A high-efficiency heat and mass transfer alloy hydrogen storage tank and its manufacturing method

Abstract

The present invention belongs to the technical field of hydrogen storage devices, and in particular relates to a high-efficiency heat and mass transfer alloy hydrogen storage tank and its manufacturing method. The hydrogen storage tank includes a tank body, a gas valve, a porous stainless steel flow guide tube, a filter element, and a hydrogen storage module. One end of the tank body is fixedly connected to the tank bottom, and the other end is installed with a screw-on buckle cover; the gas valve is located outside the tank body, the filter element is inserted through the center hole at the bottom of the buckle cover along the center axis of the buckle cover, and the porous stainless steel flow guide tube is arranged in the tank body along the center axis of the tube body. The hydrogen storage modules are all filled in the tank body, and each hydrogen storage module includes an alloy and expanded graphite block. The alloy and expanded graphite block are tightly fitted to the adjacent internal heat transfer fins through a heat transfer powder layer. Any two adjacent hydrogen storage modules are tightly fitted, and the porous stainless steel flow guide tube runs through the hydrogen storage module. The manufacturing method of the metal hydride hydrogen storage tank of the present invention is easy to implement, can ensure that the performance of the hydrogen storage material is not affected by the manufacturing method, and can achieve large-scale production.

Description

Technical Field

[0001] The present invention belongs to the technical field of hydrogen storage devices, and in particular relates to a high-efficiency heat and mass transfer alloy hydrogen storage tank and a manufacturing method thereof. Background Art

[0002] In the energy sector, the supply situation is not optimistic. Although the oil market has shifted in supply and demand due to factors such as the entry of US shale oil and gas, the temporary abundance and price decline of oil and gas resources cannot change the long-term energy supply and demand situation. The depletion of non-renewable energy is inevitable. Furthermore, the various harmful emissions generated during the production and use of fossil energy contribute to environmental unsustainability. The current environmental situation no longer allows humanity to consume all fossil energy resources and then transition to more sustainable alternative energy systems.

[0003] Hydrogen is a renewable, clean energy source with a high energy density. As a new energy carrier, it holds broad application prospects. However, hydrogen's low density and ease of release make its storage and transportation extremely challenging. Therefore, developing safe and efficient hydrogen storage technologies is a key factor in realizing hydrogen energy applications. Currently, hydrogen storage methods primarily include high-pressure gaseous storage, cryogenic liquid storage, and solid-state storage using metal hydrides. High-pressure gaseous storage can achieve a high mass hydrogen storage density, but the required pressure results in excessive energy consumption during gas compression. Furthermore, excessive pressure can pose safety issues for devices such as cylinders and valves. Liquid hydrogen storage, on the other hand, requires liquefying the hydrogen at standard atmospheric pressure and cooling it to below -252.7°C. This undoubtedly increases energy consumption and costs, and also complicates safety technologies. Solid-state hydrogen storage, which involves storing hydrogen in a solid material, offers higher volumetric hydrogen storage density, can store low-pressure hydrogen, has low energy consumption, and is highly safe, making it a promising hydrogen storage technology.

[0004] Metal hydride hydrogen storage is a relatively mature solid-state hydrogen storage method currently. However, since the hydrogen absorption and desorption reactions of metal hydride hydrogen storage materials have a large reaction heat effect, the hydrogen storage material is exposed to air for a long time during the filling process and is easily oxidized by high temperatures during the sealing and welding process of the pipe body and the tank body, which can lead to material failure and weakening of hydrogen storage performance. In addition, existing solid-state hydrogen storage tanks are large in size, and the filling operation is somewhat difficult, making them inconvenient to use.

[0005] Therefore, there is an urgent need to design a high-efficiency heat and mass transfer alloy hydrogen storage tank and a manufacturing method thereof to solve the above problems. Summary of the Invention

[0006] In response to the problems existing in the above-mentioned prior art, the purpose of the present invention is to provide a high-efficiency heat and mass transfer alloy hydrogen storage tank and a manufacturing method thereof, so as to improve the heat and mass transfer performance of the hydrogen storage material bed, ensure the rapid absorption / desorption of hydrogen by the alloy hydrogen storage tank, prevent the local aggregation of the hydrogen storage material powder in the hydrogen storage tank, ensure the uniformity of the hydrogen storage material powder, avoid the stress concentration caused by the hydrogen storage material absorbing hydrogen and expanding, which affects the safety performance of the solid-state hydrogen storage tank, and at the same time prevent the oxidation of the hydrogen storage material powder exposed to the air in the tank due to excessive temperature when the tank body is sealed and welded after the internal material is filled, thereby avoiding the failure of the hydrogen storage material powder and the weakening of the hydrogen storage performance.

[0007] The technical solution of the present invention is:

[0008] A high-efficiency heat and mass transfer alloy hydrogen storage tank includes a tank body, a gas valve, a porous stainless steel flow guide tube, a filter element, and a hydrogen storage module. The specific structure is as follows:

[0009] The tank body includes a tube body, one end of which is fixedly connected to the tank bottom, and the other end of the tube body is installed with a screw-on buckle cover, the internal thread of the buckle cover corresponds to the external thread of the other end of the tube body and matches to form a threaded connection between the buckle cover and the tube body, and the corresponding position between the end face of the buckle cover and the side face of the tube body is the welding point between the buckle cover and the tube body;

[0010] The gas valve is located outside the tank body, and an NPT connector is provided at the center of the outer bottom of the buckle cover. The external thread at one end of the gas valve corresponds to the internal thread of the NPT connector and matches to form a threaded connection between the gas valve and the NPT connector. The gas valve and the NPT connector at the outer bottom of the buckle cover are screwed together at the threaded connection between the gas valve and the NPT connector.

[0011] The filter element is installed along the central axis of the buckle cover and is placed in the center hole at the bottom of the buckle cover. One end of the filter element is fixed to the end of the gas valve installed on the NPT connector by welding through the welding point between the gas valve and the filter element. The end of the filter element away from the gas valve is located in the porous stainless steel guide tube.

