A high-efficiency self-pressurization system for converting liquid hydrogen into high-pressure gaseous hydrogen based on a non-powered device

Abstract

This invention relates to a highly efficient self-pressurization system for converting liquid hydrogen into high-pressure gaseous hydrogen using a non-powered device. The system includes a liquid hydrogen heating and pressurization unit and a non-powered filling and displacement unit for high-pressure hydrogen. The heating and pressurization unit introduces external heat through a heat exchanger within a sealed liquid hydrogen storage tank, raising the temperature and pressure of the liquid hydrogen, while simultaneously connecting to an external cold energy recovery device to reclaim cold energy. The filling and displacement unit, via a non-powered filling pipe and valve connecting the storage tank and the hydrogen recovery device, uses filler material located within the hydrogen recovery device to enter the storage tank under gravity or magnetic force, directly displacing an equal volume of high-pressure gaseous hydrogen into the hydrogen recovery device. Compared to existing technologies, this invention has a simple structure, is easy to operate, and can efficiently, safely, and with low energy consumption obtain high-pressure gaseous hydrogen without the need for an external driving device.

Description

Technical Field

[0001] This invention relates to the field of liquid hydrogen utilization technology, and in particular to a highly efficient self-pressurization system for converting liquid hydrogen into high-pressure gaseous hydrogen without a power source. Background Technology

[0002] Hydrogen energy is considered one of the most promising secondary energy sources in the 21st century due to its cleanliness, high efficiency, and wide availability. Liquid hydrogen (LH2), as an important carrier of hydrogen energy, has extremely high volumetric energy density and demonstrates significant advantages in hydrogen storage and long-distance transportation.

[0003] However, the vast majority of end-use devices, such as hydrogen fuel cell engines, hydrogen internal combustion engines, and hydrogen refueling stations, require high-pressure gaseous hydrogen. Therefore, efficiently and safely converting stored cryogenic liquid hydrogen into high-pressure gaseous hydrogen is an indispensable and crucial link in the hydrogen energy application chain.

[0004] Currently, the mainstream technologies for converting liquid hydrogen to high-pressure gaseous hydrogen mainly rely on external power devices, which have limitations, such as reliance on external compressors, high energy consumption, and system complexity. The most common solution is to use a liquid hydrogen pump or a high-pressure hydrogen compressor. This solution first requires vaporizing the liquid hydrogen into atmospheric or low-pressure hydrogen gas, and then using a compressor to pressurize it. The compressor and its drive equipment not only have high energy consumption (accounting for more than 10% of the total hydrogen energy), significantly reducing the overall system efficiency, but also make the system complex, bulky, and costly to maintain, making it particularly unsuitable for space- and weight-sensitive applications (such as vehicle environments). If a traditional self-pressurization method is adopted, it is inefficient and has poor controllability. This method utilizes some liquid hydrogen to absorb ambient heat in a sealed storage tank to vaporize and generate pressure (self-pressurization), and then discharges the remaining liquid hydrogen. However, this method has a slow vaporization rate, slow pressure increase, and is heavily dependent on ambient temperature, resulting in poor stability and controllability. The discharged liquid hydrogen still needs to be heated by an external evaporator to become a usable gas, making the entire process inefficient and inefficient in terms of energy utilization. At the same time, there is still a serious problem of wasting the cold energy of liquid hydrogen. Liquid hydrogen is stored at an extremely low temperature (-253 ℃) and contains a huge amount of cold energy. If it cannot be used properly, it will cause a certain amount of energy waste.

[0005] Patent document CN114877247A discloses a liquid hydrogen supply system for high-pressure fuel cells. This system recovers waste heat generated by the fuel cell system and heats the liquid hydrogen in the intermediate stage of the heat exchanger, causing it to vaporize and pressurize within a cryogenic high-pressure hydrogen storage container. However, this pressurization process heavily relies on the continuous operation and waste heat output of the fuel cell as an external heat source. Once disconnected from the fuel cell system, or under conditions of insufficient waste heat during startup or at low loads, the system cannot function effectively, lacking the ability to independently and actively generate high-pressure hydrogen. Its application is strictly limited to specific coupled systems with a stable waste heat source.

[0006] Patent document CN115013721A discloses a high-efficiency liquid hydrogen refueling station system. While this solution mentions utilizing the cold energy of liquid hydrogen to condense BOG (evaporated gas), its core power for achieving high-pressure hydrogen supply still relies on external power equipment, including a low-pressure BOG compressor, a low-pressure liquid hydrogen pump, and a high-pressure liquid hydrogen pump. Essentially, this solution is still an evolution of the "liquid hydrogen pump / compressor" technology route, and its system energy consumption, complexity, and dependence on highly reliable external power equipment have not been fundamentally resolved.

