JP2016018627A - Separator, cell stack and fuel battery system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a novel technique that can prevent occurrence of flooding in a solid-state polymer type fuel battery.SOLUTION: A first hydrogen flow path 13 and a second hydrogen flow path 23 whose hydrogen gas flowing directions are opposite to each other are adjacently arranged to be extended side by side, thereby constructing a hydrogen flow path provided to the power generation surface of an anode separator 51. Paying attention to one hydrogen flow path, there is a tendency that the hydrogen concentration is lowered as the hydrogen flow path is farther away from a hydrogen supply port, so that the power generation amount is reduced and the temperature is lowered. Since the flow path directions of the first hydrogen flow path 13 and the second hydrogen flow path 23 are opposite to each other, a portion of one flow path at which the hydrogen concentration is low and the temperature decreases is located in the neighborhood of a portion of the other flow path at which the hydrogen concentration is high and the temperature increases. Thus, a low-temperature part is not generated and condensation of water vapor in the hydrogen flow path is prevented, thereby preventing occurrence of flooding.SELECTED DRAWING: Figure 5

Description

  The present invention relates to a separator for a polymer electrolyte fuel cell.

Conventionally, a polymer electrolyte fuel cell (PEFC) is known (see, for example, Patent Document 1).
As for the polymer electrolyte fuel cell, a phenomenon called “flooding” that degrades the cell performance is known. That is, as shown in FIG. 9, in the separator 90 (hydrogen separator, current collector plate constituting the gas diffusion part on the fuel electrode side, bipolar plate) in the single cell constituting the cell stack of the polymer electrolyte fuel cell, A hydrogen flow path 93 is provided meandering from one edge of the hydrogen inlet 92 to the opposite edge of the unreacted hydrogen outlet 94. In the vicinity of the supply port AH that is upstream of the hydrogen flow path 93, the hydrogen concentration is high and the generated current is large and the temperature is high, but in the vicinity of the discharge port AL that is downstream, the hydrogen concentration is low and the generated current is relatively small. It becomes low temperature. Therefore, water generated by the reaction (ionization reaction on the anode surface) in the vicinity of the supply port AH flows downstream as water vapor, but condensation can occur in the vicinity of the discharge port AL. The state in which this has progressed is flooding, and the flow path is narrowed by condensed water, and in some cases, the flow path is closed. When flooding occurs, the electrode assembly (MEA: Membrane Electrode Assembly) in the cell constituting the cell stack deteriorates due to the oxidative corrosion reaction of the conductive material caused by the accumulated water, and eventually becomes unable to generate power.

  As a countermeasure against flooding, for example, a technique is known in which the voltage of each cell is measured and the supply port and the discharge port of hydrogen are switched to reduce the bias in power generation distribution when the voltage drops below a certain voltage. (For example, see Patent Document 2).

JP 2003-317753 A JP 2006-210118 A

  In the techniques disclosed in Patent Documents 1 and 2, the state where the power generation distribution is biased is reduced as much as possible, and the deterioration of MEA (Membrane Electrode Assembly), which is an assembly of the solid polymer membrane (electrolyte) and the electrode, is suppressed, thereby extending the life. Although it can be extended, it was not possible to fundamentally prevent the uneven distribution of power generation.

  Accordingly, an object of the present invention is to realize a new technique for preventing the occurrence of flooding in a polymer electrolyte fuel cell.

A first invention for solving the above problems is a separator of a polymer electrolyte fuel cell in which a gas flow path for allowing a gas for power generation to flow is formed,
First and second gas inlets (for example, the first hydrogen inlet 12 and the second hydrogen inlet 22 in FIG. 2);
First and second gas discharge portions (for example, the first hydrogen discharge port 14 and the second hydrogen discharge port 24 in FIG. 2);
A first gas flow path (for example, the first hydrogen flow path 13 in FIG. 2) from the first gas inflow section to the first gas discharge section;
A second gas flow path (for example, the second hydrogen flow path 23 in FIG. 2) from the second gas inflow portion to the second gas discharge portion;
The first gas flow path and the second gas flow path are separators configured such that the flow directions run side by side in an opposing relationship.

  According to a second aspect of the present invention, the first gas inflow portion and the second gas discharge portion are provided at one edge portion of the separator, and the first gas discharge portion and the second gas inflow portion are The separator according to the first aspect of the invention, which is provided at the other edge portion of the separator, and is configured such that the first gas channel and the second gas channel meander in parallel.