[0012] The porous stainless steel guide tube is arranged in the tank body along the central axis of the tube body. The external thread at one end of the porous stainless steel guide tube corresponds to the internal thread of the pipe hoop at the center of the bottom inner of the buckle cover and matches to form a threaded connection between the porous stainless steel guide tube and the buckle cover. The porous stainless steel guide tube and the pipe hoop at the bottom inner of the buckle cover are screwed together at the threaded connection between the porous stainless steel guide tube and the buckle cover.

[0013] The hydrogen storage modules are all filled in the tank body, and each hydrogen storage module includes an alloy and expanded graphite block. The alloy and expanded graphite blocks are tightly fitted to the adjacent internal heat transfer fins through a heat transfer powder layer. Any two adjacent hydrogen storage modules are tightly fitted, and a porous stainless steel guide tube runs through the hydrogen storage module; the outer edge of the alloy and expanded graphite block is gap-matched with the tube body, leaving space for the hydrogen storage alloy to absorb hydrogen and expand.

[0014] During the manufacturing process of the high-efficiency heat and mass transfer alloy hydrogen storage tank, the tube body is first screwed to the buckle cover at the threaded connection between the buckle cover and the tube body. After the tank body is filled with argon to protect the hydrogen storage material, the buckle cover and the tube body are fixedly connected at the welding point between the buckle cover and the tube body by welding.

[0015] The high-efficiency heat and mass transfer alloy hydrogen storage tank also includes a pressure gauge, a safety pressure relief valve, and a temperature sensor. The pressure gauge and safety pressure relief valve are installed on the outside of the tank bottom. The temperature sensor is penetrated through the tank bottom in a direction parallel to the central axis of the tube body and is sealed to the tank bottom by a ferrule; one end of the temperature sensor is inserted between the alloy and the expanded graphite block, and the temperature sensor passes through part of the hydrogen storage module.

[0016] The high-efficiency heat and mass transfer alloy hydrogen storage tank also includes external heat exchange fins and internal heat transfer fins. The external heat exchange fins are fixedly connected to the outer side of the tube body and are evenly arranged along the axial direction of the tube body; the internal heat transfer fins are fixedly connected to the inner side of the tube body and are evenly arranged along the axial direction of the tube body. Each internal heat transfer fin is coated with a heat transfer powder layer on both sides.

[0017] The high-efficiency heat and mass transfer alloy hydrogen storage tank has an internal heat transfer fin whose diameter is adapted to the inner diameter of the tube body, and a gap between the internal heat transfer fin and the tube body is matched, and a thermal conductive adhesive is coated at the gap between the internal heat transfer fin and the tube body; the inner diameter of the external heat exchange fin is adapted to the outer diameter of the tube body; the internal heat transfer fin and the external heat exchange fin are copper sheets, and the thickness of the internal heat transfer fin and the external heat exchange fin is 0.2mm to 1mm; a through hole is provided at the center of the internal heat dissipation fin for the porous stainless steel guide tube to pass through, and some internal heat dissipation fins have an additional through hole for the temperature sensor to pass through.

[0018] The high-efficiency heat and mass transfer alloy hydrogen storage tank has a hydrogen storage module comprising internal heat transfer fins, a heat transfer powder layer, and an alloy and expanded graphite compact. The heat transfer powder layer is located between the alloy and expanded graphite compact and the internal heat transfer fins, and has a thickness of 0.1 mm to 0.5 mm. The internal heat transfer fins and the alloy and expanded graphite compact are each provided with a central through hole, and a porous stainless steel flow guide pipe penetrates the internal heat transfer fins, the alloy and expanded graphite compact. The hydrogen storage module is composed of a heat transfer powder layer-expanded graphite compact-heat transfer powder layer-internal heat transfer fins, and is filled in the tank body. The heat transfer powder layer reduces the pores between the internal heat transfer fins and the alloy and expanded graphite compact. A temperature sensor is inserted into the alloy and expanded graphite compact to monitor the temperature in real time.

[0019] In the high-efficiency heat and mass transfer alloy hydrogen storage tank, the alloy and expanded graphite compact is formed by pressing hydrogen storage material powder and expanded graphite worms. The mass ratio of the hydrogen storage material powder to the expanded graphite worms is 7 / 3 to 99 / 1, the compaction pressure is 10 MPa to 300 MPa, and the thickness of the alloy and expanded graphite compact is 10 mm to 60 mm. The hydrogen storage material powder in the alloy and expanded graphite compact is a rare earth AB5 type hydrogen storage alloy, a titanium AB2 type hydrogen storage alloy, or a Mg-based hydrogen storage alloy, and the particle size of the hydrogen storage material powder ranges from 0.1 mm to 1 mm.

[0020] The high-efficiency heat and mass transfer alloy hydrogen storage tank has a buckle cover, a tube body and a tank bottom made of aluminum alloy or stainless steel. The outer diameter of the tube body is 20mm to 100mm, and the wall thickness of the tube body is 3mm to 10mm. The filter element is a metal tubular structure processed by powder metallurgy. The diameter of the filter element is 6mm to 8mm, the length of the filter element is 30mm to 60mm, the pore size of the filter element is 1μm to 5μm, and the porosity is 25% to 30%.

