Liquid hydrogen storage device
By configuring an evaporation pipeline at the hydrogen tank port and using vaporized hydrogen to cool the port, the problem of liquid hydrogen vaporization caused by heat input at the port was solved, and the thermal insulation performance of the hydrogen tank was improved.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- TOYOTA JIDOSHA KK
- Filing Date
- 2025-05-19
- Publication Date
- 2026-05-12
AI Technical Summary
The ports of existing liquid hydrogen storage devices cannot be fully insulated, leading to increased heat input, which in turn increases the amount of liquid hydrogen vaporization and affects the insulation performance.
An evaporation line is installed at the port of the hydrogen tank to cool the port using the vaporized, low-temperature hydrogen, thereby reducing heat input.
By using cooling ports, heat input is reduced, the insulation performance of the hydrogen tank is improved, and the amount of evaporated gas discharged is reduced.
Smart Images
Figure CN224229726U_ABST
Abstract
Description
Technical Field
[0001] This disclosure relates to the structure of a liquid hydrogen storage device. Background Technology
[0002] Patent Document 1 discloses a liquid hydrogen storage system, which includes a hydrogen tank for storing liquid hydrogen and piping for releasing hydrogen gas from the tank. The liquid hydrogen stored in the tank partially vaporizes due to natural heat input from the outside air. The vaporized hydrogen gas is released to the outside through the piping.
[0003] Patent Document 1: Japanese Patent Application Publication No. 2024-6562 Utility Model Content
[0004] Problems to be solved by the utility model
[0005] Hydrogen tanks for storing extremely low-temperature liquid hydrogen are equipped with multiple ports, including ports for installing equipment inside the tank and ports for connecting piping for injecting liquid hydrogen. While the hydrogen tanks are designed to be insulated, these ports are sometimes not adequately insulated to allow for the removal of equipment and piping. In such cases, heat input from the ports may increase the amount of liquid hydrogen vaporizing inside the tank.
[0006] Therefore, the purpose of this disclosure is to reduce the amount of heat input from the port to the interior of the hydrogen tank and improve the thermal insulation performance of the hydrogen tank.
[0007] Methods for solving problems
[0008] The liquid hydrogen storage device disclosed herein includes: a hydrogen tank mounted in a vehicle and storing liquid hydrogen; an evaporation line connected to the hydrogen tank and releasing vaporized hydrogen in the hydrogen tank to the outside of the vehicle, characterized in that the hydrogen tank has at least one port protruding from its outer surface, and the evaporation line is configured to surround at least one of the ports.
[0009] Utility Model Effect
[0010] The port is cooled by the low-temperature hydrogen gas vaporized in the hydrogen tank, also known as the evaporating gas, thus reducing the amount of heat input from the port to the interior of the hydrogen tank and improving the insulation performance of the hydrogen tank. Attached Figure Description
[0011] Figure 1 This is a schematic cross-sectional view of the liquid hydrogen storage device according to the embodiment.
[0012] Figure 2 This is a top view of the liquid hydrogen storage device according to the embodiment, and is... Figure 1 The view shown is AA.
[0013] Figure 3 This is a cross-sectional view showing the structure of the pump port and evaporation pipeline of the liquid hydrogen storage device according to the embodiment, and is... Figure 2 The BB cross section shown. Detailed Implementation
[0014] The liquid hydrogen storage device 100 of the embodiment will be described below. Figure 1 As shown, a liquid hydrogen storage device 100 is mounted on a vehicle 200 to store hydrogen in a liquid state. In this case, the vehicle 200 is a vehicle that uses hydrogen as one of its energy sources, such as a fuel cell vehicle or a hydrogen engine vehicle. Hereinafter, an example of a liquid hydrogen storage device 100 suitable for a hydrogen engine vehicle equipped with a direct injection hydrogen engine (not shown) that injects hydrogen directly into the engine cylinder will be described.
[0015] The liquid hydrogen storage device 100 includes a hydrogen tank 10, a hydrogen pump 30, and an evaporation pipeline 40. The hydrogen tank 10 includes a tank body 11, a collector 12, a liquid hydrogen filling port 13, a hydrogen return port 14, an evaporation gas port 15, and a pump port 20.
[0016] The tank body 11 stores liquid hydrogen insulated. The tank body 11 can be, for example, a container with a double-tube structure consisting of an inner tank made of SUS and an outer tank covering the inner tank, with a vacuum insulation layer between them. Furthermore, to maintain a uniform pressure applied to the inner wall, the hydrogen tank 10 is oblong or spherical.
