic tank 118. In some examples, the layers of the radiation barrier (or polymer reflective layers) are made from mylar that has a thin coating aluminum on both sides, or double-aluminized mylar. In other examples, the material is a polyimide film with a thin layer of aluminum deposited on either side. In some examples the double aluminized polyimide film has a thickness of approximately 1 thousandth of an inch. In other examples, the material is a reflective material made from at least one of aluminum, silver, and gold.

[0046] In some examples, this material is laminate with a 5-mil polyimide film bonded to aluminum foil. This laminate is exceptionally light but not extremely robust. A metal layer on at least one side of the polyimide film is desirable to keep the permeation to an acceptable level. In other examples, the material is a reflective material made from at least one of aluminum, silver, and gold. Some examples may use a spray-on foam insulation with a laminate shell, where the spray-on foam insulation may be divided into sections.

[0047] In some examples, the vacuum shell 340 made from one or more of any combination of stainless steel, aluminum, and titanium. In other examples, it is made from stainless steel alone, which is typically easier to weld. In still other examples, it is made from a combination of stainless steel and fiberglass. Usually, the vacuum shell 340 contains some type of metal to minimize the permeation of air into the high vacuum inside of the tessellated insulation structure 330. In some examples, the vacuum shell 340 has a thickness of between five-thousandths of an inch and sixty -thousandths of an inch.

[0048] Each layer of tessellated layers contains a plurality of individual cells, and each of these individual cells is configured to support the vacuum shell 340. In some examples, the cross-sectional shape of a cell is a polygon. In other examples, this polygon is a hexagon. In general, the geometry of a hexagon minimizes the amount of material used to make the structure (as compared to other structural designs), thereby minimizing weight. Moreover, a hexagonal tessellated layer provides excellent support to the thin vacuum shell 340 because of its relatively high compression properties.

[0049] In some examples, the tessellated layer is made from a high-performance plastic. In other examples, the high-performance plastic uses sputter coating to coat the high-performance plastic with a thin aluminum coating to enhance radiation barrier properties. In some examples, the high-performance plastic is polyetherimide.

[0050] In some examples, at least some of the individual cells of the tessellated layer are filled with a gas that cryogenically pumps at a temperature of the cryogenic fluid. In other examples, the gas is carbon dioxide, and the cryogenic fluid is liquid hydrogen. In these examples, the carbon dioxide gas is turned into a solid at the temperature of theliquid hydrogen in order to evacuate each of individual hexagonal cells filled with carbon dioxide.

[0051] In some examples, the individual cells are designed such that each of the individual cells allows gas communication between them. In some examples, each individual cell has a hole or a groove in at least one of its walls to allow this gas communication so that gas can pass freely between cells at room temperature. In some examples, the hole or groove is at the top or at the bottom of the individual cell wall. In other examples, such as is shown in FIG. 4, small diameter holes 460 are made in at least one of the walls of the individual cell to provide for this gas communication.

[0052] In some examples, the tessellated insulation structure 330 contains at least one layer of polymer netting wrapping the first layer of the radiation barrier 410 and the first layer of the tessellated layer 420. The polymer netting is wrapped around the first layer of the tessellated layer 420 such that the polymer netting is in contact with the first layer of the tessellated layer 420. Similarly, addition polymer layers may be used to wrap the second layer of the tessellated layer 440 such that the additional polymer layers are in contact with the second layer of the tessellated layer 440. This process may continue with addition polymer layers until the final layer of the tessellated layer 450 is wrapped with a final polymer layer such that the final polymer layer is in contact with the final layer of the tessellated layer 450.

[0053] In the tessellated insulation structure 330, the polymer netting layers form individual cells within the self-supporting tessellated insulation assembly. These polymer netting layers are strategically integrated to facilitate gas communication between adjacent cells, which is essential for both evacuation and self-evacuation processes. The polymer netting creates a flexible and interconnected network of cells that allows gases to move freely between them. This design ensures that any gas trapped within the cells can be efficiently evacuated, maintaining the vacuum necessary for useful thermal insulation. Additionally, the configuration of the polymer netting supports the structural integrity of the tessellated insulation structure 330 by distributing mechanical loads evenly across the tessellated layers. This arrangement enhances the thermal performance of the system by minimizing thermal conduction and also ensuresthat the insulation assembly can withstand external pressures of up to one atmosphere without compromising its insulating properties.