  The third invention is a cell stack in which one cell is formed by pairing the oxygen separator as the separator of the second invention and the hydrogen separator as the separator of the second invention.

  According to any one of the first to third inventions, the first gas flow path and the second gas flow path run in opposite directions in the direction of flow of the power generation gas. The high temperature part which concerns on the other gas flow path exists in the vicinity of the low temperature part which concerns. Therefore, it is difficult to generate a low-temperature portion in which water vapor is condensed, and a structure that can prevent flooding is obtained.

As a fourth invention,
The cell stack according to the third aspect of the present invention may be configured in which the direction of the parallel meandering of the oxygen separator and the direction of the parallel meandering of the hydrogen separator are different.

The fifth invention is the cell stack of the third or fourth invention,
A first reaction measurement unit (for example, the first reaction sensor 51 in FIG. 6) that measures the degree of fuel reaction in the first region of the cell stack on the one edge side;
A second reaction measurement unit (for example, the second reaction sensor 52 in FIG. 6) that measures the degree of fuel reaction in the second region of the cell stack on the other edge side;
A first flow rate adjusting unit (for example, the first electric pump 132 in FIG. 6) that adjusts the flow rate to the first gas inflow unit;
A second flow rate adjusting unit (for example, the second electric pump 134 in FIG. 6) that adjusts the flow rate to the second gas inflow unit;
Based on the measurement results of the first and second reaction measurement units, a control unit (for example, the computer 64 in FIG. 6) that controls the first and second flow rate adjustment units;
Is a fuel cell system.

  According to the fifth aspect of the present invention, it is possible to further adjust the flow rate for each gas flow path to adjust the power generation amount, that is, the heat generation amount, for each region of the first region and the second region. Even if there is a difference in the degree of reaction between the first region and the second region for some reason, it can be corrected to prevent the occurrence of a low-temperature location that causes condensation.

  According to a sixth aspect of the present invention, the gas is introduced in parallel from the predetermined gas supply source to the first gas inflow portion and the second gas inflow portion, and the first gas flow path and the second gas flow path are It is the fuel cell system of 5th invention comprised as a parallel flow path of gas.

  According to the sixth aspect, since the gas from the gas supply source can be supplied to the first gas channel and the second gas channel in the same manner, a reaction difference between the gas channels, that is, a heat generation difference can be hardly generated.

  Of course, as a seventh invention, the first gas discharge part and the second gas inflow part are connected via a predetermined gas flow path, and the gas is supplied from a predetermined gas supply source to the first gas inflow part. A fuel cell system according to a fifth aspect of the present invention (for example, the fuel cell system 100C in FIG. 7) is configured in which the first gas flow path and the second gas flow path are configured as a serial flow path of the gas. It is also possible.

The structural example of a polymer electrolyte fuel cell (1) Side view, (2) Top view. The figure which shows the structural example by the side of the electric power generation surface (facing contact surface with MEA) of an anode separator. The figure which shows the structural example by the side of the electric power generation surface (facing contact surface with MEA) of a cathode separator. The figure which shows an example of the system configuration | structure which concerns on the fuel system of the fuel cell system of 1st Embodiment, and a control system. The figure for demonstrating the effect of 1st Embodiment. The figure which shows an example of the system configuration | structure which concerns on the fuel system of the fuel cell system of 2nd Embodiment, and a control system. The figure which shows an example of the system configuration | structure which concerns on the fuel system in the modification of a fuel cell system, and a control system. The figure which shows the modification of a structure of a cathode separator. The figure which shows the structural example of the conventional anode separator.

[First Embodiment]
FIG. 1 is a (1) side view and (2) top view showing a configuration example of a solid polymer fuel cell in the first embodiment.
A cell stack 2 of a polymer electrolyte fuel cell is a type of fuel cell that uses a polymer ion exchange membrane as an electrolyte and uses hydrogen gas as a fuel for power generation. The negative electrode 6 and the positive electrode 7 are sandwiched, and both ends thereof are sandwiched between the insulating plate 8 and the end plates 9m and 9p, and are integrally connected.