[0021] The method for manufacturing the high-efficiency heat and mass transfer alloy hydrogen storage tank comprises the following steps:

[0022] (1) mixing hydrogen storage material powder and expanded graphite worms in corresponding proportions;

[0023] (2) After mixing, the mixture is placed in a mold for briquetting, and the alloy and expanded graphite briquette are pressed into briquettes of the same thickness;

[0024] (3) After the briquetting is completed, holes are drilled in the alloy and expanded graphite briquette and the internal heat transfer fins, with the holes being divided into two types: one through the porous stainless steel guide tube and the temperature sensor, and the other through the porous stainless steel guide tube only;

[0025] (4) Weld the gas valve and the filter element at the welding point between the gas valve and the filter element;

[0026] (5) Weld the tank bottom to the ground, polished and cleaned tube body;

[0027] (6) After welding is completed, install the pressure gauge and safety relief valve on the bottom of the tank, insert the temperature sensor into the bottom of the tank, and seal it with a ferrule;

[0028] (7) Fill the bottom of the tank with a layer of heat transfer powder, place the pressed alloy and expanded graphite blocks into the tank, then lay a layer of heat transfer powder, apply thermal conductive glue on the edge of the internal heat transfer fins, and then place the internal heat transfer fins into the tank to complete the filling of one hydrogen storage module. Repeat the above filling process until all hydrogen storage modules are filled;

[0029] (8) After filling is completed, the porous stainless steel guide tube and the buckle cover are screwed together at the threaded connection between the porous stainless steel guide tube and the buckle cover;

[0030] (9) Place a rubber ring on the top of the tube body, then insert the combination of the buckle cover and the porous stainless steel guide tube into the tank, and screw the buckle cover to the tube body at the threaded connection between the buckle cover and the tube body;

[0031] (10) After the threaded connection is completed, the gas valve and filter element assembly is threadedly connected to the NPT connector at the threaded connection between the gas valve and the NPT connector;

[0032] (11) Evacuate the tank through the gas valve, then fill it with argon gas and repeat the purge 2 to 4 times;

[0033] (12) After the gas washing is completed, close the gas valve and weld the buckle cover and the tube body at the welding point between the buckle cover and the tube body;

[0034] (13) The external heat exchange fins are then welded to the tube body to complete the production of the hydrogen storage tank.

[0035] In the manufacturing method of the high-efficiency heat and mass transfer alloy hydrogen storage tank, in step (7), heat transfer powder is filled into the bottom position of the tank body, one end of the heat transfer powder is in close contact with the tank bottom, and the other end of the heat transfer powder is in close contact with the nearest alloy and expanded graphite block.

[0036] The advantages and beneficial effects of the present invention are:

[0037] 1. The present invention reduces the gaps between the internal heat transfer fins and the alloy and expanded graphite blocks through a heat transfer powder layer, and applies thermal conductive adhesive at the gaps between the internal heat transfer fins and the tube body to increase the fit between the internal heat transfer fins and the tube body. At the same time, heat exchange fins are fixed to the outside of the tank body, greatly improving the heat transfer efficiency inside the metal hydride hydrogen storage tank and ensuring that the alloy hydrogen storage tank can quickly absorb / release hydrogen.

[0038] 2. The present invention divides the hydrogen storage alloy powder filled in the tank into hydrogen storage modules through the partition of internal heat transfer fins, thereby preventing the local aggregation of the hydrogen storage material powder in the hydrogen storage tank, ensuring the uniformity of the hydrogen storage material powder, and avoiding the stress concentration caused by the hydrogen absorption and expansion of the hydrogen storage material to affect the safety performance of the solid-state hydrogen storage tank.

[0039] 3. The present invention achieves a sealing effect by pre-threading the buckle cover and the tube body, then installing the valve, vacuuming and filling with argon gas to isolate the hydrogen storage material powder in the tank from the air, and finally using welding to fix the buckle cover and the tube body, thereby preventing the hydrogen storage material powder exposed to the air from being oxidized due to excessive temperature, avoiding the failure of the hydrogen storage material powder and the weakening of the hydrogen storage performance.

[0040] 4. The present invention is equipped with a pressure gauge, a safety pressure relief valve and a temperature sensor, which facilitates real-time monitoring of relevant parameters in the alloy hydrogen storage tank and improves the service life and safety of the alloy hydrogen storage tank.

[0041] 5. The present invention can achieve the purpose of rapid input and output of hydrogen by arranging a short filter element in combination with a porous stainless steel guide tube. At the same time, it can prevent the hydrogen storage material powder from flowing out with the air flow when releasing hydrogen, resulting in a decrease in the hydrogen storage capacity of the hydrogen storage tank, thereby reducing costs compared to using a through-type filter element.

[0042] 6. The manufacturing method of the metal hydride hydrogen storage tank of the present invention is easy to implement, can ensure that the performance of the hydrogen storage material is not affected by the manufacturing method, and can achieve large-scale production. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0044] Figure 1 This is a schematic diagram of the main structure of a high-efficiency heat and mass transfer alloy hydrogen storage tank of the present invention;

[0045] Figure 2 This is a schematic cross-sectional view of a high-efficiency heat and mass transfer alloy hydrogen storage tank according to the present invention;

[0046] Figure 3 for Figure 2 A magnified view of middle A;

[0047] Figure 4 Schematic diagram of the structure of the alloy and expanded graphite mixture compact in the present invention. (a) is used for a porous stainless steel guide tube, and (b) is used for a porous stainless steel guide tube and a temperature sensor.

[0048] Figure 5 Schematic diagram of the structure of the internal heat transfer fins in the present invention. (a) is used for the porous stainless steel guide tube, and (b) is used for the porous stainless steel guide tube and temperature sensor.

[0049] Figure 6 Schematic diagram of the structure of the external heat exchange fins in the present invention;

[0050] Among them, 1. Gas valve; 2. Threaded connection between gas valve and NPT connector; 3. NPT connector; 4. Filter element; 5. Buckle cover; 6. Threaded connection between buckle cover and pipe body; 7. Welding point between buckle cover and pipe body; 8. Pipe body; 9. External heat exchange fins; 10. Alloy and expanded graphite blocks; 11. Heat transfer powder layer; 12. Internal heat transfer fins; 13. Thermal adhesive; 14. Porous stainless steel guide tube; 15. Tank bottom; 16. Pressure gauge; 17. Welding point between gas valve and filter element; 18. Threaded connection between porous stainless steel guide tube and buckle cover; 19. Rubber ring; 20. Temperature sensor; 21. Heat transfer powder; 22. Safety pressure relief valve; 23. Pipe clamp. DETAILED DESCRIPTION

