KR101433933B1 - separator module and fuel cell stack comprising it - Google Patents

Abstract

A separator module according to an aspect of the present invention includes: a separator support; A fuel channel structure formed on one surface of the separator support body and having a fuel flow path; An oxidant channel structure formed on the other surface of the separator support body with an oxidant channel; A fuel inlet manifold through which the fuel fluid flows into the fuel flow path; A fuel outlet manifold through which the fuel fluid flows out from the fuel flow path; An oxidant inlet manifold through which the oxidant flows into the oxidant passage; Wherein the fuel inlet manifold or the oxidant inlet manifold or the fuel inlet manifold and the oxidant inlet manifold are arranged such that the surface to which the flow path is connected has a high center, And is formed in an obliquely protruding shape that becomes lower as it goes down.

Description

Separator module and fuel cell stack including the separator module

The present invention relates to a fuel cell stack and a separator module for a fuel cell stack, and more particularly, to a fuel cell stack and a separator module for a fuel cell stack that improve the structure of a reactant gas inlet manifold.

A fuel cell is a device that produces electricity electrochemically using fuel (hydrogen or reformed gas) and an oxidant (oxygen or air). The fuel and oxidizer continuously supplied from the outside are converted into electrical energy by electrochemical reaction .

As the oxidizer of the fuel cell, air containing a large amount of pure oxygen or oxygen is used. As the fuel, pure hydrogen, hydrocarbon-based fuel (LNG, LPG, CH3OH), or hydrocarbon- Use gas.

These fuel cells are mainly classified into a polymer electrolyte membrane fuel cell (PEMFC), a direct oxidation fuel cell, and a direct methanol fuel cell (DMFC). .

A polymer electrolyte fuel cell includes a fuel cell body called a stack, and generates electric energy through electrochemical reaction between hydrogen gas supplied from a reformer and air supplied by the operation of an air pump or a fan . Here, the reformer functions as a fuel processor that reforms the fuel to generate hydrogen gas from the fuel, and supplies the hydrogen gas to the stack.

Unlike a polymer electrolyte fuel cell, unlike a polymer electrolyte fuel cell, a direct oxidation type fuel cell receives an alcohol directly as a fuel without using hydrogen gas, and generates electricity by electrochemical reaction between hydrogen contained in the fuel and air supplied separately. As shown in Fig. A direct methanol type fuel cell refers to a cell that uses methanol as a fuel among direct oxidation type fuel cells.

Hereinafter, the polymer electrolyte fuel cell will be mainly described for convenience of explanation. The polymer electrolyte fuel cell has excellent output characteristics, low operating temperature, fast startup and response characteristics, and is suitable for use in a mobile power source such as an automobile, as well as a power source for dispersion and electronic devices And power supply for the same small device.

A membrane-electrode assembly used in a polymer electrolyte fuel cell comprises a catalyst layer mainly composed of a carbon powder carrying a metal catalyst such as a platinum group metal on both sides of a hydrogen-ion conductive polymer electrolyte membrane, and a membrane layer formed on the outer surface of the catalyst layer, And the gas diffusion layer is generally made of carbon paper or carbon nonwoven fabric.

The membrane electrode assembly is mechanically supported on the outer side of the membrane electrode assembly, and a separator having electrical conductivity for electrically connecting adjacent membrane electrode assemblies to each other is provided to form a unit cell. The separator supplies reactive gas to the electrode surface at a portion in contact with the membrane-electrode assembly, and forms a flow path for transporting surplus gas and reaction products. The flow path may be provided separately from the separator, but is generally formed in a groove on the surface of the separator.

A plurality of unit cells are stacked, and a collector plate for extracting a current and an insulation plate for insulation from the outside are sequentially stacked on the outermost side of the unit cell, and are fixed through a fastening plate and fastening means.

The fuel and the oxidant supplied to the fuel cell are converted into water through the electrochemical reaction in the membrane-electrode assembly and generate electricity and heat in this process. Unreacted fuel and oxidant are discharged to the outside of the fuel cell stack. The ratio of the reactor volume and the supply gas amount used in the electrochemical reaction is called the gas utilization rate.

