Solid hydrogen storage tank based on heat self-balancing type and heat control method

Abstract

The invention belongs to the field of hydrogen storage technology heat management, and provides a heat self-balancing type solid hydrogen storage tank and a heat control method. The solid hydrogen storage tank based on the heat self-balancing type comprises a tank body, a flange cover, a hydrogen storage-heat storage unit, a U-shaped pipe and a gas guide pipe, the flange cover is hermetically connected with the upper opening end of the tank body; a hydrogen inlet / outlet is formed in the flange cover; the hydrogen storage-heat storage unit is arranged in the tank body and consists of a hydrogen storage layer and a heat storage layer; the at least two U-shaped pipes are inserted into the hydrogen storage-heat storage unit and are circumferentially distributed; the gas guide pipes are divided into a main gas guide pipe and a plurality of branch gas guide pipes which are circumferentially distributed and are used for guiding hydrogen to be uniformly distributed and circulated in the hydrogen storage layer; one end of the main gas guide pipe is connected with the hydrogen inlet and outlet, penetrates out of the tank body and is used for being connected with a hydrogen source; the other end of the main gas guide pipe is communicated with a plurality of branch gas guide pipes, and the branch gas guide pipes are inserted into the hydrogen storage layer, penetrate into the hydrogen storage layer and are circumferentially distributed.

Description

Technical Field

[0001] The present invention belongs to the field of thermal management of hydrogen storage technology, and in particular relates to a solid-state hydrogen storage tank based on thermal self-balancing and a thermal control method. Background Art

[0002] The statements in this section merely provide background information related to the present invention and do not necessarily constitute prior art.

[0003] Proton exchange membrane fuel cells using hydrogen as fuel have the advantages of high energy density, long power supply time, fast startup speed and low operating temperature. However, how to achieve safe and efficient hydrogen storage is a technical bottleneck restricting the development of hydrogen fuel cells. Metal hydride hydrogen storage has many advantages such as low hydrogen storage pressure, high volume hydrogen storage density, good safety performance and simple hydrogen storage and release process. It is suitable for small and medium-sized hydrogen fuel cell power generation systems and is one of the most promising hydrogen storage methods.

[0004] The process of storing and releasing hydrogen in metal hydrides is accompanied by significant thermal effects, causing their temperature to change and deviate from the appropriate temperature conditions for the reaction. Integrating phase change materials in metal hydride hydrogen storage tanks has the potential to achieve self-thermal management without the need for external heat sources. However, the inherent thermal conductivity of phase change materials is low, and the heat transfer area of ​​traditional sleeve-type hydrogen storage tanks coupled with phase change materials is limited and cannot meet application requirements, which leads to low heat transfer efficiency. Although built-in heat exchangers with different structures are conducive to improving the heat transfer rate, the released reaction heat is directly discharged by the heat exchange fluid and cannot be effectively recycled. In this context, the coupled thermal management method combining built-in heat exchangers and phase change materials can not only ensure heat exchange efficiency, but also help improve energy utilization.

[0005] However, the existing technology generally believes that the built-in heat exchanger and phase change material work independently in the metal hydride hydrogen storage tank. Therefore, how to effectively combine the interaction between the two and coordinate the interaction between the two has become one of the key challenges to improve hydrogen storage performance and optimize thermal management efficiency. In addition, for the melting process of phase change materials, it is affected by the combined effects of natural convection and heat conduction. On the one hand, natural convection will increase the melting rate, but on the other hand, it will also cause the melting rate of the upper part of the phase change area to be faster than that of the lower part, thereby causing non-uniform melting and thermal stratification, which is not conducive to the heat and mass transfer behavior in the metal hydride hydrogen storage tank coupled with the phase change material. Summary of the invention

[0006] In order to solve the technical problems existing in the above-mentioned background technology, the purpose of the present invention is to provide a solid-state hydrogen storage tank and a heat control method based on thermal self-balancing, which can solve the high energy consumption problem in the thermal management of solid-state hydrogen storage tanks and improve the thermal stratification phenomenon in metal hydride hydrogen storage tanks coupled with phase change materials.

[0007] In order to achieve the above object, the present invention adopts the following technical solution:

[0008] A first aspect of the present invention provides a solid-state hydrogen storage tank based on thermal self-balancing type.