[0051] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0052] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0053] like Figures 1 to 6 As shown, the present invention provides a high-efficiency heat and mass transfer alloy hydrogen storage tank, including a tank body, a gas valve 1, a porous stainless steel flow guide tube 14, a filter element 4, a plurality of hydrogen storage modules, an external heat exchange fin 9, a pressure gauge 16, a safety pressure relief valve 22, and a temperature sensor 20. The specific structure is as follows:

[0054] The tank body comprises a tube 8, one end of which is fixedly connected to a tank bottom 15. A screw-on cap 5 is mounted on the other end of the tube 8. The internal threads of the cap 5 correspond to the external threads on the other end of the tube 8, forming a threaded connection 6 between the cap and the tube. The end face of the cap 5 corresponds to the side face of the tube 8, forming a weld 7 between the cap and the tube. During the manufacturing process, the tube 8 is first screwed to the cap 5 at the threaded connection 6. After the tank is filled with argon gas to protect the hydrogen storage material, the cap 5 and the tube 8 are fixedly connected at the weld 7.

[0055] The gas valve 1 is located outside the tank body, and an NPT connector 3 is provided at the center of the outer bottom of the buckle cover 5. The external thread at one end of the gas valve 1 corresponds to the internal thread of the NPT connector 3 and matches to form a gas valve and NPT connector threaded connection 2. The gas valve 1 and the NPT connector 3 at the outer bottom of the buckle cover 5 are threadedly connected at the gas valve and NPT connector threaded connection 2;

[0056] The filter element 4 is inserted into the center hole at the bottom of the buckle cover 5 along the central axis of the buckle cover 5. One end of the filter element 4 is fixedly connected to the end of the gas valve 1 installed on the NPT connector 3 by welding at the gas valve and filter element welding point 17. The end of the filter element 4 away from the gas valve 1 is located in the porous stainless steel guide tube 14.

[0057] The porous stainless steel guide tube 14 is disposed within the tank body along the central axis of the tube body 8. The external thread at one end of the porous stainless steel guide tube 14 corresponds to the internal thread of the pipe hoop 23 at the center of the inner bottom of the buckle cover 5 and matches to form a threaded connection 18 between the porous stainless steel guide tube and the buckle cover. The porous stainless steel guide tube 14 and the pipe hoop 23 at the inner bottom of the buckle cover 5 are screwed together at the threaded connection 18 between the porous stainless steel guide tube and the buckle cover.

[0058] The pressure gauge 16 and the safety relief valve 22 are installed on the outside of the tank bottom 15. The temperature sensor 20 is passed through the tank bottom 15 in a direction parallel to the central axis of the tube 8 and is sealed with the tank bottom 15 by a ferrule.

[0059] The external heat exchange fins 9 are fixed to the outside of the tube body 8 and are evenly arranged along the axial direction of the tube body 8; the internal heat transfer fins 12 are fixed to the inside of the tube body 8 and are evenly arranged along the axial direction of the tube body 8. Each internal heat transfer fin 12 is coated with a heat transfer powder layer 11 on both sides;

[0060] The hydrogen storage modules are all filled in the tank body, and each hydrogen storage module includes an alloy and expanded graphite block 10. The alloy and expanded graphite block 10 and the adjacent internal heat transfer fins 12 are tightly fitted through the heat transfer powder layer 11. Any two adjacent hydrogen storage modules are tightly fitted and have a gap with the tube body 8. The porous stainless steel guide tube 14 runs through the hydrogen storage module. One end of the temperature sensor 20 is inserted between the alloy and expanded graphite block 10, and the temperature sensor 20 passes through part of the hydrogen storage module. The outer edge of the alloy and expanded graphite block 10 is gap-fitted with the tube body 8, leaving room for the hydrogen storage alloy to absorb hydrogen and expand. The metal hydride hydrogen storage tank structure of the present invention is easy to implement a filling method that ensures complete hydrogen storage performance and can be produced on a large scale.

[0061] Furthermore, the total height of the tank body is 100 mm to 1600 mm.

[0062] Furthermore, the hydrogen storage module includes internal heat transfer fins 12, a heat transfer powder layer 11, and an alloy and expanded graphite compact 10. The heat transfer powder layer 11 is located between the alloy and expanded graphite compact 10 and the internal heat transfer fins 12. The internal heat transfer fins 12 and the alloy and expanded graphite compact 10 are each provided with a central through hole, and a porous stainless steel guide tube 14 passes through the internal heat transfer fins 12 and the alloy and expanded graphite compact 10. A temperature sensor 20 is inserted into the alloy and expanded graphite compact 10 to monitor the temperature in real time.

[0063] Furthermore, the diameter of the internal heat transfer fins 12 is adapted to the inner diameter of the tube body 8, so that the internal heat transfer fins 12 can be better placed in the tank body, and at the same time, a thermal conductive adhesive 13 is applied to the gap between the internal heat transfer fins 12 and the tube body 8; Figure 6 As shown, the inner diameter of the external heat exchange fin 9 is adapted to the outer diameter of the tube body 8, so that the external heat exchange fin 9 can be better fixed to the tube body 8; the present invention adopts a hydrogen storage module composed of a heat transfer powder layer 11-expanded graphite block 10-heat transfer powder layer 11-internal heat transfer fin 12, and fills this hydrogen storage module into the tank body. The heat transfer powder layer 11 reduces the pores between the internal heat transfer fin 12 and the alloy and the expanded graphite block 10, thereby greatly improving the heat transfer efficiency inside the metal hydride hydrogen storage tank, and under the action of the external heat exchange fin 9, ensuring the rapid absorption / desorption of hydrogen by the alloy hydrogen storage tank; and the partition of the internal heat transfer fin prevents the local aggregation of the hydrogen storage material in the hydrogen storage tank, ensures the uniformity of the hydrogen storage material, and avoids the stress concentration caused by the hydrogen absorption and expansion of the hydrogen storage material from affecting the safety performance of the solid-state hydrogen storage tank.