A cooling unit in which the cooling medium flows for one or several unit cells is installed to discharge heat generated in the electrochemical reaction. The cooling unit includes a fuel separator having a fuel gas flow path on one side and a cooling flow path for cooling medium on the opposite side, an oxidant gas flow path having an oxidant gas flow path on one side and a cooling flow path for cooling medium on the opposite side, A method of attaching separators for use is often used.

In order to supply the reaction gas and the cooling medium from the outside of the fuel cell to the flow path of the separator and to discharge the excess gas, the reaction product and the cooling medium, at least two through holes are formed in the separator for each fuel gas, oxidant gas and cooling medium . The inlet and outlet of the flow path are connected to the respective through holes so that the reaction gas or the cooling medium is supplied to each flow path from one through hole and the excess gas and the reaction product or the cooling medium are discharged through the other through hole. The through holes for supplying the reaction gas and the cooling medium and for discharging the excess gas, the reaction product and the cooling medium are generally referred to as manifold holes.

In the manifold hole formed in the separator, a plurality of unit cells are stacked to form a stack, and a manifold is formed in a stacking direction. Such a reaction gas and a cooling medium supply method are referred to as an internal manifold method.

In addition to the internal manifold method, a system in which piping or a structure for gas distribution is formed outside the separator without forming a manifold hole in the separator, and a reaction gas or a cooling medium is supplied to each unit cell is referred to as an external manifold system.

In particular, a polymer electrolyte fuel cell is humidified to a certain level or higher when supplying reactive gases (fuel and oxidant) in order to improve the conductivity of hydrogen ions in the electrolyte membrane. On the other hand, since water is generated by the electrochemical reaction on the cathode side, when the dew point temperature of the reaction gas is higher than the fuel cell operating temperature, water droplets are generated due to condensation of water vapor in the gas flow path and the electrode.

This phenomenon is referred to as a flooding phenomenon. The flooding phenomenon causes a non-uniform flow of the reactant gas and a deficiency of the reactant gas in the electrode, thereby deteriorating the performance of the fuel cell. The flooding phenomenon may occur not only at the cathode electrode but also at the anode electrode by the water passed through the electrolyte membrane. Particularly, when the clogging of the gas flow path by the condensed water occurs on the anode side, it causes the deficiency of the fuel gas, which leads to the irreversible damage of the electrode.

This is because, when the load current is forcibly applied in the state where the fuel gas is insufficient, the carbon bearing the anode catalyst reacts with water in order to make electrons and protons without fuel. As a result of this reaction, the loss of the anode-side catalyst is caused and the effective electrode area is reduced, thereby deteriorating the performance of the fuel cell.

The condensed water entering the gas flow path obstructs the flow path and interferes with the flow of the reaction gas into the flow path, so that the fuel cell experiences a gas shortage phenomenon. In addition, condensation of water vapor, which is a reaction product, is further accelerated in a nearby electrode where condensed water is present, and flooding phenomenon is intensified.

A method has been used in which the flow rate of the supplied gas in the separator flow path portion is increased to discharge the condensed water in order to solve the clogging and flooding phenomenon of the gas flow path caused by the water introduced into the unit cell.

However, in order to increase the flow rate of the feed gas, it is necessary to supply the gas at a high pressure. To this end, the power of the gas supply blower or the compressor must be increased extremely.

Further, the condensed water is not uniformly distributed into all the unit cells but flows into the unit cells adjacent to the inlet side due to the nature of two-phase flow. In such a situation, the flow rate of the reactive gas is increased, There is a problem in that the water can not be efficiently discharged.

An object of the present invention is to provide a separator module and / or a fuel cell stack capable of suppressing the inflow of condensed water into the flow path.

Alternatively, the present invention intends to provide a separator module and / or a fuel cell stack capable of preventing deterioration of system efficiency.

