KR100726944B1 - Metallic net-structure current collector and monopolar-plate fuel cell pack with the same - Google Patents

Abstract

Provided is a net-structure metallic current collector, which enables subminiaturization of a fuel cell pack because cathodes and anodes of a fuel cell are arranged on one plane and covered with porous film. Current collectors face both sides of a membrane electrode assembly that generates electricity by air(oxygen) and fuel coming in and out through first and second cover members of a fuel cell pack, and collect electric currents. The net-structure metallic current collector(12) comprises first to fourth net-structure metallic current collector members(20,22,24,26) in which anodes(20a,22a,24a) and cathodes(22b,24b,26b) are coated with catalytic ink. An electrolytic membrane(28) is placed on the respective cathodes(22b,24b,26b) of the first to fourth net-structure metallic current collector members(20,22,24,26). The first to fourth net-structure metallic current collector members(20,22,24,26) are bended at the intermediate bend position(32). The bended structure is covered with porous film(30).

Description

METALLIC NET-STRUCTURE CURRENT COLLECTOR AND MONOPOLAR-PLATE FUEL CELL PACK WITH THE SAME}

1 is a schematic exploded view for explaining the structure of a typical fuel cell stack;

2 and 3 are views illustrating a mesh-type metal current collector according to a preferred embodiment of the present invention;

4 is a diagram illustrating a 6-cell fuel cell cell pack to which a cell connection method employing a mesh-type metal current collector according to the present invention shown in FIGS. 2 and 3 is applied.

* Explanation of symbols for main parts of drawings *

10A, 10B: first and second cover members,

12A, 12B, 12: Current Collector,

14A: air (oxygen) supply, 14B: fuel supply,

18A, 18B: Graphite plate,

18: Membrane Electrode Assembly (MEA),

20,22,24,26: first to fourth mesh type metal current collector members,

28: electrolyte membrane, 30: porous film.

The present invention relates to a mesh-type metal current collector and a single electrode fuel cell cell pack employing the current collector, and more particularly, can be suitably applied to a direct methanol fuel cell (DMFC) or a polymer fuel cell. The present invention relates to a mesh-type metal current collector and a single-electrode fuel cell cell pack using the current collector to realize an electrical connection structure of a cell using a mesh-type current collector.

Recently, research has been actively conducted on fuel cells which obtain electrical energy by chemical reaction of fuel.

Such a fuel cell is an environmentally friendly power generation system because it converts chemical energy of a fuel directly into electrical energy, and thus has high energy conversion efficiency and emits little pollutants causing environmental pollution.

As such fuel cells, direct methanol fuel cells (DMFCs) using methanol as fuel, polymer fuel cells, and the like are disclosed.

The DMFC generates electricity by the reaction of methanol as a fuel with oxygen as an oxidant, which results in significantly higher energy and power densities, eliminating the need for special peripherals (e.g., reformers), and the storage and supply of fuel. It is a power generator having the advantage of being easy.

1 shows a stack structure of a typical direct methanol fuel cell.

According to the fuel cell stack shown in the drawing, first and second cover members 10A and 10B as end plates for maintaining the physical shape of the corresponding fuel cell are provided, and the first and second 2 Current collectors 12A and 12B for collecting current are disposed on the inner surfaces of the cover members 10A and 10B.

The current collectors 12A and 12B are formed on both sides of the first and second flow path forming members (ie, graphite plates) on both sides of the MEA (Membrane Electrode Assembly) 18 which generates electricity by supplying methanol and air (oxygen) as fuel. It faces through 16A, 16B.

Here, the air (oxygen) injection portion 14A for injecting air (oxygen) and the fuel supply portion 14B for supplying fuel are provided on the first cover member 10A.

In addition, screwing is performed on the outer periphery of each component of the corresponding fuel cell cell pack at positions corresponding to the screw fastening holes 10a formed on the outer periphery of the first cover member 10A and the second cover member 10B. The ball is formed to be engaged by the screw.

The MEA 18 is formed by hot-pressing first and second carbon papers coated or coated with a catalyst ink on both sides of an electrolyte membrane, and the outer surfaces of the first and second carbon papers. The first and second flow path forming members 16A and 16B faced each other may be formed of, for example, 'carbon' having a flow path for supplying air and fuel so that air (ie, oxygen) and fuel are uniformly supplied to corresponding carbon paper. System plate '.

In this case, when a plurality of fuel cell cells are integrated in a corresponding fuel cell stack, each cell needs to be connected in series or in parallel, and thus, a component requiring flow paths must be formed of a conductive material. Or metal-based materials.

Further, in the fuel cell stack structure shown in FIG. 1, the first and second cover members 10A and 10B have a function for maintaining the shape of the corresponding fuel cell stack, for example, the first cover member. An air supply unit 14A for supplying air (oxygen) and a fuel supply unit 14B for supplying fuel are formed in 10A, and the second cover member 10B has air for discharging residual air / fuel. A fuel discharge portion (not shown) is formed.

