JP4872287B2 - Separator assembly and planar polymer electrolyte fuel cell for planar polymer electrolyte fuel cell - Google Patents

Description

  The present invention relates to a planar polymer electrolyte having a pair of a fuel supply separator and an oxygen supply separator used in a planar polymer electrolyte fuel cell in which unit cells are planarly arranged in one direction. The present invention relates to a separator assembly for a type fuel cell and a surface-type polymer electrolyte fuel cell using the separator.

Recently, expectations for fuel cells have increased rapidly from the standpoint of protecting the global environment, using hydrogen as a direct fuel, and having high energy conversion efficiency.
Until now, it has been used for space development and marine development, but recently, it has been expanded to be used as a power generator for home use instead of an automobile engine, and it has become more likely to be widely used.
A fuel cell is simply a device that continuously supplies fuel (reducing agent) and oxygen or air (oxidant) from the outside, and reacts electrochemically to extract electrical energy. Recently, depending on the type of electrolyte used, it is largely divided into solid oxide fuel cell (SOFC), molten carbonate fuel cell (MCFC), phosphoric acid. Generally, the fuel cell is classified into five types: a fuel cell (PAFC), a polymer electrolyte fuel cell (PEFC), and an alkaline aqueous fuel cell (AFC).
These use hydrogen gas generated from methane or the like as a fuel. Recently, a direct methanol fuel cell (DMFC) that directly uses an aqueous methanol solution as a fuel is also known.

Under such circumstances, a solid polymer membrane is composed of two types of electrodes sandwiched between two types of electrodes, and these members are sandwiched between separators (this is a polymer electrolyte fuel cell). Hereinafter, PEFC (Polymer Electrolyte Fuel Cell) is also drawing attention.
In this PEFC, a unit cell is configured by arranging electrodes such as an air electrode (oxygen electrode) and a fuel electrode (hydrogen electrode) on both sides of a solid polymer membrane, and both sides of the unit cell are sandwiched between fuel cell separators. It has a configuration.
A fuel electrode and an air electrode comprising a catalyst layer having a thickness of 10 μm to 20 μm are formed and integrated on both sides of a polymer electrolyte having a thickness of 20 μm to 70 μm, and a porous support layer (carbon paper, pores) as a current collector on the outside of the catalyst layer. And a separator (partition plate) that also serves as a supply path for a reactive gas such as hydrogen or oxygen.
In order to prevent direct reaction between the fuel (hydrogen) and the oxidant (air), it is necessary to isolate them and to carry hydrogen ions (protons) generated at the fuel electrode to the air electrode side.
A fuel cell that operates at room temperature (100 ° C or less) and moves protons in a solid polymer membrane. The solid polymer membrane has a thin film (thickness) with a perfluorocarbon sulfonic acid structure that has sulfonic acid groups as ion exchange groups. Can be used, and a compact battery can be manufactured.
The output performance is 1 to 3 A / cm ² , 0.6 to 2.1 V / single cell, and a high output density of 2.1 W / cm ² can be obtained.
As a PEFC separator, a graphite plate is currently cut out and grooved, but it is expensive in terms of cost.
For this reason, development of a carbon compound moldable separator in which carbon is kneaded into a resin is in progress, but this is problematic in terms of strength.
In addition, metal separators are expected to solve these cost problems and strength problems, but there is a problem in corrosion resistance.
Each of these separators is formed with a groove for supplying fuel gas and / or a groove for supplying oxidant gas as required.
From the aspect of corrosion resistance, a form in which gold plating or the like is applied is also employed.

The PEFC generally has a stack structure in which a plurality of unit cells each having an electrode are stacked on both sides of a solid polymer film and electrically connected to each other.
In the case of this structure, a fuel gas groove for supplying fuel gas to one adjacent unit cell is generally formed on one side surface of the separator for a fuel cell, and the other unit cell adjacent to the other side cell is formed on the other side surface. An oxidant gas groove for supplying oxidant gas is formed.
In such a separator, fuel gas and oxidant gas are supplied along the separator surface.