[0007] In summary, existing technologies share a common core deficiency and contradiction: they cannot achieve rapid and controllable self-pressurization of liquid hydrogen without relying on external heat sources (such as waste heat from fuel cells) or external power equipment (such as various pumps and compressors), while simultaneously and efficiently recovering and utilizing the enormous cold energy generated during the liquid hydrogen phase change process. Therefore, there is an urgent need in this field for a novel technological solution that can eliminate dependence on specific external energy sources or complex power equipment, achieving an inherent synergy and efficient unification of self-pressurization of liquid hydrogen and cold energy recovery and utilization. This would broaden the application boundaries of liquid hydrogen high-pressure technology and improve system energy efficiency and reliability. Summary of the Invention

[0008] The purpose of this invention is to overcome the shortcomings of the existing technology by providing a highly efficient self-pressurization system for converting liquid hydrogen into high-pressure gaseous hydrogen without a power source. By eliminating the reliance on external heat sources such as waste heat from fuel cells or external power equipment such as compressors / pumps, the system utilizes the self-heating vaporization of liquid hydrogen in a cryogenic high-pressure hydrogen storage container to generate high pressure. In this process, cold energy is efficiently recovered for system heat dissipation, thereby achieving the synergy of self-pressurization without external force and cold energy utilization. This significantly simplifies the system structure, reduces energy consumption and cost, stabilizes the hydrogen supply pressure, improves overall efficiency, and broadens the application scenarios of high-pressure liquid hydrogen supply systems.

[0009] The objective of this invention can be achieved through the following technical solutions: This invention provides a highly efficient self-pressurization system for converting liquid hydrogen into high-pressure gaseous hydrogen without a power source, comprising a liquid hydrogen heating and pressurization unit and a high-pressure hydrogen filling and displacement unit without a power source. The liquid hydrogen heating and pressurization unit includes a sealed liquid hydrogen storage tank, a heat exchange device installed inside the liquid hydrogen storage tank, and an external cold energy utilization device connected to the liquid hydrogen storage tank. The heat exchange device is used to introduce external heat into the liquid hydrogen storage tank to heat and pressurize the liquid hydrogen therein. The non-powered filling and displacement high-pressure hydrogen unit includes a non-powered filling pipeline, valves, filling material, and hydrogen utilization device; The non-powered filling pipeline connects the outlet of the liquid hydrogen storage tank to the inlet of the hydrogen utilization device, and the valve is installed on the non-powered filling pipeline to control its on / off state. The filling material is disposed inside the hydrogen utilization device and can enter the liquid hydrogen storage tank through the valve and the non-powered filling pipeline under the drive of any one of gravity, magnetic force, electric field force, pressure difference force, ejection effect, and centrifugal force, so as to displace an equal volume of high-pressure gaseous hydrogen into the hydrogen utilization device.

[0010] Furthermore, the liquid hydrogen storage tank is a double-layered container with a vacuum insulation layer.

[0011] Furthermore, the heat exchange device is a heat exchanger located inside the liquid hydrogen storage tank. The heat exchanger is one of a solid heat conductor, a fluid convection heat exchanger, or a radiation heat exchanger, or one of an external heating heat exchanger, a tank body heat leakage heat exchanger, or a tank insulation vacuum failure heat exchanger. The pipes of the heat exchange device are connected to the external cold energy utilization device.

[0012] Specifically, in the prior art, an externally heated heat exchanger refers to a heat exchange device that transfers heat to the interior of a liquid hydrogen storage tank through an external active heat source such as an electric heater or an infrared radiator, in order to accelerate the vaporization and pressurization of liquid hydrogen.

[0013] Specifically, in the prior art, a heat exchanger for a liquid hydrogen storage tank body refers to a heat exchange method that utilizes the unavoidable residual heat leakage of the vacuum insulation layer of the liquid hydrogen storage tank itself or the natural heat conduction of structures such as heat-conducting support components, so that the liquid hydrogen slowly absorbs heat from the environment and vaporizes.

[0014] Specifically, in the prior art, a heat exchanger for a storage tank with vacuum failure refers to a heat exchange device that significantly reduces the insulation performance by controlling the disruption of the vacuum state of the liquid hydrogen storage tank jacket (such as opening a vacuum valve or introducing gas), allowing a large amount of ambient heat to be transferred into the tank to achieve rapid vaporization.

[0015] Furthermore, the external cold energy utilization device can further process the cold energy transmitted from the liquid hydrogen storage tank. The external cold energy utilization device is a cryogenic heat exchanger, a cold energy power generation device, or a cryogenic refrigeration device that is connected to the heat exchange device via a pipeline.

[0016] Furthermore, the filler is a difficult-to-compress fluid or solid particles; The solid is made of a material that is insensitive to hydrogen embrittlement and has low-temperature toughness. The solid material has a shape including spheres, cubes, cones or irregular shapes, and a size range of 0.001 mm to 1000 mm. The incompressible fluids include water, mercury, alcohol, and mineral oils such as hydraulic oil, lubricating oil, and fuel oils (such as gasoline and diesel). Vegetable oils include castor oil, olive oil, and rapeseed oil. Synthetic oils include silicone oil and fluorinated liquids (such as fluorocarbons). Other common liquids include glycerol and ethylene glycol.

[0017] Furthermore, the valve is connected to the non-powered filling pipe via a welded or detachable joint.

[0018] Furthermore, the non-powered filling pipe is made of a hydrogen embrittlement resistant material. One end of the non-powered filling pipe is sealed to the outlet of the liquid hydrogen storage tank through a high-pressure connector, and the other end is sealed to the inlet of the hydrogen utilization device through the valve.

[0019] In one embodiment of the present invention, the heat exchange device includes a vacuum breaking valve disposed in the vacuum insulation jacket of the liquid hydrogen storage tank, the vacuum breaking valve being used to controllably break the vacuum insulation state of the liquid hydrogen storage tank.

[0020] As one embodiment of the present invention, the heat exchange device includes an electric heater, an infrared heater, or a microwave heater that is attached to the inner or outer wall or the outer side of the inner layer of the liquid hydrogen storage tank.