[0009] A solid-state hydrogen storage tank based on heat self-balancing type, comprising: a tank body, a flange cover, a hydrogen storage-heat storage unit, a U-shaped tube and an air guide tube;

[0010] The flange cover is sealed and connected to the upper open end of the tank body; a hydrogen inlet and outlet are provided on the flange cover; the hydrogen storage-heat storage unit is arranged in the tank body and is composed of a hydrogen storage layer and a heat storage layer; the heat storage layer is coated on the outside of the hydrogen storage layer in the form of a jacket;

[0011] At least two of the U-shaped tubes are inserted into the hydrogen storage-heat storage unit and are distributed in a circumference; one end of the U-shaped tube is located in the hydrogen storage layer, and the other end is located in the heat storage layer; both ends of the U-shaped tube pass through the outside of the flange cover and are connected to an external power pump; a heat exchange fluid flows inside the U-shaped tube;

[0012] The air guide pipe is divided into a main air guide pipe and a plurality of branch air guide pipes distributed in a circle, and is used to guide the hydrogen to be evenly distributed and circulated in the hydrogen storage layer; one end of the main air guide pipe is connected to the hydrogen inlet and outlet and passes through the tank body to be connected to a hydrogen source; the other end of the main air guide pipe is connected to a plurality of branch air guide pipes, and the branch air guide pipes are inserted into the hydrogen storage layer and penetrate into the interior thereof, and are distributed in a circle.

[0013] As an implementation manner, the number of the hydrogen storage-heat storage units is set to at least two, and the hydrogen storage-heat storage units are sequentially wrapped around the outside of other hydrogen storage-heat storage units in the form of outer jackets.

[0014] As an implementation mode, the number of U-shaped tubes inserted in each of the hydrogen storage-heat storage units is the same and are all distributed in a circular pattern.

[0015] As an implementation mode, a main air pipe is placed at the center of each hydrogen storage-heat storage unit and an equal number of branch air pipes are placed around the unit in a circumferential distribution.

[0016] As an implementation mode, the hydrogen storage layer is filled with metal hydride hydrogen storage material for storing hydrogen; the heat storage layer is filled with composite phase change material for recovering reaction heat in the hydrogen storage process and utilizing it in the hydrogen release process.

[0017] As an implementation mode, a graphite gasket for sealing is provided at the connection between the flange cover and the tank body.

[0018] As an implementation mode, a thermocouple inserted into the tank body is welded on the flange cover, and the thermocouple is used to monitor the temperature change inside the tank body during the storage and release of hydrogen; or a pressure sensor and a pressure relief valve are connected to the flange cover, and the pressure sensor is used to detect the change of hydrogen pressure in the tank body, and the pressure relief valve is used to relieve the pressure when the pressure in the storage tank exceeds the safety pressure.

[0019] A second aspect of the present invention provides a heat control method for a solid-state hydrogen storage tank based on a heat self-balancing type.

[0020] A heat control method based on the heat self-balancing solid-state hydrogen storage tank as described above comprises:

[0021] During the hydrogen storage process, the hydrogen in the hydrogen source enters the hydrogen storage tank through the gas pipe, diffuses into the hydrogen storage layer, reacts with the metal hydride hydrogen storage material in the hydrogen storage layer to absorb hydrogen and releases reaction heat; part of the reaction heat is transferred through the wall between the hydrogen storage layer and the heat storage layer, and the other part is driven by the power pump to extract the heat exchange fluid flowing in the U-tube from the hydrogen storage layer and transfer it to the heat storage layer for storage;

[0022] Subsequently, during the hydrogen decomposition process, in addition to transferring the heat required for the hydrogen decomposition reaction through the wall between the hydrogen storage layer and the heat storage layer, the power pump drives the heat exchange fluid to extract the stored reaction heat from the heat storage layer and transfer it to the hydrogen storage layer as a heat source for the hydrogen decomposition reaction; the metal hydride hydrogen storage material absorbs heat and undergoes a hydrogen decomposition reaction, and the released hydrogen is released from the hydrogen storage tank through the gas duct and supplied to the hydrogen fuel cell as fuel.

[0023] As an implementation method, when the hydrogen demand is less than the set value or in the cold start, the power pump is controlled to be turned off. At this time, heat exchange is carried out only through the contact surface between the hydrogen storage layer and the heat storage layer in the hydrogen storage tank; when the hydrogen demand is greater than or equal to the set value, the power pump is controlled to be turned on. At this time, heat transfer is carried out in the hydrogen storage tank through the circulating flow of the heat exchange fluid in the U-tube and the contact surface of the hydrogen storage layer.

