KR101181850B1 - Fuel cell system - Google Patents

Abstract

A fuel cell system according to the present invention includes a stack having an aggregate structure by a plurality of electricity generating units, a fuel supply source for supplying fuel to the electricity generating unit, an oxygen supply source for supplying oxygen to the electricity generating unit, and the electricity generation A refrigerant supply source for providing a cooling medium to the unit,

The stack is provided between the electricity generating units adjacent to each other to form a cooling passage through which the cooling medium passes, and the coolant supply source is arranged on the fuel injection unit and the oxygen injection unit side of the electricity generation unit.

Fuel Cell, Fuel Cell, Stack, Electricity Generator, Separator, Hydrogen Path, Oxygen Path, Common Flow Path, Air Supply Source, Refrigerant Supply Source, Oxygen Supply Source, Injection Section, Discharge Section, Temperature Deviation, Temperature Distribution

Description

Fuel Cell System {FUEL CELL SYSTEM}

1 is a block diagram schematically illustrating a configuration of a fuel cell system according to an exemplary embodiment of the present invention.

2 is an exploded perspective view showing the configuration of a stack for a fuel cell according to an embodiment of the present invention.

3 is a cross-sectional view of the coupling cross-sectional view of FIG.

4 is a block diagram schematically illustrating an overall configuration of a fuel cell system according to another exemplary embodiment of the present invention.

5 is an exploded perspective view showing the configuration of a stack for a fuel cell according to another embodiment of the present invention.

6 is a cross-sectional view of the coupling cross-sectional view of FIG.

7 is an exploded perspective view showing the configuration of a stack for a fuel cell according to another embodiment of the present invention.

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fuel cell system, and more particularly, to a fuel cell system having improved cooling structure of a fuel cell stack and a stack thereof.

As is known, a fuel cell is a power generation system that generates electrical energy through an electrochemical reaction of hydrogen and oxygen contained in a hydrocarbon-based fuel such as methanol, ethanol and natural gas.

Such a fuel cell has a stack that substantially generates electrical energy. The stack includes a membrane-electrode assembly (MEA) and a separator called bipolar plate in the art. It consists of a structure in which a unit cell consisting of a plurality of separators is arranged continuously. The stack is formed with respective inlets for injecting hydrogen and oxygen into the membrane-electrode assembly, and respective outlets for discharging the remaining hydrogen and oxygen after reacting in the membrane-electrode assembly.

The fuel cell stack configured as described above generates predetermined thermal energy through a reduction reaction of hydrogen and oxygen to the membrane-electrode assembly while generating electrical energy.

However, in the conventional fuel cell stack, the oxidation / reduction reaction of hydrogen and oxygen to the membrane-electrode assembly is more active at the injection side than at the discharge side of the stack due to the concentration difference, pressure difference, or hydrogen utilization rate of hydrogen and oxygen. In this case, a temperature deviation occurs at the inlet and outlet sides of the entire stack. Thus, the non-uniform temperature distribution of such a stack will cause degradation of the overall stack performance.

 SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and provides a fuel cell system having a structure that maximizes the heat exchange amount of a cooling medium and thermal energy to an injection portion of a stack.

In order to achieve the above object, a fuel cell system according to the present invention includes a separator disposed at both sides of a membrane-electrode assembly (MEA) and centering the membrane-electrode assembly. An electricity generation unit in which a plurality of flow passages of oxygen and a cooling medium are arranged on one surface of the one side separator in close contact with one surface, an air supply source for supplying oxygen and a cooling medium to the flow passage, and supplying fuel to the electricity generation unit Including a fuel source,

The electricity generating unit forms a fuel passage for distributing the fuel on one surface of the other side separator in close contact with the other surface of the membrane-electrode assembly, and each separator is formed at an injection portion side of the distribution passage. And a fuel injection portion of a manifold type for injecting the fuel into the fuel passage, wherein the air supply source is arranged on the fuel injection portion and the injection portion of the flow passage.

The fuel cell system according to the present invention preferably uses air supplied from the air supply as the oxygen and the cooling medium.

Further, in the fuel cell system according to the present invention, each separator may communicate with the fuel passage to form a fuel discharge portion for discharging the fuel passing through the fuel passage. In this case, in the fuel cell system according to the present invention, the fuel injection unit may be formed above the electricity generating unit, and the fuel discharge unit may be formed below.