[0021] Furthermore, the hydrogen utilization device is one of the following: a hydrogen fuel cell power generation device, a hydrogen internal combustion engine, a hydrogen storage and refueling system of a hydrogen refueling station, or an on-board power system capable of utilizing or collecting hydrogen.

[0022] Compared with the prior art, the present invention has the following beneficial effects: 1. High-efficiency recovery of liquid hydrogen cold energy: Through the rational design and configuration of heat exchange devices and external cold energy utilization devices, the cold energy of liquid hydrogen is fully utilized to achieve the heating and pressurization of hydrogen, effectively reducing the cold energy loss during the storage and utilization of liquid hydrogen and improving the utilization efficiency of liquid hydrogen.

[0023] 2. Non-powered filling and replacement: The high-pressure hydrogen unit is used for non-powered filling and replacement. No additional power equipment or energy input is required to recover hydrogen from the liquid hydrogen storage tank to the utilization device, which reduces the energy consumption and operating cost of the device, while simplifying the system structure and improving the reliability and safety of the device.

[0024] 3. High safety: By setting up key components such as heat exchange devices and valves, precise control of the hydrogen transportation process is achieved, ensuring the safe operation of the entire system.

[0025] 4. Precise control: By rationally designing the structural dimensions and position of the packing material, the flow and mixing state of hydrogen can be effectively adjusted, improving the efficiency and quality of hydrogen delivery and achieving precise control over the liquid hydrogen heating and pressurization process.

[0026] 5. Wide range of applications: The device of the present invention can be used in a variety of liquid hydrogen storage and utilization scenarios, such as liquid hydrogen refueling stations, fuel cell power generation systems, hydrogen combustion devices, etc., and has broad application prospects and market potential. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of the efficient self-pressurization system for converting liquid hydrogen into high-pressure gaseous hydrogen using a highly efficient heat exchange method, as shown in Example 1.

[0028] Figure 2 This is a schematic diagram of the structure of the non-powered high-pressure hydrogen replacement in Example 2.

[0029] Figure 3 This is a schematic diagram of the high-efficiency self-pressurization system structure in Example 3, which reduces the vacuum insulation performance.

[0030] Among them, 1-liquid hydrogen storage tank, 2-heat exchange device, 3-external cold energy utilization device, 4-valve, 5-non-powered filling pipeline, 6-filling material, 7-hydrogen utilization device, 8-liquid hydrogen. Detailed Implementation

[0031] The process apparatus for the efficient self-pressurization system for converting liquid hydrogen into high-pressure gaseous hydrogen in this invention includes a liquid hydrogen heating and pressurization unit and a non-powered filling and displacement high-pressure hydrogen unit. The liquid hydrogen heating and pressurization unit includes a sealed liquid hydrogen storage tank for storing liquid hydrogen, a heat exchange device installed inside the liquid hydrogen storage tank or on both sides of the tank cavity, and an external cold energy utilization device connected to the liquid hydrogen storage tank. The non-powered filling and replacement high-pressure hydrogen unit includes a valve, a non-powered filling pipeline, filling material, and a hydrogen utilization device. The hydrogen utilization device is connected to the liquid hydrogen storage tank through the non-powered filling pipeline. The valve is located at the connection between the non-powered filling pipeline and the hydrogen utilization device. The filling material is in all or part of the volume inside the hydrogen utilization device. The liquid hydrogen storage tank is a sealed container used to store cryogenic liquid hydrogen. It adopts a vacuum insulation structure design, with an inner tank for storing liquid hydrogen and an outer tank for providing insulation protection. The inner and outer layers are evacuated. High vacuum insulation, stacked insulation, and vacuum multilayer insulation are used to reduce the loss of cold energy during the liquid hydrogen storage process. The heat exchange device is located inside the liquid hydrogen storage tank or on both sides of the inner layer. It can achieve heat exchange by contacting liquid hydrogen or by contacting liquid hydrogen through the wall. It can adopt a spiral tube or serpentine tube structure to increase the heat exchange area and improve the heat exchange efficiency, thereby more effectively heating and pressurizing the low-temperature liquid hydrogen to high-pressure gaseous hydrogen. Alternatively, it can utilize vacuum failure, that is, the decrease in the vacuum insulation performance of the liquid hydrogen storage tank, which leads to heat exchange with the outside, or use external infrared, microwave or other heating methods to achieve the evaporation of liquid hydrogen in the sealed container and convert it into high-pressure gaseous hydrogen. In practical implementation, the external cold energy utilization device is connected to the liquid hydrogen storage tank for further processing the hydrogen output from the liquid hydrogen storage tank. It employs a high-efficiency plate-fin heat exchanger or a shell-and-tube heat exchanger with strong pressure resistance, possessing high heat exchange efficiency and good adaptability to meet heat exchange requirements under different operating conditions. In a preferred embodiment, the external heat exchanger is a plate-and-shell heat exchanger, with its shell made of carbon steel and the plate bundles made of stainless steel, combining high-efficiency heat exchange with pressure resistance, suitable for the system's operating pressure range. In specific implementation, the valve in the non-powered filling and replacement high-pressure hydrogen unit is used to control the opening and closing of the non-powered filling pipeline. The non-powered filling pipeline is used to transport hydrogen from the liquid hydrogen storage tank to the hydrogen utilization device. The filling material is placed in the hydrogen utilization device. After the valve is opened under certain conditions or by manual operation, the filling material promotes the flow and mixing of hydrogen through the non-powered filling pipeline. In practical implementation, the valve can be a normally closed, zero-leakage, explosion-proof high-pressure valve, connected to the pipeline with high pressure matching, such as using double compression fittings, welded fittings, or high-pressure flanges. It can open or close the non-powered filling pipeline under certain conditions or manual operation, ensuring rapid system response and precise control.

