Fuel cell system

Abstract

To provide a fuel cell system that can suppress performance degradation and deterioration of partial cells in a fuel cell stack in which multiple single cells are stacked.SOLUTION: A fuel cell system according to an embodiment of the present disclosure includes a fuel cell stack grouped into a plurality of sections each composed of one or more cells, a control device that manages the state of the cell for each of the plurality of sections, and a flow rate adjustment mechanism that adjusts the flow rate of the fluid flowing in each of the plurality of sections on the basis of state management by the control device, and the control device performs the grouping such that the number of cells in a first section constituting the plurality of sections and the number of cells in a second section different from the first section are different from each other.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present disclosure relates to a fuel cell system applied to, for example, vehicles and the like.

Background Art

[0002] In modern society, for example, automobiles are indispensable as means of transportation, and various vehicles travel on roads in daily life. In recent years, fuel cells with relatively low environmental impact have attracted attention.

[0003] In such a fuel cell, hydrogen is supplied to one electrode (fuel electrode) and oxygen is supplied to the other electrode (air electrode), and electric energy is obtained through the reaction of these gases. Condition management of the fuel cell is important for obtaining electric energy efficiently while reducing loss. For example, in the following patent document, the above-described condition management is performed in a fuel cell system including a fuel cell stack in which a plurality of unit cells are stacked, by dividing the plurality of unit cells into a plurality of groups and measuring the impedance of each group.

Prior Art Literature

Patent Literature

[0004]

Patent Literature 1

Patent Literature 2

Summary of the Invention

Problem to be Solved by the Invention

[0005] Not limited to each of the above-mentioned patent documents, it cannot be said that current technology appropriately satisfies market needs, and there are problems described below. In other words, according to the state management of fuel cell systems proposed in the aforementioned patent document, it is indeed possible to perform detailed state management by dividing multiple single cells into several groups and measuring the impedance of each. However, the prior art, including the aforementioned patent document, does not mention how to divide the multiple single cells into groups that are appropriate for the fuel cell as a whole, and there is still considerable room for improvement in how these groups are divided.

[0006] This disclosure has been made in view of the above-mentioned problems as an example, and aims to provide a fuel cell system that can suppress partial performance degradation and deterioration of cells in a fuel cell stack in which multiple single cells are stacked. [Means for solving the problem]

[0007] To solve the above problems, a fuel cell system in one embodiment of the present disclosure is grouped into multiple sections, each consisting of one or more cells. The above-mentioned multiple sections generate electricity in parallel. A fuel cell stack, a control device that manages the state of the cells for each of the multiple sections, and a flow rate adjustment mechanism that adjusts the flow rate of the fluid circulating in each of the multiple sections based on the state management by the control device, A sensor that acquires environmental information around the fuel cell stack, Equipped with, The plurality of sections that generate power in parallel include at least a first section and a second section different from the first section, The control device is The aforementioned The grouping is performed such that the number of cells in the first section and the number of cells in the second section are different from each other. Furthermore, based on the acquired environmental information and at least one of the internal state of the cell, the grouped section is regrouped. cormorant. [Effects of the Invention]

[0008] According to the fuel cell system of this disclosure, it is possible to suppress partial performance degradation and deterioration of cells in a fuel cell stack in which multiple single cells are stacked. [Brief explanation of the drawing]

[0009] [Figure 1] This is an overall block diagram of the fuel cell system according to the first embodiment. [Figure 2]It is a schematic diagram of the fuel cell according to the first embodiment. [Figure 3] It is a block diagram of a control device in the fuel cell system according to the first embodiment. [Figure 4] It is a schematic diagram showing an oxidizing gas supply system in the fuel cell system according to the first embodiment. [Figure 5] It is a flowchart showing a state management method for the fuel cell system according to the first embodiment. [Figure 6] It is a schematic diagram showing an example of cell grouping performed by the control device according to the first embodiment. [Figure 7] It is a schematic diagram showing an example of cell regrouping performed by the control device according to the first embodiment. [Figure 8] It is a diagram showing an example of fluid flow rate adjustment performed by the flow rate adjustment mechanism according to the first embodiment. [Figure 9] It is an overall block diagram of the fuel cell system according to the second embodiment. [Figure 10] It is an overall block diagram of a fuel cell system in a modified example. DETAILED DESCRIPTION OF THE INVENTION

[0010] Next, preferred embodiments for carrying out the present disclosure will be described. For configurations not described in detail below, elemental techniques and configurations related to known fuel cell systems, including the above-mentioned patent documents, may be supplemented as appropriate.

