JP2008130228A - Fuel cell stack and manufacturing method thereof - Google Patents

Abstract

The present invention provides a technique for improving non-uniformity in power generation performance for each single cell constituting a fuel cell stack.
In a manufacturing process of a single cell 10 in which a frame-integrated membrane electrode assembly MEAf having plasticity is sandwiched between two plates SPc, SPa constituting a separator SP and thermocompression bonding is performed, temporary assembly before thermocompression bonding is performed. Then, high pressure air is introduced into the cathode electrode side of the single cell 10 and the pressure loss is measured. The single cell 10 is thermocompression bonded while adjusting the load applied to the temporarily assembled single cell 10 so that the pressure loss falls within a predetermined range. The fuel cell stack 100 is configured by stacking single cell groups manufactured according to this process and having a reduced pressure loss difference.
[Selection] Figure 7

Description

  The present invention relates to a fuel cell.

  A fuel cell is usually configured as a fuel cell stack in which single cells as power generation modules are stacked. However, when the difference in power generation performance for each single cell in the fuel cell stack is significant, the power generation efficiency of the fuel cell stack as a whole may be reduced. Until now, various techniques have been proposed for such a problem (Patent Document 1, etc.).

JP 2000-208161 A JP2003-151604

  For example, in Patent Document 1, the cell voltage for each single cell is measured during power generation of the fuel cell stack, the standard deviation is obtained, and the gas flow rate and load current supplied to the fuel cell stack are reduced so that the standard deviation is reduced. A technique for controlling the above has been proposed. However, with this technique, even if the standard deviation of the cell voltage can be suppressed to some extent, the difference in power generation performance for each single cell has not been eliminated.

  Further, in Patent Document 2, before assembling a single cell to the fuel cell stack, the pressure loss of the supplied oxidizing gas is measured for each single cell, and the single cells that generate the same pressure loss are combined to form a fuel cell stack. The technology which comprises is proposed. According to this method, it is possible to suppress a difference in power generation performance for each single cell in the same fuel cell stack, but there is a possibility that a difference occurs in power generation performance for each fuel cell stack.

  Thus, in the past, the actual situation is that no sufficient contrivance has been made to reduce the difference in power generation performance of each unit cell of the fuel cell stack.

  An object of this invention is to provide the technique which improves the nonuniformity of the electric power generation performance for every single cell which comprises a fuel cell stack.

  In order to achieve the above object, the present invention provides a method for producing a single cell that is a power generation module constituting a fuel cell, and (a) a membrane electrode assembly is sandwiched between plates constituting a separator and a temporary assembly is performed. A step of preparing the performed single cell; (b) supplying and discharging an inflow gas to the single cell and measuring an inflow gas pressure loss of the single cell; and (c) an inflow gas of the single cell. A step of joining the membrane electrode assembly and the plate while applying a load to the single cell so that the pressure loss is within a predetermined range.

  According to this method, the difference in pressure loss for each single cell can be reduced, and the non-uniformity (variation) in power generation performance for each single cell, which has been caused by the difference in pressure loss, can be improved.

  The membrane electrode assembly may include a plastic gas diffusion layer, and the gas diffusion layer may have a thickness that changes according to a load applied to the single cell in the step (c).

  According to this method, the thickness of the gas diffusion layer of the single cell is changed by the load applied to the single cell in the step (c), and thereby the pressure loss of the single cell can be adjusted.

  The separator has a gas flow path, and in the step (c), an effective part of the gas flow path is obtained when a part of the membrane electrode assembly enters according to a load applied to the single cell. It is also possible to change the cross-sectional area of the flow path.

  According to this method, by applying a load to the single cell in the step (c), a part of the membrane electrode assembly is caused to enter the gas flow path provided in the separator, so that the effective cross-sectional area of the gas flow path is increased. Can be changed, thereby adjusting the pressure loss of the single cell.

  The inflow gas may be an oxidizing gas.

  According to this method, it is possible to reduce the difference in pressure loss of the oxidizing gas supplied to the cathode electrode layer side that has a particularly large influence on the difference in power generation performance for each single cell.

  The present invention may include a step of manufacturing a plurality of single cells according to the above manufacturing method, and (d) a step of stacking the plurality of single cells and assembling a fuel cell stack.