[0032] In practical implementation, the non-powered filling pipeline connects the outlet of the liquid hydrogen storage tank to the inlet of the hydrogen utilization device. It can utilize existing hydrogen embrittlement-resistant materials, such as hydrogen-resistant alloys, to ensure long-term safe operation under high-pressure hydrogen conditions. Its inner diameter should be optimized based on the system flow rate and the maximum diameter of the irregular filler material to balance flow velocity and pressure loss, achieving efficient filling. The pipeline wall thickness must ensure its working pressure rating is not less than 1.5 times the maximum working pressure of the system. Connections to the storage tank, valves, and hydrogen utilization device can use high-pressure double-ferrule fittings or welding connections with high sealing reliability to ensure zero leakage at the interfaces. The pipeline laying path should be short and straight, minimizing the number of bends. If bends are necessary, large-curvature bends can be used to reduce flow resistance.

[0033] In practice, the filler material is used to fill all or part of the volume of the hydrogen utilization device, and is composed of solids of different specifications, such as conical or spherical shapes; or incompressible fluids, such as mercury, water, or alcohol. The solid filler material should be selected from materials that are not sensitive to hydrogen embrittlement, have good low-temperature toughness, sufficient strength and hardness, and are not easily worn or pulverized under the impact of airflow, so as to ensure the long-term stability of the filler layer and ensure the structural integrity and safety of the filler material under long-term immersion in high-pressure hydrogen or low-temperature liquid hydrogen.

[0034] In practical implementation, the hydrogen utilization device is connected to a non-powered filling pipeline to receive hydrogen transported through the pipeline and convert it into electrical and thermal energy, thus achieving efficient utilization of hydrogen. A hydrogen utilization device refers to equipment or systems that require high-pressure gaseous hydrogen as a raw material, fuel, or working medium. Specific forms include, but are not limited to: hydrogen fuel cell power generation devices, such as vehicle power systems and stationary power stations; hydrogen combustion devices, such as hydrogen internal combustion engines, hydrogen gas turbines, and industrial burners; chemical and metallurgical equipment, such as hydrogen refueling reactors, semiconductor manufacturing equipment, and metal heat treatment furnaces; hydrogen energy infrastructure, such as hydrogen storage and refueling systems at hydrogen refueling stations; and aerospace and special-purpose equipment. In practical implementation, the device of the present invention integrates the liquid hydrogen storage tank, heat exchange device, external cold energy utilization device, valve, non-powered filling pipeline, filling material, and hydrogen utilization device into a complete system through reasonable design. By reasonably designing and optimizing the structural dimensions of the multi-scale difficult-to-compressible filling material in the non-powered device, as well as the positions of key components such as valves and heat exchange devices, the safety, accuracy, and efficiency of the liquid hydrogen heating and pressurization process are ensured.

[0035] The technical mechanism of this invention mainly revolves around the synergistic effect of three core physical processes: heating and pressurizing liquid hydrogen in a confined space, efficient recovery of cold energy, and gas replacement without external mechanical power.

[0036] This invention stores liquid hydrogen in a vacuum-insulated, sealed tank. Through a heat exchanger inside the tank, the system efficiently transfers heat from the external environment, or external heat flow introduced in a controlled manner, to the cryogenic liquid hydrogen. Upon absorbing heat, the liquid hydrogen undergoes a phase change, transforming into gaseous hydrogen. Because the tank is completely sealed, the hydrogen produced by vaporization cannot escape freely, leading to an increase in the number and kinetic energy of gas molecules inside the tank, thus causing a continuous and stable rise in internal pressure. This process converts thermal energy into pressure potential energy, eliminating the need for traditional high-pressure compressors to convert cryogenic, low-pressure liquid hydrogen into high-pressure gaseous hydrogen. Simultaneously, the external cold energy utilization device connected to the tank is essentially a heat exchange system that utilizes the enormous latent and sensible heat load absorbed during the liquid hydrogen's phase change and heating process to generate significant cold energy. Specifically, when liquid hydrogen vaporizes, it takes heat from external heat sources or heat exchange media, which cools or even liquefies these media. This allows for the effective recovery of liquid hydrogen cold energy that might otherwise be wasted, enabling its use in other applications such as air liquefaction, cryogenic freezing, and thermoelectric power generation, thus significantly improving the overall energy utilization efficiency of the entire system.