[0011] <First Embodiment> [Fuel Cell System 100] First, the configuration of a fuel cell system 100 according to a preferred embodiment of the present disclosure will be described with reference to FIG. 1. The fuel cell system 100 in the present embodiment may be mounted on, for example, a fuel cell vehicle (FCV).

[0012] Hereinafter, the case of an FCV is described as an application example of the fuel cell system 100, but the present disclosure is not limited to FCVs, and is also suitable for stationary fuel cell systems such as those for housing facilities and fuel cell systems mounted on other moving bodies such as aircraft.

[0013] A fuel cell system 100 mounted on an FCV includes a control device 20 for controlling the vehicle (such as an ECU 20A and other known ECUs), a fuel cell stack 10 controlled by the control device 20, and a gas supply system 50 that supplies anode gas and cathode gas to the fuel cell stack 10. In addition, the fuel cell system 100 of the present embodiment includes a known CMU (Cell Management Unit) 20B that manages the state of the fuel cell stack 10. As described above, the control device 20 that controls the vehicle in the present embodiment may be configured to include the above-described ECU 20A and CMU 20B.

[0014] Among these components, the gas supply system 50 of the present embodiment includes a known hydrogen tank 51 that supplies hydrogen gas to the anode electrode side of the fuel cell stack 10, a fuel gas intake pipe 52, a fuel gas exhaust pipe 53, and the like. The gas supply system 50 also includes a known air compressor 54 serving as cathode gas supply means that supplies air to the cathode electrode side of the fuel cell stack 10, an air intake pipe 55, an air exhaust pipe 56, and the like. Under the control of the control device 20, the flow rates of the cathode gas and the anode gas can be adjusted by known flow rate adjusting valves V1 to V3, respectively.

[0015] Although description thereof is omitted in the present embodiment, various known mechanisms such as a humidifier, a hydrogen gas recirculation mechanism (not shown), or a pressure regulating valve, as exemplified in the above-mentioned patent documents, may be included in the gas supply system 50. In addition, a refrigerant flow path through which a known refrigerant for cooling the fuel cell stack 10 flows is formed inside the fuel cell stack 10 of the present embodiment, but in FIG. 1, this refrigerant flow path and a known refrigerant circulation system for circulating the refrigerant in the refrigerant flow path are omitted.

[0016] As shown in Figure 1, the fuel cell stack 10 of this embodiment consists of multiple single cells 1, each composed of a single fuel cell, stacked in the stacking direction. As will be described later, the fuel cell stack 10 is grouped into multiple sections composed of one or more of these single cells 1 for state management.

[0017] A single cell 1 constituting such a fuel cell stack 10 can be exemplified by, for example, a known polymer electrolyte fuel cell (PEFC). Although the fuel cell stack 10 in this embodiment is a polymer electrolyte fuel cell, other known fuel cells such as solid oxide fuel cells may also be used. In each single cell 1 constituting the fuel cell stack 10, a flow path for the fuel gas described above is formed on the anode side, which is one side of the electrolyte membrane, and a flow path for the oxidizing gas (air) is formed on the cathode side, which is the other side of the electrolyte membrane.

[0018] Each single cell 1 constituting the fuel cell stack 10 needs to be supplied with the fuel gas and oxidizing gas mentioned above, as well as a refrigerant (cooling water) necessary for cooling. Therefore, the fuel cell stack 10 of this embodiment is provided with a manifold for distributing or recovering the fluids (fuel gas, oxidizing gas, and cooling water).

[0019] More specifically, as illustrated in Figure 2, the fuel cell stack 10 of this embodiment includes a pair of end plates 2 (first end plate 2A, second end plate 2B) arranged on both ends of the stacked single cells 1 in the stacking direction, a first manifold 3 arranged around the stacked single cells 1 with a flow path formed therein through which the cooling water can flow, and a second manifold 4 arranged around the other end of the stacked single cells 1 with a flow path formed therein through which the fuel gas and oxidizing gas can flow. Of these, the pair of end plates 2 are configured to pressurize the single cells 1 via known fastening studs 11.