[0024] As an implementation method, according to the demand for hydrogen supply rate of the hydrogen fuel cell, the hydrogen outlet pressure and the flow rate of the heat exchange fluid are regulated to meet the hydrogen demand under different working conditions.

[0025] The beneficial effects of the present invention are:

[0026] (1) The present invention provides a solid-state hydrogen storage tank based on thermal self-balancing, which adopts a sandwich structure in which hydrogen storage layers and heat storage layers are alternately distributed. The heat exchange efficiency can be effectively improved by increasing the heat exchange area. The reaction heat is recovered and reused through the melting and solidification process of the phase change material in the hydrogen storage tank, which solves the high energy consumption problem in the thermal management of the solid-state hydrogen storage system and improves the energy utilization rate of the hydrogen storage and degassing process.

[0027] (2) The present invention adopts a U-shaped tube to connect the hydrogen storage layer and the heat storage layer, thereby improving the effective heat transfer coefficient inside the hydrogen storage tank. Through the flow heat transfer of the heat exchange fluid in the U-shaped tube and the heat storage function of the PCM, the efficient recovery and reuse of the reaction heat and the self-heating balance of the hydrogen storage tank are achieved, which greatly improves the thermal energy utilization efficiency and the hydrogen storage and desorption performance.

[0028] (3) In order to solve the problems of thermal stratification and heat accumulation in the hydrogen storage tank, the present invention proposes to load composite phase change materials with different foam metal contents along the heat flow direction of the heat storage layer in the solid hydrogen storage tank. The foam metal content in the top area with large heat flux density is relatively low, while the foam metal content in the bottom area with small heat flux density is relatively high. This distribution method is conducive to improving the uniformity of temperature distribution and ensuring that all areas of the hydrogen storage layer obtain the same degree of heat exchange efficiency, thereby improving the hydrogen storage and desorption efficiency.

[0029] (4) The present invention provides a heat control method based on a heat self-balancing solid-state hydrogen storage tank. The controller adjusts the hydrogen outlet pressure and the flow rate of the heat exchange fluid to meet the heat exchange requirements of the solid-state hydrogen storage tank under different working conditions, thereby achieving a wide range of hydrogen supply rate regulation.

[0030] (5) In order to improve the problem of uneven contact time between hydrogen and hydrogen storage materials caused by a single hydrogen inlet and outlet, the present invention evenly arranges multiple air guide pipes in the hydrogen storage layer, so that hydrogen can enter or discharge the hydrogen storage tank more quickly and evenly, greatly shortening the response time.

[0031] Advantages of additional aspects of the present invention will be given in part in the following description, and in part will become obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] The accompanying drawings in the specification, which constitute a part of the present invention, are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute improper limitations on the present invention.

[0033] Figure 1 A schematic diagram of a three-dimensional structure of a heat self-balancing solid-state hydrogen storage tank according to an embodiment of the present invention;

[0034] Figure 2 This is a diagram of the internal heat exchange structure of a heat self-balancing solid-state hydrogen storage tank according to an embodiment of the present invention;

[0035] Figure 3 A schematic diagram of a two-dimensional structure of a heat self-balancing solid-state hydrogen storage tank according to an embodiment of the present invention;

[0036] Figure 4 This is a structural diagram of an air guide pipe in a heat self-balancing solid-state hydrogen storage tank according to an embodiment of the present invention;

[0037] Figure 5 This is a distribution diagram of air ducts in a heat self-balancing solid-state hydrogen storage tank according to an embodiment of the present invention;

[0038] Figure 6 A schematic diagram of a tank body of a heat self-balancing solid-state hydrogen storage tank according to an embodiment of the present invention;

[0039] Figure 7 This is a schematic diagram of a support structure in a heat self-balancing solid-state hydrogen storage tank according to an embodiment of the present invention;

[0040] Figure 8 The present invention is a flow chart of a method for controlling heat of a solid-state hydrogen storage tank based on heat self-balancing.