[0054] The tessellated insulation structure 330 is designed to absorb shock in the event of a crash situation and protect the cryogenic tank 118 from rupturing. For example, in the event of a crash situation the vacuum shell 340 may be compromised, and the vacuum within the tessellated insulation structure 330 will be lost. But the tessellated layers in the tessellated insulation structure 330 will absorb some of the shock of the crash, thereby protecting the cryogenic tank 118 from rupture.

[0055] FIG. 5 is a plan view of two layers of a hexagonal tessellated layer of the tessellated insulation structure shown in FIG. 4 illustrating the offset of two adjacent hexagonal tessellated layers. As shown in FIG. 5, the cross-sectional shape of each of the plurality of individual cells is a hexagon. However, the cross-sectional shape of each individual cell can be any one of a variety of polygonal or other regular or irregular shapes. In some examples, the cross-sectional shape is any one of a triangle, square, rectangle, hexagon, polygon, or some curved variation of these shapes.

[0056] As shown in FIG. 5, the individual hexagonal cells are arranged in rows and columns. In other examples, they may be arranged as individual cells not necessarily having a pattern. In some examples, some of the individual hexagonal cells are discontinuous, meaning that a cell does not have an adjacent cell. Moreover, the cell may not be an entire cell but may be a portion of a cell. Discontiguous cells are shown in FIG. 5 at the perimeter of the hexagonal tessellated layers.

[0057] Referring to FIG. 5, a first hexagonal tessellated layer 500 and a second hexagonal tessellated layer 510 are shown. The second hexagonal tessellated layer 510 is on top of the first hexagonal tessellated layer 500. For simplicity, the layer of radiation barrier between the first and second hexagonal tessellated layers is not shown.

[0058] It should be noted also that in the example shown in FIG. 5, the first hexagonal tessellated layer 500 and the second hexagonal tessellated layer 510 are offset (or misaligned) from each other. That is, they do not sit on top of each other such that the walls of the first hexagonal tessellated layer 500 and the walls of the second hexagonal tessellated layer 510 coincide. In other words, the walls of the two adjacent layers do notline up. One reason for the offset of adjacent hexagonal tessellated layers is to minimize thermal conductivity.

[0059] As can be seen in FIG. 5, with the misaligned or offset adjacent hexagonal tessellated layers, the hexagonal cells contact the hexagonal cells of an adjacent layer at a few points on each cell. As shown in FIG. 5, the most contact adjacent hexagonal cells will have with each other is at four points 520 (shown by the circles in FIG. 5). This minimizes contact between the layers to minimize the thermal conductivity between the layers while still maintaining the ability of the layers to carry the structural load. Moreover, note that the offset does not have to exactly bisect the adjacent hexagonal cell. In some examples, the offset can be in any orientation as long as the contact between the layers is substantially reduced.

[0060] To facilitate the offset or misalignment of adjacent layers, some examples of the tessellated insulation structure 330 include an indexing feature or indexing mechanism. The indexing feature is designed to ensure that adjacent hexagonal tessellated layers are properly positioned such that they are offset. In some examples, the indexing feature is also designed to lock each layer in place. In some examples, the indexing feature is a groove on each hexagonal tessellated layer that locks each of the hexagonal tessellated layers in an offset position relative to each of the adjacent ones. In other examples, the indexing feature is one or more of grooves, pins, and divots. In some examples, the radiation barrier layers have holes to allow venting as well as a pin and socket arrangement to allow fastening of adjacent hexagonal tessellated layers to each other. In other examples, the pin and socket arrangement snaps into each other. In other examples, there is a clip that is the same width as two vertical walls of the hexagonal tessellated layer. When the two vertical walls are abutted together, the clip drops down and fastens the two vertical walls together.

[0061] FIG 6 is a cutaway plan view of an example of a curved tessellated layer 600 that in general is more flexible than a hexagonal tessellated layer. As shown in FIG. 6, each of the cells 610 is a curved variation of a square or other polygon.

[0062] FIG. 7 is a flowchart illustrating a method 700 of manufacturing a thermal insulation system for a cryogenic tank that stores cryogenic fluid, according to someexamples. The method 700 includes operation 710 that places a first reflective film around the cryogenic tank. In some examples, an adhesive is used to temporarily keep the first reflective film in place on the surface of the cryogenic tank. In some examples, this adhesive is a pressure sensitive adhesive (PSA). Next, operation 720 places a first tessellated layer on top of the first reflective film. Once again, in some examples this operation 720 uses an adhesive to temporarily hold the first tessellated layer to the first reflective film. Operation 730 wraps a first layer of polymer netting around the cryogenic tank such that the netting is in contact with the first tessellated layer. In this manner the first layer of polymer netting holds in place the first tessellated layer to the first reflective film and both of the first reflective film and the first tessellated layer to the cryogenic tank. In some examples, the thickness of the polymer netting is approximately 7 mil.