[0020] As illustrated in Figure 4, the second manifold 4 of this embodiment is also characterized in that the flow paths for the oxidizing gas and fuel gas are divided for each group (hereinafter also referred to as a "section") composed of one or more single cells 1. Furthermore, as can be seen from the same figure, the air intake pipe 55 is branched so that the oxidizing gas flows to each of the above-mentioned groups. Flow control valves V3 are provided on the air intake pipe 55 that branches off and goes to each group.

[0021] The branched air intake pipes 55 are connected to the inlet-side second manifold 4B, each with its flow path divided into groups. The oxidizing gas supplied to the inlet-side second manifold 4B is then supplied to the cathode side of the single cell 1 within each group, and similarly flows out to the outlet-side second manifold 4A, which is also divided into groups, before being merged.

[0022] Accordingly, the control device 20 of this embodiment can adjust the flow rate of the oxidizing gas supplied to each group by adjusting the opening degree of the flow rate adjustment valve V3 described above. In this way, the flow rate adjustment valve V3 of this embodiment functions as a flow rate adjustment mechanism 30 (see Figure 1) that adjusts the flow rate of the fluid flowing through each of the aforementioned groups or sections. The flow rate adjustment mechanism 30 is not limited to known valve mechanisms such as the flow rate adjustment valve V3 described above, but various known flow rate adjustment means such as a shutter mechanism that can open and close the flow path with a shutter may also be applied. Furthermore, although this embodiment illustrates a configuration in which the flow control valve V3 is installed on the air intake pipe 55, which is the inlet side of each manifold, the embodiment is not limited to this configuration, and the flow control valve V3 may also be installed on the air exhaust pipe 56, which is the outlet side of each manifold. By installing the flow control valve V3 downstream (on the outlet side of each manifold), it can also function as a back pressure valve, making it possible to adjust the pressure in addition to adjusting the flow rate in the relevant section.

[0023] Figure 4 shows an example of adjusting the flow rate of oxidizing gas supplied to each group by adjusting the opening of the flow control valve V3 described above, but the flow rate of fuel gas supplied to each group may be adjusted in the same way. In addition, the flow paths of the first manifold 3 (first manifold 3A and second manifold 3B), which have a cooling water inlet 59 and a cooling water outlet 60 through which cooling water flows, may also be divided into separate flow paths for each group, and the flow rate of cooling water supplied to each group may also be adjusted in the same way. As for the method of manufacturing the manifold, one can refer to, for example, the manufacturing examples of "external manifolds" exemplified in Japanese Patent Publication No. 2010-123325 and Japanese Patent Publication No. 2008-41475.

[0024] The fuel cell stack 10 described above has its state, such as power generation status, managed by a known CMU 20B. This CMU 20B is included in the control device 20 in this embodiment and is a circuit that has the function of detecting the output voltage and output current of each single cell 1 that makes up the fuel cell stack 10. In other words, the CMU 20B as the control device 20 is capable of detecting the output voltage and output current of multiple single cells 1 that are divided into the above-described groups. The voltage and current values ​​for each group detected by this CMU 20B may be output to, for example, the ECU 20A.

[0025] The control device 20 (ECU20A or CMU20B) of this embodiment is configured to include, for example, one or more known memories and one or more CPUs electrically connected to these memories and performing calculations according to a predetermined control program. The control device 20 may also have a known ROM in which control programs and control data necessary for the CPU to perform various calculations are stored in advance, and a known RAM in which various data necessary for the CPU to perform various calculations are temporarily read and written. The control device 20 of this embodiment may perform power generation control by the fuel cell stack 10, drive control of the gas supply system 50, or power supply control to a known load 58 such as an electric motor via a DC / DC converter 57.

[0026] Next, with reference to Figure 3, the configuration of the control device 20 in the fuel cell system 100 of this embodiment will be described. As shown in Figure 2, the control device 20 of this embodiment is composed of a measurement state determination unit 21, a cell state detection unit 22, an environmental information detection unit 23, a grouping adjustment unit 24, and a flow rate adjustment unit 25, among others.

[0027] Such a control device 20 is configured to have the function of managing the state of individual cells 1 that make up the fuel cell stack 10 for each of the multiple sections. The control device 20 can finely manage and optimize the internal state of the fuel cell by partially grouping the number of sections into smaller groups, for example, using the grouping adjustment unit 24, thereby suppressing partial performance degradation and deterioration in the fuel cell stack 10.