[0064] Furthermore, the internal heat transfer fins 12 and the external heat exchange fins 9 are made of copper sheets, and the thickness of the internal heat transfer fins 12 and the external heat exchange fins 9 is 0.2 mm to 1 mm. A through hole is provided at the center of the internal heat dissipation fins 12 for the porous stainless steel guide tube 14 to pass through. Some internal heat dissipation fins 12 also need to have an additional through hole for the temperature sensor 20 to pass through.

[0065] Furthermore, the alloy and expanded graphite compact 10 is formed by pressing hydrogen storage material powder and expanded graphite worms, the compaction pressure is 10MPa~300MPa, and the thickness of the alloy and expanded graphite compact 10 is 10mm~60mm; the expanded graphite worms can not only improve the thermal management efficiency, but also improve the safety of the hydrogen storage tank, and thus the alloy and expanded graphite compact 10 helps to improve the heat transfer effect of the alloy hydrogen storage tank.

[0066] Furthermore, the hydrogen storage material powder in the alloy and expanded graphite compact 10 is a rare earth AB5 type hydrogen storage alloy, a titanium AB2 type hydrogen storage alloy or a Mg-based hydrogen storage alloy, and the particle size of the hydrogen storage material powder ranges from 0.1 mm to 1 mm.

[0067] Furthermore, the mass ratio of the hydrogen storage material powder to the expanded graphite worms in the alloy and expanded graphite compact 10 is 7 / 3 to 99 / 1.

[0068] Furthermore, the buckle cover 5, the tube body 8 and the tank bottom 15 are made of aluminum alloy or stainless steel. The outer diameter of the tube body 8 is 20 mm to 100 mm, and the wall thickness of the tube body 8 is 3 mm to 10 mm.

[0069] Furthermore, the filter element 4 is a metal tubular structure manufactured using powder metallurgy. Its diameter ranges from 6mm to 8mm, its length from 30mm to 60mm, its pore size from 1μm to 5μm, and its porosity from 25% to 30%. The metal filter element 4 facilitates rapid hydrogen input and output. Furthermore, its pore size and porosity ensure effective filtration of the hydrogen storage material powder, preventing it from escaping with the airflow during hydrogen release, which could reduce the hydrogen storage capacity of the hydrogen storage tank.

[0070] Furthermore, the heat transfer powder 21 is filled into the tank bottom 15 in the tank body, with one end of the heat transfer powder 21 in close contact with the tank bottom 15 and the other end of the heat transfer powder 21 in close contact with the nearest alloy and expanded graphite compact 10 .

[0071] Furthermore, the length of the threaded connection 6 between the buckle cover and the tube body is 20mm to 200mm, which is mainly used for the threaded connection between the buckle cover 5 and the tube body 8. The buckle cover 5 and the tube body 8 need to have an interference fit to ensure sealing, and a rubber ring 19 is placed on the contact surface between one end of the tube body 8 and the inner bottom of the buckle cover 5 for sealing.

[0072] Furthermore, a boss is set on the NPT connector 3 of the buckle cover 5 to facilitate wrench clamping and convenient installation and removal of the gas valve 1.

[0073] Furthermore, the present invention provides a method for manufacturing a high-efficiency heat and mass transfer alloy hydrogen storage tank:

[0074] (1) mixing hydrogen storage material powder and expanded graphite worms in corresponding proportions;

[0075] (2) After mixing, the mixture is placed in a mold for briquetting to form alloy and expanded graphite briquette 10 of the same thickness;

[0076] (3) Figure 4-Figure 5 As shown, after the pressing is completed, the alloy and expanded graphite pressed block 10 and the internal heat transfer fin 12 are drilled, which are divided into two types of holes: one through the porous stainless steel guide tube 14 and the temperature sensor 20, and the other through the porous stainless steel guide tube 14 only;

[0077] (4) Welding the gas valve 1 and the filter element 4 at the gas valve and filter element welding point 17;

[0078] (5) Welding the tank bottom 15 to the tube body 8 after grinding, polishing and cleaning;

[0079] (6) After welding is completed, install the pressure gauge 16 and the safety relief valve 22 on the tank bottom 15, insert the temperature sensor 20 into the tank bottom 15, and seal it with a ferrule;

[0080] (7) Fill a small amount of heat transfer powder 21 at the bottom of the tank (the heat transfer powder can be aluminum nitride, graphene, carbon powder, iron powder or aluminum powder, etc., with a thickness of 0.1mm to 0.5mm), place the pressed alloy and expanded graphite block 10 into the tank, and then lay a layer of heat transfer powder 11, apply thermal conductive glue 13 on the edge of the internal heat transfer fin 12, and then place the internal heat transfer fin 12 into the tank to complete the filling of one hydrogen storage module. Repeat the above filling process until all hydrogen storage modules are filled;

[0081] (8) After filling is completed, the porous stainless steel guide tube 14 and the buckle cover 5 are screwed together at the threaded connection 18 between the porous stainless steel guide tube and the buckle cover;

[0082] (9) Place a rubber ring 19 on the top of the tube body 8, then insert the combination of the buckle cover 5 and the porous stainless steel guide tube 14 into the tank, and screw the buckle cover 5 and the tube body 8 together at the screw connection 6 between the buckle cover and the tube body;

[0083] (10) After the threaded connection is completed, the gas valve 1 and the filter element 4 are threadedly connected to the NPT connector 3 at the threaded connection point 2 between the gas valve and the NPT connector;

[0084] (11) Evacuate the tank through gas valve 1, then fill it with argon gas and repeat the purge three times;

[0085] (12) After the gas washing is completed, close the gas valve 1 and weld the buckle cover 5 and the tube body 8 at the welding point 7 between the buckle cover and the tube body;

[0086] (13) Then, the external heat exchange fins 9 are welded to the tube body 8 to complete the production of the hydrogen storage tank.

[0087] Below, the present invention is further described in detail by examples.

