Fuel cell system

Abstract

To provide a fuel cell system that can stably secure hydrogen gas at the concentration necessary for power generation using a fuel cell. [Solution] One aspect of the present disclosure provides a fuel cell system 1 comprising a first pressure sensor P1 for measuring the pressure between a hydrogen storage alloy canister 41 and an injector 42 in a hydrogen gas supply passage 31, and a control unit 13 for controlling an exhaust and drain valve 51. The control unit 13 controls the number of opening and closing operations of the exhaust and drain valve 51 per unit time to be greater than when the measured value of the first pressure sensor P1 is higher than the measured value of the first pressure sensor P1 is higher than the predetermined pressure PA.

Description

Technical Field

[0001] The present disclosure relates to a fuel cell system having a fuel cell that generates electricity by receiving supplies of a fuel gas and an oxidant gas.

Background Art

[0002] Patent Document 1 discloses a fuel cell system that supplies hydrogen gas released from a hydrogen storage alloy canister (hydrogen storage alloy) to a fuel cell to generate electricity in the fuel cell.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the fuel cell system disclosed in Patent Document 1, when the temperature of the hydrogen storage alloy canister is low, the discharge pressure of hydrogen gas from the hydrogen storage alloy canister (that is, the pressure of the hydrogen gas released from the hydrogen storage alloy canister) becomes low, and the supply amount of hydrogen gas to the fuel cell decreases, and there is a possibility that hydrogen gas at a concentration necessary for power generation in the fuel cell cannot be ensured.

[0005] Therefore, the present disclosure has been made to solve the above-described problems, and an object thereof is to provide a fuel cell system that can stably ensure hydrogen gas at a concentration necessary for power generation in a fuel cell.

Means for Solving the Problems

[0006] One embodiment of the present disclosure made to solve the above problems is a fuel cell system comprising: a fuel cell; a hydrogen gas supply passage for supplying hydrogen gas to the fuel cell; a hydrogen storage container filled with a hydrogen storage alloy and releasing the hydrogen gas into the hydrogen gas supply passage; a hydrogen supply device disposed in the hydrogen gas supply passage and supplying the hydrogen gas released from the hydrogen storage container to the fuel cell; a hydrogen off-gas discharge passage for discharging hydrogen off-gas discharged from the fuel cell to the outside; and an exhaust control valve disposed in the hydrogen off-gas discharge passage for controlling the discharge of the hydrogen off-gas to the outside, wherein the hydrogen storage container and the hydrogen gas in the hydrogen gas supply passage The device comprises at least one of a pressure measuring unit for measuring the pressure between the supply device and the hydrogen storage container, and a container temperature measuring unit for measuring the temperature of the hydrogen storage container, and a control unit for controlling the exhaust control valve, wherein the control unit controls the number of opening and closing operations of the exhaust control valve per unit time to be greater than when the measured value of the pressure measuring unit is higher than the predetermined pressure when the measured value of the pressure measuring unit is lower than the predetermined pressure, and / or controls the number of opening and closing operations of the exhaust control valve per unit time to be greater than when the measured value of the container temperature measuring unit is higher than the predetermined container temperature when the measured value of the container temperature measuring unit is lower than the predetermined container temperature.

[0007] According to this embodiment, when the temperature of the hydrogen storage container decreases and the discharge pressure of hydrogen gas from the hydrogen storage alloy canister decreases, resulting in low pressure between the hydrogen storage container and the hydrogen supply device in the hydrogen gas supply passage, the number of times the exhaust control valve is opened and closed per unit time is increased. This improves the efficiency of discharging nitrogen and water generated by power generation in the fuel cell, thereby increasing the concentration of hydrogen gas in the fuel cell. As a result, a stable supply of hydrogen gas at the concentration necessary for power generation can be secured in the fuel cell.