In addition to this stack structure, the PEFC is a planar type constructed by arranging a plurality of unit cells each having electrodes arranged on both sides of a solid polymer film and electrically connecting them. In recent years, however, development and improvement have been actively made for use as a power source for a portable terminal, which requires a thin electromotive force without requiring an electromotive force so much.
However, in the case of a planar type in which a plurality of unit cells are arranged in a plane and are electrically connected, there is a problem that the supply of fuel and oxygen becomes uneven depending on the location.
Therefore, in order to improve the non-uniformity of the fuel supply, a large number of through holes are formed in the direction perpendicular to the surface of the separator in contact with the membrane electrode assembly (MEA). A separator having a structure for supplying oxygen is considered. (See Patent Document 1)
Here, a composite including an electrode portion positioned between the fuel supply side separator and the oxygen supply side separator of the fuel cell, for example, a current collector layer, a fuel electrode, a polymer electrolyte, an oxygen electrode, A composite such as a film formed by stacking current collector layers is referred to as a membrane electrode composite (MEA).
JP, 2003-203647, A The applicant of this application has proposed such a plane type PFEC and a plane type separator used for it in Japanese Patent Application No. 2004-292268 (patent documents 2). Japanese Patent Application No. 2004-292268

Such a planar PEFC will be briefly described with reference to a planar methanol fuel cell (DMFC) that directly uses a methanol aqueous solution as a fuel as shown in FIG. Keep it.
FIG. 7 is a block diagram showing an example of a planar PEFC (Polymer Electrolyte Fuel Cell) 10 incorporating a pair of fuel supply side separator 20 and oxygen supply side separator 30, and FIG. 8 is shown in FIG. It is the figure which showed the state which spaced apart each member of the planar type PEFC.
In FIG. 7, PEFC (Polymer Electrolyte Fuel Cell) 10 includes a battery body 10A in which a membrane electrode assembly (MEA) 40 is sandwiched between a pair of fuel supply side separator 20 and oxygen supply side separator 30, and a case body. 60.

In the battery main body 10 </ b> A, the fuel supply side separator 20 and the oxygen supply side separator 30 are bent at connecting hinge portions (not shown), and the respective insulating frames of the fuel supply side separator 20 and the oxygen supply side separator 30 are. 23 and 33 are arranged to face the membrane electrode assembly (MEA) 40.
In addition, current collectors 21 </ b> A and 31 </ b> A of the fuel supply side separator 20 and the oxygen supply side separator 30 are in contact with the membrane electrode assembly (MEA) 40 through the carbon paper 51 and 52.
The membrane electrode assembly (MEA) 40 includes a fuel electrode side catalyst layer 43 on the fuel supply side separator 20 side, and an oxygen electrode side catalyst layer 44 on the oxygen supply side separator 30.
Here, as shown in FIG. 8, the fuel supply side separator 20 and the oxygen supply side separator 30 are sandwiched between a pair of frame bodies 22 and 23 and frame bodies 32 and 33, respectively. The frame bodies 23 and 33 on the side of the composite (MEA) 40 open the entire cell region, but the outer frame bodies 22 and 32 are arranged in order to improve the adhesion of the current collectors 21A and 31A. The through portions 22a and 32a are provided so that the electric portions 21A and 31A can be pressed.
The conductive substrate 21 (31) of the separator 20 on the fuel supply side shown in FIGS. 7 and 8 is laminated with the frame bodies 22 and 23 on both sides thereof as shown in the perspective view of FIG.
In this case, the frame body 23 that opens the entire cell region is the membrane electrode assembly (MEA) 40 side.
FIG. 10 is a perspective view showing the parts in FIG. 9 apart from each other.
The same applies to the separator 30 on the oxygen supply side, and the conductive substrate 31 is laminated with frame bodies 32 and 33 on both sides thereof as shown in the perspective view of FIG.
And the frame 33 which has opened the whole cell area | region is laminated | stacked as the membrane electrode assembly (MEA) 40 side.

Thus, the three unit cells 81, 82, 83 are arranged in a plane.
The current collector 31A (unit conductive substrates 31a, 31b, 31c) and the current collector 21A (unit conductive substrates 21a, 21b, 21c) between the three unit cells 81, 82, 83 are connected hinges. It is electrically connected via a part (not shown).
Here, the connecting hinge portion may be covered with an insulating resin to provide an insulating coating. Further, in the battery main body 10A described above, the peripheral end portion of the membrane electrode assembly (MEA) 40 is sandwiched between the outer peripheral frame portions of the separators 20 and 30 via the seal member 70.
The battery body 10 </ b> A is fixed to the case body 60 via the seal member 70 using fixing bolts 90.

Further, an electrode terminal 37 connected to the unit conductive substrate 31a of the oxygen supply side separator 30 constituting the unit cell 81 is provided.
Further, an electrode terminal 27 connected to the unit conductive substrate 23 a of the fuel supply side separator 20 constituting the unit cell 83 is provided.
As a result, the three unit cells 81, 82, and 83 are electrically connected in series including the connection by the connecting hinge portion as follows.