In the fuel cell system according to the present invention, the flow path may be formed in a channel form on the contact surface of the separator in contact with the membrane-electrode assembly.

In addition, in the fuel cell system according to the present invention, the flow passage is formed along the opposite side end from one side end of the separator, and forms an air inlet for injecting air to the one end, and the air is provided on the opposite side end It is possible to form an air outlet for discharging. In this case, the fuel cell system according to the present invention may form the air inlet on the upper side of the electricity generating unit and the air outlet on the lower side.

In addition, the fuel cell system according to the present invention may be configured such that the air supply source is disposed above the electricity generating unit. The air source may include a fan for supplying air to the flow path.

In addition, the fuel cell system according to the present invention may be provided with a plurality of the electric generators to form a stack having an aggregate structure of these electric generators.

In addition, the fuel cell system according to the present invention for achieving the above object, the stack having an aggregate structure by a plurality of electricity generating unit, a fuel supply source for supplying fuel to the electricity generating unit, and oxygen to the electricity generating unit An oxygen supply source for supplying and a refrigerant supply source for providing a cooling medium to the electricity generation unit,

The stack is provided between the electricity generating units adjacent to each other to form a cooling passage through which the cooling medium passes, and the refrigerant supply source is arranged on the fuel injecting portion and the oxygen injecting portion of the electricity generating portion.

In addition, in the fuel cell system according to the present invention, the electricity generating unit comprises a separator (Separator) in close contact with both sides of the membrane-electrode assembly (MEA) in the center, the separator is The fuel injection unit for providing fuel to one surface of the membrane-electrode assembly may be formed, and the oxygen injection unit for providing oxygen to the other surface of the membrane-electrode assembly may be formed.

In the fuel cell system according to the present invention, the separator forms a fuel passage communicating with the fuel injection portion on a close contact surface in close contact with one surface of the membrane electrode assembly, and on the other surface of the membrane electrode assembly. An oxygen passage communicating with the oxygen injection unit may be formed on the close contact surface. In this case, the separator may form a fuel discharge part for discharging the fuel having passed through the fuel passage and an oxygen discharge part for discharging the oxygen having passed through the oxygen passage.

In the fuel cell system according to the present invention, the fuel injection unit and the oxygen injection unit may be formed above the electricity generation unit, and the fuel discharge unit and the oxygen discharge unit may be formed below. In this case, the fuel cell system according to the present invention is configured such that the refrigerant supply source is disposed above the electricity generating unit.

In the fuel cell system according to the present invention, it is preferable that the cooling passage is formed in a channel form on one surface of the separator and a contact surface of a neighboring separator that is in close contact with the separator so that the two channels are combined to form one hole.

In addition, the fuel cell system according to the present invention may include a cooling plate interposed between the electricity generating units adjacent to each other, and may form the cooling passage in the cooling plate.

In the fuel cell system according to the present invention, the refrigerant supply source may include a fan for supplying cooling air to the cooling passage.

In the fuel cell system according to the present invention, the fuel supply source may include a fuel pump for supplying the fuel to the fuel injection portion.

In the fuel cell system according to the present invention, the oxygen supply source may include an air pump for sucking air and supplying the air to the oxygen injection unit.

Moreover, it is preferable that the fuel cell system which concerns on this invention uses hydrogen gas as said fuel.

And the fuel cell system which concerns on this invention can also use the fuel which consists of the said liquid phase.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily implement the present invention. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein.                     

1 is a block diagram schematically illustrating a configuration of a fuel cell system according to an exemplary embodiment of the present invention.

The fuel cell system 100 according to the present invention will be described with reference to the drawings. The fuel cell system 100 reforms the fuel to generate hydrogen gas, and electrochemically reacts the hydrogen gas with the oxidant gas. A polymer electrolyte fuel cell (PEMFC) method that generates electrical energy is adopted.

In the fuel cell system 100, a fuel for generating electricity generally refers to a hydrogen gas generated by reforming the fuel, in addition to a gas containing hydrogen or a liquid fuel such as methanol, ethanol or natural gas. do. However, the fuel described below in the present embodiment means a fuel made of a liquid phase for convenience.