Preferably, current collector sealing members 12a and 12b are installed inside the first and second current collectors 12A and 12B, and both sides of the MEA 18 may be installed. MEA sealing members 18A, 18B for sealing are provided, and such sealing structures are arranged when sealing for each component is required.

Here, in the fuel cell stack structure of FIG. 1, an additional component for introducing air (oxygen) for inducing a chemical reaction of the fuel is required, which makes it difficult to miniaturize the fuel cell.

In view of this, the single electrode method is considered for miniaturization of the fuel cell. However, the single electrode method requires a structure for properly connecting a plurality of cells on one surface.

Accordingly, the present invention has been made in view of the above-described prior art, and has a mesh-type metal in which a cell connection structure is formed by a mesh-type current collector directly coated and coated with a catalyst ink on the surface thereof, thereby making it possible to miniaturize the whole. The object is to provide a current collector and a fuel cell cell pack employing the current collector.

In order to achieve the above object, according to a preferred embodiment of the present invention on both sides of the air (oxygen) and the MEA (Membrane Electrode Assembly) generated by the fuel through the first and second cover members of the fuel cell pack. In the current collector faced to collect the current, the current collector comprises a first to fourth mesh type metal current collector member, the catalyst ink is coated / coated on the anode and the cathode, the first to fourth An electrolyte membrane is disposed on each cathode of the mesh-type metal current collector member, the intermediate bending position of the first to fourth mesh-type metal current collector members is bent, and is formed to cover the bent shape with a porous film. It is done.
The first mesh type current collector member is formed with a first anode and an anode electrode lead, and the second mesh type metal current collector member maintains a constant distance from the first anode of the first mesh type metal current collector member. A second anode and a first cathode integrally connected to the second anode and positioned to face the first anode of the first mesh type metal current collector member, wherein the third mesh type metal current collector The member is formed with a third anode at regular intervals from the second anode, and a second cathode positioned integrally connected to the third anode and positioned to face the second anode of the second mesh metal current collector member. The fourth mesh type metal current collector member includes a third cathode and a cathode electrode formed to face the third anode of the third mesh type metal current collector member. And a gong.

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Preferably, the porous film is sized for the selective supply of air and fuel to the anode and cathode of the first to fourth mesh type metal current collector members.

According to another embodiment of the present invention, a fuel supply unit having a porous first and second cover members, a fuel container formed therein and a fuel inlet for injecting fuel into the fuel container, and a catalyst ink coated / coated Each of the anode and the cathode is arranged on one surface of the first and second fuel cell consisting of the first to fourth mesh metal current collector member bent through the electrolyte membrane and covered by a porous film, wherein the first And the second fuel cell is disposed so that each cathode and the anode face the fuel from the fuel supply unit and the air (oxygen) passing through the first and second cover members.

The first mesh type current collector member is formed with a first anode and an anode electrode lead, and the second mesh type metal current collector member maintains a constant distance from the first anode of the first mesh type metal current collector member. A second anode and a first cathode integrally connected to the second anode and positioned to face the first anode of the first mesh type metal current collector member, wherein the third mesh type metal current collector The member is formed with a third anode at regular intervals from the second anode and a second cathode positioned integrally connected to the third anode and positioned to face the second anode of the second mesh metal current collector member. The fourth mesh type metal current collector member includes a third cathode and a cathode electrode formed to face the third anode of the third mesh type metal current collector member. And a gong.

Preferably, the porous film is sized for the selective supply of air and fuel.

Hereinafter, with reference to the accompanying drawings, the present invention will be described in detail.

2 and 3 are views for explaining a mesh-type metal current collector according to a preferred embodiment of the present invention.

According to the current collector 12 of the preferred embodiment of the present invention, a first anode A1 20a and an anode electrode lead 20b are formed in the first mesh type metal current collector member 20 and the second mesh type The metal current collector member 22 includes a second anode A2; 22a and a second anode that maintain a constant distance from the first anode A1; 20a of the first mesh type metal current collector member 20. A first cathode C1; 22b is formed integrally connected to A2; 22a and positioned to face the first anode A1; 20b of the first mesh-shaped metal current collector member 20.

In addition, according to the current collector 12, the third mesh type metal current collector member 24 includes a third anode A3; 24a and a third that maintain a constant distance from the second anode A2; 22a. A second cathode (C2; 24b) formed integrally connected to the anode (A3; 24a) and positioned to face the second anode (A2; 22a) of the second mesh type metal current collector member (22) is formed, The fourth mesh type metal current collector member 26 includes a third cathode C3; 26 a and a cathode electrode 26 b opposed to the third anode A3; 24 a of the third mesh type metal current collector member 24. ) Is formed.

Preferably, each anode (A1, A2, A3; 20a, 22a, 24a) and each cathode (C1, C2, C3; 22b) of the first to fourth mesh-type metal current collectors 20, 22, 24, and 26 Directly catalytic catalyst is applied and coated in the region of (24b, 26a).