In such a PEFC (Polymer Electrolyte Fuel Cell) 10, three unit cells 81, 82, 83 are connected by a connecting hinge portion, and there is no need for a connecting step using a connecting member, and The contact resistance is extremely low and the power generation characteristics are high.
In order to arrange the hinges without taking time when manufacturing the PEFC, conventionally, the connection hinge portions are formed by connecting the unit conductive substrates 21 a to 21 c and 31 a to 31 c of the separators 20 and 30. When producing by etching process etc.
Together with these, the connecting hinge portion forming portion is integrally connected.
However, the connecting hinge manufactured in this way has a problem that it cannot withstand repeated bending when manufacturing the PEFC.
For this reason, the predetermined part of the connecting hinge part forming part is further thinned by a die press to be easily bent, but in this case, the connecting hinge itself is manufactured by etching or the like. In addition to the outer shape processing, it is necessary to perform a thinning process by a die press, which is troublesome and problematic.

As described above, in recent years, the development and application of fuel cells have progressed more and more, and recently, the use as a power source for mobile terminals, which requires flat electromotive force and is as thin as possible without requiring much electromotive force. Since then, the development and improvement of planar PEFC has been actively conducted.
Under such circumstances, in the planar type PEFC, a connecting hinge for electrically connecting the fuel supply side separator and the oxygen supply side separator is used. However, each separator member is manufactured by conventional etching processing or the like. If the connecting hinge part forming part is formed, there is a problem that the hinge part forming part is less resistant to repeated bending, and the predetermined part of the hinge part forming part is further thinned by a die press. In this method, it is necessary to perform a thinning process in addition to the outer shape processing such as etching processing, and there is a problem that it takes time and effort, and these measures have been required.
The present invention corresponds to this, and specifically, a fuel supply separator, an oxygen supply separator used in a planar polymer electrolyte fuel cell in which unit cells are planarly arranged in one direction, Is a pair of separators, which is a connection part that can be easily connected to a fuel supply separator and an oxygen supply separator in place of a conventional connection hinge part, and does not require much labor. In addition, the present invention seeks to provide a separator assembly having a connection portion that can be formed and that can withstand repeated bending when manufacturing a PEFC.
Furthermore, the present invention intends to provide a separator assembly in which the fuel supply separator and the oxygen supply separator are compatible.
Furthermore, an object of the present invention is to provide a planar polymer electrolyte fuel cell using such a separator assembly.

The separator assembly for a planar polymer electrolyte fuel cell according to the present invention includes a fuel supply separator and an oxygen supply used in a planar polymer electrolyte fuel cell in which unit cells are arranged in one direction in a plane. A separator assembly for a planar polymer electrolyte fuel cell having a pair of separators for fuel, wherein the fuel supply separator and the oxygen supply separator each include a plurality of fuel supply or oxygen supply separators. A separator member in which n unit conductive substrates having through holes are arranged in one direction in a plane through a gap portion (n is an integer of 2 or more) and a separator member are integrated so as to sandwich the separator member. A pair of insulating frames, each of the pair of insulating frames having a predetermined opening corresponding to the arrangement position of the unit conductive substrates of each separator member, and the fuel One separator member of the supply separator and the oxygen supply separator is the first to (n-1) th unit conductive substrate at one end in the arrangement direction among the n unit conductive substrates. Has a connection terminal portion on the direction side orthogonal to the arrangement direction, and the other separator member corresponds to the one side in the arrangement direction among the n unit conductive substrates. The second to nth unit conductive substrates at the end of the side have a connection terminal portion on the direction side orthogonal to the arrangement direction, and further, the kth (k = 1 to (n-1)) unit conductive substrate connection terminal portions and k + 1-th unit conductive substrate connection terminal portions forming the other separator member are flexible printed wiring boards (FPCs). (Also called) , And it is characterized in that it is electrically connected.
A separator assembly for the above-described planar type polymer electrolyte fuel cell, wherein the fuel supply separator and the oxygen supply separator are made compatible with each other. It is.