  The end plate 9m on the negative electrode side is provided with a first hydrogen supply port 11, a second hydrogen discharge port 25, a first oxygen supply port 31, and a second oxygen discharge port 45. The end plate 9p on the positive electrode side is provided with a first hydrogen discharge port 15, a second hydrogen supply port 21, a first oxygen discharge port 35, and a second oxygen supply port 41.

  In the cell stack 2, a system that extends from the first hydrogen supply port 11 to each single cell 5 and reaches the first hydrogen discharge port 15, and a second hydrogen that travels from the second hydrogen supply port 21 to each single cell 5. Two systems of hydrogen gas flow paths with the system reaching the discharge port 25 are provided. Similarly, a system extending from the first oxygen supply port 31 to each of the single cells 5 to the first oxygen discharge port 35 and a second oxygen supply port 41 to each of the single cells 5 to the second oxygen discharge port 45. Two channels of oxygen gas (or air) with the system are provided.

  The single cell 5 is a unit in which an anode separator 51 (hydrogen separator), an MEA 52, and a cathode separator 53 (oxygen separator) are laminated and integrated as in the known PEFC. Heat radiation fins are also provided on the outside of each.

FIG. 2 is a diagram illustrating a configuration example of the anode separator 51 of the present embodiment on the power generation surface (facing contact surface with the MEA) side.
In the left edge portion (upper side in FIG. 2) of the anode separator 51 of the present embodiment, a first hydrogen inlet 12 connected to the first hydrogen supply port 11 and a second hydrogen outlet 24 connected to the second hydrogen discharge port 25. And a first oxygen inlet 32 connected from the first oxygen supply port 31 and a second oxygen outlet 44 connected to the second oxygen discharge port 45 are provided.
On the opposite right edge (lower side in FIG. 2), a first hydrogen discharge port 14 connected to the first hydrogen discharge port 15, a second hydrogen inlet 22 connected from the second hydrogen supply port 21, and a first A first oxygen discharge port 34 connected to the oxygen discharge port 35 and a second oxygen inflow port 42 connected from the second oxygen supply port 41 are provided.

  A groove connecting the first hydrogen inlet 12 and the first hydrogen outlet 14 is provided on the power generation surface of the anode separator 51 while meandering in the vertical direction (left-right direction in FIG. 2) so as to cover the power generation surface. ing. This is referred to as a first hydrogen channel 13. Similarly, a groove connecting the second hydrogen inlet 22 and the second hydrogen outlet 24 is provided while meandering in the vertical direction so as to cover the power generation surface. This is referred to as a second hydrogen channel 23. The first hydrogen channel 13 and the second hydrogen channel 23 are provided so as to be adjacent to each other and run side by side. However, when attention is paid to the hydrogen flow, the flow directions are opposite to each other.

  The groove cross-sectional shapes of the first hydrogen channel 13 and the second hydrogen channel 23 are set so that the same pressure loss is generated when the hydrogen supply pressure is the same, that is, the same flow rate flows. In the present embodiment, the entire passage is substantially the same, but depending on the layout design of the passage, there may be a difference in groove cross-sectional shape and cross-sectional area depending on the location.

  Since the MEA 52 can be realized in the same manner as a known technique, the description thereof is omitted.

FIG. 3 is a diagram illustrating a configuration example of the cathode separator 53 of the present embodiment on the power generation surface (facing contact surface with the MEA) side.
A first hydrogen inlet 12, a second hydrogen outlet 24, a first oxygen inlet 32, and a second oxygen outlet 44 are provided on the left edge of the cathode separator 53 (upper side in FIG. 3). ing. In addition, a first hydrogen discharge port 14, a second hydrogen inlet 22, a first oxygen outlet 34, and a second oxygen inlet 42 are provided on the right edge (lower side in FIG. 3). Yes.

  A first oxygen flow path 33 meanders from the first oxygen inlet 32 toward the first oxygen outlet 34 on the power generation surface of the cathode separator 53. A second oxygen channel 43 is provided from the second oxygen inlet 42 toward the second oxygen outlet 44.

  The first oxygen channel 33 and the second oxygen channel 43 are provided so as to be adjacent to each other and run side by side. However, when attention is paid to the flow of oxygen, the flow directions are opposite to each other. In addition, the first hydrogen flow path 13 and the second hydrogen flow path 23 shown in FIG. 2 are generally left and right flow paths while meandering in the vertical direction (left and right direction in FIG. 2). The first oxygen channel 33 and the second oxygen channel 43 shown in FIG. 3 are generally vertical channels while meandering in the left-right direction (vertical direction in FIG. 3). Channels are formed so as to intersect.

