Hydrogen storage device

Abstract

To enable a hydrogen storage tank to be replaced through a simple method.SOLUTION: A vehicle comprises hydrogen storage tank holding devices (8 and 9) which hold a plurality of replaceable hydrogen storage tanks (20) to supply hydrogen to a fuel cell (40). A first pair of hydrogen tanks (20) is selected from the hydrogen storage tanks (20) held with the hydrogen storage tank holding devices (8 and 9) and hydrogen is supplied from both of the first pair of hydrogen storage tanks (20) to the fuel cell (40). When an amount of hydrogen in at least either one of the first pair of hydrogen storage tanks (20) becomes lower than a predetermined hydrogen amount, a second pair of hydrogen storage tanks (20) is selected from the hydrogen storage tanks (20) held with the hydrogen storage tank holding devices (8 and 9) other than the first pair of hydrogen storage tanks (20) and hydrogen is supplied from the second pair of hydrogen storage tanks (20) to the fuel cell (40).SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] The present invention relates to a hydrogen storage device. [Background technology]

[0002] A hydrogen storage device is known in which, in a vehicle powered by a fuel cell, a hydrogen storage tank is held in a removable hydrogen storage case in the trunk at the rear of the vehicle, and when the hydrogen storage case is installed in the trunk, the hydrogen storage tank is connected to the fuel cell via a quick connector (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2009-270707 A Summary of the Invention [Problem to be solved by the invention]

[0004] In this hydrogen storage device, one or more hydrogen storage tanks are connected to a fuel cell, but there is no clear mention of control of the supply of hydrogen from the hydrogen storage tanks to the fuel cell. [Means for solving the problem]

[0005] According to the present invention, there is provided a hydrogen storage device for a vehicle driven by a fuel cell, comprising: a hydrogen storage tank holding device for holding a plurality of replaceable hydrogen storage tanks for supplying hydrogen to the fuel cell; a hydrogen supply control device that controls the supply of hydrogen from the hydrogen storage tank held by the hydrogen storage tank holding device to the fuel cell, A hydrogen storage device is provided in which the hydrogen supply control device has a residual hydrogen amount estimation unit that estimates the amount of remaining hydrogen in the hydrogen storage tank, and the hydrogen supply control device selects a first pair of hydrogen storage tanks from among the hydrogen storage tanks held by the hydrogen storage tank holding device, and causes hydrogen to be supplied from both of the first pair of hydrogen storage tanks to a fuel cell, and when the estimated remaining hydrogen amount in at least one of the first pair of hydrogen storage tanks falls below a set hydrogen amount, selects a second pair of hydrogen storage tanks from among the hydrogen storage tanks held by the hydrogen storage tank holding device other than the first pair of hydrogen storage tanks, and causes hydrogen to be supplied from the second pair of hydrogen storage tanks to the fuel cell and stops the supply of hydrogen from the first pair of hydrogen storage tanks to the fuel cell. Effect of the Invention

[0006] In this way, by configuring the fuel cell to always receive hydrogen from a pair of hydrogen storage tanks, even if, for some reason, hydrogen is not supplied from one of the hydrogen storage tanks to the fuel cell, hydrogen can be supplied from the other hydrogen storage tank to the fuel cell, thereby increasing the likelihood of preventing an interruption in the supply of hydrogen from the hydrogen storage tanks to the fuel cell. [Brief description of the drawings]

[0007] [Figure 1] 1A and 1B are side and top views, respectively, of a schematic representation of a fuel cell powered vehicle. [Diagram 2] FIG. 2A is a schematic side cross-sectional view of a hydrogen storage tank, FIG. 2B is a side view of FIG. 2A, FIG. 2C is a schematic side cross-sectional view of a hydrogen storage tank insertion section, and FIG. 2D is a view showing the hydrogen storage tank inserted into the hydrogen storage tank insertion section. [Diagram 3] FIG. 3 is a diagram showing a hydrogen supply control device. [Figure 4] FIG. 4 is a diagram showing the electronic control device. [Diagram 5]FIG. 5 is a flowchart for performing valve opening control. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] 1A and 1B, which diagrammatically show a vehicle powered by a fuel cell, reference numeral 1 denotes a vehicle body, 2 denotes front wheels, 3 denotes rear wheels, 4 denotes a front room within the vehicle covered by an openable front hood 5, 6 denotes a rear room within the vehicle covered by an openable rear hood 7, 8 denotes a hydrogen storage tank holding device having a plurality of hydrogen storage tank insertion portions 10, and 9 denotes another hydrogen storage tank holding device having a plurality of hydrogen storage tank insertion portions 10. The hydrogen supply control device 8 is supported by the vehicle body 1 in the front room 4, and the hydrogen supply control device 9 is supported by the vehicle body 1 in the rear room 6.