[0008] Furthermore, as the fuel cell generates electricity, it produces heat, which can then be transferred to the hydrogen storage container. This warms the hydrogen storage container, increasing the discharge pressure of the hydrogen gas and thus increasing the pressure between the hydrogen storage container and the hydrogen supply device in the hydrogen gas supply passage. Consequently, the amount of hydrogen gas supplied to the fuel cell increases, ensuring a stable supply of hydrogen gas at the concentration necessary for power generation.

[0009] In the above embodiment, it is preferable that the control unit controls the exhaust control valve to increase the number of opening and closing operations by shortening the closing time of the exhaust control valve.

[0010] According to this embodiment, when increasing the number of opening and closing operations of the exhaust control valve, shortening the closing time of the exhaust control valve makes it more difficult for hydrogen gas to be emitted from the fuel cell than shortening the opening time, thus increasing the concentration of hydrogen gas in the fuel cell.

[0011] In the above embodiment, the system includes a fan that blows heat generated by the fuel cell toward the hydrogen storage container, and a battery temperature measuring unit that measures the temperature of the fuel cell. The control unit controls the fan, and preferably, the control unit operates the fan when the measurement value from the battery temperature measuring unit is above a predetermined battery temperature, and stops the fan when the measurement value from the battery temperature measuring unit is below the predetermined battery temperature.

[0012] According to this embodiment, when the fuel cell is warmed up and its temperature is high, a fan is activated to send the heat generated by the fuel cell to the hydrogen storage container. This increases the efficiency of hydrogen gas release from the hydrogen storage container. As a result, the amount of hydrogen gas supplied from the hydrogen storage container to the fuel cell can be increased.

[0013] On the other hand, if the fuel cell is not warmed up and its temperature is low, the fan is stopped to prevent cold air from being sent to the hydrogen storage container. This prevents a decrease in the efficiency of hydrogen gas release from the hydrogen storage container. Therefore, the reduction in the amount of hydrogen gas supplied from the hydrogen storage container to the fuel cell can be suppressed. [Effects of the Invention]

[0014] According to the fuel cell system of this disclosure, it is possible to stably secure hydrogen gas at the concentration necessary for power generation using a fuel cell. [Brief explanation of the drawing]

[0015] [Figure 1] This is a diagram illustrating the configuration of the fuel cell system (open cathode type system) of this embodiment. [Figure 2] This is a characteristic diagram of the temperature, hydrogen pressure, and hydrogen concentration of a hydrogen storage alloy canister. [Figure 3] This diagram shows that the FC stack, hydrogen storage alloy canister, and battery are arranged inside the case. [Figure 4] This is a flowchart illustrating the control process performed in this embodiment. [Figure 5] This is a diagram illustrating a modified fuel cell system (closed cathode system). [Modes for carrying out the invention]

[0016] Embodiments of the fuel cell system described herein will be explained.

[0017] (Fuel cell system configuration) As shown in Figure 1, the fuel cell system 1 of this embodiment includes an FC stack 11 (air-cooled FC stack), a battery 12 (secondary battery), a hydrogen system 21, and an air-cooling system 22. The FC stack 11 is an example of a "fuel cell" as disclosed herein.

[0018] The FC stack 11 generates electricity by receiving the supply of fuel gas and oxidant gas. In this embodiment, the fuel gas is hydrogen gas and the oxidant gas is air (i.e., atmosphere). That is, the FC stack 11 generates electricity by receiving the supply of hydrogen gas from the hydrogen system 21 and the supply of air from the air / cooling system 22. Then, the electric power generated by the FC stack 11 is supplied to the battery 12 and an inverter and a motor (not shown).

[0019] The battery 12 is connected to the FC stack 11 and charges the electric power generated by the FC stack 11. Note that this battery 12 supplies electric power to an inverter and a motor (not shown).

[0020] The hydrogen system 21 is provided on the anode side of the FC stack 11. This hydrogen system 21 includes a hydrogen gas supply passage 31 and a hydrogen off-gas discharge passage 32.