The system 100 may use oxygen gas stored in a separate storage means as an oxidant gas that reacts with hydrogen gas, and may use air containing oxygen. However, the latter example is explained below.

The fuel cell system 100 according to the present invention basically includes a plurality of electricity generating units 11 which generate electric energy through a reaction between hydrogen and oxygen, and generates hydrogen gas from the above-described fuel and generates hydrogen gas. And a fuel supply source 30 for supplying gas to the electricity generator 11, and an air supply source 50 for supplying air to the electricity generator 11.

The electricity generator 11 is connected to a fuel supply source 30 and an air supply source 50 to receive hydrogen gas from the fuel supply source 30 and to receive air from the air supply source 50 to receive the hydrogen gas. Hydrogen in the air and oxygen in the air are reacted electrochemically to form a fuel cell of a minimum unit generating electrical energy. Therefore, in the present exemplary embodiment, the plurality of electricity generating units 11 having the smallest unit as described above may be provided, and the stack 10 having the aggregate structure of the electricity generating units 11 may be formed by continuously arranging them.

In this embodiment, the stack 10 is powered by the air while performing an electrochemical reaction of hydrogen and oxygen through the hydrogen gas supplied from the fuel source 30 and the air supplied from the air source 50. It is structured to cool the heat which generate | occur | produces in the generating part 11. As shown in FIG.

The fuel supply source 30 includes a fuel tank 31 for storing liquid fuel, a fuel pump 33 connected to the fuel tank 31 to discharge fuel stored in the fuel tank 31, A reformer 35 disposed between the fuel tank 33 and the stack 10 to receive fuel from the fuel tank 33 to generate hydrogen gas from the fuel and to supply the hydrogen gas to the electricity generator 11. It includes. At this time, the reformer 35 may be connected to the fuel injection unit 13b of the electricity generating unit 11 which will be further described later through a pipeline.

In this fuel source 30, the reformer 35 preferably generates hydrogen gas from the above-described fuel through a catalytic reaction such as steam reforming, partial reforming or autothermal reaction by thermal energy. In addition, the reformer 35 may reduce the concentration of carbon monoxide contained in the hydrogen gas by, for example, a catalytic reaction such as a water gas conversion method, a selective oxidation method, or purification of hydrogen using a separator. Since the reformer 35 may be formed of a conventional PEMFC reformer configuration, detailed description thereof will be omitted herein.

The air supply source 50 is connected to the stack 10 and has at least one fan 51 that sucks air at a predetermined rotational force and supplies the air to the electricity generating unit 11. At this time, the fan 51 is preferably installed in a housing (17 in FIG. 3) surrounding the entire stack 10 to eject air to the entire stack 10.

Here, the system 100 according to the present invention is not equipped with a configuration for cooling the stack 10 in addition to the air source 50, which is part of the electricity supplied through the air source 50, the electricity generator ( This is because it is used for the electrochemical reaction of 11) and part is for stack cooling. This operation is possible by forming a distribution path (14a in FIG. 2) in the separator constituting the electricity generating unit 11, which will be described later.

Therefore, when hydrogen gas is supplied to the electricity generation unit 11 through the fuel supply source 30, and air is supplied to the electricity generation unit 11 through the air supply source 50, the electricity generation unit 11 generates the electricity. The heat is cooled by the air, and at the same time, the electricity generating unit 10 generates electric energy, water, and heat through an electrochemical reaction between hydrogen in hydrogen gas and oxygen contained in air.                     

Of course, when the fuel cell system 100 of the present invention is configured in a DMFC method of producing electricity by directly supplying a liquid fuel to a stack, unlike the above-described PEMFC method, a reformer is excluded. Hereinafter, the fuel cell system to which the reformer 35 is applied by the PEMFC method will be described as an example. However, the present invention is not necessarily limited thereto.

Meanwhile, with reference to the accompanying drawings, a stack 10 for generating electricity by receiving hydrogen gas and air from the fuel cell system 100 having the above-described structure and cooling the generated heat with the supplied air will be described with reference to the accompanying drawings. As follows.

FIG. 2 is an exploded perspective view showing the configuration of a stack for a fuel cell according to an embodiment of the present invention, and FIG.