[0063] The method 700 then adds additional layers to the thermal insulation system. Operation 740 places a second reflective film over the first layer of polymer netting. In some cases, the second reflective film will adhere to the first layer of polymer netting, but in other situations the adhesive may be used to temporarily hold the second reflective film in place. Next, operation 750 places a second tessellated layer on top of the second reflective film. As before, in some examples the adhesive may be used to temporarily hold the second tessellated layer in place over the second reflective film. Operation 760 wraps a second layer of polymer netting around the cryogenic tank such that the second layer of polymer netting is in contact with the second tessellated layer. This second layer of polymer netting holds in place the second tessellated layer to the second reflective film as well as keeping all the previous layers in place around the cryogenic tank.

[0064] Operation 770 then applies a vacuum shell over the second layer of polymer netting. This hermetically seals the first reflective film, the first tessellated layer, the first layer of polymer netting, the second reflective film, the second tessellated layer, and the second layer of polymer netting within the vacuum shell. The layered structure of reflective films, tessellated layers, and polymer netting provide support to the vacuum shell and allows the vacuum shell to bear a load of up to one atmosphere with collapse. As noted above, the first layer of polymer netting and the second layer of polymer netting allow for the venting of any gas within the layered structure beneath the vacuum shell. More, in some examples the first tessellated layer is offset from the secondtessellated layer such that the second tessellated layer is in contact with the first tessellated layer at only a few points. This serves minimize thermal conductivity between the cryogenic tank and the vacuum shell while still supporting the load on the vacuum shell.Additional Notes

[0065] The following, non-limited examples, detail certain aspects of the present subject matter to solve the challenges and provide the benefits discussed herein, among others.

[0066] Example l is a thermal insulation system for a cryogenic tank, comprising a vacuum shell; and a self-supporting tessellated insulation assembly disposed within the vacuum shell and surrounding the cryogenic tank, the self-supporting tessellated insulation assembly comprising a plurality of layers configured to reduce thermal conduction and support the vacuum shell against external pressure of up to one atmosphere.

[0067] In Example 2, the subject matter of Example 1 includes wherein the self- supporting tessellated insulation assembly comprises a tessellated geometric pattern forming a plurality of void spaces.

[0068] In Example 3, the subject matter of Example 2 includes wherein each of the plurality of void spaces form individual cells, and further comprising holes or grooves at the top or bottom of each of the individual cells to allow gas communication between adjacent individual cells for evacuation or self-evacuation.

[0069] In Example 4, the subject matter of Examples 1-3 includes wherein the plurality of layers further comprises a plurality of rigid insulating structures arranged to form a load-bearing matrix, each layer of the plurality of layers defining a plurality of void spaces, and wherein the plurality of rigid insulating structures are configured to maintain thermal isolation while transferring structural loads.

[0070] In Example 5, the subject matter of Example 4 includes wherein each of layer of the plurality of layers is configured to minimize direct contact points between adjacent layers, thereby reducing thermal conduction while still transferring structural loads through the load-bearing matrix.

[0071] In Example 6, the subject matter of Examples 1-5 includes wherein the plurality of layers are arranged in a repeating sequence with each layer laterally offset relative to an adjacent layer.

[0072] In Example 7, the subject matter of Examples 1-6 includes wherein the self- supporting tessellated insulation assembly performs load-bearing and thermal isolation functions without reliance on supplemental spacer elements, gap maintainers, or interlocking panel assemblies.

[0073] In Example 8, the subject matter of Examples 1-7 includes wherein the self- supporting tessellated insulation assembly further comprises at least two layers of a polymer netting forming individual cells and allow gas communication between adjacent individual cells for evacuation or self-evacuation.

[0074] In Example 9, the subject matter of Examples 7-8 includes wherein the vacuum shell has a thickness of between five-thousandths of an inch and sixty -thousandths of an inch.