[0021] The hydrogen gas supply passage 31 is a passage for supplying hydrogen gas from the hydrogen storage alloy canister 41 in which hydrogen gas is stored to the FC stack 11. The hydrogen off-gas discharge passage 32 is a passage for discharging the hydrogen gas (i.e., hydrogen off-gas) discharged from the FC stack 11.

[0022] Also, as shown in FIGS. 1 and 2, the hydrogen system 21 includes, in the hydrogen gas supply passage 31, a hydrogen storage alloy canister 41, and in order from the hydrogen storage alloy canister 41 side, a first pressure sensor P1, an injector 42, and a second pressure sensor P2.

[0023] Note that the hydrogen storage alloy canister 41 is an example of the "hydrogen storage container" of the present disclosure. Also, the first pressure sensor P1 is an example of the "pressure measurement unit" of the present disclosure. Also, the injector 42 is an example of the "hydrogen supply device" of the present disclosure.

[0024] The hydrogen storage alloy canister 41 is a container filled with a hydrogen storage alloy that has the properties of absorbing and releasing hydrogen gas. In other words, the hydrogen storage alloy canister 41 is filled with a hydrogen storage alloy and can release hydrogen gas into the hydrogen gas supply passage 31 or absorb hydrogen gas from a hydrogen tank (not shown).

[0025] The first pressure sensor P1 measures the pressure between the hydrogen storage alloy canister 41 and the injector 42 in the hydrogen gas supply passage 31 (i.e., the discharge pressure of the hydrogen storage alloy canister 41). The injector 42 is a device that injects and supplies hydrogen gas released from the hydrogen storage alloy canister 41 to the downstream FC stack 11. The second pressure sensor P2 measures the outlet pressure of the injector 42 (i.e., the injection pressure).

[0026] Furthermore, the hydrogen system 21 is equipped with an exhaust drain valve 51 in the hydrogen off-gas discharge passage 32 that controls the switching between discharging and blocking hydrogen off-gas and moisture to the outside. The exhaust drain valve 51 is an example of the "exhaust control valve" of this disclosure.

[0027] On the other hand, the air and cooling system 22 is located on the cathode side of the FC stack 11. This air and cooling system 22 includes an air supply passage 61, an air-off gas discharge passage 62, and a fan 63.

[0028] The air supply passage 61 is a passage for supplying air from outside the fuel cell system 1 to the FC stack 11. The air-off gas discharge passage 62 is a passage for discharging air (i.e., air-off gas) discharged from the FC stack 11.

[0029] The fan 63 supplies air to the FC stack 11 via the air supply passage 61 and discharges air-off gas from the FC stack 11 via the air-off gas discharge passage 62.

[0030] In this embodiment, the fan 63 not only supplies air to the FC stack 11 via the air supply passage 61, thereby enabling the FC stack 11 to generate electricity, but also serves to cool the FC stack 11. Thus, the fuel cell system 1 shown in Figure 1 is an open cathode system that uses the air supplied to the FC stack 11 by the fan 63 as a cooling gas for the FC stack 11.

[0031] Furthermore, the fuel cell system 1 includes a first temperature sensor T1, a second temperature sensor T2, and a third temperature sensor T3. The first temperature sensor T1 measures the temperature of the FC stack 11. The second temperature sensor T2 measures the temperature of the hydrogen storage alloy canister 41. The third temperature sensor T3 measures the temperature of the battery 12. The first temperature sensor T1 is an example of the "battery temperature measuring unit" in this disclosure. The second temperature sensor T2 is an example of the "container temperature measuring unit" in this disclosure.

[0032] Furthermore, the fuel cell system 1 has a control unit 13. The control unit 13 is a device that includes, for example, an arithmetic processing unit such as a CPU, a storage unit such as a ROM that stores control programs and control data processed by the CPU, and a RAM used as various work areas for control processing, and an input / output interface unit. The control unit 13 then performs various controls on the fuel cell system 1 according to the control programs stored in the storage unit.