  The groove cross-sectional shapes of the first oxygen channel 33 and the second oxygen channel 43 are set so as to produce the same pressure loss if the oxygen supply pressure is the same, that is, the same flow rate flows. In the present embodiment, the entire passage is substantially the same, but depending on the layout design of the passage, there may be a difference in groove cross-sectional shape and cross-sectional area depending on the location.

  FIG. 4 is a diagram showing a system configuration related to the fuel system and the control system of the fuel cell system 100 of the present embodiment. In addition, since a well-known structure is applicable about other system components, such as an oxygen system, a cooling system, and a humidification system, illustration and description here are abbreviate | omitted.

  The fuel cell system 100 adjusts the hydrogen gas provided from the hydrogen supply source 140 to a predetermined atmospheric pressure by the regulator 142 and supplies the hydrogen gas to the first hydrogen supply pipe 110 and the second hydrogen supply pipe 120 in parallel. The first hydrogen supply pipe 110 is connected to the first hydrogen supply port 11 of the cell stack 2, and the second hydrogen supply pipe 120 is connected to the second hydrogen supply port 21. Thereby, the 1st hydrogen channel 13 and the 2nd hydrogen channel 23 are constituted as a parallel channel.

  A first hydrogen recovery pipe 116 is connected to the first hydrogen discharge port 15 of the cell stack 2, and a second hydrogen recovery pipe 126 is connected to the second hydrogen discharge port 25. Both recovery pipes are guided to the gas-liquid separator 130.

The gas-liquid separator 130 is realized by a known gas-liquid separator or an aggregating device.
An electric pump 132 is connected to the gas-liquid separator 130, and the electric pump 132 sucks out the unreacted hydrogen gas from which the liquid has been separated from the gas-liquid separator 130, and the first return pipe 117 and the second return pipe 127. Through the first hydrogen supply pipe 110 and the second hydrogen supply pipe 120, respectively, at a pressure equal to or lower than the adjustment pressure of the regulator 142.

FIG. 5 is a diagram for explaining the function and effect of the present embodiment.
Paying attention to the concentration of hydrogen flowing through the first hydrogen channel 13 and the second hydrogen channel 23, the hydrogen concentration becomes closer to the supply port (first hydrogen inlet 12, second hydrogen inlet 22) in any of the passages. Is high, and the concentration decreases as it approaches the discharge ports (first hydrogen discharge port 14, second hydrogen discharge port 24). Therefore, in both the first hydrogen flow path 13 and the second hydrogen flow path 23, the reaction near the supply port becomes higher as the position is closer to the supply port, and a larger amount of current flows to increase the heat generation amount. On the contrary, as it approaches the discharge port, the reaction is reduced, the flowing current is reduced, and the heat generation amount is reduced.

  Accordingly, suppose that both the first hydrogen inlet 12 and the second hydrogen inlet 22 are on the same side edge, and both the first hydrogen outlet 14 and the second hydrogen outlet 24 are opposite to each other. (Ie, the hydrogen flow direction of the first hydrogen flow path 13 and the second hydrogen flow path 23 are the same), the supply port side becomes hot as in the case of the conventional anode separator. Flooding may occur due to low temperatures on the exit side.

  However, in the present embodiment, since the first hydrogen inlet 12 and the second hydrogen inlet 22 are located at the opposite edge portions, the first hydrogen passage 13 and the second hydrogen passage 23 have hydrogen gas. The flow direction is in the opposite direction. Then, the flow paths are arranged adjacent to each other and further bent and meandered so that hydrogen gas can be distributed all over the power generation surface.

  As a result, a range where the heat generation amount of the first hydrogen flow path 13 is high is adjacent to a range where the heat generation amount of the second hydrogen flow path 23 is low, and a range where the heat generation amount of the first hydrogen flow path 13 is low is the second range. The portion of the hydrogen flow path 23 where the heat generation amount is high is adjacent. The same is true for the cathode separator 53. Therefore, when viewed on the entire power generation surface of the anode separator 51 and the cathode separator 53, the power generation distribution by the electrochemical reaction can be homogenized. Therefore, a low temperature portion where water vapor is condensed cannot be formed, and flooding can be prevented.