[0009] 1A and 1B, the hydrogen storage tank holding device 8 has six hydrogen storage tank insertion sections 10 arranged in parallel with one another, and the hydrogen storage tank holding device 9 also has six hydrogen storage tank insertion sections 10 arranged in parallel with one another. Furthermore, in the example shown in FIGS. 1A and 1B, each hydrogen storage tank insertion section 10 of the hydrogen storage tank holding device 8 opens toward the top in the forward direction of the vehicle 1, and each hydrogen storage tank insertion section 10 of the hydrogen storage tank holding device 9 opens toward the top in the rear direction of the vehicle 1. The number of hydrogen storage tank insertion sections 10 of the hydrogen storage tank holding device 8 can be set arbitrarily, and the number of hydrogen storage tank insertion sections 10 of the hydrogen storage tank holding device 9 can also be set arbitrarily.

[0010] Figure 2A shows a schematic side cross-sectional view of a hydrogen storage tank 20 to be inserted into either the hydrogen storage tank insertion portion 10 of the hydrogen storage tank holding device 8 shown in Figure 1B or the hydrogen storage tank insertion portion 10 of the hydrogen storage tank holding device 9, and Figure 2B shows a side view of the hydrogen storage tank 20 shown in Figure 2A when viewed from the right. 2A, the hydrogen storage tank 20 is composed of a tank body 21 and a cylindrical casing 22 that surrounds the tank body 21. In the example shown in Fig. 2A, the tank body 21 is filled with high-pressure hydrogen gas. Note that a hydrogen storage alloy can also be placed in the tank body 21.

[0011] A hydrogen outflow section 23 is formed at one end of the tank body 21, i.e., at one end of the hydrogen storage tank 20, and a grip 24 that can be held by hand, i.e., a grip that can be grasped by hand, is formed at the other end of the hydrogen storage tank 20. In the example shown in Figures 2A and 2B, both end faces of the cylindrical casing 22, i.e., both end faces of the hydrogen storage tank 20, are formed from flat surfaces, and the hydrogen outflow section 23 is in the form of a concave cylindrical groove recessed from one flat end face of the hydrogen storage tank 20. Meanwhile, a groove 25 having a circular outline is formed on the other flat end face of the hydrogen storage tank 20, and a grip 24 is formed in the groove 25 so as to be graspable by hand, the grip 24 extending between the opposing upper edges of the groove 25 at a distance from the bottom surface of the groove 25.

[0012] 2A also shows a schematic diagram of a normally closed type outflow control valve 26 arranged in the tank body 21 to control the outflow of hydrogen from the hydrogen outflow portion 23. The outflow control valve 26 normally closes the hydrogen outflow portion 23 by the compressed hydrogen pressure in the tank body 21. Meanwhile, FIG. 2C shows an enlarged side cross-sectional view of the hydrogen storage tank insert 10 shown in FIG. 1A and FIG. 1B. Referring to FIG. 2C, a convex hydrogen inflow portion 28 is formed at the back of the hydrogen storage tank insert 10, protruding into the hydrogen storage tank insert 10 from an end wall 27 covering one end of the hydrogen storage tank insert 10. A hydrogen inflow passage 29 connected to the fuel cell of the vehicle is formed in this convex hydrogen inflow portion 28.

[0013] 2D shows the hydrogen storage tank 20 when it is inserted into the hydrogen storage tank insertion part 10. The hydrogen storage tank 20 is inserted into the hydrogen storage tank insertion part 10 by holding the grip 24 by hand, inserting the end of the hydrogen storage tank 20 where the hydrogen outflow part 23 is formed into the hydrogen storage tank insertion part 10, and pushing the hydrogen storage tank 20 into the hydrogen storage tank insertion part 10. When the hydrogen storage tank 20 is pushed into the hydrogen storage tank insertion part 10, the concave hydrogen outflow part 23 fits into the convex hydrogen inflow part 28. Explaining this from a structural perspective, a guide wall is formed around the hydrogen storage tank insertion portion 10 to guide the concave hydrogen outlet portion 23 of the hydrogen storage tank 20 to the convex hydrogen inlet portion 28 when the hydrogen storage tank 20 is inserted into the hydrogen storage tank insertion portion 10, and when the hydrogen storage tank 20 is inserted into the hydrogen storage tank insertion portion 10, this guide wall guides the concave hydrogen outlet portion 23 of the hydrogen storage tank 20 toward the convex hydrogen inlet portion 28 so that it fits into the convex hydrogen inlet portion 28.