[0033] In this embodiment, the control unit 13 controls various components of the fuel cell system 1, including the injector 42, exhaust and drain valve 51, fan 63, and cooling fan 71 (described later). The control unit 13 also obtains the measured discharge pressure of the hydrogen storage alloy canister 41 from the first pressure sensor P1 and the measured outlet pressure of the injector 42 from the second pressure sensor P2. Furthermore, the control unit 13 obtains the measured temperature of the FC stack 11 from the first temperature sensor T1, the measured temperature of the hydrogen storage alloy canister 41 from the second temperature sensor T2, and the measured temperature of the battery 12 from the third temperature sensor T3.

[0034] (Fuel cell system operation) In the fuel cell system 1 configured as described above, the hydrogen gas supplied to the FC stack 11 from the hydrogen gas supply passage 31 is used for power generation in the FC stack 11, and then discharged from the FC stack 11 as hydrogen off-gas to the outside of the fuel cell system 1 via the hydrogen off-gas discharge passage 32. Similarly, the air supplied to the FC stack 11 from the air supply passage 61 is used for power generation in the FC stack 11, and then discharged from the FC stack 11 as air off-gas to the outside of the fuel cell system 1 via the air off-gas discharge passage 62.

[0035] Furthermore, the electricity generated by the FC stack 11 is used to charge the battery 12 or supplied to an inverter and motor (not shown).

[0036] (Measures to ensure the necessary concentration of hydrogen gas for power generation in the fuel cell stack) The hydrogen gas discharge pressure (i.e., the pressure of the hydrogen gas released from the hydrogen storage alloy canister 41) of the hydrogen storage alloy canister 41 changes with temperature. As shown in Figure 2, the lower the temperature of the hydrogen storage alloy canister 41 (shown as 0°C, 20°C, 40°C, and 60°C in the figure), the lower the hydrogen gas discharge pressure (indicated as "hydrogen pressure" in the figure). For example, if the temperature of the hydrogen storage alloy canister 41 is 20°C or lower, the hydrogen gas discharge pressure drops to 20kPaG to 150kPaG. When the hydrogen gas discharge pressure of the hydrogen storage alloy canister 41 decreases, the amount of hydrogen gas supplied to the FC stack 11 decreases, and there is a risk that the FC stack 11 may not be able to secure hydrogen gas at the concentration necessary for power generation.

[0037] Therefore, in this embodiment, measures are taken to ensure a stable supply of hydrogen gas at the concentration necessary for power generation in the FC stack 11, regardless of the temperature of the hydrogen storage alloy canister 41. Specifically, if the temperature of the hydrogen storage alloy canister 41 is low and the discharge pressure of hydrogen gas from the hydrogen storage alloy canister 41 is low, the temperature of the hydrogen storage alloy canister 41 is increased by using the heat generated when the FC stack 11 is warmed up, thereby increasing the discharge pressure of hydrogen gas from the hydrogen storage alloy canister 41. This increases the amount of hydrogen gas supplied to the FC stack 11, ensuring that a hydrogen gas concentration necessary for power generation is secured in the FC stack 11.

[0038] More specifically, as shown in Figure 3, in this embodiment, the FC stack 11, the hydrogen storage alloy canister 41, and the battery 12 are arranged in a case 81 that surrounds them, thereby modularizing them. A cooling fan 71 is provided near the FC stack 11, and the hydrogen storage alloy canister 41 is positioned relative to the FC stack 11 via the cooling fan 71. Note that the cooling fan 71 is just one example of a "fan" in this disclosure.

[0039] The control unit 13 then performs the control shown in Figure 4. As shown in Figure 4, the control unit 13 determines whether the measurement value of the first pressure sensor P1 (i.e., the measurement value of the hydrogen gas discharge pressure of the hydrogen storage alloy canister 41) is less than or equal to a predetermined pressure PA (for example, 60 kPaG) (step S1).

[0040] Then, if the measurement value of the first pressure sensor P1 is less than or equal to a predetermined pressure PA (step S1: YES), the control unit 13 first controls the outlet pressure of the injector 42 to a target pressure (for example, 60 kPaG) (step S2).