[0075] Example 10 is a cryogenic tank insulation apparatus, comprising a cryogenic tank for storing a cryogenic liquid; a hermetically-sealed vacuum shell configured to encase the cryogenic tank; and a self-supporting tessellated insulation assembly disposed between the cryogenic tank and the vacuum shell, the self-supporting tessellated insulation assembly comprising: a plurality of alternating layers, including a plurality of tessellated layers and a plurality of reflective film layers interleaved with the tessellated layers; wherein each of the plurality of tessellated layers defines a plurality of polygonal cells and is arranged in a laterally offset relationship relative to an adjacent tessellated layer such that contact between cells of adjacent layers is limited to discrete points to reduce thermal conduction; and wherein the self-supporting tessellated insulationassembly is configured to both provide thermal insulation to the cryogenic tank and structurally support the vacuum shell against an external load of up to one atmosphere.

[0076] In Example 11, the subject matter of Example 10 includes wherein the vacuum shell has a thickness of between five-thousandths of an inch and sixty -thousandths of an inch.

[0077] In Example 12, the subject matter of Examples 10-11 includes wherein the self- supporting tessellated insulation assembly is flexible and conforms to the outer surface of the cryogenic tank.

[0078] In Example 13, the subject matter of Examples 10-12 includes an indexing mechanism operatively integrated with each of the plurality of tessellated layers to maintain the laterally offset relationship.

[0079] In Example 14, the subject matter of Example 13 includes wherein the indexing mechanism further comprises grooves that lock each of the plurality of tessellated layers in an offset position relative to adjacent layers of the of the plurality of tessellated layers.

[0080] In Example 15, the subject matter of Examples 10-14 includes wherein at least some of the plurality of polygonal cells are configured to contain a gas that cryogenically pumps at a temperature of a cryogenic fluid stored in the cryogenic tank, thereby selfevacuating at least some of the plurality of polygonal cells.

[0081] In Example 16, the subject matter of Examples 10-15 includes wherein the hermetically-sealed vacuum shell is at least one of the following materials: (a) stainless steel; (b) aluminum; (c) titanium; and (d) a polymer metal laminate.

[0082] In Example 17, the subject matter of Examples 10-16 includes wherein each of the plurality of tessellated layers has a cross-sectional shape, and wherein a cross- sectional shape of each of the plurality of polygonal cells is at least one of a triangle, a square, a rectangle, a hexagon, a polygon, or some curved variation of these shapes.

[0083] In Example 18, the subject matter of Examples 10-17 includes wherein each of the plurality of reflective film layers is made of a polymer film with a thin layer of reflective metal deposited on one or more sides, the reflective material being at least one of (a) aluminum; (b) gold; and (c) silver.

[0084] Example 19 is a method of manufacturing a thermal insulation system for a cryogenic tank storing cryogenic fluid, comprising placing a first reflective film that is a radiant barrier in contact with the cryogenic tank; placing a first tessellated layer on top of the first thin reflective film; wrapping a first layer of polymer netting around the cryogenic tank in contact with the first tessellated layer; placing a second reflective film that is a radiant barrier over the first layer of polymer netting; placing a second tessellated layer on top of the second reflective film; wrapping a second layer of polymer netting around the cryogenic tank in contact with the second tessellated layer; applying a vacuum shell over the second layer of polymer netting; and hermetically sealing the first reflective film, the first tessellated layer, the first layer of polymer netting, the second reflective film, the second tessellated layer, and the second layer of polymer netting within the vacuum shell to support the vacuum shell in bearing a load of up to one atmosphere without collapse.

[0085] In Example 20, the subject matter of Example 19 includes using adhesive when placing the first reflective film in contact with the cryogenic tank; and offsetting the first tessellated layer from the second tessellated layer such that the second tessellated layer is in contact with the first tessellated layer at a few points, thereby minimizing thermal conductivity between the cryogenic tank and the vacuum shell while still supporting the load on the vacuum shell; wherein the first layer of polymer netting and the second layer of polymer netting allow venting of gas within the thermal insulation system.

[0086] Example 21 is at least one machine-readable medium including instructions that, when executed by processing circuitry, cause the processing circuitry to perform operations to implement of any of Examples 1-20.

[0087] Example 22 is an apparatus comprising means to implement of any of Examples

[0088] Example 23 is a system to implement of any of Examples 1-20.

[0089] Example 24 is a method to implement of any of Examples 1-20.

[0090] Example 25 is a multilayer insulation structure for insulating a cryogenic tank that stores a cryogenic fluid, comprising: a first polymer reflective layer around the cryogenic tank; a first polymer hexagonal structure in contact with the first polymer reflective layer; and a vacuum shell overlayed on top of the first polymer hexagonal structure for maintaining a hermetic seal within the multilayer insulation structure, wherein the hermetically-sealed multilayer insulation structure supports a load of up to one atmosphere on the vacuum shell without significant deformation or collapse.