A separator module according to an aspect of the present invention includes: a separator support; A fuel channel structure formed on one surface of the separator support body and having a fuel flow path; An oxidant channel structure formed on the other surface of the separator support body with an oxidant channel; A fuel inlet manifold through which the fuel fluid flows into the fuel flow path; A fuel outlet manifold through which the fuel fluid flows out from the fuel flow path; An oxidant inlet manifold through which the oxidant flows into the oxidant passage; And an oxidant outlet manifold through which the oxidant flows out from the oxidant passage,

The fuel inlet manifold or the oxidant inlet manifold or the fuel inlet manifold and the oxidant inlet manifold are formed in an obliquely protruding shape in which the surface to which the flow path is connected is centered and lowered toward the periphery.

Here, the inlet port and the inner wall of the channel inlet connected to the obliquely protruding surface can maintain a tilted angle, not perpendicular.

Here, the channel inlet connected to the surface formed in an inclined protruding shape may have a shape in which the cross section widens as it enters the inside. Alternatively, the flow path inlet connected to the surface formed in the inclined protruding shape may have a shape in which the cross section becomes narrower as it enters the inside.

Here, a plurality of flow inlets connected to the fuel flow path or the oxidant flow path may be disposed on the sloped surface, and the plurality of flow inlets may be inclined in the same direction.

Here, a plurality of flow inlets connected to the fuel flow path or the oxidant flow path are disposed on the sloped surface, and the plurality of flow path inlets may be inclined in symmetrical directions with respect to the center.

Here, in the separator support body, a cooling passage through which the cooling fluid flows can be formed.

According to another aspect of the present invention, there is provided a fuel cell stack including a plurality of electricity generating units including a membrane-electrode assembly (MEA) and a separator module closely disposed on both sides of the membrane- And an end plate provided on an outer periphery of the electricity generating units,

Wherein the reactant gas inlet manifold and the reactive gas outlet manifold are formed in the separator module, wherein the reactant gas inlet manifold and the reactive gas outlet manifold are formed in the electricity generating portion, And is communicated with the reaction gas flow path,

The reactant gas inlet manifold has a flow rate uniformly distributed by a flow guide, and a cross section of the reactant gas inlet manifold is inclined such that a surface to which the reactant gas flow passage is connected is inclined at a high center, And the opposite side may have the shape of a crescent moon or a pacman having an oval shape.

Here, the reactive gas may be a fuel gas or an oxidizing agent.

Here, the reactant gas inlet manifold may be located at the upper portion of the reactant gas outlet manifold with respect to the direction of gravity.

When the separator module and / or the fuel cell stack of the present invention according to the above-described configuration is implemented, there is an advantage that the condensed water can be prevented from flowing into the flow path.

Alternatively, the present invention has an advantage that it is possible to prevent deterioration of system efficiency.

1 is a cross-sectional view of a separator module according to an embodiment of the present invention;
FIG. 2 is a perspective view showing a stacked manifold duct structure in a fuel cell stack structure in which the separator modules and the membrane-electrode assemblies of FIG. 1 are alternately stacked. FIG.
FIG. 3A is a sectional view showing a connection structure of a fuel inlet manifold and a fuel flow path inlet of the separator module of FIG. 1; FIG.
FIG. 3B is a cross-sectional view illustrating a connection structure of an oxidant inlet port and an oxidant inlet port of the separator module of FIG. 1; FIG.
3C is a sectional view showing a connection structure of a fuel inlet manifold and a fuel flow path inlet of a separator module according to another embodiment.
FIG. 3D is a cross-sectional view showing a connection structure between an oxidant inlet port and an oxidant inlet port of a separator module according to another embodiment; FIG.
4A is a cross-sectional view showing a connection structure between a fuel inlet manifold and a fuel flow path inlet of a separator module according to another embodiment;
FIG. 4B is a cross-sectional view illustrating a connection structure between an oxidant inlet port and an oxidant inlet port of a separator module according to another embodiment of the present invention; FIG.
5 is a cross-sectional view showing a droplet generated by a flooding phenomenon in a flow path inlet in a manifold according to the prior art;
FIG. 6 is a cross-sectional view showing a droplet generated by a flooding phenomenon in a flow path inlet in a manifold according to an embodiment of the present invention; FIG.
FIG. 7 is a distribution diagram showing a simulation result of a flow velocity of a manifold according to the prior art; FIG.
8 is a distribution diagram that is a simulation result of a flow rate of a manifold according to the present invention.
9 is an exploded perspective view showing a fuel cell stack including a separator module according to an embodiment of the present invention.