[0041] Next, the control unit 13 operates the exhaust and drain valve 51 frequently (for example, open for 200ms and closed for 500ms) (step S3). Note that "open for 200ms and closed for 500ms" means that the valve is kept open for 200ms and then closed for 500ms, and this cycle is repeated.

[0042] In this manner, when the measurement value of the first pressure sensor P1 is below a predetermined pressure PA and the discharge pressure of hydrogen gas from the hydrogen storage alloy canister 41 is low, the control unit 13 controls the discharge pressure of the injector 42 to the target pressure and operates the exhaust drain valve 51 frequently, increasing the number of opening and closing operations of the exhaust drain valve 51 per unit time compared to when the measurement value of the first pressure sensor P1 is higher than the predetermined pressure PA.

[0043] At this time, the control unit 13 controls the exhaust drain valve 51 to increase the number of opening and closing operations per unit time by shortening the closing time of the exhaust drain valve 51 compared to when performing the normal control in step S7 described later. This increases the efficiency of the discharge of nitrogen and water (by the exhaust drain valve 51) generated by power generation in the FC stack 11, thereby increasing the concentration of hydrogen gas in the FC stack 11.

[0044] As a variation, the control unit 13 may control the number of opening and closing operations of the exhaust drain valve 51 per unit time to be higher when the measurement value of the second temperature sensor T2 is below a predetermined temperature TB (for example, 10°C) than when the measurement value of the second temperature sensor T2 is higher than the predetermined temperature TB. Here, the predetermined temperature TB is an example of the "predetermined container temperature" in this disclosure.

[0045] Next, the control unit 13 determines whether the measurement value of the first temperature sensor T1 is equal to or greater than a predetermined temperature TA (for example, 30°C) (step S4). The predetermined temperature TA is an example of the "predetermined battery temperature" in this disclosure.

[0046] Then, if the measurement value of the first temperature sensor T1 is equal to or greater than a predetermined temperature TA (step S4: YES), the control unit 13 activates the cooling fan 71 (step S5).

[0047] In this way, if the measurement value of the first temperature sensor T1 is above a predetermined temperature TA and the temperature of the FC stack 11 is high, the cooling fan 71 is activated. As a result, the heat generated when the FC stack 11 warms up is blown by the cooling fan 71 towards the hydrogen storage alloy canister 41. In this way, the heat generated when the FC stack 11 warms up can be used to warm the hydrogen storage alloy canister 41. Therefore, the discharge pressure of hydrogen gas from the hydrogen storage alloy canister 41 can be increased.

[0048] In this embodiment, since the FC stack 11, hydrogen storage alloy canister 41, and battery 12 are arranged inside the case 81, the heat generated when the FC stack 11 warms up can be used to raise the temperature inside the case 81, thereby simultaneously warming the hydrogen storage alloy canister 41 and the battery 12.

[0049] On the other hand, if the measurement value of the first temperature sensor T1 is less than the predetermined temperature TA (step S4: NO), the control unit 13 stops the cooling fan 71 (step S6).

[0050] In this way, if the measurement value of the first temperature sensor T1 is below a predetermined temperature TA and the temperature of the FC stack 11 is low, the cooling fan 71 is stopped. This prevents the hydrogen storage alloy canister 41 from being cooled by the air blown by the cooling fan 71.

[0051] Furthermore, if the measurement value of the first pressure sensor P1 is greater than the predetermined pressure PA (step S1: NO), the control unit 13 performs normal control (step S7).

[0052] In this manner, when the hydrogen gas discharge pressure from the hydrogen storage alloy canister 41 is high, the control unit 13, as a normal control, controls the outlet pressure of the injector 42 to a target pressure (e.g., 60 kPaG), repeatedly keeps the exhaust drain valve 51 open for 200 ms and closed for 10 seconds, and controls the cooling fan 71 according to the State of Charge (SOC) of the battery 12 to perform power generation (continuous power generation) and stop power generation (intermittent stop).