Referring to the drawings, the stack 10 according to the present exemplary embodiment is formed by continuously arranging a plurality of electricity generating units 11 in close contact with each other, as described above. Each of the electricity generating units 11 is a film-electrode. Membrane Electrode Assembly (MEA) (hereinafter referred to as "MEA") 12 and a separator (bipolar plate in the art) which is placed in close contact with both sides of the MEA 12 as a center. And (15).

The MEA 12 has a structure in which an anode electrode is provided on one surface, a cathode electrode is provided on the other surface, and an electrolyte membrane is provided between two electrodes, having an active area of a predetermined area that causes an electrochemical reaction between hydrogen and oxygen. The anode electrode functions to oxidize hydrogen gas supplied from the reformer 35 to convert hydrogen into hydrogen ions (protons) and electrons. The cathode electrode functions to reduce and react the oxygen in the air supplied by the operation of the fan 51 with the hydrogen ions moved from the anode electrode, thereby generating heat and moisture at a predetermined temperature. The electrolyte membrane functions as an ion exchange to move hydrogen ions generated at the anode electrode to the cathode electrode.

The separator 15, which is arranged in close contact with both surfaces of the MEA 12, has a function of a conductor that connects the anode electrode and the cathode electrode of the MEA 12 in series, and the oxidation / measurement of the MEA 12 is performed. It also has a function of a passage for supplying hydrogen gas and air necessary for the reduction reaction to the anode electrode and the cathode electrode.

As mentioned above, a fuel passage 13a (hereinafter referred to as a 'hydrogen passage' for convenience) is formed on one surface of the separator 15 for supplying hydrogen gas for the oxidation / reduction reaction of the MEA 12. .

The heat generated by each of the electricity generating units 11 in the process of generating electricity by driving the stack 10 together with air necessary for the oxidation / reduction reaction of the MEA 12 on the opposite surface of the separator 15. A flow path 14a through which cooling air for cooling the air is supplied is formed.

Substantially, the separator 15 is a separator 14 having a hydrogen passage 13a configured to supply hydrogen gas to the other electricity generation unit 11 adjacent to the separator 14 having the flow passage 14a formed thereon to supply air ( 13) is formed by incorporating into contact with each other, and for convenience of understanding, in the following description, a separator to which hydrogen is supplied among the two separators that are in contact with each other to form a separator is referred to as a first separator 13 and a separator to which air is supplied is described. The second separator 14 is called.

To this end, in the drawing, a hydrogen passage 13a and a flow passage 14a are formed on one surface of the first separator 13 and the second separator 14, respectively, and a hydrogen passage 13a and a flow passage 14a are formed. Surfaces that are not in close contact with each other form a separator 15 well.

Here, the hydrogen passage 13a is formed by bringing the first separator 13 into close contact with the anode electrode surface of the MEA 12, so that the hydrogen separator 13a is in a straight line at an arbitrary distance from the contact surface of the first separator 13. It is formed in the form of a meander channel formed by alternately connecting both ends thereof.

Therefore, in order to form the stack 10 by continuously arranging a plurality of electricity generating units 11 including the separators 13 and 14 and the MEA 12 in succession, the second separator having the flow path 14a ( 14 immediately contacts the MEA 12, and the air supplied from the air supply source 50 passes through the flow passage 14a to cool the electricity generating unit 11 and is supplied to the cathode electrode of the MEA 12. Will be. Hydrogen gas generated from the reformer 35 of the fuel supply source 30 is supplied to the anode electrode of the MEA 12 through the hydrogen passage 13a of the first separator 13.

An embodiment of the flow path 14a of the second separator 14 will be described in more detail as follows.

The flow path 14a is formed at regular intervals in a channel form on the contact surface of the second separator 14 in contact with the MEA 12, and penetrates linearly from one end of the second separator 14 toward the opposite side. It has a formed structure.

This flow path 14a is in contact with the MEA 12 so that both ends communicate with the stack 10. Therefore, at one end of the flow passage 14a, an air inlet 14b for injecting air supplied from the air supply source 50 into the flow passage 14a is formed, and at the other end, for discharging the air. The air discharge part 14c is formed. At this time, the air inlet 14b is preferably formed above the second separator 14, and the air outlet 14c is preferably formed below the second separator 14.