[0037] Once the internal pressure of the liquid hydrogen storage tank reaches the required high pressure through the aforementioned self-pressurization process, the system initiates the gas transfer step. This eliminates the need for a hydrogen compressor that consumes electrical or mechanical energy. Instead, it relies on a separate, filled hydrogen utilization device. This device is connected to the gas phase space of the high-pressure liquid hydrogen storage tank via a pipe equipped with a controllable valve. When hydrogen needs to be transferred, the valve opens. Under the influence of non-mechanical driving forces such as gravity or magnetism, the solid filler or incompressible fluid pre-placed in the hydrogen utilization device flows through the pipe to the bottom of the high-pressure liquid hydrogen storage tank. The entry of this filler occupies part of the bottom volume of the tank. According to the basic principles of fluid mechanics, in a closed and interconnected container system, the entry of incompressible filler into the tank will inevitably force out an equal volume of high-pressure gaseous hydrogen from the gas phase space at the top of the tank. Driven by the pressure difference, the expelled high-pressure hydrogen naturally flows back through the connecting pipe into the hydrogen utilization device that originally contained the filler, thus completing the lossless transfer of high-pressure hydrogen. The entire replacement process is driven solely by the potential energy difference or magnetic force of the filler material itself, achieving true power delivery without external force.

[0038] In summary, the technical mechanism of this invention is to organically integrate the three stages of liquid hydrogen heating and pressurization, cold energy recovery, and equal-volume displacement transportation through an integrated design. The self-pressurization stage utilizes the phase change principle to generate high pressure in a confined space, the cold energy recovery stage improves economic efficiency, and the non-powered displacement stage utilizes the principle of physical displacement to transfer high-pressure gas. These three elements work together to form a simple, energy-efficient, and safe operating system for converting liquid hydrogen into high-pressure gaseous hydrogen.

[0039] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments. Component models, material names, connection structures, control methods, algorithms, and other features not explicitly described in this technical solution are considered common technical features disclosed in the prior art.

[0040] The technical solutions in the embodiments of the present invention have been clearly and completely described. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0041] To enable those skilled in the art to better understand the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0042] In the description of this invention, it should be understood that the terms "upper", "lower", "top", "bottom", "inner" and "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the position or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations of this invention.

[0043] The efficient self-pressurization technology for converting liquid hydrogen into high-pressure gaseous hydrogen in this invention includes a liquid hydrogen heating and pressurization module and a non-powered filling and replacement module. The liquid hydrogen heating and pressurization module includes a sealed liquid hydrogen storage tank, a heat exchange device, and an external cold energy utilization device connected in sequence. The heat exchange device is located inside the liquid hydrogen storage tank or on both sides of the inner layer. It conducts heat to the internal liquid hydrogen or the inner side of the liquid hydrogen tank through conduction, convection, and thermal radiation. At this time, the liquid hydrogen storage tank is in a sealed state, causing the liquid hydrogen to heat up and pressurize, becoming high-pressure gaseous hydrogen. Alternatively, it can reduce insulation performance through vacuum failure; employ external heating methods such as electric heating, infrared, or microwave heating; or allow the liquid hydrogen storage tank itself to leak heat, causing the internal liquid hydrogen to self-heat and evaporate.

[0044] The non-powered filling and replacement module includes valves, non-powered filling pipes, filling material, and hydrogen utilization device connected in sequence.

[0045] The present invention relates to a highly efficient self-pressurizing system for converting liquid hydrogen into high-pressure gaseous hydrogen. The liquid hydrogen storage tank employs a vacuum-insulated structure design. This structure includes an inner tank for storing liquid hydrogen and an outer tank providing thermal insulation protection. A vacuum is created between the inner and outer layers, and high-vacuum insulation, stacked insulation, or multi-layer vacuum insulation can be used to minimize cold loss during storage. The heat exchange device within the system can employ various methods, depending on the actual application, such as high-efficiency solid-state heat conduction, fluid convection heat transfer, radiative heat transfer, or active external heating, utilizing natural heat leakage from the tank body, or even controlled vacuum failure, to introduce external heat into the tank and increase the temperature and pressure of the liquid hydrogen. An external cold energy utilization device connected to the storage tank is intended for applications requiring cold energy utilization. The specific connection method between the two can be determined according to actual operating conditions to ensure stable and safe system operation. The non-powered filling pipeline used for high-pressure hydrogen replacement connects one end to the outlet of a liquid hydrogen storage tank and the other end to the inlet of a hydrogen utilization device. A valve is installed on the pipeline, which can be matched and connected to the pipeline and opened or closed under set conditions or manual operation. The filling material, serving as the replacement medium, is pre-placed in all or part of the volume of the hydrogen utilization device. Its form can be a spherical, cubic, conical, or irregularly shaped solid substance with dimensions ranging from 0.001 mm to 1000 mm, or it can be a difficult-to-compressible fluid such as water, mercury, or alcohol. During the replacement process, these filling materials enter the liquid hydrogen storage tank under the drive of gravity or magnetic force, thereby replacing an equal volume of high-pressure gaseous hydrogen into the hydrogen utilization device. The liquid hydrogen medium processed by the entire system has a temperature range between 13.96 K and 33.15 K, and a pressure range between 7.04 kPa and 1.29 MPa. The final output high-pressure gaseous hydrogen covers a wide temperature range from 14 K to 500 K and a pressure range from 0.1 MPa to 200 MPa.

[0046] Example 1 As shown in Figure 1, the embodiment discloses a high-efficiency self-pressurization system for converting liquid hydrogen into high-pressure gaseous hydrogen using a high-efficiency heat exchange method, including a high-efficiency heat exchange liquid hydrogen heating and pressurization module and an air liquefaction system module.

[0047] The high-efficiency heat exchange liquid hydrogen heating and pressurization module includes a sealed liquid hydrogen storage tank 1 and a heat exchange device 2. The liquid hydrogen storage tank 1 adopts a vacuum insulation structure design, with an inner tank for storing liquid hydrogen and an outer tank for providing thermal insulation protection. A vacuum is drawn between the inner and outer layers to reduce the loss of cold energy during the liquid hydrogen storage process.