[0053] This embodiment can also be applied to a modified fuel cell system 2 shown in Figure 5. This fuel cell system 2 is a closed-cathode system and, as shown in Figure 5, has an air system 122 and a cooling system 123.

[0054] The air system 122 is located on the cathode side of the FC stack 11. This air system 122 includes an air supply passage 161 and an air-off gas discharge passage 162.

[0055] The air supply passage 161 is a passage for supplying air to the FC stack 11 from outside the fuel cell system 1. The air-off gas discharge passage 162 is a passage through which air-off gas, which is air not used for power generation, is discharged from the FC stack 11.

[0056] The air system 122 includes an air compressor 171 and an inlet air valve 172 in the air supply passage 161. The air compressor 171 is a device that supplies air to the FC stack 11. The inlet air valve 172 is located downstream of the air compressor 171 in the airflow and is a valve that controls the flow rate of air supplied to the FC stack 11.

[0057] Furthermore, the air system 122 includes an outlet air valve 173 in the air-off gas discharge passage 162. The outlet air valve 173 is a valve that controls the flow rate of air-off gas discharged from the FC stack 11 to the air-off gas discharge passage 162.

[0058] The cooling system 123 is a system for cooling the FC stack 11 and includes a cooling water passage 201 and a cooling fan 202. The cooling water passage 201 is a passage through which cooling water flows. The cooling fan 202 is a device that cools the cooling water flowing through the cooling water passage 201.

[0059] In this fuel cell system 2, the control unit 13 controls the air compressor 171, the inlet air valve 172, the outlet air valve 173, and the cooling fan 202.

[0060] In the fuel cell system 2 configured as described above, in the air system 122, the air supplied to the FC stack 11 from the air supply passage 161 is used for power generation in the FC stack 11, and then discharged to the outside as air-off gas from the FC stack 11 via the air-off gas discharge passage 162.

[0061] (Effects of this embodiment) As described above, according to this embodiment, when the measured value of the first pressure sensor P1 is less than or equal to a predetermined pressure PA, the control unit 13 controls the number of opening and closing operations of the exhaust drain valve 51 per unit time to be greater than when the measured value of the first pressure sensor P1 is higher than the predetermined pressure PA.

[0062] In this way, when the temperature of the hydrogen storage alloy canister 41 decreases and the hydrogen gas discharge pressure decreases, the number of times the exhaust drain valve 51 is opened and closed per unit time is increased when the pressure between the hydrogen storage alloy canister 41 and the injector 42 in the hydrogen gas supply passage 31 is low. This increases the efficiency of the discharge of nitrogen and water (by the exhaust drain valve 51) generated by power generation in the FC stack 11, and increases the concentration of hydrogen gas in the FC stack 11. As a result, a stable supply of hydrogen gas at the concentration necessary for power generation can be secured in the FC stack 11.

[0063] Furthermore, as power generation in the FC stack 11 is accelerated and the FC stack 11 generates heat, the heat generated in the FC stack 11 can be transferred to the hydrogen storage alloy canister 41. As a result, the hydrogen storage alloy canister 41 is heated, increasing the discharge pressure of hydrogen gas from the hydrogen storage alloy canister 41, and thus increasing the pressure between the hydrogen storage alloy canister 41 and the injector 42 in the hydrogen gas supply passage 31. Consequently, the amount of hydrogen gas supplied to the FC stack 11 increases, ensuring a stable supply of hydrogen gas at the concentration necessary for power generation in the FC stack 11.

[0064] Furthermore, the control unit 13 controls the exhaust drain valve 51 to increase the number of opening and closing operations by shortening the closing time of the valve.

[0065] In this way, when increasing the number of opening and closing operations of the exhaust drain valve 51, shortening the closing time of the exhaust drain valve 51 makes it more difficult for hydrogen gas to be discharged from the FC stack 11 than shortening the opening time, thus increasing the concentration of hydrogen gas in the FC stack 11.