Accordingly, the air supplied from the air source 50 flows along the flow path 14a through the air inlet 14b, and partly participates in the reduction reaction of the MEA 12, and the rest is the air outlet. The heat generated from the electricity generating unit 11 is radiated to the outside of the stack 10 while exiting through the 14c.

On the other hand, the first and second separators 13 and 14 are provided with a manifold type fuel injection unit 13b for injecting hydrogen gas into the hydrogen passage 13a of the first separator 13, and the hydrogen passage A fuel discharge portion 13c for discharging the remaining hydrogen gas after reacting with the MEA 12 while passing through 13a is formed. At this time, the fuel injection unit 13b formed in the first separator 13 is provided to communicate with the hydrogen passage 13a, and the fuel injection unit 13b formed in the second separator 14 is the hydrogen. It is provided so that it may communicate with the fuel injection part 13b of the 1st separator 13, without communicating with the channel | path 13a. In addition, the fuel discharge portion 13c formed in the first separator 13 is provided to communicate with the hydrogen passage 13a, and the fuel discharge portion 13c formed in the second separator 14 is a hydrogen passage. It is provided so that it may communicate with the fuel discharge part 13c of the 1st separator 13, without communicating with 13a.

In the present embodiment, the fuel injection unit 13b is formed on the air injection unit 14b side of the second separator 14, and the fuel discharge unit 13c is an air discharge unit (2) of the second separator 14. 14c) on the side. That is, the fuel injection unit 13b is formed above the separators 13 and 14 similarly to the air injection unit 14b of the second separator 14, and the fuel discharge unit 13c includes the second separator ( Like the air discharge | release part 14c of 14, it is formed below each separator 13 and 14. As shown in FIG.

In the operation of the fuel cell system 100 configured as described above, each of the electricity generating units 11 generates heat by a reduction reaction of hydrogen and oxygen, which heat is generated by hydrogen gas and air. The hydrogen gas and oxygen are supplied to the hydrogen passage 13a and the flow passage 14a of the separators 13 and 14 through the fuel injection portion 13b and the air injection portion 14b of the portion 11. The temperature varies depending on the position of the stack 10 due to a difference in concentration, a pressure difference, or hydrogen utilization. Specifically, oxidation of hydrogen and oxygen to the MEA 12 on the fuel inlet 13b and the air inlet 14b side of the stack 10 compared to the fuel outlet 13c and air outlet 14c sides. Since the reduction / reduction reaction is actively performed, a temperature deviation occurs on each of the injection portions 13b and 14b and the discharge portions 13c and 14c. This non-uniform temperature distribution of the stack 10 degrades the MEA performance of each electricity generating unit 11, thereby outputting an inconsistent voltage from each electricity generating unit (11).

Therefore, the fuel cell system 100 according to the present invention, as shown in Figure 3 to reduce the temperature variation of the stack 10 as described above, the fuel injection portion 13b and the air injection portion 14b of the stack 10 It is made of a structure that the air source 50 is disposed on the side.

Specifically, the fan 51 constituting the air supply source 50 is the upper side of the stack 10, that is, the fuel injection unit 13b and the air injection unit 14b side of the first and second separators 13 and 14. Is placed on.

Looking at the operation of the fuel cell system 100 according to the present invention configured as described above, the hydrogen gas generated from the reformer 35 is supplied to the anode electrode of the MEA 12 through the hydrogen passage (13a). During this process, the fan 51 is operated to supply air to the cathode electrode of the MEA 12 through the channel 14a. Then, the electricity generating unit 11 of the stack 10 generates heat by a reduction reaction of hydrogen and oxygen to the MEA 12.

In this process, part of the air flowing along the flow path 14a participates in the reduction reaction of the MEA 12, and the other part is generated in the electricity generating unit 11 while exiting through the air discharge unit 14c. The heat is radiated to the outside of the stack 10.

At this time, as the air supply source 50 according to the present embodiment is disposed on the upper side of the stack 10, that is, on the fuel injection unit 13c and the air injection unit 14c, the fuel injection unit for the entire stack 10 is provided. By maximizing the heat exchange rate per unit time for the heat energy and air generated in the (13c) and the air inlet (14c) side it is possible to uniformly maintain the temperature distribution of the overall stack (10).