[Second Embodiment]
Next, a second embodiment to which the present invention is applied will be described. In the following, only differences from the first embodiment will be described, and the same components are assigned the same reference numerals and redundant description will be omitted.

FIG. 6 is a diagram illustrating a configuration example of the fuel cell system 100B in the present embodiment, and is a diagram illustrating a system configuration related to a fuel system and a control system.
In the fuel cell system 100B, in addition to the configuration of the first embodiment, the second gas-liquid separator 133 and the second electric pump 134 are independently provided between the second hydrogen recovery pipe 126 and the second return pipe 127. Is provided. The configuration in which the first hydrogen channel 13 and the second hydrogen channel 23 are configured as a hydrogen parallel channel is the same as that of the first embodiment.

Further, in the cell stack 2, the first reaction for measuring the reaction degree (power generation degree) in each of the left half first area and the right half second area of the anode separator 51 (see FIG. 5). A sensor 61 and a second reaction sensor 62 are provided.
For the first reaction sensor 61 and the second reaction sensor 62, for example, a magnetic sensor for detecting a magnetic change caused by the generated current, a temperature sensor for knowing the amount of generated heat, and the like are attached to the back surface of the power generation surface of the anode separator 51. It is realized by.
The output signals from these sensors are converted into digital signals via the input interface device 63 corresponding to the type of sensor and input to the computer 64.

  The computer 64 executes a predetermined program so that a difference in power generation distribution between the first region and the second region does not occur based on the input measurement results by the first reaction sensor 61 and the second reaction sensor 62. The first electric pump 132 and the second electric pump 134 are driven and controlled. This prevents flooding.

  Specifically, the difference in power generation distribution between the first region and the second region is determined from the difference between the measured values of the first reaction sensor 61 and the second reaction sensor 62. If the measured value of the first reaction sensor 61 exceeds the measured value of the second reaction sensor 62 by a given reference value or more, it is determined that the power generation amount in the second region has decreased, and the second A control signal for increasing the driving force of the electric pump 134 is output via the output interface device 65. That is, control is performed to increase the power generation amount by increasing the flow rate to the second hydrogen flow path 23.

  On the other hand, when the measured value of the second reaction sensor 62 exceeds the measured value of the first reaction sensor 61 by a given reference value or more, it is determined that the power generation amount in the first region is decreased, A control signal for increasing the driving force of one electric pump 132 is output via the output interface device 65. That is, the power generation amount is increased by increasing the flow rate to the first hydrogen flow path 13.

  According to the present embodiment, flooding can be basically suppressed as in the first embodiment. Furthermore, even if there is a difference in pressure loss between the first hydrogen passage 13 and the second hydrogen passage 23 and a difference in power generation amount, this can be corrected and prevented before flooding occurs. it can.

[Modification]
As mentioned above, although embodiment which applied this invention was described, embodiment of this invention is not limited to these, The addition, omission, and change of a component can be performed suitably.

  For example, in the above embodiment, only one set of the first hydrogen channel 13 and the second hydrogen channel 23 is provided in one anode separator 51, but a configuration in which a plurality of sets are provided is also possible. The same can be said for the set of the first oxygen channel 33 and the second oxygen channel 43 of the cathode separator 53.

  The anode separator 51 has a hydrogen supply port (first hydrogen inlet 12 and second hydrogen inlet 22) and a discharge port (first hydrogen discharge port 14 and second hydrogen discharge port 24). It is provided with a positional relationship of 180 ° across the center. However, if the hydrogen flow directions of the first hydrogen channel 13 and the second hydrogen channel 23 are opposite, the positional relationship is set to 90 ° or 270 °. It is also possible to do. The same applies to the first oxygen channel 33 and the second oxygen channel 43 of the cathode separator 53.

  Further, as shown in the fuel cell system 100C of FIG. 7, unreacted hydrogen discharged from the first hydrogen channel 13 (the channel from the first hydrogen inlet 12 to the first hydrogen outlet 14) is removed by gas. The liquid was supplied to the second hydrogen passage 23 (the passage from the second hydrogen inlet 22 to the second hydrogen outlet 24) via the liquid separator 130 and the electric pump 132, and was discharged from the second hydrogen passage 23. It is good also as a structure which returns unreacted hydrogen to the 1st hydrogen supply piping 110. FIG. In other words, the first hydrogen channel 13 and the second hydrogen channel 23 may be configured as a series channel.