[0028] The control device 20 varies the number of the above-mentioned sections according to the environmental information and internal state of the cell, as described later. This allows for fine-grained control of parts that have a significant impact on performance degradation, while relatively coarser control of parts that have a smaller impact. This improves the control accuracy of the fuel cell stack 10 and reduces the computational load required for analyzing the fuel cell stack.

[0029] The measurement state determination unit 21 has the function of determining how many sections in the fuel cell stack 10 described above will be measured. More specifically, as can be understood from Figures 4 and 6, the measurement state determination unit 21 can group the sections such that the number of cells in a first section (e.g., section SC1) and the number of cells in a second section (e.g., section SCk) which is different from this first section are different from each other. For example, in the example shown in Figure 6, section SC1 has 10 cells, while section SCk has 15 cells.

[0030] In the example shown in Figure 6, the fuel cell stack 10 is divided into n sections, numbered No. 1 to No. n, starting from the end, with the kth section located near the center. The number of sections dividing the fuel cell stack 10 can be appropriately set according to the number of single cells 1 connected in series. For example, if more than 300 single cells 1 are directly connected to the fuel cell stack 10, it may be divided into 10 to 20 sections.

[0031] The measurement state determination unit 21 may pre-determine operating points of the fuel cell stack 10 where variations in power generation status between sections are likely to occur, and when the fuel cell stack 10 reaches one of these operating points, it may group or regroup the sections. Examples of such operating points of the fuel cell stack 10 include cell voltage, intake air temperature of oxidizing gas, power generated by the fuel cell (such as during idle or high-load operation), and control of each fluid (oxidizing gas, fuel gas, and cooling water) at low flow rates.

[0032] As described above, in this embodiment, the number of single cells may differ in each section. Therefore, the measurement state determination unit 21 determines the impedance measurement frequency, amplitude, analysis formula, equivalent circuit, or measurement conditions according to known methods, in accordance with the measurement state of each section of the fuel cell stack 10 determined above. At this time, the frequency and amplitude of the AC waveform (e.g., current) applied to the fuel cell stack 10 to calculate the impedance can be basically the same waveform and amplitude applied between each section. On the other hand, for example, when applying a composite waveform containing multiple frequencies to the fuel cell stack 10 to identify the desired power generation state, it is necessary to perform FFT analysis on each section after measurement to separate the frequencies. Therefore, the frequency and amplitude of the AC waveform applied to the fuel cell stack 10 may vary from section to section. Furthermore, the sampling frequency during measurement may also be changed depending on the AC waveform applied to the fuel cell stack 10. For example, the computational load can be reduced by applying a relatively high sampling rate when the applied AC waveform is high frequency, and a relatively low sampling rate when the applied AC waveform is low frequency.

[0033] The cell state detection unit 22 has the function of receiving measurement information from sensors 40 and measuring the state of each section constituting the fuel cell stack 10. Examples of such sensors 40 include, as shown in Figures 1 and 3, a known voltage sensor 41 capable of measuring the voltage value of each section, a known current sensor 42 capable of measuring the current value flowing through the fuel cell stack 10, and a known battery temperature sensor 43 capable of measuring the temperature of the fuel cell stack 10. Although Figure 3 shows three sensors, the sensors 40 may include various known sensors mounted on a vehicle, such as a vehicle speed sensor or a GPS sensor.

[0034] The environmental information detection unit 23 has the function of acquiring environmental information around the FCV, such as temperature and humidity around the fuel cell stack 10, based on known measurement sensors mounted on the FCV. Specific examples of such measurement sensors include, for example, a known ambient temperature sensor that measures the temperature around the FCV, and a known humidity sensor that measures the humidity around the FCV, both of which are known on-board sensors mounted on an FCV.

[0035] The grouping adjustment unit 24 has the function of grouping the fuel cell stack 10, which is made up of multiple single cells 1 stacked on top of each other, into multiple sections. More specifically, the grouping adjustment unit 24 may group the multiple sections such that the number of cells in the first section and the number of cells in a second section different from the first section are different from each other.

[0036] Furthermore, as will be described later, the grouping adjustment unit 24 may group the cells such that the number of cells constituting the section located on the central side of the fuel cell stack 10 (for example, section SCk in Figure 6) is different from the number of cells constituting the sections located on the ends of the fuel cell stack (SC1 and SCn in Figure 6). In this case, it is preferable that the grouping adjustment unit 24 group the cells such that the number of cells constituting the sections on the ends of the fuel cell stack is smaller than the number of cells constituting the sections located on the central side of the fuel cell stack.