[0014] In this case, this guide wall also plays a role in holding the hydrogen storage tank 20 in a state in which the concave hydrogen outflow portion 23 is fitted into the convex hydrogen inflow portion 28. In the example shown in Figures 2C and 2D, this guide wall is formed of a cylindrical wall. In this case, this guide wall does not necessarily have to be formed of a cylindrical wall, and as this guide wall, for example, in Figure 2D, a guide rod or a guide rod with guide rollers that extends in the longitudinal direction of the hydrogen storage tank insertion portion 10 along the periphery of the hydrogen storage tank 20 can be used.

[0015] On the other hand, the concave hydrogen outflow portion 23 and the convex hydrogen inflow portion 28 have a connection structure in which, after the concave hydrogen outflow portion 23 is fitted into the convex hydrogen inflow portion 28 as shown in Fig. 2D, when the concave hydrogen outflow portion 23 is rotated about the longitudinal center axis of the hydrogen storage tank 20, the concave hydrogen outflow portion 23 is connected to the convex hydrogen inflow portion 28. This connection structure may be, for example, a screw structure in which a screw thread is formed on the inner peripheral surface of the concave hydrogen outflow portion 23 and on the outer peripheral surface of the convex hydrogen inflow portion 28. Therefore, in the example shown in Fig. 2C and Fig. 2D, after the hydrogen storage tank 20 is inserted into the hydrogen storage tank insertion portion 10 and the concave hydrogen outflow portion 23 is fitted into the convex hydrogen inflow portion 28, the grip 24 held by hand is rotated about the longitudinal center axis of the hydrogen storage tank 20, whereby the concave hydrogen outflow portion 23 is connected to the convex hydrogen inflow portion 28.

[0016] On the other hand, when replacing the hydrogen storage tank 20, the grip 24 is grasped by hand and the hydrogen storage tank 20 is rotated to release the connection between the concave hydrogen outflow portion 23 and the convex hydrogen inflow portion 28, and then the hydrogen storage tank 20 is pulled out of the hydrogen storage tank insertion portion 10. A new hydrogen storage tank 20 is inserted into the hydrogen storage tank insertion portion 10. New hydrogen is injected into the pulled out hydrogen storage tank 20 through the hydrogen outflow portion 23 by a hydrogen filling device.

[0017] , In this way, the operation of inserting the hydrogen storage tank 20 into the hydrogen storage tank insertion portion 10 and the operation of connecting the concave hydrogen outflow portion 23 and the convex hydrogen inflow portion 28 can be accomplished by gripping the grip 24, so that the operation of installing and removing the hydrogen storage tank 20 in the hydrogen storage tank holding device 8, i.e., the operation of replacing the hydrogen storage tank 20, can be easily performed. Also, by holding the grip 24 with one hand, the hydrogen storage tank 20 can be easily transported. Also, because both ends of the hydrogen storage tank 20 are formed from flat surfaces, the hydrogen storage tank 20 can be left standing on the floor, and the hydrogen storage tanks 20 can be easily stacked in an upright state. This makes it easy to store the hydrogen storage tank 20.

[0018] Thus, in the embodiment of the present invention, the hydrogen storage device is composed of hydrogen storage tank holding devices 8, 9 supported by a vehicle and having a plurality of hydrogen storage tank insertion sections 10, and replaceable hydrogen storage tanks 20 inserted into each hydrogen storage tank insertion section 10 to supply hydrogen to the vehicle's fuel cell, and a hydrogen inlet section 28 connected to the fuel cell is formed at the back of each hydrogen storage tank insertion section 10. A hydrogen outlet section 23 that is connected to the hydrogen inlet section 28 when the hydrogen storage tank 20 is inserted into the hydrogen storage tank insertion section 10 is formed at one end of each hydrogen storage tank 20, and a grip 24 that can be grasped is formed at the other end of each hydrogen storage tank 20, and the hydrogen storage tank 20 is inserted into the hydrogen storage tank insertion section 10 and the hydrogen inlet section 28 and the hydrogen outlet section 23 are connected by grasping the grip 24. In this case, in the embodiment of the present invention, the hydrogen storage tank 20 is rotated while grasping the grip 24, whereby the hydrogen inlet section 28 and the hydrogen outlet section 23 are connected.