The planar polymer electrolyte fuel cell of the present invention is a planar polymer electrolyte fuel cell in which unit cells are planarly arranged, and includes a fuel supply separator and an oxygen supply separator. One separator member of the fuel supply separator and the oxygen supply separator is from the first end (n-1) of one of the n unit conductive substrates in the arranged direction. The second unit conductive substrate has a connection terminal portion on the direction side orthogonal to the arrangement direction, and the other separator member has an arrangement direction of the n unit conductive substrates. The second to nth unit conductive substrates at the end corresponding to the one side have a connection terminal portion on the direction side perpendicular to the arrangement direction, and further, the one separator member is formed. Kth (k = 1 to (n-1) The connection terminal portion of the unit conductive substrate and the connection terminal portion of the (k + 1) th unit conductive substrate forming the other separator member are wiring formed on a flexible printed wiring board (also referred to as FPC). The unit is electrically connected, and n unit cells are electrically connected in series.
And it is said planar type polymer electrolyte fuel cell, Comprising: The separator assembly for planar type polymer electrolyte fuel cells of Claim 1 thru | or 2 is used, It is characterized by the above-mentioned. Is.

The separator assembly for a planar polymer electrolyte fuel cell according to the present invention is used in a planar polymer electrolyte fuel cell in which unit cells are arranged in one direction in a plane by having such a configuration. The separator assembly is a pair of a fuel supply separator and an oxygen supply separator, and can be easily connected to the fuel supply separator and the oxygen supply separator in place of the conventional connecting hinge portion. It is possible to provide a separator assembly including a connecting portion that can be formed easily and without trouble, and that can withstand repeated bending when manufacturing a PEFC. .
This further makes it possible to provide a flat polymer electrolyte fuel cell using such a separator assembly.
Specifically, each of the fuel supply separator and the oxygen supply separator includes a unit conductive substrate having a plurality of through holes for supplying fuel or supplying oxygen in one direction through a gap. n separators (n is an integer of 2 or more) arranged, and a pair of insulating frames integrated so as to sandwich the separator member, the pair of insulating frames The separator member has a predetermined opening corresponding to the arrangement position of the unit conductive substrate, and one separator member of the fuel supply separator and the oxygen supply separator has n units. Among the conductive substrates, the first to (n-1) th unit conductive substrates at one end in the arranged direction have a connection terminal portion on the direction side orthogonal to the arrangement direction. The other separator member is Among the n unit conductive substrates, the second to n-th unit conductive substrates at the ends corresponding to the one side in the arranged direction have connection terminals on the direction side perpendicular to the arrangement direction. A terminal portion for connection of a kth (k = 1 to (n−1)) unit conductive substrate forming the one separator member and the other separator member. This is achieved by being electrically connected to the connection terminal portion of the (k + 1) th unit conductive substrate by a wiring portion formed on a flexible printed wiring board (also referred to as FPC).
Specifically, the terminal portion for connection of the kth (k = 1 to (n−1)) unit conductive substrate forming the one separator member and the (k + 1) th unit conductivity forming the other separator member. The connection terminal portion of the substrate is electrically connected by a wiring portion formed on a flexible printed wiring board (also referred to as FPC), so that it can be used for a planar polymer electrolyte fuel cell. In addition, adjacent cells can be connected in series in order.
Such a connection terminal portion is prepared by, for example, surface plating such as gold plating after producing a unit conductive substrate having a plurality of through holes for fuel supply or oxygen supply. It is electrically connected to a flexible printed wiring board (also called FPC).
A flexible printed wiring board (also referred to as FPC) can be processed with high accuracy separately from each separator, and is advantageous in terms of production efficiency and processing accuracy. Also, instead of the conventional hinge part for connection, It can be set as the connection part which can connect easily.
In particular, by using a flexible printed wiring board as a connection, it can withstand repeated bending when manufacturing a PEFC.
More specifically, the fuel supply separator and the oxygen supply separator can be provided in the same manner and have compatibility with each other.
In this case, the fuel supply separator and the oxygen supply separator can be processed with the same design and can be used in different directions. This is advantageous in terms of production.

  The planar polymer electrolyte fuel cell of the present invention is a planar polymer electrolyte fuel cell in which unit cells are arranged in one direction in a planar manner by such a configuration. Instead of the connecting hinge part, a flat type with a connecting part that can be connected easily and easily without trouble, and that can withstand repeated bending when manufacturing a PEFC. It is possible to provide a polymer electrolyte fuel cell.

As described above, the present invention provides a pair of a fuel supply separator and an oxygen supply separator used in a planar polymer electrolyte fuel cell in which unit cells are planarly arranged in one direction. It can be formed into a fuel supply separator and an oxygen supply separator with a connection part that can be easily connected instead of a conventional connection hinge part, and without any effort. In addition, it is possible to provide a separator assembly including a connection portion that can withstand repeated bending when a PEFC is manufactured.
Furthermore, it has become possible to provide a separator assembly in which the fuel supply separator and the oxygen supply separator are compatible.
At the same time, it has become possible to provide a planar polymer electrolyte fuel cell using such a separator assembly.