4 is a block diagram schematically illustrating a configuration of a fuel cell system according to another exemplary embodiment of the present invention.

Referring to the drawings, the fuel cell system 200 according to the present embodiment, unlike the electric embodiment, supplies hydrogen gas and air to the stack 116 to generate electrical energy through an electrochemical reaction of hydrogen and oxygen. In addition, the heat generated by the stack 116 is cooled by the air supplied to the stack 116 separately.

To this end, the fuel cell system 200 is a fuel cell stack 116 that generates electrical energy through an electrochemical reaction between hydrogen and oxygen, and generates hydrogen gas from a liquid fuel and stacks the hydrogen gas. The fuel supply source 110 for supplying air to the stack 116, the oxygen supply source 112 for supplying air containing oxygen reacting with hydrogen in the hydrogen gas, and the cooling air to the stack 116. And a refrigerant source 114 for cooling the heat generated in the stack 116.

The stack 116 is connected to a fuel supply source 110 and an oxygen supply source 112 to receive the hydrogen gas from the fuel supply source 110 and to receive air from the oxygen supply source 112 to supply hydrogen in the hydrogen gas. And oxygen in the air to electrochemically react to generate electrical energy.

The fuel supply 110 includes a fuel tank 122 for storing liquid fuel, and a fuel pump 124 for discharging the fuel stored in the fuel tank 122 with a predetermined pumping force, as in the electric embodiment. And a reformer 118 that receives fuel from the fuel tank 122, generates hydrogen gas from the fuel, and supplies the hydrogen gas to the stack 116. In this case, the reformer 118 may be connected to the first injection unit 139a of the electricity generation unit 130 which will be further described later through a pipeline. Since the configuration of the fuel supply 110 is the same as that of the electric embodiment, detailed description thereof will be omitted.

In this embodiment, the oxygen source 112 includes an air pump 126 of conventional construction that sucks air with a predetermined pumping force and supplies this air to the stack 116. At this time, the air pump 126 may be connected to the second injection unit 139b of the electricity generating unit 130 which will be described later through the pipeline.

In addition, the coolant source 114 may be configured to easily take a cooling medium, that is, a natural state, and to supply cooling air having a lower temperature than the temperature inside the stack 116 to the stack 116 during operation.

Accordingly, the refrigerant source 114 includes a fan 128 that sucks air at a predetermined rotational force and supplies the air to the stack 116. At this time, the fan 128 is preferably installed in a housing (117 in FIG. 6) surrounding the entire stack 116 to eject air to the entire stack 116.

Embodiments constituting the stack 116 in the present invention will be described in detail with reference to the accompanying drawings.

5 is an exploded perspective view showing the configuration of a stack for a fuel cell according to another embodiment of the present invention, Figure 6 is a combined cross-sectional view of FIG.

Referring to the drawings, the stack 116 according to the present embodiment includes a plurality of electricity generating units 130 generating electrical energy by closely placing the separator 134 on both sides of the MEA 132. Thus, the electric generator 130 is composed of an aggregate structure.

In the present embodiment, the separator 134 is disposed in close contact with each other with the MEA 132 interposed therebetween to supply hydrogen gas and air to the anode electrode and the cathode electrode of the MEA 132. In this case, the separator 134 may be disposed such that the surface opposite to the surface in close contact with the MEA 132 is in close contact with the surface opposite the MEA 132 of the separator 134 of the neighboring electricity generating unit 130.

Each of the separators 134 includes a hydrogen passage 136 for supplying hydrogen gas to the anode electrode of the MEA 132 and an oxygen passage 138 for supplying air to the cathode electrode of the MEA 132. Doing. At this time, the hydrogen passage 136 is connected to the reformer 118 of the fuel source 110, the oxygen passage 138 is connected to the air pump 126 of the oxygen source 112.

Each separator 134 includes first and second injection units 139a and 139b of a manifold type for injecting hydrogen gas and air into the hydrogen passage 136 and the oxygen passage 138, and each passage ( Manifold type first and second discharge portions 139c and 139d for discharging the remaining hydrogen gas and air after reacting with the MEA 132 while passing through 136 and 138 are formed.