[0037] The flow rate adjustment unit 25 has the function of adjusting the flow rate of the fluid (in this example, oxidizing gas, but it may also be fuel gas or cooling water) flowing through each section adjusted by the grouping adjustment unit 24. More specifically, the flow rate adjustment unit 25 can adjust the flow rate of the fluid flowing through each of the multiple sections in the fuel cell stack 10 via the flow rate adjustment mechanism 30 described above.

[0038] <Method for managing the status of fuel cell systems> Next, with reference to Figure 5 as appropriate, the method for managing the state of the fuel cell system 100 in this embodiment will be described. As shown in Figure 5, in step 1, the measurement state determination unit 21 of the control device 20 first determines how many sections in the fuel cell stack 10 described above will be measured. In this embodiment, as shown in Figure 4, five stacked single cells 1 are considered as one section. Therefore, the control device 20 can manage the state of each of the five single cells 1 as one section.

[0039] In such a fuel cell stack 10, the measurement state determination unit 21 groups the cells such that the number of cells constituting section SCk, located on the central side of the fuel cell stack 10 (15 in this example), and the number of cells constituting sections located on the ends of the central side (section SC1 and section SCn) (10 in this example) are different from each other, as shown in Figure 6. For the sake of explanation, the air exhaust pipe 56 and cooling water flow path connected to the fuel cell stack 10 are omitted from the illustration in Figure 6.

[0040] Next, in step 2, the measurement state determination unit 21 of the control device 20 determines the measurement frequency, amplitude, analysis formula, equivalent circuit, or measurement conditions for each section of the impedance according to a known method, in accordance with the measurement state for each section of the fuel cell stack 10 determined above. In other words, the measurement frequency, amplitude, and analysis formula for the impedance in the end sections (section SC1 and section SCn) are subject to different conditions than those for the impedance in section SCk, which is located in the center.

[0041] Next, in step 3, the cell state detection unit 22 receives measurement information from sensors 40 such as the voltage sensor 41 and measures the cell state, including the impedance of each section constituting the fuel cell stack 10.

[0042] Next, in step 4, the cell state detection unit 22 determines whether the variation in resistance in each section is within a specified range, based on the impedance in each section detected in step 3. The method for measuring the impedance in each section is not particularly limited and may be calculated using known AC impedance methods, such as those described in Japanese Patent Application Publication No. 2017-201627 or Japanese Patent Application Publication No. 2020-198208. Furthermore, regarding "resistance variation," the appropriate range for the specifications of the single cell used can be determined in advance through experimentation or simulation, and this appropriate range can be set as the specified range mentioned above.

[0043] Then, in step 4, if the resistance variation in each section is within the specified range (Yes in step 4), in step 6, it is determined whether or not the FCV system has been shut down. If the vehicle's system is still running, the process returns to step 3 and continues as described above. On the other hand, if the variation in resistance in each section in step 4 is not within the specified range (No in step 4), then the sections are regrouped in step 5.

[0044] In other words, in step 5, the environmental information detection unit 23 first acquires environmental information around the FCV, such as temperature and humidity around the fuel cell stack 10, based on known measurement sensors (sensors 40) mounted on the FCV.

[0045] Then, in step 5, the grouping adjustment unit 24 adjusts the section SC located at the end of the fuel cell stack 10 based on environmental information acquired by, for example, the environmental information detection unit 23. ed The cells are regrouped so that they make up an even smaller number of cells. In other words, as can be seen by comparing Figures 6 and 7, Section SC1, which originally consisted of 10 single cells, is divided into Section SC1 and Section SC2 after regrouping, each consisting of 5 single cells.

[0046] Note that the detection of environmental information by the environmental information detection unit 23 is not necessarily required for grouping or regrouping and may be omitted as appropriate. In this case, the grouping or regrouping described above may be performed by referring to regions with large temperature changes that have been previously identified through experiments or simulations.