[0088] Example 1:

[0089] In this embodiment, the total length of the tank body is 150 mm, the material of the tube body 8 is 316L stainless steel, the outer diameter of the tube body 8 is 80 mm, the wall thickness of the tube body 8 is 5 mm, the length of the tube body 8 is 130 mm, the thickness of the tank bottom 15 is 10 mm, and the thickness of the buckle cover 5 is 10 mm;

[0090] The filter element 4 is made of sintered metal powder (stainless steel powder in this embodiment). The pore size of the filter element 4 is 1 to 5 μm, the porosity is 25%, the outer diameter of the filter element 4 is 8 mm, the wall thickness of the filter element 4 is 1.2 mm, and the length of the filter element 4 is 30 mm.

[0091] The internal heat transfer fins 12 are made of copper, with an outer diameter of 70 mm and a thickness of 0.5 mm. The external heat exchange fins 9 are made of copper, with an inner diameter of 80 mm and an outer diameter of 120 mm.

[0092] The porous stainless steel flow guide tube 14 has a length of 120 mm, an inner diameter of 9 mm, and an outer diameter of 11 mm. Through holes are provided on the tube wall, with a porosity of 25% and an average pore diameter of 1 to 5 μm.

[0093] The hydrogen storage material powder is a rare earth AB5 type LaNi5-based hydrogen storage alloy powder. The main components, by mass percentage, are: La (21.01%), Ce (10.60%), Ni (59.93%), Co (6.75%), and Mn (1.71%). The alloy can be fully activated after 3 to 4 cycles of hydrogen absorption and desorption, and the mass hydrogen storage density reaches 1.2 wt.%. The particle size of the hydrogen storage material powder ranges from 0.1 mm to 1 mm, and the total filling mass of the hydrogen storage material powder is 1.8 kg.

[0094] The expanded graphite is expanded graphite worms obtained by expanding 80-mesh expandable graphite, and the total filling mass of the expanded graphite is 0.0947 kg;

[0095] The alloy and expanded graphite compact 10 is formed by pressing 1.8 kg of LaNi5-based alloy and 0.0947 kg of expanded graphite at 20 MPa, wherein the hydrogen storage material powder accounts for 95% by mass in the alloy and expanded graphite compact 10;

[0096] The alloy hydrogen storage tank of this embodiment was used to conduct hydrogen absorption and desorption performance tests. In the hydrogen absorption test, the hydrogen storage tank was able to charge a vacuum metal hydride hydrogen storage tank to 90% of its maximum hydrogen absorption capacity within 30 minutes. The saturated metal hydride hydrogen storage tank could stably release hydrogen for 240 minutes at a desorption rate of 1 L / min, indicating that the hydrogen storage tank has good heat and mass transfer performance, and the internal hydrogen storage alloy did not fail due to the high welding temperature, thereby ensuring the hydrogen absorption and desorption performance of the alloy hydrogen storage tank.

[0097] Example 2:

[0098] In this embodiment, the total length of the tank body is 970 mm, the material of the tube body 8 is 6061 aluminum alloy, the outer diameter of the tube body 8 is 85 mm, the wall thickness of the tube body 8 is 5 mm, the length of the tube body 8 is 950 mm, the thickness of the tank bottom 15 is 10 mm, and the thickness of the buckle cover 5 is 10 mm;

[0099] The filter element 4 is made of sintered metal powder (stainless steel powder in this embodiment). The pore size of the filter element 4 is 1 to 5 μm, the porosity is 30%, the outer diameter of the filter element 4 is 8 mm, the wall thickness of the filter element 4 is 1.2 mm, and the length of the filter element 4 is 50 mm.

[0100] The internal heat transfer fins 12 are made of copper, with an outer diameter of 75 mm and a thickness of 0.3 mm. The external heat exchange fins 9 are made of copper, with an inner diameter of 85 mm and an outer diameter of 130 mm.

[0101] The porous stainless steel flow guide tube 14 has a length of 940 mm, an inner diameter of 9 mm, and an outer diameter of 11 mm. Through holes are provided on the tube wall, with a porosity of 30% and an average pore diameter of 1 to 5 μm.

[0102] The hydrogen storage material powder is a Ti-V-Cr alloy composed primarily of 30.39% Ti, 44.35% Cr, and 25.26% V by mass. After initial vacuuming, the alloy absorbs hydrogen, achieving a mass hydrogen storage density of 1.7 wt%. The particle size of the hydrogen storage material powder ranges from 0.1 mm to 1 mm, and the total filling mass of the hydrogen storage material powder is 16.5 kg.

[0103] The expanded graphite is expanded graphite worms obtained by expanding 80-mesh expandable graphite, and the total filling mass of the expanded graphite is 0.51 kg;

[0104] The alloy and expanded graphite compact 10 is formed by pressing 16.5 kg of Ti-V-Cr alloy and 0.51 kg of expanded graphite at 20 MPa, wherein the hydrogen storage material powder accounts for 97% by mass of the alloy and expanded graphite compact 10;

[0105] The alloy hydrogen storage tank of this embodiment was used to conduct hydrogen absorption and desorption performance tests. In the hydrogen absorption test, the hydrogen storage tank was able to charge a vacuum metal hydride hydrogen storage tank to 90% of its maximum hydrogen absorption capacity within 200 minutes. The saturated metal hydride hydrogen storage tank could stably release hydrogen for 2950 minutes at a desorption rate of 1 L / min, indicating that the hydrogen storage tank has good heat and mass transfer performance, and the internal hydrogen storage alloy did not fail due to the high welding temperature, thereby ensuring the hydrogen absorption and desorption performance of the alloy hydrogen storage tank.

[0106] Example 3:

[0107] In this embodiment, the total length of the tank body is 416 mm, the material of the tube body 8 is 316L stainless steel, the outer diameter of the tube body 8 is 50 mm, the wall thickness of the tube body 8 is 4 mm, the length of the tube body 8 is 400 mm, the thickness of the tank bottom 15 is 8 mm, and the thickness of the buckle cover 5 is 8 mm;

[0108] The filter element 4 is made of sintered metal powder (iron powder in this embodiment). The pore size of the filter element 4 is 1 to 5 μm, the porosity is 25%, the outer diameter of the filter element 4 is 6 mm, the wall thickness of the filter element 4 is 1.2 mm, and the length of the filter element 4 is 40 mm.