[0017] The liquid hydrogen filling port 13 is installed on the upper side of the tank body 11 and is a port for receiving liquid hydrogen from the outside. In addition, the hydrogen return port 14 is installed on the upper side of the tank body 11 and is used to draw hydrogen gas (so-called vaporized gas) that has been vaporized by natural heat input from the outside and release it to the outside during the filling of liquid hydrogen.
[0018] To properly attract the evaporated gas, the liquid hydrogen level at full filling is below the hydrogen return port 14. Therefore, the internal volume of the hydrogen tank 10 is greater than the capacity of the liquid hydrogen at full filling. Thus, there is always a space above a predetermined volume in the upper part of the hydrogen tank 10 (hereinafter referred to as the "upper space"). Hydrogen gas generated from the vaporization of the liquid hydrogen stored in the tank is retained in this upper space. Therefore, near the top of the tank body 11, i.e., near the upper end of the tank body 11 in the direction of gravity, an evaporated gas port 15 is provided to discharge the evaporated gas retained in the upper part of the tank body 11.
[0019] Pump port 20 is the port for mounting hydrogen pump 30. Pump port 20 includes a nozzle 21 protruding from tank body 11 and a flange 22 mounted on the upper end of nozzle 21.
[0020] Here, the hydrogen pump 30 is a booster pump that draws liquid hydrogen stored in the hydrogen tank 10 and delivers it to the hydrogen engine side. The liquid hydrogen, pressurized by the pump, is vaporized in a vaporizer (not shown) to become high-pressure hydrogen gas. The high-pressure hydrogen gas is then supplied to the hydrogen engine.
[0021] Here, the hydrogen pump 30 consists of a drive unit 31, a mounting flange 32, a shaft 34, and a pump unit 35. The pump unit 35 houses a pump body for pressurizing liquid hydrogen. The shaft 34 houses a drive shaft that connects the drive unit 31 and the pump unit 35. The shaft 34 is connected to the drive unit 31. The mounting flange 32 is connected to the lower end of the drive unit 31. The mounting flange 32 is fastened to the flange 22 of the pump port 20, thereby fixing the drive unit 31 to the tank body 11.
[0022] Collector 12 is disposed on the bottom surface of tank body 11 and is recessed from the periphery. Collector 12 internally houses pump unit 35. Collector 12 can keep pump unit 35 in the liquid even when the remaining liquid hydrogen is low, thereby enabling the liquid hydrogen to be completely drawn out.
[0023] Evaporation line 40 is connected to vaporization gas port 15, through which hydrogen vaporized in hydrogen tank 10 (vaporized gas) is released to the outside of vehicle 200. An electromagnetic safety valve 50 and a reactor 60 are connected to evaporation line 40. Electromagnetic safety valve 50 opens when the pressure in hydrogen tank 10 exceeds a predetermined threshold. Furthermore, reactor 60 reacts hydrogen with air using a catalyst to convert it into water, which is then released to the outside of vehicle 200.
[0024] like Figure 2 , Figure 3 As shown, the evaporation line 40 is configured to surround the nozzle 21 and engage with the lower surface of the flange 22. The evaporation line 40 is mounted to the lower surface of the flange 22 by means of a fixing member 25.
[0025] The structure of the evaporation pipeline 40 and the structure of the fixing component 25 will be described below.
[0026] like Figure 2 As shown, the evaporation pipeline 40 includes an evaporation gas port connection pipe 41, an upstream T-shaped component 42, a cooling pipe 43 on one side and a cooling pipe 44 on the other side, a downstream T-shaped component 45 and a discharge pipe 46.
[0027] The upstream T-shaped member 42 is connected to the evaporation gas port connection pipe 41, one side cooling pipe 43, and the other side cooling pipe 44, causing the hydrogen gas flowing in from the evaporation gas port connection pipe 41 to branch off into the one side cooling pipe 43 and the other side cooling pipe 44. Furthermore, the downstream T-shaped member 45 is connected to the one side cooling pipe 43, the other side cooling pipe 44, and the discharge pipe 46, causing the hydrogen gas flowing in from the one side cooling pipe 43 and the other side cooling pipe 44 to merge in the discharge pipe 46.
[0028] One cooling pipe 43 is bent and surrounds the outer periphery of one side of the nozzle 21 in a reciprocating manner on the outer and inner peripheral sides of the flange 22. Similarly, the other cooling pipe 44 is bent and surrounds the outer periphery of the other side of the nozzle 21 in a reciprocating manner on the outer and inner peripheral sides of the flange 22. The one cooling pipe 43 and the other cooling pipe 44 are configured to be connected and surround the outer periphery of the nozzle 21 by an upstream T-shaped member 42 and a downstream T-shaped member 45.