[0091] In Example 26, the subject matter of Example 25 includes wherein the vacuum shell has a thickness of between five and sixty -thousandths of an inch.

[0092] In Example 27, the subject matter of Examples 25-26 includes wherein the multilayer insulation structure is flexible such that it conforms to an outer surface of the cryogenic tank.

[0093] In Example 28, the subject matter of Examples 25-27 includes wherein the first polymer reflective layer further comprises a reflective material made from at least one of (a) aluminum; (b) silver; and (c) gold.

[0094] In Example 29, the subject matter of Examples 25-28 includes wherein the first polymer hexagonal structure further comprises individual hexagonal cells arranged in rows and columns or as individual cells.

[0095] In Example 30, the subject matter of Example 29 includes holes or grooves at the top or bottom of each of the individual hexagonal cells to allow gas communication between adjacent individual hexagonal cells for evacuation or self-evacuation.

[0096] In Example 31, the subject matter of Example 30 includes filling at least some of the plurality of individual hexagonal cells with a gas that cryogenically pumps at a temperature of the cryogenic fluid.

[0097] In Example 32, the subject matter of Examples 29-31 includes wherein a cross- sectional shape of each of the individual hexagonal cells is a hexagon.

[0098] In Example 33, the subject matter of Examples 29-32 includes wherein a cross- sectional shape of each of the individual cells is at least one of any regular tessellations of: a triangle, a square, a rectangle, a hexagon, a polygon, or some curved variation of these shapes.

[0099] In Example 34, the subject matter of Examples 25-33 includes wherein the first polymer hexagonal structure is discontiguous.

[0100] In Example 35, the subject matter of Examples 25-34 includes a second polymer reflective layer adjacent to the first polymer hexagonal structure; and a second polymer hexagonal structure adjacent to the second polymer reflective layer.

[0101] In Example 36, the subject matter of Example 35 includes wherein the first polymer hexagonal structure and the second polymer hexagonal structure are offset from each other such that walls of the first polymer hexagonal structure and the second polymer hexagonal structure do not line up with each other.

[0102] In Example 37, the subject matter of Example 36 includes an indexing feature designed to lock each layer in place and ensure offsetting of adjacent layers of the first polymer hexagonal structure and the second polymer hexagonal structure.

[0103] In Example 38, the subject matter of Example 37 includes wherein the indexing feature further comprises one of more of grooves, pins, and divots.

[0104] In Example 39, the subject matter of Examples 35-38 includes wherein the first polymer hexagonal structure and the second polymer hexagonal structure is designed to absorb shock in crash situations, thereby protecting the tank from rupturing.

[0105] Example 40 is a method of manufacturing a multilayer insulation structure for a cryogenic tank storing cryogenic fluid, comprising placing a first thin reflective film that is a radiant barrier in contact with the cryogenic tank; placing a first lightweight hexagonal structure on top of the first thin reflective film; placing a second thin reflective film that is a radiant barrier over the first lightweight hexagonal structure;placing a second lightweight hexagonal structure on top of the second thin reflective film; applying a thin vacuum shell over the second lightweight hexagonal structure; and hermetically sealing the first thin reflective film, the first lightweight hexagonal structure, second thin reflective film, and the second lightweight hexagonal structure within the thin vacuum shell such that the first lightweight hexagonal structure and the second lightweight hexagonal structure support the thin vacuum shell to bear a load of up to one atmosphere without collapsing.

[0106] In Example 41, the subject matter of Example 40 includes, wherein the multilayer insulation structure is flexible to allow conforming to an outer surface of the cryogenic tank.

[0107] In Example 42, the subject matter of Example 41 includes, wrapping the multilayer insulation structure around an outside of the cryogenic tank.

[0108] In Example 43, the subject matter of Examples 40-42 includes wherein the first lightweight hexagonal structure and the second lightweight hexagonal structure further comprise a plurality of individual hexagonal cells configured to support the thin vacuum shell.

[0109] In Example 44, the subject matter of Example 43 includes filling at least some of the plurality of individual hexagonal cells with a gas that cryogenically pumps at a temperature of the cryogenic fluid.