[0041] In the figure, 1-tank body; 2-flange cover; 21-hydrogen inlet and outlet; 22-graphite gasket; 3-hydrogen storage-heat storage unit; 31-hydrogen storage layer; 32-heat storage layer; 321-first composite phase change material; 322-second composite phase change material; 323-third composite phase change material; 4-U-shaped tube; 5-support structure; 6-air guide tube; 61-main air guide tube; 62-sub-air guide tube. DETAILED DESCRIPTION

[0042] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0043] It should be noted that the following detailed descriptions are all illustrative and intended to provide further explanation of the present invention. Unless otherwise specified, all technical and scientific terms used herein have the same meanings as those commonly understood by those skilled in the art to which the present invention belongs.

[0044] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit exemplary embodiments according to the present invention. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprising" and / or "including" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0045] In the present invention, terms such as "upper", "lower", "left", "right", "front", "back", "vertical", "horizontal", "side", "bottom", etc. indicate directions or positional relationships based on the directions or positional relationships shown in the accompanying drawings. They are relational words determined only for the convenience of describing the structural relationships of the various parts or elements of the present invention, and do not specifically refer to any part or element in the present invention and should not be understood as limitations on the present invention.

[0046] In the present invention, terms such as "fixed connection", "connected", "connection", etc. should be understood in a broad sense, indicating that it can be fixedly connected, integrally connected or detachably connected; it can be directly connected or indirectly connected through an intermediate medium. Relevant scientific research or technical personnel in this field can determine the specific meanings of the above terms in the present invention according to specific circumstances, and they should not be understood as limiting the present invention.

[0047] The present invention provides a solid-state hydrogen storage tank and a heat control method based on heat self-balancing to solve the high energy consumption problem in the thermal management of the solid-state hydrogen storage system and improve the thermal stratification phenomenon in the hydrogen storage system, thereby improving the overall performance and hydrogen storage and desorption efficiency.

[0048] Embodiment 1

[0049] In this embodiment, if Figure 1-Figure 7 As shown, a solid-state hydrogen storage tank based on heat self-balancing type is provided, comprising: a tank body 1, a flange cover 2, a hydrogen storage-heat storage unit 3, a U-shaped tube 4 and an air guide tube 6; the flange cover 2 is sealed and connected to the upper open end of the tank body 1; a hydrogen inlet and outlet 21 is provided on the flange cover 2; the hydrogen storage-heat storage unit 3 is arranged in the tank body 1, and is composed of a hydrogen storage layer 31 and a heat storage layer 32; the heat storage layer 32 is coated on the outside of the hydrogen storage layer 31 in the form of a jacket;

[0050] like Figure 2 and Figure 3 As shown, at least two of the U-shaped tubes 4 are inserted into the hydrogen storage-heat storage unit 3 and are distributed in a circle; one end of the U-shaped tube 4 is located in the hydrogen storage layer 31, and the other end is located in the heat storage layer 32; both ends of the U-shaped tube 4 pass through the outside of the flange cover 2 and are connected to an external power pump; a heat exchange fluid circulates inside the U-shaped tube 4 to achieve efficient transfer and recycling of reaction heat; wherein the heat exchange fluid includes but is not limited to one of a single-phase heat exchange fluid or a phase change convection heat exchange fluid, such as water, air, molten salt, heat transfer oil and refrigerant, and the heat exchange fluid is preferably water.

[0051] like Figure 4 and Figure 5 As shown, the air guide pipe 6 is divided into a main air guide pipe 61 and a plurality of branch air guide pipes 62 distributed in a circle, which are used to guide the hydrogen to be evenly distributed and circulated in the hydrogen storage layer 31; one end of the main air guide pipe 61 is connected to the hydrogen inlet and outlet 21 and passes through the tank body 1 to connect to the hydrogen source; the other end of the main air guide pipe 61 is connected to a plurality of branch air guide pipes 62, which are inserted into the hydrogen storage layer 31 and penetrate into the interior thereof, and are distributed in a circle.

[0052] In order to ensure the safety of the main air pipe, the main air pipe 61 passes through the outside of the tank body 1 and is also provided with a safety valve.

[0053] In one or more embodiments, the number of the hydrogen storage-heat storage units 3 is set to at least two, and the hydrogen storage-heat storage units 3 are sequentially wrapped around the outside of other hydrogen storage-heat storage units 3 in the form of outer jackets.

[0054] For example, in this embodiment, the number of hydrogen storage-heat storage units 3 is two, and one hydrogen storage-heat storage unit 3 is wrapped around the outside of another hydrogen storage-heat storage unit 3 in the form of a jacket.