The first injection portion 139a is provided to communicate with the hydrogen passage 136 without being in communication with the oxygen passage 138, and the second injection portion 139b is provided without being in communication with the hydrogen passage 136. It is provided to communicate with the passage 138, the first discharge portion (139c) is provided to communicate with the hydrogen passage 136 without communicating with the oxygen passage 138, the second discharge portion (139d) It is provided to communicate with the oxygen passage 138 without being in communication with the hydrogen passage 136. In this case, the first and second injection parts 139a and 139b may be formed above the separator 134, and the first and second discharge parts 139c and 139d may be formed below the separator 134. .

The cooling air is circulated into the stack 116 to cool the heat generated by the electricity generating unit 130 when the stack 116 is configured as described above. Thus, the stack 116 is a coolant source 114. Cooling passages 141 are formed between the neighboring electricity generation unit 130 so that the cooling air supplied from the flow to the electricity generation unit 130.

In the present exemplary embodiment, the cooling passage 141 may be formed by the channels 141a respectively formed on the contact surfaces of the separators 134 which are in close contact with each other with respect to neighboring electricity generating units 130. At this time, the channel 141a is opposite to the surface of the separator 134 which is in close contact with the MEA 132 of the separator 134 and the neighboring electricity generator which is in close contact with the separator 134. The separator 134 may be formed on the contact surface of the 130. Therefore, the separator 134 of one electricity generating unit 130 and the separator 134 of the other electricity generating unit 130 adjacent to the electricity generating unit 130 are in close contact with each other in the form of facing each other. By combining the channel 141a, the cooling passage 141 according to the present exemplary embodiment may be formed.

In the stack 116 according to the present embodiment having the above structure, the cooling passage 141 is configured to inject cooling air through one end and to discharge the cooling air through the other end. That is, the cooling passage 141 forms a plurality of inlets 141b for injecting the cooling air into one edge side of the separator 134 in close contact with each other, and the other edge side corresponding to the edge side. A plurality of outlets 141c are formed in the outlet to discharge the cooling air. At this time, the inlet 141b is located at the first and second injection parts 139a and 139b of the separator 134, and the outlet 141c is located at the discharge parts 139c and 139d of the separator 134. It is preferable.

On the upper side of the stack 116, the coolant source 114 according to the present invention is disposed, the fan 128 constituting the coolant source 114 is the first, second injection portion (139a) of the separator 134 139b).

Looking at the operation of the fuel cell system 200 according to the present invention configured as described above, during the generation of electricity through the stack 116, the heat generating unit 130 by heat reduction by hydrogen and oxygen reduction reaction Will occur. At this time, the stack 116 is actively reacted with the oxidation / reduction of hydrogen and oxygen at the first and second injection parts 139a and 139b of the separator 134, so that the separator ( The temperature deviation occurs at the first and second injection parts 139a and 139b and the first and second discharge parts 139c and 139d of the 134.

In this state, when cooling air flows into the cooling passage 141 through the coolant source 114, the cooling air cools the heat while passing through the cooling passage 141.                     

At this time, as the refrigerant source 114 according to the present embodiment is disposed above the stack 116, that is, the first and second injection units 139a and 139b, the first and second injections of the entire stack 116 are performed. By maximizing the heat exchange rate per unit time with respect to air and heat energy generated from the side (139a, 139b) side it is possible to reduce the temperature deviation of the stack 116 as mentioned.

7 is an exploded perspective view showing the configuration of a stack for a fuel cell according to another embodiment of the present invention.

Referring to the drawings, the stack 116A according to the present embodiment is based on the same structure as in the previous embodiment, and the cooling plate 143 is provided between the separators 134A of the neighboring electricity generating units 130A. In addition, the cooling plate 143 has a structure in which a cooling passage 145 for circulating cooling air is formed.

The cooling plate 143 functions as a heat sink for dissipating heat transferred to the separator 134A when the electricity generation unit 130A generates electricity. The cooling plate 143 may be formed of aluminum, copper, iron, or the like having thermal conductivity.