  According to this method, it is possible to manufacture a fuel cell stack in which the difference in power generation performance for each single cell is within a predetermined range.

  The load applied to the single cell applied in the step (c) may be larger than the fastening load applied to the fuel cell stack in the step (d).

  According to this method, the possibility that the pressure loss of each single cell changes due to the fastening load applied when the fuel cell stack is configured can be reduced.

  The present invention can be realized in various forms, for example, a single cell manufactured by the manufacturing method of the present invention, a fuel cell stack including the single cell, and a fuel including the fuel cell stack. It can be realized in the form of a battery system, a vehicle equipped with the fuel cell system, and the like.

A. Fuel cell stack configuration:
FIG. 1A is a schematic diagram showing the configuration of a fuel cell stack as one embodiment of the present invention. The fuel cell stack 100 in this embodiment is a polymer electrolyte fuel cell that receives supply of fuel gas and oxidant gas and generates electric power through its electrochemical reaction (fuel cell reaction). Specifically, hydrogen is supplied as the fuel gas, and high-pressure air containing oxygen is supplied as the oxidizing gas. The fuel cell stack may not be a polymer electrolyte fuel cell, and the present invention can be applied to any of various types of fuel cells.

  The fuel cell stack 100 has a stack structure in which single cells 10 that are power generation modules described later are stacked. The cell stack 40 that is a group of single cells stacked is sandwiched by the end plate 20 and fastened by receiving a load by the fastening member 30.

  FIG. 1B is a schematic diagram showing the configuration of the single cell 10. The single cell 10 includes a frame-integrated membrane electrode assembly MEAf and a separator SP, which will be described later. The separator SP is a two-layer separator configured by an anode plate SPa and a cathode plate SPc described later. The single cell 10 is configured by sandwiching a frame-integrated membrane electrode assembly MEAf between one cathode plate SPc and the other anode plate SPa of two separators SP. That is, the cell stack 40 in which the single cells 10 are stacked has a structure in which the frame-integrated membrane electrode assembly MEAf and the separator SP are alternately stacked.

  FIG. 2A is a schematic diagram showing the configuration of the frame-integrated membrane electrode assembly MEAf. The frame-integrated membrane electrode assembly MEAf includes a power generation unit 11 in which a fuel cell reaction is performed and a frame unit 12 that is an outer peripheral frame surrounding the power generation unit 11. The frame portion 12 is provided with manifold holes M1 to M6 which are through holes for supplying and discharging hydrogen, air, refrigerant and the like to each single cell. Specifically, the configuration is as follows.

  The manifold hole M1 is responsible for supplying hydrogen, and the manifold hole M2 is responsible for discharging anode exhaust gas containing hydrogen that has not been subjected to the reaction. The manifold hole M3 is responsible for the supply of air, and the manifold hole M4 is responsible for the discharge of cathode exhaust gas containing oxygen that has not been subjected to the reaction and moisture generated by the reaction. The manifold holes M5 and M6 are responsible for supplying and discharging a refrigerant (water) for cooling the heat of the fuel cell stack 100 generated by power generation. The supply manifold holes M1, M3, and M5 are provided at positions facing the corresponding discharge manifold holes M2, M4, and M6 with the power generation unit 11 in between. The manifold holes may have other configurations / arrangements.

  FIG. 2B is a cross-sectional view showing a cross section taken along the line BB shown in FIG. The power generation unit 11 includes an electrolyte membrane 13 that exhibits good proton conductivity in a wet state. The electrolyte membrane 13 is sandwiched between the cathode electrode layer 14c and the anode electrode layer 14a to constitute a membrane electrode assembly MEA (Mebrane Electrode Assembly). Each of the two electrode layers 14c and 14a is provided with a catalyst layer (not shown) on which a catalyst for promoting a fuel cell reaction is supported. For example, platinum (Pt) can be employed as the catalyst.