[0055] The number of U-shaped tubes 4 inserted into each of the hydrogen storage-heat storage units 3 is the same (for example, 5, and the number can be set according to actual conditions), and they are all distributed in a circular pattern.

[0056] It should be noted here that the geometric shape of the U-shaped tube 4 includes but is not limited to a straight tube, a corrugated tube, a spiral tube, etc., and is preferably a straight tube.

[0057] In order to prevent the U-shaped tube 4 from shaking and shifting in the tank body 1, it needs to be fixed. Preferably, a circular hole can be opened on the flange cover 2, and the U-shaped tube 4 can be firmly connected to the flange cover 2 with bolts to enhance its stability. At the same time, a certain amount of extra space is reserved at the bottom of the tank body 1 for placing a supporting structure or a buffer device to accommodate thermal expansion and provide additional support to ensure the safety and reliability of the operation of the hydrogen storage tank.

[0058] In this embodiment, a main air pipe 61 is placed in the center of the first hydrogen storage-heat storage unit, and the same number (for example, 5) of circumferentially distributed branch air pipes 62 are placed around the first hydrogen storage-heat storage unit and the second hydrogen storage-heat storage unit.

[0059] In order to alleviate the problems of non-uniform melting and thermal stratification caused by natural convection, the heat storage layer 32 is filled with composite phase change materials with different porosity sizes in order from top to bottom along the axial direction, and the uniformity of temperature distribution is improved by changing the foam metal content with the heat flow distribution, thereby ensuring that the metal hydride hydrogen storage material has the same degree of heat exchange efficiency in all areas. Preferably, the porosity is 0.95, 0.9, and 0.85, respectively, that is, the content of foam metal in the heat storage layer 32 gradually increases from top to bottom.

[0060] The wall of the air duct is made of porous material with high thermal conductivity, including but not limited to foam metal, and a plurality of pores are opened along the axial direction for circulating hydrogen.

[0061] In other embodiments, the outer layer of the air guide tube is covered with a filter layer for intercepting impurities and filtering hydrogen, and the pore size of the filter layer is not greater than 5um.

[0062] In the specific implementation process, the hydrogen storage layer 31 is filled with metal hydride hydrogen storage materials for storing hydrogen; wherein the metal hydride hydrogen storage materials include but are not limited to one or a combination of LaNi5, Mg, Mg2Ni or MgH2.

[0063] In the specific implementation process, the heat storage layer 32 is filled with a composite phase change material to recover reaction heat during the hydrogen storage process and utilize it during the hydrogen release process. For example, the composite phase change material includes a first composite phase change material 321 , a second composite phase change material 322 and a third composite phase change material 323 .

[0064] Among them, the composite phase change material is a uniform composite of phase change material and foam metal, the phase change material includes but is not limited to one or a combination of paraffin, fatty acid, salt, trihydrate LiNO3·3H2O and other materials; the foam metal includes but is not limited to one or a combination of foam copper, foam nickel, foam aluminum and other materials, preferably foam copper with high thermal conductivity and high specific surface area.

[0065] Preferably, when the metal hydride hydrogen storage material selects the rare earth AB5 metal LaNi5 with the advantages of moderate reaction pressure, room temperature hydrogen absorption and desorption, and easy activation, the melting point of the selected phase change material should be between the reaction equilibrium temperatures corresponding to the hydrogen absorption and desorption pressures of LaNi5. The operating pressures of hydrogen absorption and desorption are 10 bar and 3 bar respectively. The melting point of LiNO3·3H2O matches the equilibrium temperature of LaNi5 absorption and desorption of hydrogen under the selected pressure. Compared with other phase change materials, LiNO3·3H2O has a larger latent heat of fusion (296 kJ / kg) and requires less volume, resulting in a higher hydrogen storage density per unit volume.

[0066] In some optional embodiments, a graphite gasket 22 for sealing is provided at the connection between the flange cover 2 and the tank body 1 .

[0067] In one or more embodiments, a thermocouple inserted into the tank body 1 is welded on the flange cover 2, and the thermocouple is used to monitor the temperature change inside the tank body 1 during the hydrogen storage and release process;

[0068] The flange cover 2 is connected with a pressure sensor and a pressure relief valve. The pressure sensor is used to detect the change of hydrogen pressure in the tank body 1, and the pressure relief valve is used to release the pressure when the pressure in the tank exceeds the safety pressure.