Embodiments of the present invention will be described with reference to the drawings.
FIG. 1 shows an example of an embodiment of a separator assembly for a planar polymer electrolyte fuel cell according to the present invention, and FIG. 2 (a) is for oxygen supply in the embodiment shown in FIG. FIG. 2 (b) is a plan view of a separator for a fuel supply separator according to the embodiment shown in FIG. 1, and FIG. 3 (a) is a plan view from the A1 side of FIG. FIG. 3B is a cross-sectional view taken along the alternate long and short dash line B1-B2 in FIG. 3A showing how to connect the flexible wiring board. FIG. 4A shows another flexible wiring board. FIG. 4B is an enlarged detailed view of C1 in FIG. 4A, and FIGS. 5 and 6 are diagrams for explaining connection of a flexible wiring board and production of a separator. FIG.
In addition, the dotted line arrow in FIGS. 1-3 shows the direction of arrangement | sequence, The 1st-3rd has shown the order of the arrangement direction,
A dotted-line square region in FIG. 2 indicates the connection terminal portion 175 on the back surface side.
1 to 6, 110 is a separator assembly, 110A is a separator separator assembly without a flexible wiring board, 120 is a fuel supply separator, 121 is a separator member (of the fuel supply separator), 121A is a current collector, 121B Is a through hole, 121D is a gold plating part, 121a to 121c are unit conductive substrates, 122 and 123 are frame bodies (also referred to as insulating frame bodies), 123a is an opening, 124 is a gap part, 125 is a fitting part, 126 is Conductive member, 127 is a terminal electrode, 130 is an oxygen supply separator, 131 is a separator member (of the oxygen supply separator), 131A is a current collector, 131B is a through hole, 131D is a gold plating part, and 131a to 131c are Unit conductive substrates 132 and 133 are frames (also referred to as insulating frames), 133a is an opening, 134 is a gap, 13 Is a fitting portion, 137 is a terminal electrode, 140 is a membrane electrode assembly (MEA), 170 is a gold plating region (conductive corrosion resistance region), 175 and 176 are connection terminal portions (gold plating portion), and 180 is a flexible wiring board. (Also referred to as FPC), 181 is a wiring portion, and 182 is a base material portion.

First, an example of an embodiment of a separator assembly for a planar polymer electrolyte fuel cell according to the present invention will be described with reference to FIG.
The separator assembly 110 for a planar polymer electrolyte fuel cell in the example of this example is a fuel supply separator 120 used in a planar polymer electrolyte fuel cell in which unit cells are arranged in one direction in a plane. And an oxygen supply separator 130 as a pair.
The fuel supply separator 120 includes a separator member 121 (see FIG. 2B) in which three unit conductive substrates having a plurality of through holes for fuel supply are arranged in one plane in a plane via a gap. And a pair of insulating frames 122 and 124 that are integrated so as to sandwich the separator member 121, and the pair of insulating frames are arranged in the unit conductive substrates of the separator member 121, respectively. It has a predetermined opening corresponding to the position.
The oxygen supply separator 130 includes a separator member 131 (see FIG. 2A) in which three unit conductive substrates having a plurality of through holes for supplying oxygen are arranged in one direction in a plane via a gap. And a pair of insulating frames 132 and 134 that are integrated so as to sandwich the separator member 131, and the pair of insulating frames are arranged in the unit conductive substrate of the separator member 131, respectively. It has a predetermined opening corresponding to the position.

In this example, as shown in FIG. 2B, the separator member 121 of the fuel supply separator 120 is a unit conductive substrate 121a to 121c having a plurality of through holes 121B for fuel supply. The three conductive substrates 121a to 121c are arranged in one plane in a plane through the gap portion 124, and the first of the one end in the arranged direction among the three unit conductive substrates 121a to 121c. And the second unit conductive substrate 121a, 121b,
For the connection, the gold plating has a connection terminal portion 175 provided.
On the other hand, as shown in FIG. 2 (a), the separator member 131 of the oxygen supply separator 130 includes a plurality of through holes 131B for supplying oxygen as unit conductive substrates 131a to 131c. Three conductive substrates 131a to 131c are arranged in one direction in a plane via a gap 134, and correspond to the one side in the arranged direction among the three unit conductive substrates 131a to 131c. The second and third unit conductive substrates 131b and 131c at the end on the side to be connected have connection terminal portions 176 plated with gold for connection.
Note that the connection terminal portion 175 of the separator member 121 and the connection terminal portion 176 of the separator member 131 are both opposite to the membrane electrode assembly (MEA) side when used in a polymer electrolyte fuel cell. In FIG. 2 (a) and FIG. 2 (b), it is disposed on the back side.
Further, the connection terminal portions 175 of the first and second unit conductive substrates 121a and 121b forming the separator member 121 of the fuel supply separator 120 are respectively connected to the separator member 131 of the oxygen supply separator 130. Electrical connection is established by connection terminal portions 176 of the second and third unit conductive substrates to be formed and wiring portions 181 formed on the flexible printed wiring board 180.