[0019] On the other hand, a valve opening control device 30 that controls the opening of the normally closed outflow control valve 26 is disposed in the convex hydrogen inflow section 28. This valve opening control device 30 is shown diagrammatically in Figs. 2C and 2D. In the example shown in Figs. 2C and 2D, this valve opening control device 30 is composed of a control rod 31 that can engage with the outflow control valve 26 and an actuator 32, for example, a solenoid, for driving the control rod 31. When the solenoid is energized, the control rod 31 abuts against the outflow control valve 26 and pushes up the outflow control valve 26. As a result, the outflow control valve 26 opens, and the high-pressure stored hydrogen in the tank body 21 flows into the hydrogen inflow passage 29 of the hydrogen inflow section 28. When the solenoid is de-energized, the outflow control valve 26 closes, and the outflow of the stored hydrogen from the tank body 21 stops.

[0020] 2A and 2D, a sensor 33 for detecting the state of hydrogen stored in the hydrogen storage tank 20 is disposed at the end of the tank body 21 opposite the hydrogen outflow portion 23, i.e., at the end of the hydrogen storage tank 20 opposite the hydrogen outflow portion 23. This sensor 33 is a sensor that detects at least one of pressure and temperature. In the example shown in FIGS. 2C and 2D, the sensor 33 incorporates a transmitter that transmits a detection signal to the outside. In this case, the detection signal of the sensor 33 can also be transmitted to the outside via a signal line.

[0021] Fig. 3 shows an overall view of the hydrogen supply control device. Fig. 3 shows hydrogen storage tanks 20 inserted into hydrogen storage tank insertion sections 10 of hydrogen storage tank holding devices 8 and 9. In the example shown in Fig. 3, for convenience of explanation, the hydrogen storage tanks 20 inserted into the hydrogen storage tank insertion sections 10 of the hydrogen storage tank holding device 8 are respectively labeled No. 1-A, No. 1-B, No. 2-A, No. 2-B, No. 3-A, and No. 3-B, and the hydrogen storage tanks 20 inserted into the hydrogen storage tank insertion sections 10 of the hydrogen storage tank holding device 9 are respectively labeled No. 4-A, No. 4-B, No. 5-A, No. 5-B, No. 6-A, and No. 6-B.

[0022] As shown in Fig. 3, all of the hydrogen storage tanks 20 are connected to a fuel cell 40 for driving a vehicle via hydrogen inflow passages 29 shown by solid lines, and the valve opening control devices 30 provided in each hydrogen storage tank insertion section 10 are connected to an electronic control device 50 as shown by dashed lines. Meanwhile, Fig. 4 shows the electronic control device 50 of Fig. 3. As shown in Fig. 4, an electronic control unit 51 is provided within this electronic control device 50. This electronic control unit 51 is made up of a digital computer and includes a CPU (microprocessor) 53, a memory 54 consisting of ROM and RAM, and an input / output port 55, which are connected to each other by a bidirectional bus 52.

[0023] The electronic control device 50 is also provided with a communication device 56, which is connected to the electronic control unit 51. Detection signals emitted from the sensors 33 of each hydrogen storage tank 20 are input to the electronic control unit 51 via the communication device 56. As shown in Fig. 4, the valve opening control device 30 is connected to the electronic control unit 51, and the valve opening control of the outflow control valve 26 is performed by the valve opening control device 30 based on an output signal from the electronic control unit 51. A display device 57 having a display screen is also connected to the electronic control unit 51, and the display on the display screen of the display device 57 is controlled based on an output signal from the electronic control unit 51.

[0024] In an embodiment according to the present invention, hydrogen is supplied to the fuel cell 40 from a pair of hydrogen storage tanks 20, and when the amount of residual hydrogen in the pair of hydrogen storage tanks 20 becomes low, a new pair of hydrogen storage tanks 20 starts to supply hydrogen to the fuel cell 40, and the supply of hydrogen to the fuel cell 40 from the pair of hydrogen storage tanks 20 that has been used up until now is stopped. Therefore, The supply of hydrogen to the fuel cell 40 can continue without interruption, and therefore the fuel cell 40 can continue to generate power.