[0069] like Figure 1 and Figure 7 As shown, a supporting structure 5 is also provided at the bottom of the tank body 1 .

[0070] This embodiment adopts a sandwich structure with alternating distribution of hydrogen storage layers and heat storage layers. By increasing the heat exchange area, the heat exchange efficiency can be effectively improved. Through the melting and solidification process of the phase change material in the hydrogen storage tank, the reaction heat is recovered and reused, which solves the high energy consumption problem in the thermal management of the solid-state hydrogen storage system and improves the energy utilization rate of the hydrogen storage and dehydrogenation process. In addition, by filling the composite phase change material with different foam metal contents in the solid-state hydrogen storage tank along the heat flow direction of the heat storage layer, the heat stratification and heat accumulation problems in the hydrogen storage tank are solved, thereby improving the hydrogen storage and dehydrogenation efficiency.

[0071] Embodiment 2

[0072] In this embodiment, if Figure 8 As shown, a heat control method based on the heat self-balancing solid-state hydrogen storage tank as described above is provided, comprising:

[0073] During the hydrogen storage process, the hydrogen in the hydrogen source enters the hydrogen storage tank through the gas pipe, diffuses into the hydrogen storage layer, reacts with the metal hydride hydrogen storage material in the hydrogen storage layer to absorb hydrogen and releases reaction heat; part of the reaction heat is transferred through the wall between the hydrogen storage layer and the heat storage layer, and the other part is driven by the power pump to extract the heat exchange fluid flowing in the U-tube from the hydrogen storage layer and transfer it to the heat storage layer for storage;

[0074] Subsequently, during the hydrogen decomposition process, in addition to transferring the heat required for the hydrogen decomposition reaction through the wall between the hydrogen storage layer and the heat storage layer, the power pump drives the heat exchange fluid to extract the stored reaction heat from the heat storage layer and transfer it to the hydrogen storage layer as a heat source for the hydrogen decomposition reaction; the metal hydride hydrogen storage material absorbs heat and undergoes a hydrogen decomposition reaction, and the released hydrogen is released from the hydrogen storage tank through the gas duct and supplied to the hydrogen fuel cell as fuel.

[0075] In this way, during the entire process, the heat transfer of the heat exchange fluid in the U-shaped tube running through the hydrogen storage layer and the heat storage layer and the heat storage function of the phase change material are used to achieve efficient recovery and reuse of the reaction heat, greatly improving the thermal energy utilization efficiency and hydrogen storage performance.

[0076] When the hydrogen demand is less than the set value or cold start occurs, the power pump is controlled to be turned off. At this time, heat exchange is carried out only through the contact surface between the hydrogen storage layer and the heat storage layer in the hydrogen storage tank; when the hydrogen demand is greater than or equal to the set value, the power pump is controlled to be turned on. At this time, heat transfer is carried out in the hydrogen storage tank through the circulating flow of the heat exchange fluid in the U-tube and the contact surface of the hydrogen storage layer.

[0077] In one or more embodiments, according to the demand for hydrogen supply rate of the hydrogen fuel cell, the hydrogen outlet pressure and the flow rate of the heat exchange fluid are regulated to meet the hydrogen demand under different working conditions. In this way, the heat exchange demand of the solid hydrogen storage tank under different working conditions is met by adjusting the hydrogen outlet pressure and the flow rate of the heat exchange fluid through the controller, thereby realizing a wide range of hydrogen supply rate regulation.

[0078] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A solid-state hydrogen storage tank based on heat self-balancing type, characterized in that: include: Tank body, flange cover, hydrogen storage-heat storage unit, U-shaped tube and air guide tube; The flange cover is sealed and connected to the upper open end of the tank body; a hydrogen inlet and outlet are provided on the flange cover; the hydrogen storage-heat storage unit is arranged in the tank body and is composed of a hydrogen storage layer and a heat storage layer; the heat storage layer is coated on the outside of the hydrogen storage layer in the form of a jacket; At least two of the U-shaped tubes are inserted into the hydrogen storage-heat storage unit and are distributed in a circumference; one end of the U-shaped tube is located in the hydrogen storage layer, and the other end is located in the heat storage layer; both ends of the U-shaped tube pass through the outside of the flange cover and are connected to an external power pump; a heat exchange fluid flows inside the U-shaped tube; The air guide pipe is divided into a main air guide pipe and a plurality of branch air guide pipes distributed in a circle, and is used to guide the hydrogen to be evenly distributed and circulated in the hydrogen storage layer; one end of the main air guide pipe is connected to the hydrogen inlet and outlet and passes through the tank body to be connected to a hydrogen source; the other end of the main air guide pipe is connected to a plurality of branch air guide pipes, and the branch air guide pipes are inserted into the hydrogen storage layer and penetrate into the interior thereof, and are distributed in a circle.