[0110] In Example 45, the subject matter of Example 44 includes wherein the gas is carbon dioxide, and the cryogenic fluid is liquid hydrogen, and the carbon dioxide gas is turned into a solid at the temperature of the liquid hydrogen in order to evacuate the plurality of individual hexagonal cells filled with carbon dioxide.[OHl] In Example 46, the subject matter of Examples 40-45 includes positioning the second lightweight hexagonal structure such that it is offset from the first lightweight hexagonal structure such that the second lightweight hexagonal structure is only in contact with the first lightweight hexagonal structure at a few points, thereby minimizing thermal conductivity between the cryogenic tank and the thin vacuum shell.

[0112] In Example 47, the subject matter of Example 46 includes wherein the second lightweight hexagonal structure is offset from the first lightweight hexagonal structure using an indexing feature that ensures that the second lightweight hexagonal structure and the first lightweight hexagonal structure are offset from each other.

[0113] In Example 48, the subject matter of Example 47 includes wherein the indexing feature is a groove, pin, or divot.

[0114] In Example 49, the subject matter of Examples 43-48 includes wherein each of the plurality of individual hexagonal cells has a cross-sectional shape that facilitates the multilayer insulation structure being able to conform to an outside surface of the cryogenic tank.

[0115] In Example 50, the subject matter of Example 49 includes wherein the cross- sectional shape is a hexagon.

[0116] In Example 51, the subject matter of Examples 43-50 includes incorporating a mechanism for gas communication between the plurality of individual hexagonal cells.

[0117] In Example 52, the subject matter of Example 51 includes making holes or grooves at the top or bottom of each of the individual hexagonal cells.

[0118] In Example 53, the subject matter of Examples 50-52 includes wherein the thin vacuum shell is made from stainless steel.

[0119] In Example 54, the subject matter of Examples 50-53 includes wherein the thin vacuum shell is made from a combination of stainless steel and fiberglass.

[0120] In Example 55, the subject matter of Examples 50-54 includes wherein the first lightweight hexagonal structure is made from a high-performance plastic and further comprising sputter coating the high-performance plastic with a thin aluminum coating to enhance radiation barrier properties.

[0121] In Example 56, the subject matter of Example 55 includes wherein the high- performance plastic is polyetherimide.

[0122] In Example 57, the subject matter of Examples 50-56 includes wherein the first thin reflective film is made from a polyimide film with a thin layer of aluminum deposited on either side.

[0123] Example 58 is a lightweight multilayer material for thermal insulation of a cryogenic tank, comprising a plurality of hexagonal structures having individual cells; a plurality of thin radiation barriers; a thin vacuum shell; and an indexing feature on the plurality of hexagonal structures to ensure that adjacent ones of the plurality of hexagonal structures are offset from each other; wherein the plurality of thin radiation barriers and the plurality of hexagonal structures are positioned in an alternating fashion on top of each other starting with a thin radiation barrier in contact with an outer surface of the cryogenic tank and ending with the thin vacuum shell on top of a hexagonal structure that is outermost from the outer surface of the cryogenic tank; wherein the lightweight multilayer material is flexible and conforms to the outer surface of the cryogenic tank.

[0124] In Example 59, the subject matter of Example 58 includes wherein the thin vacuum shell hermetically seals the lightweight multilayer material.

[0125] In Example 60, the subject matter of Example 59 includes wherein each of the plurality of hexagonal structures supports the thin vacuum shell such that the thin vacuum shell can sustain a load of up to one atmosphere without compressing.

[0126] In Example 61, the subject matter of Example 60 includes wherein the thin vacuum shell is at least one of the following materials: (a) stainless steel; (b) aluminum; and (c) titanium.

[0127] In Example 62, the subject matter of Examples 58-61 includes wherein each of the plurality of hexagonal structures has a cross-sectional shape, and wherein a cross- sectional shape of each of the individual cells is at least one of any regular tessellations of: a triangle, a square, a rectangle, a hexagon, a polygon, or some curved variation of these shapes.

[0128] In Example 63, the subject matter of Examples 58-62 includes wherein each of the thin radiation barriers is made of a polyimide film with a thin layer of aluminumdeposited on either side and having a thickness of approximately one-thousandth of an inch.

[0129] In Example 64, the subject matter of Examples 58-63 includes wherein the indexing feature further comprises grooves that lock each of the plurality of hexagonal structures in an offset position relative to each the adjacent ones.

[0130] Example 65 is at least one machine-readable medium including instructions that, when executed by processing circuitry, cause the processing circuitry to perform operations to implement of any of Examples 25-65.

[0131] Example 66 is an apparatus comprising means to implement of any of Examples 25-65.