[0048] The heat exchange device 2 is installed in the liquid hydrogen container inside the liquid hydrogen storage tank 1. It contacts the liquid hydrogen in the form of convective heat exchange and conducts the cold energy released by the vaporization of the liquid hydrogen inside to the external cold energy utilization device through the connection between the heat exchange device and the external cold energy utilization device. The convective heat exchange device 2 can be designed as a spiral tube to increase the convective heat exchange area and improve the heat exchange efficiency, thereby more effectively heating and vaporizing the low-temperature liquid hydrogen into high-pressure gaseous hydrogen.

[0049] The air liquefaction system module is an external cold energy utilization device 3, which is connected to the liquid hydrogen storage tank 1 to realize the efficient utilization of the liquid hydrogen cold energy conducted by the heat exchange device and realize the energy recovery and utilization.

[0050] The system operates as follows: First, the cryogenic liquid hydrogen 8 stored in the liquid hydrogen storage tank 1 undergoes convective heat exchange with an externally introduced heat medium through a built-in heat exchange device 2 (such as a spiral tube). After absorbing heat, the liquid hydrogen 8 vaporizes, generating and accumulating high pressure within the sealed liquid hydrogen storage tank 1. Simultaneously, the enormous cold energy generated during vaporization is transported via the pipes of the heat exchange device 2 to an external cold energy utilization device 3 (such as an air liquefaction system) for recovery and utilization. When the pressure inside the tank reaches a set value, preparations are made for subsequent hydrogen output.

[0051] For any component models, material names, connection structures, control methods, algorithms, etc., not explicitly described in this embodiment, they are all considered to be common technical features disclosed in the prior art. Those skilled in the art can implement them based on existing technology or conventional technical means, and they will not be described again in this invention.

[0052] Example 2 As shown in Figure 2, this embodiment discloses an example of a device for replacing high-pressure hydrogen without power. It is an example of a process for high-efficiency liquid hydrogen cold energy recovery by transferring high-pressure gaseous hydrogen through a built-in non-powered device, including a non-powered replacement module and a fuel cell power generation module.

[0053] The non-powered filling and displacement high-pressure hydrogen module includes valve 4, non-powered filling pipeline 5, and filling material 6. Valve 4 is used to control the opening and closing of non-powered filling pipeline 5. It can be a fast-opening and fast-closing solenoid valve with a fast response speed, which can quickly open or close non-powered filling pipeline 5 under certain conditions, ensuring the system's rapid response and precise control.

[0054] The non-powered filling pipe 5 uses a smooth inner surface to reduce resistance loss during hydrogen transportation. When valve 4 is opened, the filler 6 enters the liquid hydrogen storage tank 1 through the non-powered filling pipe 5. Referring to Figures 1 and 2, the filler 6 can be an irregularly shaped solid (such as a steel ball) or a fluid with incompressible properties (such as mercury) as the filler for transferring high-pressure gaseous hydrogen in this non-powered filling replacement unit.

[0055] The fuel cell power generation module is a hydrogen utilization device 7. After receiving hydrogen transferred through the non-powered filling pipeline 5, it is used in the fuel cell power generation equipment to realize the effective utilization of hydrogen.

[0056] This embodiment focuses on the non-powered replacement process of high-pressure hydrogen. When high-pressure hydrogen is formed in the liquid hydrogen storage tank 1 through self-pressurization, valve 4 is opened when it is needed. At this time, under the action of gravity, the solid filler 6 (such as a steel ball) pre-placed in the hydrogen utilization device 7 (such as a fuel cell) flows into the bottom of the liquid hydrogen storage tank 1 through the non-powered filling pipe 5. The filler 6 occupies the space inside the tank, thereby replacing an equal volume of high-pressure hydrogen from the top of the liquid hydrogen storage tank 1. The replaced hydrogen, driven by the pressure difference, flows in the opposite direction through the same pipe 5 into the hydrogen utilization device 7 for its use.

[0057] For any component models, material names, connection structures, control methods, algorithms, etc., not explicitly described in this embodiment, they are all considered to be common technical features disclosed in the prior art. Those skilled in the art can implement them based on existing technology or conventional technical means, and they will not be described again in this invention.

[0058] Example 3 like Figure 3 As shown, this embodiment discloses a highly efficient self-pressurization system that reduces vacuum insulation performance, including a liquid hydrogen heating and pressurization module, a non-powered filling and replacement high-pressure hydrogen module, and an on-board hydrogen refueling system module.

[0059] The liquid hydrogen heating and pressurization module includes a sealed liquid hydrogen storage tank 1 and a heat exchange device 2. When the vacuum structure of the liquid hydrogen storage tank 1 fails, the cold energy of the low-temperature liquid hydrogen inside the tank is released. Due to heat leakage from the tank, the liquid hydrogen is slowly heated to a low-temperature, high-pressure hydrogen of approximately -110°C. At the same time, it is conducted to the external cold energy utilization device 3 through the heat exchange devices 2 on both sides of the inner layer of the liquid hydrogen.