[0109] The internal heat transfer fins 12 are made of copper, with an outer diameter of 42 mm and a thickness of 0.5 mm. The external heat exchange fins 9 are made of copper, with an inner diameter of 50 mm and an outer diameter of 80 mm.

[0110] The porous stainless steel flow guide tube 14 has a length of 390 mm, an inner diameter of 7 mm, and an outer diameter of 9 mm. Through holes are provided on the tube wall, with a porosity of 25% and an average pore diameter of 1 to 5 μm.

[0111] The hydrogen storage material powder is Ti 0.93 Zr 0.07 Mn 1.1 Cr 0.72 V 0.18 The alloy can be fully activated after 1-2 cycles of hydrogen absorption and desorption, with a mass hydrogen storage density of 1.8wt.%. The particle size of the hydrogen storage material powder ranges from 0.1mm to 1mm, and the total filling mass of the hydrogen storage material powder is 2.13kg.

[0112] The expanded graphite is expanded graphite worms obtained by expanding 80-mesh expandable graphite, and the total filling mass of the expanded graphite is 0.1121 kg;

[0113] Alloy and expanded graphite briquette 10 is 2.13kg Ti 0.93 Zr 0.07 Mn 1.1 Cr 0.72 V 0.18 The alloy is pressed with 0.1121 kg of expanded graphite at 30 MPa, and the mass of the hydrogen storage material powder in the alloy and expanded graphite compact 10 accounts for 95%;

[0114] The alloy hydrogen storage tank of this embodiment was used to conduct hydrogen absorption and desorption performance tests. In the hydrogen absorption test, the hydrogen storage tank was able to charge a vacuum metal hydride hydrogen storage tank to 90% of its maximum hydrogen absorption capacity within 30 minutes. The saturated metal hydride hydrogen storage tank could stably release hydrogen for 430 minutes at a desorption rate of 1 L / min, indicating that the hydrogen storage tank has good heat and mass transfer performance, and the internal hydrogen storage alloy did not fail due to the high welding temperature, thereby ensuring the hydrogen absorption and desorption performance of the alloy hydrogen storage tank.

[0115] The implementation results show that the alloy hydrogen storage tank of the present invention improves the heat and mass transfer performance of the hydrogen storage material bed, ensures that the solid-state hydrogen storage tank quickly absorbs / releases hydrogen, prevents the local aggregation of hydrogen storage material powder in the hydrogen storage tank, ensures the uniformity of the hydrogen storage material powder, avoids the stress concentration caused by the hydrogen storage material absorbing hydrogen and expanding, which affects the safety performance of the solid-state hydrogen storage tank, and prevents the oxidation of the hydrogen storage material powder exposed to the air in the tank due to excessive temperature when the tank body is sealed and welded after the internal material is filled, thereby avoiding the failure of the hydrogen storage material powder and the weakening of the hydrogen storage performance. At the same time, the temperature and pressure in the tank can be monitored in real time.

[0116] In the description of the present invention, it should be understood that the terms "longitudinal", "transverse", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the present invention, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation. Therefore, they should not be understood as limiting the present invention.

[0117] The embodiments described above are merely descriptions of preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Without departing from the spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by persons skilled in the art should fall within the scope of protection defined by the claims of the present invention.

Claims

1. A high-efficiency heat and mass transfer alloy hydrogen storage tank, characterized in that: It includes a tank body, a gas valve, a porous stainless steel flow guide pipe, a filter element, and a hydrogen storage module. The specific structure is as follows: The tank body includes a tube body, one end of which is fixedly connected to the tank bottom, and the other end of the tube body is installed with a screw-on buckle cover, the internal thread of the buckle cover corresponds to the external thread of the other end of the tube body and matches to form a threaded connection between the buckle cover and the tube body, and the corresponding position between the end face of the buckle cover and the side face of the tube body is the welding point between the buckle cover and the tube body; The gas valve is located outside the tank body, and an NPT connector is provided at the center of the outer bottom of the buckle cover. The external thread at one end of the gas valve corresponds to the internal thread of the NPT connector and matches to form a threaded connection between the gas valve and the NPT connector. The gas valve and the NPT connector at the outer bottom of the buckle cover are screwed together at the threaded connection between the gas valve and the NPT connector. The filter element is installed along the central axis of the buckle cover and is placed in the center hole at the bottom of the buckle cover. One end of the filter element is fixed to the end of the gas valve installed on the NPT connector by welding through the welding point between the gas valve and the filter element. The end of the filter element away from the gas valve is located in the porous stainless steel guide tube. The porous stainless steel guide tube is arranged in the tank body along the central axis of the tube body. The external thread at one end of the porous stainless steel guide tube corresponds to the internal thread of the pipe hoop at the center of the bottom inner of the buckle cover and matches to form a threaded connection between the porous stainless steel guide tube and the buckle cover. The porous stainless steel guide tube and the pipe hoop at the bottom inner of the buckle cover are screwed together at the threaded connection between the porous stainless steel guide tube and the buckle cover. The hydrogen storage modules are all filled in the tank body, and each hydrogen storage module includes an alloy and expanded graphite block. The alloy and expanded graphite blocks are tightly bonded to adjacent internal heat transfer fins through a heat transfer powder layer. Any two adjacent hydrogen storage modules are tightly bonded. A porous stainless steel guide tube runs through the hydrogen storage module. The outer edge of the alloy and expanded graphite block is gap-fitted with the tube body, leaving space for the hydrogen storage alloy to absorb hydrogen and expand. During the manufacturing process, the tube body is first screwed to the buckle cover at the threaded connection between the buckle cover and the tube body. After the tank body is filled with argon to protect the hydrogen storage material, the buckle cover and the tube body are fixed at the welding point between the buckle cover and the tube body by welding. It also includes external heat exchange fins and internal heat transfer fins. The external heat exchange fins are fixedly connected to the outside of the tube body and are evenly arranged along the axial direction of the tube body. The internal heat transfer fins are fixedly connected to the inside of the tube body and are evenly arranged along the axial direction of the tube body. Each internal heat transfer fin is coated with a heat transfer powder layer on both sides. The diameter of the internal heat transfer fins matches the inner diameter of the tube body, and the gap between the internal heat transfer fins and the tube body is matched. At the same time, thermal conductive glue is applied in the gap between the internal heat transfer fins and the tube body. The inner diameter of the external heat transfer fins matches the outer diameter of the tube body. The internal and external heat transfer fins are copper sheets with a thickness of 0.2mm to 1mm. A through hole is opened at the center of the internal heat transfer fin for the porous stainless steel guide tube to pass through. Some internal heat transfer fins have an additional through hole for the temperature sensor to pass through. The hydrogen storage module includes internal heat transfer fins, a heat transfer powder layer, and alloy and expanded graphite briquettes. The heat transfer powder layer is located between the alloy and expanded graphite briquettes and the internal heat transfer fins, and the thickness of the heat transfer powder layer is 0.1mm~0.5mm. The internal heat transfer fins, alloy and expanded graphite briquettes are all provided with central through holes, and porous stainless steel guide tubes run through the internal heat transfer fins, alloy and expanded graphite briquettes. The hydrogen storage module is composed of a heat transfer powder layer-expanded graphite briquettes-heat transfer powder layer-internal heat transfer fins, and this hydrogen storage module is filled in the tank body. The heat transfer powder layer is used to reduce the pores between the internal heat transfer fins and the alloy and expanded graphite briquettes. A temperature sensor is inserted into the alloy and expanded graphite briquettes to monitor the temperature in real time.