  Further, as shown in FIG. 8, the oxygen channel of the cathode separator 53 is left as one of the first oxygen channel 33 and the second oxygen channel 43 (the first oxygen channel 33 in the example of FIG. 8). The other can be omitted.

  Further, pure oxygen gas may be flowed through the oxygen system, or air may be flowed. The same configuration as that of FIG. 4, FIG. 6, or FIG. 7 can be applied to the oxygen system. In the case of flowing the atmosphere through the oxygen system, a pump that sucks the atmosphere may be used instead of the gas supply source (hydrogen supply source 140 in the example of FIG. 4).

2 ... cell stack 5 ... single cell 6 ... negative electrode 7 ... positive electrode 8 ... insulating plate 9m ... end plate 9p ... end plate 11 ... first hydrogen supply port 12 ... first hydrogen inlet 13 ... first hydrogen flow path 14 ... 1st hydrogen discharge port 15 ... 1st hydrogen discharge port 21 ... 2nd hydrogen supply port 22 ... 2nd hydrogen inflow port 23 ... 2nd hydrogen flow path 24 ... 2nd hydrogen discharge port 25 ... 2nd hydrogen discharge port 31 ... 1st oxygen supply port 32 ... 1st oxygen inflow port 33 ... 1st oxygen flow path 34 ... 1st oxygen discharge channel 35 ... 1st oxygen discharge port 41 ... 2nd oxygen supply port 42 ... 2nd oxygen inflow port 43 ... 1st 2 Oxygen flow path 44 ... 2nd oxygen exhaust path 45 ... 2nd oxygen exhaust port 51 ... Anode separator 52 ... MEA
53 ... Cathode separator 61 ... First reaction sensor 62 ... Second reaction sensor 63 ... Input interface device 64 ... Computer 65 ... Output interface device 100, 100B, 100C ... Fuel cell system 110 ... First hydrogen supply piping 116 ... First hydrogen Recovery pipe 117 ... first return pipe 120 ... second hydrogen supply pipe 126 ... second hydrogen recovery pipe 127 ... second return pipe 130 ... gas-liquid separator 132 ... electric pump, first electric pump 133 ... second gas Liquid separator 134 ... second electric pump 140 ... hydrogen supply source 142 ... regulator

Claims (7)

A separator of a polymer electrolyte fuel cell in which a gas flow path for allowing a gas for power generation to flow is formed,
First and second gas inflow portions;
First and second gas discharge parts;
A first gas flow path from the first gas inlet to the first gas outlet;
A second gas flow path from the second gas inlet to the second gas outlet;
The separator is configured such that the first gas channel and the second gas channel run side by side in a facing relationship. The first gas inflow portion and the second gas discharge portion are provided at one edge portion of the separator,
The first gas discharge part and the second gas inflow part are provided on the other edge part of the separator,
The first gas flow path and the second gas flow path are configured to meander in parallel,
The separator according to claim 1.   A cell stack in which one cell is formed by pairing the separator for oxygen which is the separator according to claim 2 and the separator for hydrogen which is the separator according to claim 2. The direction of the parallel meandering of the oxygen separator and the direction of the parallel meandering of the hydrogen separator are configured in different directions.
The cell stack according to claim 3. The cell stack according to claim 3 or 4,
A first reaction measurement unit for measuring a fuel reaction degree in a first region of the cell stack on the one edge side;
A second reaction measuring unit that measures the degree of fuel reaction in the second region of the cell stack on the other edge side;
A first flow rate adjusting unit for adjusting a flow rate to the first gas inflow portion;
A second flow rate adjustment unit for adjusting a flow rate to the second gas inflow portion;
A control unit for controlling the first and second flow rate adjustment units based on the measurement results of the first and second reaction measurement units;
A fuel cell system comprising:   The gas flows in parallel from the predetermined gas supply source to the first gas inflow portion and the second gas inflow portion, and the first gas flow path and the second gas flow path serve as the parallel flow paths of the gas. The fuel cell system according to claim 5 configured.   The first gas discharge part and the second gas inflow part are connected via a predetermined gas flow path, and the gas flows into the first gas inflow part from a predetermined gas supply source, and the first gas flow The fuel cell system according to claim 5, wherein a path and the second gas flow path are configured as a serial flow path of the gas.

Images