  Gas diffusion layers 15c and 15a are provided on the outer surfaces of the two electrode layers 14c and 14a of the membrane electrode assembly MEA that are not in contact with the electrolyte membrane 13 to spread hydrogen and air over the entire electrode layers 14c and 14a. Yes. The gas diffusion layers 15c and 15a can be made of a porous material such as carbon or sintered metal. Moreover, the gas diffusion layers 15c and 15a can also be comprised by an expanded metal. Here, the expanded metal is provided by staggered cuts in a metal plate such as stainless steel having a thickness of about 0.1 mm to 0.2 mm, and by alternately pushing the surfaces sandwiching the cuts in opposite directions, A large number of through holes having a hole diameter of 0.1 mm to 1 mm are formed as a mesh on the step.

  The frame portion 12 has a configuration in which two resin frames 12f are joined by an adhesive layer 12g. A phenol resin or the like can be used as the resin frame 12f. By the way, the electrolyte membrane 13 of the membrane electrode assembly MEA has an outer peripheral end portion 13e which is a portion protruding from the outer peripheral edge of the electrode layers 14c and 14a. The membrane electrode assembly MEA and the frame portion 12 are integrated by the outer peripheral end portion 13e being held by the adhesive layer 12g while being sandwiched by the inner peripheral edge of the resin frame 12f of the frame portion 12. Note that the outer peripheral end portion 13e reduces the possibility of occurrence of a cross leak that causes hydrogen to move to the cathode side without being subjected to a reaction during power generation of the fuel cell.

  FIG. 3A is a schematic diagram showing an anode plate SPa that constitutes the separator SP, and FIGS. 3B to 3D are cross-sectional views taken along the line BB shown in FIG. Sectional drawing in cutting and DD cutting is shown. The anode plate SPa can be composed of a thin metal plate having conductivity. When the anode plate SPa is assembled as a single cell 10, the anode plate SPa covers the gas diffusion layer 15a on the anode electrode layer 14a side of the frame-integrated membrane electrode assembly MEAf.

  Like the frame-integrated membrane electrode assembly MEAf, the anode plate SPa is provided with manifold holes M1 to M6 which are through holes. An inflow hole P1, which is a through hole for guiding hydrogen to the gas diffusion layer 15a of the single cell 10, is provided in the vicinity of the hydrogen supply manifold hole M1. Further, an outflow hole P2, which is a through hole for guiding the anode exhaust gas from the gas diffusion layer 15a to the outside, is provided in the vicinity of the hydrogen discharge manifold hole M2. A specific flow of hydrogen will be described later.

  FIG. 4A is a schematic view showing a cathode plate SPc constituting the separator SP, and FIGS. 4B to 4D are respectively a BB cut and a CC line shown in FIG. Sectional drawing in cutting and DD cutting is shown. The cathode plate SPc can be formed of a thin metal plate having conductivity. When the cathode plate SPc is assembled as the single cell 10, the cathode plate SPc covers the gas diffusion layer 15c on the cathode electrode layer 14c side of the frame-integrated membrane electrode assembly MEAf.

  As with the anode plate SPa, manifold holes M1 to M6 are provided in the cathode plate SPc. Further, the cathode plate SPc is provided with thin portions AP, CP, and WP that are processed to be thin on the surface that comes into contact with the anode plate SPa when assembled as the separator SP. That is, when assembled as the separator SP, these thin-walled portions AP, CP, and WP together with the anode plate SPa form the anode channel AP, the cathode channel CP, and the refrigerant channel WP.

  The two anode channels AP are provided so as to communicate with the hydrogen manifold holes M1 and M2, respectively, and communicate with the inflow hole P1 and the outflow hole P2 of the anode plate SPa. The two cathode flow paths CP communicate with the air manifold holes M3 and M5, respectively. The cathode flow path CP that communicates with the air supply manifold hole M3 is provided with an inflow hole P3 that is a through hole for guiding air to the gas diffusion layer 15c. The cathode passage CP communicating with the air exhaust manifold hole M4 is provided with an outflow hole P4 which is a through hole for guiding the cathode exhaust gas from the gas diffusion layer 15c to the outside. The refrigerant flow path WP communicates the refrigerant supply manifold hole M5 and the refrigerant discharge manifold hole M6, and when assembled as the single cell 10, the refrigerant flows into the power generation section 11 of the frame-integrated membrane electrode assembly MEAf. (FIG. 2) is provided so that the whole can be cooled.