[0132] Example 67 is a system to implement of any of Examples 25-65.

[0133] Example 68 is a method to implement of any of Examples 25-65.

[0134] Examples of the system and method can include every combination and permutation of the various system components and the various method processes, wherein one or more instances of the method and / or processes described herein can be performed asynchronously (e.g., sequentially), concurrently (e.g., in parallel), or in any other suitable order by and / or using one or more instances of the systems, elements, and / or entities described herein.

[0135] As a person skilled in the art will recognize from the previous detailed description and from the figures and claims, modifications and changes can be made to the examples of the technology disclosed herein without departing from the scope of this technology defined in the following claims.

[0136] The above-detailed description includes references to the accompanying drawings, which form a part of the detailed description. The drawings show, by way of illustration, specific embodiments in which the technology can be practiced. These embodiments are also referred to herein as “examples.” Such examples can include elements in addition to those shown or described. However, the present inventors alsocontemplate examples in which only those elements shown or described are provided. Moreover, the present inventors also contemplate examples using any combination or permutation of those elements shown or described (or one or more aspects thereof), either with respect to a particular example (or one or more aspects thereof), or with respect to other examples (or one or more aspects thereof) shown or described herein.

[0137] In the event of inconsistent usages between this document and any documents so incorporated by reference, the usage in this document controls.

[0138] In this document, the terms “a” or “an” are used, as is common in patent documents, to include one or more than one, independent of any other instances or usages of “at least one” or “one or more.” In this document, the term “or” is used to refer to a nonexclusive or, such that “A or B” includes “A but not B,” “B but not A,” and “A and B,” unless otherwise indicated. In this document, the terms “including” and “in which” are used as the plain-English equivalents of the respective terms “comprising” and “wherein.” Also, in the following claims, the terms “including” and “comprising” are open-ended, that is, a system, device, article, composition, formulation, or process that includes elements in addition to those listed after such a term in a claim are still deemed to fall within the scope of that claim. Moreover, in the following claims, the terms “first,” “second,” and “third,” etc. are used merely as labels, and are not intended to impose numerical requirements on their objects.

[0139] The above description is intended to be illustrative, and not restrictive. For example, the above-described examples (or one or more aspects thereof) may be used in combination with each other. Other embodiments can be used, such as by one of ordinary skill in the art upon reviewing the above description. The Abstract is provided to comply with 37 C.F.R. § 1.72(b), to allow the reader to quickly ascertain the nature of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims. Also, in the above Detailed Description, various features may be grouped together to streamline the disclosure. This should not be interpreted as intending that an unclaimed disclosed feature is essential to any claim. Rather, inventive subject matter may lie in less than all features of a particular disclosed embodiment. Thus, the following claims are hereby incorporated into the Detailed Description as examples or embodiments, with each claim standing onits own as a separate embodiment, and it is contemplated that such embodiments can be combined with each other in various combinations or permutations. The scope of the technology should be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled.

Claims

CLAIMSWhat is Claimed is:

1. A thermal insulation system for a cryogenic tank, comprising: a vacuum shell; and a self-supporting tessellated insulation assembly disposed within the vacuum shell and surrounding the cryogenic tank, the self-supporting tessellated insulation assembly comprising a plurality of layers configured to reduce thermal conduction and support the vacuum shell against external pressure of up to one atmosphere.

2. The thermal insulation system of claim 1, wherein the self-supporting tessellated insulation assembly comprises a tessellated geometric pattern forming a plurality of void spaces.

3. The thermal insulation system of claim 2, wherein each of the plurality of void spaces form individual cells, and further comprising holes or grooves at the top or bottom of each of the individual cells to allow gas communication between adjacent individual cells for evacuation or self-evacuation.

4. The thermal insulation system of claim 1, wherein the plurality of layers further comprises a plurality of rigid insulating structures arranged to form a load-bearing matrix, each layer of the plurality of layers defining a plurality of void spaces, and wherein the plurality of rigid insulating structures are configured to maintain thermal isolation while transferring structural loads.

5. The thermal insulation system of claim 4, wherein each of layer of the plurality of layers is configured to minimize direct contact points between adjacent layers, thereby reducing thermal conduction while still transferring structural loads through the loadbearing matrix.

6. The thermal insulation system of claim 1, wherein the plurality of layers are arranged in a repeating sequence with each layer laterally offset relative to an adjacent layer.