Since the rest of the configuration and operation of the stack 116A according to the present embodiment is the same as the above embodiment, a detailed description thereof will be omitted.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, but, on the contrary, And it goes without saying that the invention belongs to the scope of the invention.

 As described above, according to the present invention, since an air source or a refrigerant source is provided on the fuel inlet / oxygen injector side of the stack, the cooling medium is distributed to the inside of the stack. The heat exchange amount of heat energy can be maximized. Thus, it is possible to maintain a uniform temperature distribution throughout the stack, further improving the cooling efficiency and performance of the entire stack.

Claims (23)

It comprises a separator disposed on both sides of the membrane-electrode assembly (MEA) center, the oxygen and the cooling medium flows jointly on one side of the separator in close contact with one surface of the membrane-electrode assembly An electricity generating unit in which a plurality of distribution paths are formed; An air supply source supplying oxygen and a cooling medium to the distribution passage; And A fuel supply source for supplying fuel to the electricity generating unit / RTI > The electricity generation unit forms a fuel passage for distributing the fuel on one surface of the other side separator in close contact with the other surface of the membrane electrode assembly, Each separator having a fuel injection portion of a manifold type which is formed on the injection portion side of the flow passage to inject the fuel into the fuel passage; And an air supply source opposed to the fuel injection portion and the injection portion of the flow passage so as to face the fuel injection portion and the injection portion side of the flow passage. The method of claim 1, And the oxygen and cooling medium are air supplied from the air source. The method of claim 1, Wherein each separator forms a fuel discharge portion in communication with the fuel passage for discharging fuel passing through the fuel passage. The method of claim 3, wherein And a fuel injector on the upper side of the electricity generator, and a fuel outlet on the lower side of the electricity generator. The method of claim 2, The flow path is formed in a channel form on the contact surface of the separator in contact with the membrane-electrode assembly. 6. The method of claim 5, The flow path is formed along one side end of the separator along the opposite side end, and forms an air inlet for injecting air to the one end, and forms an air outlet for discharging the air to the opposite side end. . The method of claim 6, And an air injector on an upper side of the electricity generator, and an air outlet on a lower side of the electricity generator. The method according to claim 4 or 7, And the air source is arranged above the electricity generating portion. 9. The method of claim 8, And the air source includes a fan for supplying air to the flow path. delete A stack having an aggregate structure by a plurality of electricity generating units; A fuel supply source for supplying fuel to the electricity generator; An oxygen supply source for supplying oxygen to the electricity generator; And Refrigerant supply source for providing a cooling medium to the electricity generating unit / RTI > The stack is provided between the electricity generating unit adjacent to each other to form a cooling passage for passing the cooling medium, And a fuel supply unit and the oxygen injection unit so as to directly face the fuel injection unit and the oxygen injection unit side of the electricity generating unit. The method of claim 11, wherein The electricity generating unit includes a separator disposed in close contact with both sides of a membrane-electrode assembly (MEA), And the separator forms the fuel injection portion for providing the fuel to one surface of the membrane-electrode assembly and the oxygen injection portion for providing oxygen to the other surface of the membrane-electrode assembly. 13. The method of claim 12, The separator forms a fuel passage communicating with the fuel injecting portion on an intimate surface in close contact with one surface of the membrane-electrode assembly, and communicating with the oxygen injecting portion in an intimate surface in close contact with the other surface of the membrane-electrode assembly. A fuel cell system forming an oxygen passage. The method of claim 13, The separator includes a fuel discharge portion for discharging fuel passing through the fuel passage and an oxygen discharge portion for discharging oxygen having passed through the oxygen passage. 15. The method of claim 14, And a fuel injector and an oxygen injector on the upper side of the electricity generator, and a fuel outlet and an oxygen outlet on the lower side. 16. The method of claim 15, And the refrigerant supply source is arranged above the electricity generating portion. 13. The method of claim 12, The cooling passage is formed in the form of a channel in the contact surface of the separator and the neighboring separator that is in close contact with the separator is a fuel cell system in which the two channels are combined to form one hole. The method of claim 11, wherein And a cooling plate interposed between the electricity generating units adjacent to each other, and forming the cooling passage in the cooling plate. 17. The method of claim 16, The coolant source includes a fan for supplying cooling air to the cooling passage. delete delete delete delete

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