[0066] Furthermore, the control unit 13 activates the cooling fan 71 if the measurement value of the first temperature sensor T1 is above a predetermined temperature TA. On the other hand, the control unit 13 stops the cooling fan 71 if the measurement value of the first temperature sensor T1 is below the predetermined temperature TA.

[0067] In this way, when the FC stack 11 is warmed up and its temperature is high, the cooling fan 71 is activated to send the heat generated in the FC stack 11 to the hydrogen storage alloy canister 41. As a result, the hydrogen storage alloy canister 41 is warmed up and its temperature rises, which increases the efficiency of hydrogen gas release from the hydrogen storage alloy canister 41. Therefore, the amount of hydrogen gas supplied from the hydrogen storage alloy canister 41 to the FC stack 11 can be increased.

[0068] On the other hand, if the FC stack 11 is not warmed up and its temperature is low, the cooling fan 71 is stopped to prevent cold air from being sent to the hydrogen storage alloy canister 41. This prevents the hydrogen storage alloy canister 41 from being cooled, thus preventing a decrease in the efficiency of hydrogen gas release from the hydrogen storage alloy canister 41. Therefore, a decrease in the amount of hydrogen gas supplied from the hydrogen storage alloy canister 41 to the FC stack 11 can be prevented.

[0069] It should be noted that the embodiments described above are merely illustrative examples and do not limit this disclosure in any way. Various improvements and modifications are possible without departing from the gist of the disclosure. [Explanation of symbols]

[0070] 1,2 Fuel cell systems 11 FC stack 12 batteries 13 Control Unit 21 Hydrogen-based systems 31 Hydrogen gas supply channel 32 Hydrogen off-gas emission channel 41 Hydrogen storage alloy canister 42 Injectors 51 Exhaust drain valve 71 Cooling fan 81 cases P1 First pressure sensor PA (Prescribed Pressure) T1 First temperature sensor T2 Second temperature sensor TA Predetermined temperature TB Predetermined temperature

Claims

1. Fuel cells and A hydrogen gas supply passage for supplying hydrogen gas to the fuel cell, A hydrogen storage container filled with a hydrogen storage alloy and releasing the hydrogen gas into the hydrogen gas supply passage, A hydrogen supply device is arranged in the hydrogen gas supply passage and supplies the hydrogen gas released from the hydrogen storage container to the fuel cell. A hydrogen off-gas discharge passage for discharging hydrogen off-gas from the fuel cell to the outside, An exhaust control valve is provided in the hydrogen off-gas discharge passage and controls the discharge of the hydrogen off-gas to the outside, In a fuel cell system having, A pressure measuring unit for measuring the pressure between the hydrogen storage container and the hydrogen supply device in the hydrogen gas supply passage, and at least one of a container temperature measuring unit for measuring the temperature of the hydrogen storage container, It includes a control unit that controls the exhaust control valve, The control unit, When the pressure measurement value of the pressure measuring unit is below a predetermined pressure, the number of opening and closing operations of the exhaust control valve per unit time is controlled to be higher than when the pressure measurement value of the pressure measuring unit is higher than the predetermined pressure. and / or, When the measurement value of the container temperature measuring unit is below a predetermined container temperature, the number of opening and closing operations of the exhaust control valve per unit time is controlled to be higher than when the measurement value of the container temperature measuring unit is above the predetermined container temperature. A fuel cell system characterized by the following.

2. In the fuel cell system of claim 1, The control unit controls the exhaust control valve to increase the number of opening and closing operations by shortening the closing time of the exhaust control valve. A fuel cell system characterized by the following.

3. In the fuel cell system of claim 1 or 2, A fan that blows the heat generated by the fuel cell toward the hydrogen storage container, It has a battery temperature measuring unit for measuring the temperature of the fuel cell, The control unit controls the fan, The control unit, If the measurement value of the battery temperature measuring unit is above a predetermined battery temperature, the fan will be activated. If the measurement value of the battery temperature measuring unit is below the predetermined battery temperature, the fan will be stopped. A fuel cell system characterized by the following.

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