[0047] This allows for more fine-grained grouping of parts of the fuel cell stack 10 that experience large temperature fluctuations, such as the end sections, thereby enabling more optimal state management compared to before regrouping. Thus, the fuel cell system 100 of this embodiment further includes a measurement sensor that measures at least one of the surrounding environment and internal state of the fuel cell stack 10, and the control device 20 may have a function to reorganize the grouping of multiple sections so that the number of cells in the first section and the number of cells in the second section are different, based on the measurement results of this measurement sensor.

[0048] In step 5, the flow rate adjustment unit 25 adjusts the flow rate of the fluid flowing through each section adjusted by the grouping adjustment unit 24, based on the regrouped state. As an example, as shown in Figure 8, the flow rate adjustment unit 25 adjusts the flow rate of the fluid via the flow rate adjustment mechanism 30 so that each single cell 1 is in an optimal state based on the state of the single cell 1 in each section.

[0049] For example, if it is found that a single cell 1 in a certain section (e.g., section SC1) is in a dry state, the flow rate adjustment unit 25 may, via the flow rate adjustment mechanism 30, reduce the flow rate of the oxidizing gas or increase the flow rate of the cooling water only in section SC1. In this case, since section SC1 has been made wet, it can be assumed that other sections (e.g., the adjacent section SC2) will also be affected. Therefore, if the flow rate adjustment unit 25 finds that a single cell 1 in another section is prone to flooding in conjunction with the flow rate adjustment in one section as described above, the flow rate adjustment unit 25 may, for example, reduce the flow rate of the cooling water in that section only via the flow rate adjustment mechanism 30.

[0050] Thus, the flow rate adjustment unit 25 of this embodiment may have the function of adjusting the flow rate of the other second section (section SC2 in the above example) among the multiple sections in accordance with the flow rate adjustment of the first section (section SC1 in the above example) via the flow rate adjustment mechanism 30.

[0051] <Second Embodiment> Next, the fuel cell system 110 of the second embodiment will be described with reference to Figure 9. In the fuel cell system 100 of the first embodiment described above, one section was composed of at least five single cells 1.

[0052] In contrast, the fuel cell system 110 in this embodiment is characterized by the fact that the state of each individual cell 1 constituting the fuel cell stack 10, such as voltage and current, can be measured, and the flow rate of the fluid (oxidizing gas, fuel gas, and cooling water) flowing to each cell 1 can be adjusted individually. In the following explanation, configurations having the same functionality as those previously described will be given the same reference numbers, and their explanations will be omitted as appropriate.

[0053] As shown in Figure 9, in the fuel cell system 110 of the second embodiment, a voltage sensor 41 is provided individually for each single cell 1 that constitutes the fuel cell stack 10, making it possible to detect the voltage of each individual single cell 1. Furthermore, in the fuel cell system 110 of the second embodiment, the flow paths formed in the first manifold 3 and the second manifold 4 are divided for each single cell 1, and the flow rate adjustment mechanism 30 is capable of individually adjusting the fluid flow rate for each single cell 1.

[0054] Furthermore, in the fuel cell system 110 of the second embodiment, the control device 20 can configure sections with any number of single cells 1 in the fuel cell stack 10 which is composed of multiple single cells 1. For example, the control device 20 may configure section SC1 located at the end of the fuel cell stack 10 to have 3 cells, while section SCk located in the center to have 6 cells. In this case, the control device 20 can synchronize the opening and closing of multiple flow control valves V3 belonging to the same section according to each section.

[0055] In this way, the control device 20 of the fuel cell system 110 can divide the fuel cell stack 10 into any number of sections, and the number of cells constituting each section can also be set to any number. Furthermore, even in the regrouping in step 5 described above, the control device 20 of the fuel cell system 110 can reset the sections and the number of cells that were previously set to any number of sections and cells. This makes it possible to set the optimal section divisions and the number of cells belonging to each section in accordance with changes in the state of the fuel cell stack 10 and environmental information.

[0056] According to the fuel cell system of this disclosure described above, the fuel cell stack, in which multiple single cells are stacked, is not only managed in any number of sections, but the number of cells constituting each section is also varied in a skewed distribution, thereby effectively suppressing performance degradation and deterioration of individual cells.

[0057] The embodiments described above are merely preferred examples of this disclosure, and new structures and controls may be realized by appropriately combining elements of the embodiments without departing from the spirit of this disclosure. The following describes some modifications applicable to these embodiments.