  FIGS. 5A to 5C are explanatory diagrams for explaining the flow of fluid (anode gas and cathode gas, refrigerant) in the single cell 10 when generating power as the fuel cell stack 100. In the present specification, the term “anode gas” means both the fuel gas supplied to the anode electrode layer and the anode exhaust gas. Similarly, when referred to as “cathode gas”, it means both oxidizing gas and cathode exhaust gas supplied to the cathode electrode layer.

  5A to 5C show cross sections in each manifold hole of an arbitrary single cell 10 of the cell stack 40 (FIG. 1). Specifically, FIG. 5A is a cross section at the manifold holes M1 and M3, FIG. 5B is a cross section at the manifold holes M5 and M6, and FIG. 5C is a cross section at the manifold holes M2 and M4. It is. In each figure, the anode plate SPa and cathode plate SPc of adjacent single cells are also shown.

  First, the flow of the anode gas will be described. As indicated by arrows in FIG. 5A, a part of the hydrogen supplied to the hydrogen supply manifold hole M1 flows into the anode plate SPa through the anode flow path AP provided in the cathode plate SPc. The hole P1 leads to the gas diffusion layer 15a. As indicated by the arrow in FIG. 5C, the anode exhaust gas flows from the outflow hole P2 provided in the anode plate SPa to the cathode flow path CP provided in the cathode plate SPc and into the hydrogen discharge manifold hole M2. As a result, the fuel cell stack 100 is discharged to the outside.

  Next, the flow of the cathode gas will be described. As indicated by an arrow in FIG. 5A, a part of the air supplied to the air supply manifold hole M3 passes through the cathode flow path CP provided in the cathode plate SPc, and passes through the gas diffusion layer 15c from the inflow hole P3. It leads to. As shown by an arrow in FIG. 5C, the cathode exhaust gas passes through an outflow hole P4 provided in the cathode plate SPc and a cathode flow path CP provided in the cathode plate SPc from the gas diffusion layer 15c and an air discharge manifold. It reaches the hole M4 and is discharged to the outside of the fuel cell stack 100.

  Next, the flow of the refrigerant will be described. As indicated by arrows in FIG. 5B, a part of the refrigerant supplied to the refrigerant supply manifold hole M5 flows into the refrigerant flow path WP provided in the cathode plate SPc. The refrigerant reaches the refrigerant discharge manifold hole M6 as it is from the refrigerant flow path WP together with the heat generated by the fuel cell reaction, and is discharged to the outside of the fuel cell stack 100.

  With the above configuration, the fuel cell stack 100 generates power for each single cell 10, and the generated electricity is collected by the separator SP, and the power of the fuel cell stack 100 as a whole is obtained. Generally, in such a fuel cell stack, when the difference in power generation performance for each single cell is significant, the power generation efficiency of the fuel cell stack as a whole decreases. In many cases, such a difference in power generation performance between single cells is considered to be caused by an error in the manufacturing process. Therefore, as an embodiment of the present invention, a method for manufacturing the single cell 10 and the fuel cell stack 100 that can reduce the difference in power generation performance of the single cell 10 will be described below.

B. Manufacturing method of single cell and fuel cell stack:
FIG. 6 is an explanatory view showing a single cell manufacturing apparatus 200 used for manufacturing the single cell 10 as an embodiment of the present invention. This single cell manufacturing apparatus 200 is an apparatus for crimping the two plates SPc and SPa constituting the separator SP and the frame-integrated membrane electrode assembly MEAf.

  The single cell manufacturing apparatus 200 includes a cathode crimping plate 201 that applies a load from the cathode side of the single cell 10 and an anode crimping plate 202 that applies a load from the anode side. Each of the two crimping plates 201 and 202 is provided with a heater 205 so that heat can be applied to the single cell 10 with the single cell 10 sandwiched therebetween. The cathode crimping plate 201 is provided with an adjacent anode plate SPan having a configuration similar to that of the anode plate SPa on the surface in contact with the single cell 10. Similarly, the anode crimping plate 202 is provided with an adjacent cathode plate SPcn having a configuration similar to that of the cathode plate SPc on the surface in contact with the single cell 10.

  The temporarily assembled single cell 10 is set in the single cell manufacturing apparatus 200. Here, the temporarily assembled unit cell 10 refers to a state in which the frame-integrated membrane electrode assembly MEAf is sandwiched between the cathode plate SPc and the anode plate SPa but not yet joined. Note that the frame-integrated membrane electrode assembly MEAf may be in a state where the resin frame 12f of the frame portion 12 has already been bonded by the adhesive layer 12g, or may be bonded in this step.