In addition, as illustrated in FIG. 2, the cathodes C1, C2, C3; 22b, 24b of the second to fourth mesh type metal current collectors 22, 24, and 26 to which the catalyst ink is applied and coated, After the electrolyte membrane 28 is disposed on 26a), the intermediate bending positions (see '32' in FIG. 2) of the first to fourth mesh-type metal current collectors 20, 22, 24 and 26 are bent. The bent shape is covered by the porous film 30 (see FIG. 3).

Here, the porous film 30 serves to selectively supply oxygen and fuel in the air to the anodes A1, A2, A3 and the cathodes C1, C2, C3 according to the role of protecting the electrode and the pores. Will be

Therefore, in the structure of the mesh-shaped metal current collector 12 shown in FIGS. 2 and 3, each of the anodes A1, A2, A3 and cathodes C1, C2, C3 for contact with air (oxygen) or fuel is shown. Is placed on one face.

4 is a diagram illustrating a 6-cell fuel cell cell pack to which a cell connection method employing a mesh-type metal current collector according to the present invention shown in FIGS. 2 and 3 is applied.

That is, referring to the drawings, the first and second fuel cells 12-1 and 12-2 having the structures shown in FIGS. 2 and 3 are disposed at both sides of the fuel supply unit 30. A fuel cell 30a is formed inside the fuel cell 30, and a fuel injection hole 30b for injecting fuel into the fuel cell 30a is formed on one surface of the upper side of the fuel supply part 30.

In addition, first and second porous cover members 32A and 32B are disposed on the other side of the single-electrode fuel cells 12-1 and 12-2 to form a six-cell fuel cell cell pack.

Preferably, since the single-electrode fuel cells 12-1 and 12-2 are disposed to face the anode, the fuel supply unit 30 may be shared, thereby simplifying the structure.

On the other hand, the present invention is not limited to the above examples and various changes and modifications can be carried out within the scope not departing from the technical gist and gist of the invention.

As described above, according to the fuel cell cell pack employing the mesh type metal current collector and the current collector according to the present invention, the anode and the cathode of the fuel cell are disposed on one surface via one electrolyte membrane and covered by a porous film. As a result, the fuel cell cell pack can be miniaturized.

Moreover, adjusting the pore size of the porous film covering the anode and cathode forming a plurality of cells enables selective supply of oxygen and fuel in the air to the anode and cathode.

Claims (5)

In the current collector that collects the electric current facing both sides of the air (oxygen) and the MEA (Membrane Electrode Assembly) generated by the fuel through the first and second cover members of the fuel cell pack, The current collector includes a first to fourth mesh type metal current collector member having a catalyst ink coated / coated on the anode and the cathode, An electrolyte membrane is disposed on each cathode of the first to fourth mesh type metal current collector members, the intermediate bending position of the first to fourth mesh type metal current collector members is bent, and a porous film is formed on the bent shape. Mesh-type current collector, characterized in that formed to cover with. The method of claim 1, The first mesh type metal current collector member includes a first anode and an anode electrode lead, The second mesh type metal current collector member includes a second anode that maintains a constant distance from the first anode of the first mesh type metal current collector member, and is integrally connected to the second anode and is connected to the first mesh metal. A first cathode positioned so as to face the first anode of the current collector member, The third mesh type metal current collector member is opposite to the second anode of the second mesh type metal current collector member while being integrally connected to the third anode and the third anode maintaining a constant distance from the second anode. A second cathode is formed that is positioned to And the fourth mesh type metal current collector member comprises a third cathode and a cathode electrode formed to face the third anode of the third mesh type metal current collector member. The method of claim 1, The porous film is a mesh-type metal current collector, characterized in that formed in the size for the selective supply of air and fuel to the anode and the cathode of the first to fourth mesh-type metal current collector member. A porous first and second cover member, A fuel supply unit having a fuel container formed therein and having a fuel inlet for injecting fuel into the fuel container; First and second fuel cells comprising first to fourth mesh type metal current collector members which are bent through an electrolyte membrane and covered by a porous film so that each anode and cathode to which the catalyst ink is applied / coated is disposed on one surface. But with The first and second fuel cells are meshed metals arranged so that each cathode and anode face each other to face fuel (fuel) from the fuel supply unit and air (oxygen) passing through the first and second cover members. Fuel cell cell pack with current collector. The method of claim 4, wherein The first mesh type metal current collector member includes a first anode and an anode electrode lead, The second mesh type metal current collector member includes a second anode that maintains a constant distance from the first anode of the first mesh type metal current collector member, and is integrally connected to the second anode and is connected to the first mesh metal. A first cathode positioned so as to face the first anode of the current collector member, The third mesh type metal current collector member is opposite to the second anode of the second mesh type metal current collector member while being integrally connected to the third anode and the third anode maintaining a constant distance from the second anode. A second cathode is formed that is positioned to The fourth mesh type metal current collector member includes a mesh type metal current collector comprising a third cathode and a cathode electrode formed to face the third anode of the third mesh type metal current collector member. One fuel cell cell pack.

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