2. The high-efficiency heat and mass transfer alloy hydrogen storage tank according to claim 1, characterized in that: It also includes a pressure gauge, a safety pressure relief valve, and a temperature sensor. The pressure gauge and the safety pressure relief valve are installed on the outside of the tank bottom. The temperature sensor is passed through the tank bottom in a direction parallel to the central axis of the tube body and is sealed to the tank bottom by a ferrule. One end of the temperature sensor is inserted between the alloy and the expanded graphite block, and the temperature sensor passes through part of the hydrogen storage module.

3. The high-efficiency heat and mass transfer alloy hydrogen storage tank according to claim 1, characterized in that: The alloy and expanded graphite compact is formed by pressing hydrogen storage material powder and expanded graphite worms. The mass ratio of the hydrogen storage material powder to the expanded graphite worms is 7 / 3 to 99 / 1, the compaction pressure is 10 MPa to 300 MPa, and the thickness of the alloy and expanded graphite compact is 10 mm to 60 mm. The hydrogen storage material powder in the alloy and expanded graphite compact is a rare earth AB5 type hydrogen storage alloy, a titanium AB2 type hydrogen storage alloy or a Mg-based hydrogen storage alloy, and the particle size of the hydrogen storage material powder ranges from 0.1 mm to 1 mm.

4. The high-efficiency heat and mass transfer alloy hydrogen storage tank according to claim 1, characterized in that: The buckle cover, tube body and tank bottom are made of aluminum alloy or stainless steel. The outer diameter of the tube body is 20mm~100mm, and the wall thickness of the tube body is 3mm~10mm. The filter element is a metal tubular structure processed by powder metallurgy. The diameter of the filter element is 6mm~8mm, the length of the filter element is 30mm~60mm, the pore size of the filter element is 1μm~5μm, and the porosity is 25%~30%.

5. A method for manufacturing a high-efficiency heat and mass transfer alloy hydrogen storage tank according to any one of claims 1 to 4, characterized in that: The steps include: (1) Mixing hydrogen storage material powder and expanded graphite worms in corresponding proportions; (2) After mixing, the mixture is placed in a mold for briquetting to form alloy and expanded graphite briquette of the same thickness; (3) After the briquetting is completed, holes are drilled in the alloy and expanded graphite briquette and the internal heat transfer fins, which are divided into two types: holes passing through the porous stainless steel guide tube and the temperature sensor, and holes only passing through the porous stainless steel guide tube; (4) Weld the gas valve and the filter element at the welding point between the gas valve and the filter element; (5) Weld the tank bottom to the ground, polished and cleaned tube body; (6) After welding is completed, install the pressure gauge and safety relief valve on the bottom of the tank, insert the temperature sensor into the bottom of the tank, and seal it with a ferrule; (7) Fill the bottom of the tank with a layer of heat transfer powder, place the pressed alloy and expanded graphite blocks into the tank, then spread a layer of heat transfer powder, apply thermal conductive glue on the edge of the internal heat transfer fins, and then place the internal heat transfer fins into the tank to complete the filling of one hydrogen storage module. Repeat the above filling process until all hydrogen storage modules are filled; (8) After filling is completed, the porous stainless steel guide tube and the buckle cover are screwed together at the threaded connection between the porous stainless steel guide tube and the buckle cover; (9) Place a rubber ring on the top of the tube body, then insert the combination of the buckle cover and the porous stainless steel guide tube into the tank, and screw the buckle cover and the tube body together at the threaded connection between the buckle cover and the tube body; (10) After the threaded connection is completed, thread the gas valve and filter element assembly to the NPT connector at the threaded connection between the gas valve and the NPT connector; (11) Evacuate the tank through the gas valve, then fill it with argon gas and repeat the purge 2 to 4 times; (12) After the gas washing is completed, close the gas valve and weld the buckle cover and the tube body at the welding point between the buckle cover and the tube body; (13) The external heat exchange fins are then welded to the tube body to complete the production of the hydrogen storage tank.

6. The method for manufacturing a high-efficiency heat and mass transfer alloy hydrogen storage tank according to claim 5, characterized in that: In step (7), heat transfer powder is filled into the bottom of the tank body, one end of the heat transfer powder is in close contact with the bottom of the tank, and the other end of the heat transfer powder is in close contact with the nearest alloy and expanded graphite block.

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