[0025] FIG. 5 shows a valve opening control routine for controlling the opening of the normally closed outflow control valve 26. This routine is repeatedly executed by the electronic control unit 51. 5, first, in step 60, it is determined whether the outflow control valve 26 of the pair of hydrogen storage tanks 20 of No. m is open. Now, assuming that m=1, It is determined whether the outflow control valve 26 of the No. 1-A hydrogen storage tank 20 and the outflow control valve 26 of the No. 1-B hydrogen storage tank 200 are open. If it is determined that the outflow control valve 26 of the pair of hydrogen storage tanks 20 No. m is not open, the process jumps to step 66. On the other hand, if it is determined in step 60 that the outflow control valve 26 of the pair of hydrogen storage tanks 20 No. m is open, the process proceeds to step 61.

[0026] In step 61, the pressure P of the stored hydrogen in the pair of hydrogen storage tanks 20 of No. m detected by the sensor 33 of the pair of hydrogen storage tanks 20 of No. m is acquired. In the example shown in FIG. 5, this pressure P is used as a value for estimating the amount of remaining hydrogen in the hydrogen storage tank 20. Next, in step 62, it is determined whether or not the pressure P of the stored hydrogen in at least one of the pair of hydrogen storage tanks 20 of No. m has dropped below a set pressure PX indicating the allowable limit value of the amount of remaining hydrogen, that is, whether or not the estimated amount of remaining hydrogen in the hydrogen storage tank 20 has dropped below the amount of hydrogen installed. If it is determined that the pressure P of the stored hydrogen in at least one of the pair of hydrogen storage tanks 20 of No. m has not dropped below the set pressure PX, the process jumps to step 66. On the other hand, if it is determined in step 62 that the pressure P of the stored hydrogen in at least one of the pair of hydrogen storage tanks 20 of No. m has dropped below the set pressure PX, the process proceeds to step 63.

[0027] In step 63, the outflow control valve 26 of the pair of hydrogen storage tanks 20 No. m+1 is opened, and then in step 64, the outflow control valve 26 of the pair of hydrogen storage tanks 20 No. m is closed. Next, in step 65, a message indicating that the pair of hydrogen storage tanks 20 No. m need to be replaced is displayed on the display screen of the display device 57, for example, a message indicating that the No. m-A tank and the No. m-B tank need to be replaced. Next, the process proceeds to step 66. In step 66, it is determined whether the pair of hydrogen storage tanks 20 No. m has been replaced. If it is determined that the pair of hydrogen storage tanks 20 No. m has not been replaced, the process jumps to step 68. On the other hand, if it is determined in step 66 that the pair of hydrogen storage tanks 20 No. m has been replaced, the process proceeds to step 67, where the message indicating that the pair of hydrogen storage tanks 20 No. m need to be replaced is terminated. Next, the process proceeds to step 68.

[0028] Furthermore, when the pair of hydrogen storage tanks 20 of each No. m is replaced, for example, the sensor 33 of the hydrogen storage tank 20 transmits information indicating the hydrogen storage tank 20 numbers No. m-A tank and No. m-B tank together with the detection signal so that the detection signal of the sensor 33 of the new pair of hydrogen storage tanks 20 can be recognized as the detection signal of the sensor 33 of the pair of hydrogen storage tanks 20 of No. m, and in step 66, based on this information, it is determined whether the pair of hydrogen storage tanks 20 of No. m has been replaced.

[0029] In step 68, m is incremented by 1, and then in step 69, it is determined whether m has become 7. If it is determined that m=7 is not true, the processing cycle ends. In contrast, if it is determined that m=7, the processing proceeds to step 70, where m is set to 1, and then the processing cycle ends. Therefore, the opening control of the normally closed type outflow control valves 26 of the pair of hydrogen storage tanks No. 1-A, No. 1-B through the pair of hydrogen storage tanks No. 6-A, No. 6-B is repeatedly executed.

[0030] In this way, by controlling the supply of stored hydrogen from the pair of hydrogen storage tanks 20 at all times, even if for some reason one of the hydrogen storage tanks 20 is unable to supply stored hydrogen, the other hydrogen storage tank 20 will supply stored hydrogen. This has the advantage of increasing the possibility of preventing interruptions in the supply of stored hydrogen from the hydrogen storage tanks 20.