Figure 1 illustrates a separator module 150 according to one embodiment of the present invention. In the separator module 150, a middle cooling channel is formed, and a fuel channel is formed on one surface and an oxidizer channel is formed on the other surface. In the drawing, only the cooling channels formed at the center are shown, Is omitted.

A separator module 150 according to an embodiment of the present invention shown in FIG. 1 includes a separator support body 123; A fuel channel structure formed on one surface of the separator support body 123 and having a fuel flow path; An oxidant channel structure formed on the other surface of the separator support body 123 with an oxidant channel; A fuel inlet manifold 143 into which the fuel fluid flows into the fuel flow path; A fuel outlet manifold 148 through which the fuel fluid flows out of the fuel flow path; An oxidant inlet manifold 141 through which the oxidant flows into the oxidant flow channel; And an oxidant outlet manifold 146 through which the oxidant flows out of the oxidant passage.

Here, the fuel inlet manifold 143 or the oxidant inlet manifold 141 or the fuel inlet manifold 143 and the oxidant inlet manifold 141 are arranged such that the center of the fuel inlet manifold 143 or the oxidant inlet manifold 141, It can be formed in an inclined protruding shape. The separator module 150 includes a coolant inlet manifold 142 for the coolant passage 145 and a coolant inlet manifold 142 for the coolant outlet manifold 142 147).

Figure 2 shows the fuel inlet manifolds 143 of the stacked separator modules 150 and the stacked membrane-electrode assemblies 140 in the fuel cell stack structure in which the separator modules 150 and membrane-electrode assemblies of Figure 1 are alternately stacked. And the cutouts at corresponding positions of the electrode assemblies are stacked to form a manifold duct structure.

In the manifold duct structure shown in the figure, the face (bottom face in the figure) where the fuel fluid flow paths of the separator modules are connected has an inclined protruding mountain shape having a high center and a lower periphery, It can be seen that the ceiling front in the figure is an ellipse or an arch. That is, the cross section connecting the bottom surface and the ceiling surface has a shape of a crescent moon or a pacman (an arcade game character of Namco).

As shown in the drawing, the flow guide / manifold structure having a cross section in the form of a crescent moon or a puckman causes a secondary flow caused by a wall effect inside the manifold to cause an internal flow change, There is an advantage that the development can be removed and the flow guide can be evenly distributed by the flow guide.

FIG. 3A is a cross-sectional view showing a connection structure between the fuel inlet manifold 143 and the fuel flow path inlet of the separator module 150 of FIG. 1, and FIG. 3B is a sectional view of the oxidant inlet manifold 141 of the separator module 150 of FIG. ) And the inlet port of the oxidant flow channel.

In the figures, the flow inlets connected to the fuel inlet manifold 143 of the separator module 150 of FIG. 1 and / or the surfaces LE, LE1 formed in the obliquely projected form of the oxidant inlet manifold 141, It can be seen that the inlet surface and the inner wall maintain a tilted angle, not perpendicular. That is, all of FIGS. 1 to 8 of FIGS. 3A and 11 to 20 of FIG. 3B have an angle of less than 90 degrees, and preferably an angle of 85 degrees or less.

Also, in the drawings, it can be seen that the channel inlet connected to the surfaces LE and LE1 formed in the slantingly projected form has a wider sectional shape as it enters the interior. That is, the width of d2 is larger than the width of d1 for all the flow inlets of Fig. 3A, which is the same also in the case of Fig. 3B.

In the drawings, a plurality of channel inlets connected to the fuel channel or the oxidant channel are disposed on the obliquely projected surfaces LE and LE1, and the plurality of channel inlets are inclined in the same direction .