The insulating frame 123 in the fuel supply separator 120 is on the membrane electrode assembly (MEA) side when used in a polymer electrolyte fuel cell, and the entire unit cell region is opened. On the other hand, the insulating frame 122 in the fuel supply separator 120 is on the side opposite to the membrane electrode assembly (MEA) side when used in a polymer electrolyte fuel cell. A plurality of through holes (not shown) are provided so as to open through holes (121B in FIG. 2) for allowing the fuel of the unit conductive substrate to pass therethrough.
The oxygen supply separator 130 is also basically the same as the fuel supply separator 120, and is an insulating frame 133 that becomes the membrane electrode assembly (MEA) side when used in a polymer electrolyte fuel cell. In contrast to the fact that the entire unit cell region is open, the insulating frame 132 that is the side opposite to the membrane electrode assembly (MEA) side when used in a polymer electrolyte fuel cell has its unit In the cell region, a plurality of through-hole portions (not shown) are provided so as to open through-holes (131B in FIG. 2) through which oxygen of the unit conductive substrate passes.
In this example, the frame body 122 and the frame body 132, and the frame body 123 and the frame body 133 are formed so as to have the same design when the directions are changed, respectively, for fuel supply. The separator 120 and the oxygen supply separator 130 can be interchanged by using different directions.

The insulating frame 122 of the separator member 121 and the insulating frame 132 of the separator member 131 are both opposite to the membrane electrode assembly (MEA) side when used in a polymer electrolyte fuel cell. In FIG. 3 (a), both are arranged on the back side.
And as shown in FIG.3 (b), each connection terminal part 175,176 area | region of the insulating frame bodies 122 and 132 is provided with a notch, and it fits the flexible wiring board 180 in the part. It has become.
1 corresponds to FIG. 3A, the shape of the B1-B2 cross section of FIG. 3A is FIG. 3B, and 125, 135 in FIG. 3B. Are the fitting portions.

Next, each part of the separator member 121 of the fuel supply separator 120 and the separator member 131 of the oxygen supply separator 130 will be briefly described.
The unit conductive substrates 121a to 121c and 131a to 131c may include a protective layer made of a corrosion-resistant (acid-resistant) and electrically conductive resin layer at least on the surface portion on the electrolyte side of the fuel cell.
In this example, the gold plating portion 170 corresponds to this, and a gold plating layer is provided as a protective layer.
Such a protective layer is not limited to this.
A method of forming a film by electrodeposition using a material in which a conductive material such as carbon particles and corrosion-resistant metal is mixed in a resin, and then heat-curing, or a resin made of a conductive polymer containing a dopant that increases conductivity A conductive and corrosion-resistant (acid-resistant) layer formed by a method of forming a state film by electrolytic polymerization or the like may be used.
Furthermore, a protective layer having acid resistance and electrical conductivity may be provided on a corrosion-resistant metal layer such as a gold plating layer.
Each of the unit conductive substrates 121a to 121c and 131a to 131c is processed into a predetermined shape by machining or etching using a photolithography technique. The unit conductive substrates 121a to 121c and 131a to 131c have through holes 121B for supplying fuel and through holes for supplying oxygen. The hole 131B is formed by these methods.

As the material of the insulating frames 122, 123, 132, and 133 constituting the fuel supply separator 120 and the oxygen supply separator 130, it is preferable to use an insulating material that has good workability, is light, and has high mechanical strength.
As such a material, a substrate material for a printed wiring board is used, and examples thereof include glass epoxy and polyimide.
The insulating frame having a desired shape can be formed by machining, laser processing, or the like.
The fuel supply side separator 120 and the oxygen supply side separator 130 may be manufactured by fixing the separator members 120a and 130a, which are individually manufactured, and the corresponding insulating frames while aligning them. .
The fixing of each member includes, for example, a method in which an adhesive such as an epoxy resin is applied and the adhesive is cured and fixed in a state where the members are overlapped.
The adhesive used in this case is not particularly limited as long as it does not affect other members in the manufacturing process and has excellent resistance to operating conditions when used in a fuel cell. .
Further, there is a method in which a part or all of the insulating frame is formed of a semi-cured prepreg, and is crimped to the separator members 121 and 131 to be fixed.