[0060] In this process, valve 4 opens under certain conditions in the non-powered filling and replacement module. An incompressible fluid, 6, is used as the filling material and falls freely into the liquid hydrogen storage tank 1 under gravity, thereby transferring an equal volume of hydrogen gas. This hydrogen gas then flows through the non-powered filling pipeline 5 into the hydrogen utilization device 7. The filling material 6 simultaneously promotes hydrogen flow and mixing within the non-powered filling pipeline 5, improving the efficiency and quality of hydrogen delivery.

[0061] The on-board hydrogen refueling system module is a hydrogen utilization device 7, which receives the hydrogen transferred from the non-powered filling pipeline 5 and uses this portion of hydrogen in the on-board hydrogen refueling system to achieve efficient and clean energy utilization.

[0062] During system operation, the vacuum insulation performance of liquid hydrogen storage tank 1 is controlled to be disrupted (e.g., through a vacuum breaker valve), allowing ambient heat to slowly enter the tank. Liquid hydrogen 8 absorbs this heat and vaporizes, becoming pressurized. The released cold energy can be recovered by the cold energy utilization device 3 outside the heat exchanger 2. Once the pressure reaches the target level, valve 4 is opened, and the incompressible fluid filling material 6 in the hydrogen utilization device 7 (such as an on-board hydrogen refueling system) flows into the liquid hydrogen storage tank 1 through pipe 5 under gravity, thereby replacing an equal volume of high-pressure hydrogen into the utilization device 7.

[0063] For any component models, material names, connection structures, control methods, algorithms, etc., not explicitly described in this embodiment, they are all considered to be common technical features disclosed in the prior art. Those skilled in the art can implement them based on existing technology or conventional technical means, and they will not be described again in this invention.

[0064] Example 4 For magnetic drive, the filler 6 can be made of ferromagnetic material, and permanent magnets or controllable electromagnets can be installed on the outer wall of the non-powered filling pipe 5 or at the inlet of the liquid hydrogen storage tank 1 to guide the directional movement of the filler 6 through the magnetic field gradient. For electric force drive, when the filler 6 is made of lightweight conductive or dielectric material, electrodes can be arranged on both sides of the non-powered filling pipe 5 and voltage can be applied to form an electric field, using the electric field force to make the polarized or charged filler 6 migrate along the field lines. For pressure difference drive, the pressure difference naturally formed between the liquid hydrogen storage tank 1 and the hydrogen utilization device 7 can be directly used to allow the fluid filler 6 (such as water or alcohol) to move through the non-powered filling pipe 5 under the action of the pressure difference. The filling pipe 5 flows into the liquid hydrogen storage tank 1, thereby replacing an equal volume of high-pressure hydrogen. For ejector-driven operation, an ejector structure can be integrated into the non-powered filling pipe 5, with its high-pressure inlet connected to the gas phase space of the liquid hydrogen storage tank 1 and its low-pressure inlet introducing the filling material 6. When the high-pressure hydrogen passes through the ejector, a local negative pressure is generated, carrying the filling material 6 into the liquid hydrogen storage tank 1. For centrifugal force-driven operation, the hydrogen utilization device 7 or its local cavity can be designed as a rotatable structure. Rotation can be driven manually or by utilizing the fluid energy within the system (such as the liquid hydrogen vaporization pressure or the expansion work of the cold energy recovery device), causing the internal filling material 6 to be thrown out and enter the liquid hydrogen storage tank 1 under centrifugal force. All of the above driving methods do not rely on external power or compressors or other active power sources. They only utilize the physical field or natural force existing within the system to achieve the controllable transfer of the filling material 6 and the non-powered replacement of high-pressure hydrogen, ensuring the feasibility of the technical solution of this invention in different application scenarios.

[0065] For any component models, material names, connection structures, control methods, algorithms, etc., not explicitly described in this embodiment, they are all considered to be common technical features disclosed in the prior art. Those skilled in the art can implement them based on existing technology or conventional technical means, and they will not be described again in this invention.

[0066] Example 5 This embodiment, based on Embodiment 2, provides an optional and extended description of the implementation method of the non-powered filling and replacement unit. The hydrogen utilization device 7 is internally divided into a hydrogen chamber and a filling chamber by a flexible diaphragm. The filling material 6 is incompressible hydraulic oil, filling the filling chamber. The inlet of the non-powered filling pipe 5 is connected to the bottom of the filling chamber. During the replacement phase, valve 4 is opened, and the high-pressure gaseous hydrogen in the liquid hydrogen storage tank 1 forces the hydrogen in the hydrogen chamber through another independent pipe into the hydrogen-using device (such as a fuel cell). Simultaneously, under the pressure difference, the hydraulic oil in the filling chamber flows into the bottom of the liquid hydrogen storage tank 1 through the non-powered filling pipe 5, completing the equal-volume replacement of hydrogen. When resetting is required, the system closes the hydrogen output valve and starts a small hydraulic pump connected to the filling chamber to pump the hydraulic oil at the bottom of the liquid hydrogen storage tank 1 back into the filling chamber, preparing for the next replacement. This embodiment clarifies the filling material recovery mechanism, constituting a complete, recyclable system.

[0067] The term "powerless device" as used in this invention refers to the fact that the replacement process of the filler 6 does not rely on complex power equipment such as external compressors or pumps specifically introduced for the core function of compressing hydrogen, but rather does not mean that no energy is required. The driving methods listed in this invention, such as magnetic force, electric field force, ejection effect, and centrifugal force, are intended to demonstrate that the movement of the filler can be achieved through various physical fields, and its energy consumption is far lower than that of traditional hydrogen compressors.