2. The heat self-balancing solid-state hydrogen storage tank according to claim 1 is characterized in that: The number of the hydrogen storage-heat storage units is set to at least two, and the hydrogen storage-heat storage units are sequentially wrapped around the outside of other hydrogen storage-heat storage units in the form of jackets.

3. The solid-state hydrogen storage tank based on heat self-balancing type as claimed in claim 2 is characterized in that: The number of U-shaped tubes inserted in each of the hydrogen storage-heat storage units is the same and all are distributed in a circular pattern.

4. The heat self-balancing solid-state hydrogen storage tank according to claim 2 is characterized in that: A main air pipe is placed at the center of each hydrogen storage-heat storage unit, and an equal number of branch air pipes distributed in a circumference are placed around it.

5. The solid-state hydrogen storage tank based on heat self-balancing type as claimed in claim 1 is characterized in that: The hydrogen storage layer is filled with metal hydride hydrogen storage material for storing hydrogen; or the heat storage layer is filled with composite phase change material for recovering reaction heat in the hydrogen storage process and utilizing it in the hydrogen release process.

6. The heat self-balancing solid-state hydrogen storage tank according to claim 1, characterized in that: A graphite gasket for sealing is arranged at the connection between the flange cover and the tank body.

7. The solid-state hydrogen storage tank based on heat self-balancing type as claimed in claim 1 is characterized in that: A thermocouple inserted into the tank body is welded on the flange cover, and the thermocouple is used to monitor the temperature change inside the tank body during the hydrogen storage and release process; or a pressure sensor and a pressure relief valve are connected to the flange cover, and the pressure sensor is used to detect the change of hydrogen pressure in the tank body, and the pressure relief valve is used to relieve the pressure when the pressure in the storage tank exceeds the safety pressure.

8. A heat control method based on a heat self-balancing solid hydrogen storage tank according to any one of claims 1 to 7, characterized in that: include: During the hydrogen storage process, the hydrogen in the hydrogen source enters the hydrogen storage tank through the gas pipe, diffuses into the hydrogen storage layer, reacts with the metal hydride hydrogen storage material in the hydrogen storage layer to absorb hydrogen and releases reaction heat; part of the reaction heat is transferred through the wall between the hydrogen storage layer and the heat storage layer, and the other part is driven by the power pump to extract the heat exchange fluid flowing in the U-tube from the hydrogen storage layer and transfer it to the heat storage layer for storage; Subsequently, during the hydrogen desorption process, in addition to transferring the heat required for the hydrogen desorption reaction through the wall between the hydrogen storage layer and the heat storage layer, the power pump drives the heat exchange fluid to extract the stored reaction heat from the heat storage layer and transfer it to the hydrogen storage layer as a heat source for the hydrogen desorption reaction; the metal hydride hydrogen storage material absorbs heat and undergoes a hydrogen desorption reaction, and the released hydrogen is released from the hydrogen storage tank through the gas duct and supplied to the hydrogen fuel cell as fuel.

9. The heat control method according to claim 8, characterized in that: When the hydrogen demand is less than the set value or cold start occurs, the power pump is controlled to be turned off. At this time, heat exchange is carried out only through the contact surface between the hydrogen storage layer and the heat storage layer in the hydrogen storage tank; when the hydrogen demand is greater than or equal to the set value, the power pump is controlled to be turned on. At this time, heat transfer is carried out in the hydrogen storage tank through the circulating flow of the heat exchange fluid in the U-tube and the contact surface of the hydrogen storage layer.

10. The heat control method according to claim 8, characterized in that: According to the hydrogen supply rate requirement of the hydrogen fuel cell, the hydrogen outlet pressure and the flow rate of the heat exchange fluid are regulated to meet the hydrogen demand under different working conditions.

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