The fuel supply side separator 120 and the oxygen supply side separator 130 in the separator assembly 110 for the flat polymer electrolyte fuel cell of this example are flat as shown in FIGS. 6 (a) to 6 (b). The polymer electrolyte fuel cell can be manufactured as a planar polymer electrolyte fuel cell as shown in FIG.
The fuel supply side separator 120 and the oxygen supply side separator 130 are laminated with a membrane electrode assembly (MEA) 140 disposed therebetween to narrow the interval.
As described above, the membrane electrode assembly (MEA) 140 is a composite such as a current collector layer, a fuel electrode, a polymer electrolyte, an oxygen electrode, and a membrane in which a current collector layer is laminated. For example, as shown in FIGS. 7 and 8, the fuel electrode side catalyst layer 43 and the oxygen electrode side catalyst layer 44 are arranged on the membrane of the polymer electrolyte 41.
The connection terminal portions of the separator member 121 of the fuel supply separator 120 and the separator member 131 of the oxygen supply separator 130 that come out of the corresponding one unit conductive substrate and the other unit conductive substrate. The connecting terminal portions are electrically connected to each other by the flexible wiring board 180, whereby the three unit cells are electrically connected in series.
In this way, a planar polymer electrolyte fuel cell can be fabricated using the separator assembly 110 for the planar polymer electrolyte fuel cell of this example shown in FIG. As shown in (a), the flexible wiring board 180, the fuel cells 110A in which the separators 120 and 130 having no connection portion and the membrane electrode assembly (MEA) 140 are integrated are manufactured as separate bodies. It is possible to obtain a planar polymer electrolyte fuel cell by connecting with the flexible wiring board 180 after that. (FIGS. 5A to 5B)

The separator assembly for the planar polymer electrolyte fuel cell of the present example is one example, and the present invention is not limited to this.
For example, a mode in which the number of unit cell arrays is four or more is also included.
Moreover, the form made into the structure as shown to Fig.4 (a) which does not fit the flexible wiring board 180 in an insulating frame is also mentioned.
FIG. 4B is an enlarged view of the C1 portion of FIG.
Reference numeral 126 shown in FIG. 4B denotes a conductive member. For example, a structure filled with a conductive paste or solder can be given.
Of course, the Cu plating layer may be replaced with these.
Note that 121D is gold plating, but other conductive corrosion resistant films may be used instead.
In addition, in the separator assembly for the planar polymer electrolyte fuel cell of this example, the fuel supply separator and the oxygen supply separator are compatible so that they can be used in different directions. Non-structural forms are also included.
In addition, examples of the planar polymer electrolyte fuel cell of the present invention include those that do not use the separator assembly for the planar polymer electrolyte fuel cell of the present invention.

1 shows an example of an embodiment of a separator assembly for a planar polymer electrolyte fuel cell according to the present invention. 2A is a plan view of a separation member of the oxygen supply separator in the embodiment shown in FIG. 1, and FIG. 2B is a separation view of the fuel supply separator in the embodiment shown in FIG. It is a top view of a member. 3A is a plan view seen from the A1 side in FIG. 1, and FIG. 3B is a cross-sectional view taken along one-dot chain line B1-B2 in FIG. 3A showing how to connect the flexible wiring board. . FIG. 4A is a schematic sectional view showing another connection method of the flexible wiring board, and FIG. 4B is an enlarged detailed view of C1 in FIG. 4A. It is processing process sectional drawing for demonstrating the connection of a flexible wiring board, and preparation of a separator. It is processing process sectional drawing for demonstrating the connection of a flexible wiring board, and preparation of a separator. 1 is a cross-sectional view of an example of a planar PEFC (Polymer Electrolyte Fuel Cell). It is the figure which showed the state which spaced apart each member of planar type PEFC shown by FIG. It is a perspective view of the separator by the side of a fuel supply. FIG. 10 is a perspective view showing each part of FIG. 9 apart.