[0068] For any component models, material names, connection structures, control methods, algorithms, etc., not explicitly described in this embodiment, they are all considered to be common technical features disclosed in the prior art. Those skilled in the art can implement them based on existing technology or conventional technical means, and they will not be described again in this invention.

[0069] The above description of the embodiments is provided to enable those skilled in the art to understand and use the invention. It will be apparent to those skilled in the art that various modifications can be made to these embodiments, and the general principles described herein can be applied to other embodiments without inventive effort. Therefore, the present invention is not limited to the above embodiments, and any improvements and modifications made by those skilled in the art based on the disclosure of the present invention without departing from the scope of the invention should be within the protection scope of the present invention.

Claims

1. A highly efficient self-pressurization system for converting liquid hydrogen into high-pressure gaseous hydrogen without a power source, characterized in that, Includes a liquid hydrogen heating and pressurization unit and a non-powered filling and displacement high-pressure hydrogen unit; The liquid hydrogen heating and pressurization unit includes a sealed liquid hydrogen storage tank (1), a heat exchange device (2) installed in the liquid hydrogen storage tank (1), and an external cold energy utilization device (3) connected to the liquid hydrogen storage tank (1). The heat exchange device (2) is used to introduce external heat into the liquid hydrogen storage tank (1) to heat and pressurize the liquid hydrogen therein. The non-powered filling and replacement high-pressure hydrogen unit includes a non-powered filling pipeline (5), a valve (4), a filling material (6), and a hydrogen utilization device (7). The non-powered filling pipe (5) connects the outlet of the liquid hydrogen storage tank (1) to the inlet of the hydrogen utilization device (7), and the valve (4) is provided on the non-powered filling pipe (5) to control its opening and closing. The filling material (6) is placed inside the hydrogen utilization device (7) and can enter the liquid hydrogen storage tank (1) through the valve (4) and the non-powered filling pipe (5) under the drive of any one of gravity, magnetic force, electric field force, pressure difference force, ejection effect, and centrifugal force, so as to replace an equal volume of high-pressure gaseous hydrogen into the hydrogen utilization device (7).

2. The high-efficiency self-pressurization system for converting liquid hydrogen into high-pressure gaseous hydrogen without a power source, as described in claim 1, is characterized in that... The liquid hydrogen storage tank (1) is a double-layer structure container with a vacuum insulation layer.

3. The high-efficiency self-pressurization system for converting liquid hydrogen into high-pressure gaseous hydrogen without a power source, as described in claim 1, is characterized in that... The heat exchange device (2) is a heat exchanger installed inside the liquid hydrogen storage tank (1). The heat exchanger is one of a solid heat conductor, a fluid convection heat exchanger, or a radiation heat exchanger, or one of an external heating heat exchanger, a tank body heat leakage heat exchanger, or a tank insulation vacuum failure heat exchanger. The pipe of the heat exchange device (2) is connected to the external cold energy utilization device (3).

4. The high-efficiency self-pressurization system for converting liquid hydrogen into high-pressure gaseous hydrogen without a power source, as described in claim 1, is characterized in that... The external cold energy utilization device (3) can further process the cold energy transmitted from the liquid hydrogen storage tank (1). The external cold energy utilization device (3) is a low-temperature heat exchanger, cold energy power generation device or low-temperature refrigeration device that is connected to the heat exchange device (2) by a pipeline.

5. The high-efficiency self-pressurization system for converting liquid hydrogen into high-pressure gaseous hydrogen without a power source, as described in claim 1, is characterized in that... The filler (6) is a difficult-to-compress fluid or solid particles.

6. The high-efficiency self-pressurization system for converting liquid hydrogen into high-pressure gaseous hydrogen without a power source, as described in claim 1, is characterized in that... The valve (4) is connected to the non-powered filling pipe (5) by a welded or detachable joint.

7. The high-efficiency self-pressurization system for converting liquid hydrogen into high-pressure gaseous hydrogen without a power source, as described in claim 1, is characterized in that... The non-powered filling pipe (5) is made of hydrogen embrittlement resistant material. One end of the non-powered filling pipe (5) is sealed to the outlet of the liquid hydrogen storage tank (1) through a high-pressure connector, and the other end is sealed to the inlet of the hydrogen utilization device (7) through the valve (4).

8. The high-efficiency self-pressurization system for converting liquid hydrogen into high-pressure gaseous hydrogen without a power source, as described in claim 1, is characterized in that... The heat exchange device (2) includes a vacuum breaking valve disposed in the vacuum insulation jacket of the liquid hydrogen storage tank (1), the vacuum breaking valve being used to controllably break the vacuum insulation state of the liquid hydrogen storage tank (1).

9. The high-efficiency self-pressurization system for converting liquid hydrogen into high-pressure gaseous hydrogen without a power source, as described in claim 1, is characterized in that... The heat exchange device (2) includes an electric heater, an infrared heater or a microwave heater that is attached to the inner and outer walls or the outer side of the inner layer of the liquid hydrogen storage tank (1).

10. The high-efficiency self-pressurization system for converting liquid hydrogen into high-pressure gaseous hydrogen without a power source, as described in claim 1, is characterized in that... The hydrogen utilization device (7) is one of the following: a hydrogen fuel cell power generation device, a hydrogen internal combustion engine, a hydrogen storage and refueling system of a hydrogen refueling station, or an on-board power system capable of utilizing or collecting hydrogen.

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