  FIG. 7 shows a state in which the single cell 10 is sandwiched between two crimping plates 201 and 202 and two adjacent plates SPan and SPcn. At this time, the cathode plate SPc constitutes the first temporary separator TS1 together with the adjacent anode plate SPan, and the anode plate SPa constitutes the second temporary separator TS2 together with the adjacent cathode plate SPcn. Therefore, the frame-integrated membrane electrode assembly MEAf is sandwiched between the two temporary separators TS1 and TS2.

  Further, in this state, the manifold holes M1 to M6 of the single cell 10 are closed by the two crimping plates 201 and 202. However, an air inflow path 203 and an air outflow path connected to the air manifold holes M3 and M5 so that high-pressure air can flow into the cathode crimping plate 201 in this state into the cathode electrode layer side of the single cell 10. 204 is provided.

  The air inflow path 203 is connected to the air supply pipe 211 of the air supply unit 210. An air compressor 212, a pressure regulating valve 214, and a pressure meter 213 are provided from the upstream in the air supply pipe 211 of the air supply unit 210. In addition, the air outflow path 204 is connected to the air discharge pipe 221 of the air discharge unit 220. A pressure meter 222 and a pressure regulating valve 223 are provided from the upstream to the air discharge pipe 221 of the air discharge unit 220. The air supply unit 210 and the air discharge unit 220 may be connected to the cathode pressure-bonding plate 201 before the unit cell 10 temporarily assembled in the unit cell manufacturing apparatus 200 is sandwiched.

  With this configuration, in the single cell manufacturing apparatus 200, high-pressure air can flow into the single cell 10 when the separator SP and the frame-integrated membrane electrode assembly MEAf are bonded. Therefore, the pressure loss of the introduced high-pressure air can be measured by the pressure meters 213 and 222. The term “pressure loss of a single cell” means the pressure loss of the gas flowing into the single cell.

  In general, the power generation performance of a single cell varies depending on the pressure loss of fuel gas and oxidant gas flowing into the single cell. This is because in the cell stack, the inflow amount of the supplied gas decreases as the single cell has a larger pressure loss. Therefore, in the single cell manufacturing process, by adjusting the magnitude of the pressure loss of each single cell to be within a predetermined range, the difference in power generation performance of each single cell is reduced, and the power generation efficiency of the fuel cell stack Can be improved.

  FIG. 8A is a graph showing the relationship between the load applied to the single cell 10 by the single cell manufacturing apparatus 200 and the thickness of the single cell 10. As can be seen from this graph, the thickness of the single cell is reduced according to the load applied by the cell manufacturing apparatus 200. This is because, among the constituent members of the single cell 10, the thicknesses of the gas diffusion layers 15a and 15c are mainly reduced by the load.

  FIG. 8B is a graph showing the relationship between the load applied to the single cell 10 by the single cell manufacturing apparatus 200 and the pressure loss of the single cell 10. As can be seen from this graph, the pressure loss of the single cell 10 tends to increase as the load applied to the single cell 10 increases. This is because, when a load is applied to the single cell 10 and the thickness of the gas diffusion layers 15a and 15c is reduced, the flow path of the fluid in the gas diffusion layers 15a and 15c is compressed and the resistance to the fluid increases. It is considered that the pressure loss increases.

  Therefore, in the single cell manufacturing apparatus 200 of the present embodiment, the thickness of the single cell 10 is adjusted by adjusting the load applied to the single cell 10 so that the pressure loss falls within a predetermined range, and the pressure between each single cell is adjusted. Reduce the difference in loss. Specifically, the following procedure is used.

  An initial load is applied to the single cell 10 by the single cell manufacturing apparatus 200 so that air leakage does not occur from the contact surface of each member even when high pressure air flows in. Measure pressure loss. From the relationship between the pressure loss and the load as shown in the graph of FIG. 8B obtained in advance by experiments or the like, a load to be further applied to the initial load is obtained in order to obtain a desired pressure loss. Applying the load thus obtained, the pressure loss is measured again. This process can be repeated to adjust the pressure loss.