Explanation of symbols

110 Separator Assembly 110A Separator Separator Assembly without Flexible Wiring Board 120 Fuel Supply Separator 121 (Separator for Fuel Supply) Separator Member 121A Current Collector 121B Through Hole 121D Gold Plated Part 121a-121c Unit Conductive Substrate 122, 123 Frame Body (also called insulating frame)
123a opening 124 gap 125 fitting portion 126 conductive member 127 terminal electrode 130 separator for oxygen supply 131 separator member 131A (for separator for oxygen supply) current collecting portion 131B through hole 131D gold plating portions 131a to 131c unit conductive substrate 132 133 Frame (also called insulating frame)
133a Opening 134 Air gap part 135 Insertion part 137 Terminal electrode 140 Membrane electrode complex (MEA)
170 Gold plating area (conductive corrosion resistance area)
175, 176 Connection terminal (gold plated part)
180 Flexible wiring board (also called FPC)
181 Wiring part 182 Base material part 10 PEFC (Polymer electrolyte fuel cell)
10A Battery Main Body 20 Fuel Supply Side Separator 21 Conductive Substrates 21a-21c Unit Conductive Substrate 21A Current Collectors 22, 23 Frame (also referred to as insulating frame)
22a Through-hole 23a Opening 24 Cavity 27 Electrode terminal 30 Oxygen supply side separator 31 Conductive substrates 31a to 31c Unit conductive substrate 31A Current collectors 32 and 33 Frame (also referred to as insulating frame)
32a Through-hole 33a Opening 34 Gap 37 Electrode terminal 40 Membrane electrode assembly (MEA)
41 Solid polymer membrane (also referred to as polymer electrolyte) 43 Fuel electrode side catalyst layer 44 Oxygen electrode side catalyst layer 51, 52 Carbon paper 60 Case body 61 Fuel tank 62 Fuel supply port 70 Seal members 81, 82, 83 Unit cell 90 Fixing bolt

Claims (4)

  For a planar polymer electrolyte fuel cell having a pair of a fuel supply separator and an oxygen supply separator used in a planar polymer electrolyte fuel cell in which unit cells are arranged in one direction in a plane. The separator for supplying fuel and the separator for supplying oxygen are each configured such that a unit conductive substrate having a plurality of through holes for supplying fuel or supplying oxygen is planarly arranged through a gap. N separators (n is an integer of 2 or more) arranged in the direction, and a pair of insulating frames integrated so as to sandwich the separator members, the pair of insulating frames Each having a predetermined opening corresponding to the arrangement position of the unit conductive substrate of each separator member, and one separator portion of the fuel supply separator and the oxygen supply separator Among the n unit conductive substrates, the first to (n-1) th unit conductive substrates at one end in the arranged direction are connected to the direction side orthogonal to the arrangement direction. The other separator member has a terminal portion, and among the n unit conductive substrates, the second to nth unit conductive substrates at the end corresponding to the one side in the arranged direction Of the k-th (k = 1 to (n−1)) unit conductive substrate having a connection terminal portion on the direction side perpendicular to the arrangement direction and further forming the one separator member. The connection terminal portion and the connection terminal portion of the (k + 1) th unit conductive substrate forming the other separator member are electrically connected by a wiring portion formed on a flexible printed wiring board (also referred to as FPC). Planar polymer electrolysis characterized by being connected Separator set for the type of fuel cell.   The separator assembly for a planar polymer electrolyte fuel cell according to claim 1, wherein the fuel supply separator and the oxygen supply separator are made compatible with each other. A separator assembly for a planar polymer electrolyte fuel cell.   A planar polymer electrolyte fuel cell in which unit cells are arranged in a plane, comprising a fuel supply separator and an oxygen supply separator as a pair, the fuel supply separator and the oxygen supply separator One separator member is orthogonal to the arrangement direction from the first to (n-1) th unit conductive substrate at one end in the arrangement direction among the n unit conductive substrates. A terminal portion for connection is provided on the direction side, and the other separator member is the second to nth end of the n unit conductive substrates corresponding to the one side in the arranged direction. The unit conductive substrate has k terminal (k = 1 to (n−1)) having a connection terminal portion on the direction side orthogonal to the arrangement direction and further forming the one separator member. A terminal portion for connection of the unit conductive substrate and the other The connection terminal portion of the (k + 1) th unit conductive substrate forming the separator member is electrically connected by the wiring portion formed on the flexible printed wiring board (also referred to as FPC), and the n unit cells are A planar polymer electrolyte fuel cell characterized by being electrically connected in series. A flat polymer electrolyte fuel cell according to claim 3, wherein the separator assembly for a flat polymer electrolyte fuel cell according to claim 1 or 2 is used. A planar polymer electrolyte fuel cell.

Images