7. The thermal insulation system of claim 1, wherein the self-supporting tessellated insulation assembly performs load-bearing and thermal isolation functionswithout reliance on supplemental spacer elements, gap maintainers, or interlocking panel assemblies.

8. The thermal insulation system of claim 1, wherein the self-supporting tessellated insulation assembly further comprises at least two layers of a polymer netting forming individual cells and allow gas communication between adjacent individual cells for evacuation or self-evacuation.

9. The thermal insulation system of claim 1, wherein the vacuum shell has a thickness of between five-thousandths of an inch and sixty -thousandths of an inch.

10. A cryogenic tank insulation apparatus, comprising: a cryogenic tank for storing a cryogenic liquid; a hermetically-sealed vacuum shell configured to encase the cryogenic tank; and a self-supporting tessellated insulation assembly disposed between the cryogenic tank and the vacuum shell, the self-supporting tessellated insulation assembly comprising: a plurality of alternating layers, including a plurality of tessellated layers and a plurality of reflective film layers interleaved with the tessellated layers; wherein each of the plurality of tessellated layers defines a plurality of polygonal cells and is arranged in a laterally offset relationship relative to an adjacent tessellated layer such that contact between cells of adjacent layers is limited to discrete points to reduce thermal conduction; and wherein the self-supporting tessellated insulation assembly is configured to both provide thermal insulation to the cryogenic tank and structurally support the vacuum shell against an external load of up to one atmosphere.

11. The cryogenic tank insulation apparatus of claim 10, wherein the vacuum shell has a thickness of between five-thousandths of an inch and sixty -thousandths of an inch.

12. The cryogenic tank insulation apparatus of claim 10, wherein the self- supporting tessellated insulation assembly is flexible and conforms to the outer surface of the cryogenic tank.

13. The cryogenic tank insulation apparatus of claim 10, further comprising an indexing mechanism operatively integrated with each of the plurality of tessellated layers to maintain the laterally offset relationship.

14. The cryogenic tank insulation apparatus of claim 13, wherein the indexing mechanism further comprises grooves that lock each of the plurality of tessellated layers in an offset position relative to adjacent layers of the of the plurality of tessellated layers.

15. The cryogenic tank insulation apparatus of claim 10, wherein at least some of the plurality of polygonal cells are configured to contain a gas that cryogenically pumps at a temperature of a cryogenic fluid stored in the cryogenic tank, thereby selfevacuating at least some of the plurality of polygonal cells.

16. The cryogenic tank insulation apparatus of claim 10, wherein the hermetically- sealed vacuum shell is at least one of the following materials: (a) stainless steel; (b) aluminum; (c) titanium; and (d) a polymer-metal laminate.

17. The cryogenic tank insulation apparatus of claim 10, wherein each of the plurality of tessellated layers has a cross-sectional shape, and wherein a cross-sectional shape of each of the plurality of polygonal cells is at least one of: a triangle, a square, a rectangle, a hexagon, a polygon, or some curved variation of these shapes.

18. The cryogenic tank insulation apparatus of claim 10, wherein each of the plurality of reflective film layers is made of a polymer film with a thin layer of reflective metal deposited on one or more sides, the reflective material being at least one of: (a) aluminum; (b) gold; and (c) silver.

19. A method of manufacturing a thermal insulation system for a cryogenic tank storing cryogenic fluid, comprising: placing a first reflective film that is a radiant barrier in contact with the cryogenic tank; placing a first tessellated layer on top of the first thin reflective film; wrapping a first layer of polymer netting around the cryogenic tank in contact with the first tessellated layer; placing a second reflective film that is a radiant barrier over the first layer of polymer netting;placing a second tessellated layer on top of the second reflective film; wrapping a second layer of polymer netting around the cryogenic tank in contact with the second tessellated layer; applying a vacuum shell over the second layer of polymer netting; and hermetically sealing the first reflective film, the first tessellated layer, the first layer of polymer netting, the second reflective film, the second tessellated layer, and the second layer of polymer netting within the vacuum shell to support the vacuum shell in bearing a load of up to one atmosphere without collapse.

20. The method of claim 19, further comprising: using adhesive when placing the first reflective film in contact with the cryogenic tank; and offsetting the first tessellated layer from the second tessellated layer such that the second tessellated layer is in contact with the first tessellated layer at a few points, thereby minimizing thermal conductivity between the cryogenic tank and the vacuum shell while still supporting the load on the vacuum shell; wherein the first layer of polymer netting and the second layer of polymer netting allow venting of gas within the thermal insulation system.

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