  When the desired pressure loss is obtained, the single cell 10 is heated by the heater 205. At this time, the frame portion 12 of the frame-integrated membrane electrode assembly MEAf and the plates SPa and SPc are heat-sealed on the bonding surface CS. The gas diffusion layers 15a and 15c have a property (plasticity) that retains the thickness after the change even when the load is changed and the thickness of the gas diffusion layers 15a and 15c is not received. It is preferable to have. If it does in this way, it can prevent that the pressure loss of the single cell 10 changes after the adhesion process by the single cell manufacturing apparatus 200.

  By assembling the single cell group thus manufactured as a fuel cell stack 100 as shown in FIG. 1, a fuel cell stack having higher power generation efficiency than the conventional fuel cell stack can be obtained. When the fuel cell stack 100 is assembled, the fastening load applied to the cell stack by the fastening member 30 is preferably smaller than the smallest load among the loads applied to each single cell by the single cell manufacturing apparatus 200. If it does in this way, when unit cell 10 is assembled as a fuel cell stack, it can control that the pressure loss of unit cell 10 changes with the conclusion load received from fastening member 30. Therefore, it is possible to suppress a decrease in power generation efficiency of the fuel cell stack.

C. Variation:
The present invention is not limited to the above-described examples and embodiments, and can be implemented in various modes without departing from the gist thereof. For example, the following modifications are possible.

C1. Modification 1:
In the above embodiment, the separator SP is a two-layer separator composed of two plates SPa and SPc. However, the separator SP may not be a two-layer separator. For example, a three-layer separator having an intermediate plate between the anode plate and the cathode plate may be used. The frame-integrated membrane electrode assembly MEAf may be a seal-integrated membrane electrode assembly in which a sealing member such as a seal gasket is formed on the outer periphery of the membrane electrode assembly MEA instead of the frame portion 12.

C2. Modification 2:
Instead of the separator SP of the above embodiment, a separator in which a groove-like gas flow path is provided on the surface in contact with the membrane electrode assembly MEAf may be adopted. In this case, since part of the membrane electrode assembly MEAf (for example, the gas diffusion layers 15a and 15c) enters the gas flow path according to the load applied to the single cell by the single cell manufacturing apparatus 200, The effective channel cross-sectional area decreases and the pressure loss increases. Therefore, the pressure loss of the single cell can be adjusted also with this configuration, and the decrease in power generation efficiency of the fuel cell can be suppressed. In this case, the gas electrode diffusion layers 15a and 15c may not be provided in the membrane electrode assembly MEAf.

C3. Modification 3:
In the above embodiment, the pressure loss of the cathode gas is measured and the load applied to the single cell 10 is adjusted. However, the pressure loss of the anode gas may be measured. However, since the reaction rate of hydrogen is high, a difference in power generation performance hardly occurs due to a difference in hydrogen supply amount (difference in pressure loss). On the other hand, when air is used as the oxidizing gas as in the above embodiment, the oxygen concentration is low (about 20%) in the air, so that a difference in power generation performance is likely to occur due to the difference in supply amount. In addition, when the cathode gas pressure improves the drainage performance on the cathode electrode side, if the cathode gas flow rate decreases due to pressure loss, so-called flooding occurs, which causes excessive moisture on the cathode electrode side, generating power. Performance decreases. That is, even in this case, a difference in power generation performance due to a difference in pressure loss is likely to occur. Therefore, it is preferable to measure the pressure loss of the cathode gas as in the above embodiment.

C4. Modification 4:
In the above embodiment, the frame-integrated membrane electrode assembly MEAf and the two plates SPa, SPc are thermocompression bonded, but may be bonded by a method other than thermocompression bonding. For example, it is good also as what is joined using an adhesive agent. In this case, the single cell manufacturing apparatus 200 may not have the heater 205.

C5. Modification 5:
In the above embodiment, the gas diffusion layers 15a and 15c may be made of a member having no plasticity, and the single cell 10 as a whole is configured such that the pressure loss of the single cell 10 changes by receiving a load. It may be good. For example, by applying a load to the single cell 10, the cross-sectional area of the cathode channel provided in the separator SP may be reduced and the pressure loss may be increased.