[0031] Thus, in this embodiment of the present invention, there is provided a hydrogen supply control device that controls the supply of hydrogen from the hydrogen storage tanks 20 to the fuel cell 40. This hydrogen supply control device has a residual hydrogen amount estimation section that estimates the amount of remaining hydrogen in the hydrogen storage tanks 20, and the hydrogen storage tanks 20 that supply hydrogen to the fuel cell 40 are selected based on the estimated remaining amount of hydrogen in the hydrogen storage tanks 20. In this case, the electronic control unit 51 forms this residual hydrogen amount estimation section.

[0032] Also, in this case, in an embodiment according to the present invention, a pair of hydrogen storage tanks 20 are selected from the hydrogen storage tanks 20 held by the hydrogen storage tank holding devices 8, 9, and hydrogen is supplied from the selected pair of hydrogen storage tanks 20 to the fuel cell 40, and when the estimated residual hydrogen amount in at least one of the selected pair of hydrogen storage tanks 20 falls below the installed hydrogen amount, the next pair of hydrogen storage tanks 20 are selected from the hydrogen storage tanks 20 held by the hydrogen storage tank holding devices 8, 9, and hydrogen is supplied from the next selected pair of hydrogen storage tanks 20 to the fuel cell 40.

[0033] Furthermore, in an embodiment according to the present invention, the hydrogen supply control device has a display device 57 that displays a message indicating that hydrogen storage tank 20 should be replaced when the estimated remaining hydrogen amount in hydrogen storage tank 20 falls below the installed hydrogen amount. Also, in an embodiment according to the present invention, a sensor 33 for detecting the state of stored hydrogen in hydrogen storage tank 20 is disposed on the end side of hydrogen storage tank 20 opposite hydrogen outflow portion 23, and the aforementioned residual hydrogen amount estimation unit estimates the amount of remaining hydrogen in hydrogen storage tank 20 based on the detection signal of sensor 33. [Explanation of symbols]

[0034] 1. Vehicle body 8,9 Hydrogen storage tank holding device 10 Hydrogen storage tank insertion section 20 Hydrogen storage tank 23 Hydrogen Outlet 24 Grip 26 Normally closed spill control valve26 28 Hydrogen inlet 30 Valve opening control device 40 Fuel Cell

Claims

1. In a hydrogen storage device for a vehicle powered by a fuel cell, a hydrogen storage tank holding device for holding a plurality of replaceable hydrogen storage tanks for supplying hydrogen to the fuel cell; a hydrogen supply control device that controls the supply of hydrogen from the hydrogen storage tank held by the hydrogen storage tank holding device to the fuel cell, The hydrogen supply control device has a residual hydrogen amount estimation unit that estimates the amount of remaining hydrogen in the hydrogen storage tank, and the hydrogen supply control device selects a first pair of hydrogen storage tanks from the hydrogen storage tanks held by the hydrogen storage tank holding device and causes hydrogen to be supplied from both of the first pair of hydrogen storage tanks to a fuel cell, and when the estimated remaining hydrogen amount in at least one of the first pair of hydrogen storage tanks falls below a set hydrogen amount, selects a second pair of hydrogen storage tanks from the hydrogen storage tanks held by the hydrogen storage tank holding device other than the first pair of hydrogen storage tanks, and causes hydrogen to be supplied from the second pair of hydrogen storage tanks to the fuel cell and stops the supply of hydrogen from the first pair of hydrogen storage tanks to the fuel cell.

2. The hydrogen supply control device according to claim 1, further comprising a display unit that displays an indication that the first pair of hydrogen storage tanks should be replaced when the estimated remaining hydrogen amount in at least one of the first pair of hydrogen storage tanks falls below a set hydrogen amount.

3. 2. The hydrogen storage device according to claim 1, wherein a sensor for detecting the state of hydrogen stored in the hydrogen storage tank is disposed in the hydrogen storage tank, and the remaining hydrogen amount estimation unit estimates the amount of remaining hydrogen in the hydrogen storage tank based on the detection signal of the sensor.

4. 2. The hydrogen storage device according to claim 1, wherein a normally closed type outflow control valve for controlling the outflow of hydrogen from the hydrogen storage tank is disposed at a hydrogen outflow portion of the hydrogen storage tank, and a valve opening control device for controlling the opening of the outflow control valve is disposed at a hydrogen inflow portion to the fuel cell.

Images