[0058] <Variation> Figure 10 shows a modified example of the above-described embodiment for a fuel cell system. As shown in the figure, a heat source HS is arranged around the fuel cell stack 10. Examples of such heat sources HS include various known heat sources such as the inverter in an FCV and the DC / DC converter described above.

[0059] As shown in the figure, the fuel cell stack 10 of this modified example has a section SChs that is close to the heat source HS and other sections that are not significantly affected by the heat from the heat source HS (for example, section SC located at the end in this example). ed Sections SC1 and SCn, etc., can be classified into these. Therefore, the grouping adjustment unit 24 of the control device 20 is configured to adjust the section SC1 and SCn, which are close to the heat source HS in the fuel cell stack 10, as shown in Figure 10. hs You may group or regroup the cells so that the number of cells making up the group becomes even finer.

[0060] In other words, the grouping adjustment unit 24 of the control device 20 is located in the central section SC, as can be seen from Figure 10. md The number of cells that make up the section (15 in this example) and the section SC located at the end. ed The number of cells constituting the section SC (10 in this example) is greater than the number of cells in the section SC that are adjacent to the heat source HS. hs You may set a smaller number of cells to make up the array (5 in this example).

[0061] Thus, the control device 20 may group the cells in the fuel cell stack 10 so that areas with large temperature fluctuations, such as the ends or near the heat source, are more finely distributed than other areas. Examples of "areas with large temperature fluctuations" include, in addition to the ends and near the heat source, areas near the air intake duct, areas that are easily exposed to moisture such as rainwater, and areas near the compressor.

[0062] Furthermore, when performing the grouping described above, the control device 20 may change the number of cells constituting each section in stages according to the distance from the heat source within the fuel cell stack 10. Specifically, the control device 20 may group the cells by relatively reducing the number of cells constituting each section on the side closer to the heat source and gradually increasing the number of cells constituting each section as the distance from the heat source increases.

[0063] According to the modified fuel cell system described above, the state of individual cells in areas susceptible to the influence of heat sources arranged around the fuel cell system can be precisely controlled, further suppressing performance degradation and deterioration of individual cells.

[0064] Preferred embodiments and modifications of the present disclosure have been described in detail above with reference to the attached drawings, but the present disclosure is not limited to such examples. It is obvious to any person with ordinary skill in the art to which the present disclosure belongs that further modifications to these embodiments and modifications will be attempted within the scope of the technical idea set forth in the claims, and these will naturally also fall within the technical scope of the present disclosure. [Explanation of symbols]

[0065] 10 Fuel Cell Stacks 20 Control device 30 Flow rate adjustment mechanism 40 Sensors 50 Gas supply system 100 Fuel Cell Systems

Claims

1. A fuel cell stack, which is grouped into multiple sections consisting of one or more cells and generates electricity in parallel in the multiple sections, A control device that manages the state of the cells for each of the aforementioned multiple sections, A flow rate adjustment mechanism adjusts the flow rate of the fluid circulating in each of the multiple sections based on the state management by the control device, The system includes a sensor that acquires environmental information around the fuel cell stack, The plurality of sections that generate power in parallel include at least a first section and a second section different from the first section, The control device is The grouping is performed such that the number of cells in the first section and the number of cells in the second section are different from each other, and Based on the acquired environmental information and at least one of the internal state of the cell, the grouped sections are regrouped. Fuel cell system.

2. The control device performs the grouping such that the number of cells constituting the section located on the central side of the fuel cell stack is different from the number of cells constituting the section located on the edge side of the central side. The fuel cell system according to claim 1.

3. The fuel cell stack is grouped such that the number of cells in the section located at the end is smaller than the number of cells in the section located at the center. The fuel cell system according to claim 1.

4. The system further includes a measuring sensor that measures at least one of the surrounding environment and internal state of the fuel cell stack, The control device is Based on the measurement results of the measurement sensor, the grouping of the multiple sections is rearranged so that the number of cells in the first section and the number of cells in the second section are different. The fuel cell system according to claim 1.

5. The aforementioned flow rate adjustment mechanism is When the fluid flow rate in the first section of the plurality of sections is adjusted, the flow rate of the other second sections of the plurality of sections is adjusted in accordance with the flow rate adjustment of the first section. A fuel cell system according to any one of claims 1 to 4.

6. In the regrouping, the section with a larger temperature change than the other sections is grouped more finely. A fuel cell system according to any one of claims 1 to 4.

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