Schematic which shows the structure of a fuel cell stack and a single cell. Schematic which shows the structure of a frame-integrated membrane electrode assembly. Schematic which shows the structure of the anode plate which comprises a separator. Schematic which shows the structure of the cathode plate which comprises a separator. Schematic for demonstrating the flow of the fluid in a single cell. Explanatory drawing for demonstrating a single cell manufacturing apparatus. Explanatory drawing for demonstrating a single cell manufacturing apparatus. The graph which shows the relationship between the load applied to a single cell, and the thickness of a single cell, and the graph which shows the relationship between the load applied to a single cell, and the pressure loss of a single cell.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Single cell 11 ... Power generation part 12 ... Frame part 12f ... Resin frame 12g ... Adhesive layer 13 ... Electrolyte film 13e ... Outer peripheral edge part 14a ... Anode electrode layer 14c ... Cathode electrode layer 15a, 15c ... Gas diffusion layer 20 ... End plate DESCRIPTION OF SYMBOLS 30 ... Fastening member 40 ... Cell stack 100 ... Fuel cell stack 200 ... Single cell manufacturing apparatus 201 ... Cathode pressure bonding plate 202 ... Anode pressure bonding plate 203 ... Air inflow path 204 ... Air outflow path 205 ... Heater 210 ... Air supply part 211 ... Air Supply pipe 212 ... Air compressor 213 ... Pressure meter 214 ... Pressure control valve 220 ... Air discharge part 221 ... Air discharge pipe 222 ... Pressure meter 223 ... Pressure control valve AP ... Anode channel CP ... Cathode channel CS ... Adhesion surface M1 M6 ... Manifold hole MEA ... Membrane electrode bonding MEAf: Frame-integrated membrane electrode assembly P1, P3 ... Inflow hole P2, P4 ... Outflow hole SP ... Separator SPa ... Anode plate SPan ... Adjacent anode plate SPc ... Cathode plate SPcn ... Adjacent cathode plate TS1, TS2 ... Temporary separator WP ... Refrigerant flow path

Claims (9)

A method of manufacturing a single cell, which is a power generation module constituting a fuel cell,
(A) preparing a single cell that is temporarily assembled by sandwiching a membrane electrode assembly with a plate constituting a separator;
(B) supplying and discharging inflow gas to and from the single cell, and measuring the inflow gas pressure loss of the single cell;
(C) joining the membrane electrode assembly and the plate while applying a load to the single cell so that the inflow gas pressure loss of the single cell is within a predetermined range;
A manufacturing method comprising: The manufacturing method according to claim 1,
The membrane electrode assembly includes a gas diffusion layer having plasticity,
The said gas diffusion layer is a manufacturing method with which thickness changes according to the load applied to the said single cell in the said process (c). The manufacturing method according to claim 1 or 2,
The separator has a gas flow path,
In the step (c), an effective channel cross-sectional area of the gas channel changes when a part of the membrane electrode assembly enters the gas channel according to a load applied to the single cell. ,Production method. It is a manufacturing method of Claim 1 thru | or 3, Comprising:
The manufacturing method, wherein the inflow gas is an oxidizing gas. A method for manufacturing a fuel cell stack, comprising:
Producing a plurality of single cells according to the production method according to claim 1;
(D) stacking the plurality of single cells and assembling a fuel cell stack;
A manufacturing method comprising: It is a manufacturing method of Claim 5, Comprising:
The manufacturing method in which the load applied to the single cell in the step (c) is larger than the fastening load applied to the fuel cell stack in the step (d). A fuel cell stack,
Provided with a plurality of single cells sandwiching the membrane electrode assembly with the plate constituting the separator,
The fuel cell stack, wherein the thickness of each of the plurality of single cells is adjusted so that the pressure loss of the gas flowing into each single cell is within a predetermined range. The fuel cell stack according to claim 7, wherein
The membrane electrode assembly includes a gas diffusion layer having plasticity,
The unit cell is a fuel cell stack in which the pressure loss is adjusted by the thickness of the gas diffusion layer. The fuel cell stack according to claim 7 or 8, wherein
The separator has a gas flow path,
The unit cell is a fuel cell stack in which the pressure loss is adjusted by an amount by which a part of the membrane electrode assembly penetrates into the gas flow path.

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