[0029] like Figure 3 As shown, one cooling pipe 43 and the other cooling pipe 44 are mounted to the lower surface of the flange 22 via a fixing member 25. The fixing member 25 consists of an upper member 26, a lower member 27, a bolt 28A, and a nut 28B. The upper member 26 consists of an upper plate 26A and an upper arm 26B. The lower member 27 consists of a lower plate 27A and a lower arm 27B.
[0030] like Figure 3 As shown, the inner circumference 23 of the flange 22 of the pump port 20 protrudes upwards compared to the outer circumference, and a circumferential groove 24 is provided in the inner circumference 23. On the other hand, the mounting flange 32 of the hydrogen pump 30 has an annular protrusion 33 on its lower surface. Furthermore, the protrusion 33 is configured to seal by flattening the sealing member 39 disposed in the groove 24. Therefore, when the mounting flange 32 is mounted on the flange 22 and tightened with bolts 36, a vertical gap exists between the mounting flange 32 and the outer circumference of the flange 22.
[0031] The upper plate 26A is a circular plate component mounted on the upper surface of the flange 22 by entering the gap. The upper arm 26B is a plate component with multiple parts arranged in the circumferential direction and extending downward from the upper plate 26A. The lower plate 27A can be, for example, a component formed by connecting a semi-circular ring component on one side to a semi-circular ring component on the other side. The lower plate 27A is positioned below the cooling pipe 43 on one side and the cooling pipe 44 on the other side. The lower arm 27B is a plate component with multiple parts arranged in the circumferential direction and extending downward from the lower plate 27A. The upper arm 26B and the lower arm 27B are combined by bolts 28A and nuts 28B. Thus, the cooling pipe 43 on one side and the cooling pipe 44 on the other side are sandwiched between the lower surface of the flange 22 and the lower plate 27A, and are mounted to the pump port 20 in such a way that the upper part contacts the lower surface of the flange 22.
[0032] When the pressure of the hydrogen gas remaining in the upper part of the tank body 11 exceeds a predetermined threshold, the electromagnetic safety valve 50 opens. Hydrogen gas then flows from the vapor port 15 into one cooling pipe 43 and the other cooling pipe 44. The hydrogen gas is extremely cold, and its flow through the cooling pipes 43 and 44 cools the flange 22 and the nozzle 21. This reduces heat input from the flange 22 and nozzle 21 into the hydrogen tank 10, improving the insulation performance of the hydrogen tank 10. Consequently, the amount of vapor gas discharged to the outside of the vehicle 200 is reduced.
[0033] The above description illustrates that the evaporator line 40 is configured to surround the pump port 20, but it is not limited to this configuration. For example, it can also be configured to surround the liquid hydrogen filling port 13 and the hydrogen return port 14 in addition to the pump port 20. This reduces heat input from the liquid hydrogen filling port 13 and the hydrogen return port 14 into the hydrogen tank 10, thereby further improving the thermal insulation performance of the hydrogen tank 10. As a result, the amount of evaporated gas discharged to the outside of the vehicle 200 can be further reduced.
[0034] Symbol Explanation
[0035] 10…Hydrogen tank; 11…Tank body; 12…Collector; 13…Liquid hydrogen filling port; 14…Hydrogen return port; 15…Evaporated gas port; 20…Pump port; 21…Nozzle; 22…Flange; 23…Inner circumference; 24…Gate; 25…Fixing component; 26…Upper component; 26A…Upper plate; 26B…Upper arm; 27…Lower component; 27A…Lower plate; 27B…Lower arm; 28A…Bolt; 28B…Nut; 30…Hydrogen pump ; 31… Drive unit; 32… Mounting flange; 33… Protrusion; 34… Shaft; 35… Pump unit; 36… Bolt; 39… Sealing component; 40… Evaporation pipeline; 41… Evaporation gas port connection pipe; 42… Upstream T-shaped component; 43… One-side cooling pipe; 44… The other-side cooling pipe; 45… Downstream T-shaped component; 46… Discharge pipe; 50… Electromagnetic safety valve; 60… Reactor; 100… Liquid hydrogen storage device; 200… Vehicle.
Claims
1. A liquid hydrogen storage device, comprising: Hydrogen tanks, which are mounted in vehicles, store liquid hydrogen; An evaporation line, connected to the hydrogen tank, releases the vaporized hydrogen in the tank to the outside of the vehicle. The liquid hydrogen storage device is characterized in that... The hydrogen tank has at least one port protruding from its outer surface. The evaporation line is configured to surround at least one of the ports.