3C is a cross-sectional view illustrating a connection structure between the fuel inlet manifold 143 and the fuel flow path inlet of the separator module 150 according to another embodiment. FIG. 3D is a cross-sectional view of the oxidant inlet manifold 141 ) And the inlet port of the oxidant flow channel.

Also in these figures, it can be seen that the flow inlets connected to the surfaces LE and LE formed in an obliquely protruding shape maintain their inclined angles, not perpendicular to the inlet and inner walls. That is, 1 'to 8' in FIG. 3C and 11 'to 20' in FIG. 3D all have angles less than 90 degrees, preferably less than 85 degrees.

In addition, in the above drawings, it can be seen that the channel inlet connected to the surfaces LE 'and LE1' formed in the slantingly protruding shape has a shape in which the cross section becomes narrower as it enters the inside. That is, the width of d2 'is smaller than the width of d1' for all the flow inlets of Fig. 3C, which is also the case in Fig.

In the drawings, a plurality of channel inlets connected to the fuel channel or the oxidant channel are disposed on the obliquely projected surfaces LE and LE1, and the plurality of channel inlets are inclined in the same direction .

4A is a cross-sectional view showing a connection structure of the fuel inlet manifold 243 and the fuel flow path inlet of the separator module according to yet another embodiment, and FIG. 4B is a cross-sectional view of the oxidant inlet manifold 241 ) And the inlet port of the oxidant flow channel.

In the drawings, a plurality of channel inlets connected to the fuel channel or the oxidizer channel are disposed on the obliquely projected surfaces LE2 and LE3, and the plurality of channel inlets are divided into a plurality of channels, As shown in FIG. The shape in which the flow inlets are inclined is different from that in Figs. 3A and 3B.

4A and 4B have a disadvantage in that they are difficult to manufacture as compared with the structures of FIGS. 3A and 3B. However, even if the surfaces LE2 and LE3 formed in an obliquely protruding shape have a higher inclination, The flow inlets connected to the surfaces LE, LE1 formed by the inlet and the outlet are advantageous in that the inlet and the inner wall can maintain a tilted angle rather than a perpendicular. That is, even if the slopes of LE2 and LE3 are high, the angles of f1 to f8 and f11 to f20 can be made smaller than 90 degrees. The angles may preferably have an angle of less than 85 degrees.

FIG. 5 is a cross-sectional view showing a droplet generated by a flooding phenomenon on a flow path inlet in a manifold according to the prior art, and FIG. 6 is a cross-sectional view of a droplet produced by a flooding phenomenon on a flow path inlet in a manifold according to an embodiment of the present invention And is a cross-sectional view showing a droplet.

In the case of the prior art shown in FIG. 5, the non-oblique inlet, that is, the vertical inlet having a constant width (d = d) has a phenomenon of droplet bridge do. On the other hand, in the case of the present invention shown in FIG. 6, a droplet is moved in the direction of gravity by an inclined angle &thetas; And the width of the lower inflow path of the wide width d2. According to the above-described principle, the droplet introduced into the inflow path is effectively removed to prevent flooding in the channel, thereby increasing the durability of the stack.

FIG. 7 is a distribution diagram showing a simulation result of a flow velocity of a manifold according to the prior art, and FIG. 8 is a distribution chart showing a simulation result of a flow rate of a manifold according to an embodiment of the present invention. Comparing the two distribution diagrams, it can be seen that the case of FIG. 8 has a more uniform flow / velocity distribution.

Depending on the implementation, the separator support 123 may not have an independent physical structure. For example, a fuel channel structure having a fuel channel disposed on the front surface, which is omitted from the drawing, is a single sheet having a fuel channel formed on the front surface and a half channel channel 145 formed on the rear surface, The oxidant channel structure in which the channel is formed is a single sheet in which a half channel channel 145 is formed on the entire surface and an oxidant channel is formed on the rear surface, and the two single sheets are bonded together to form the channel channel 145. In this case, the former sheet can be defined by the anode side separator, and the latter sheet can be defined by the cathode side separator. However, even in this case, a form in which the anode-side separator and the cathode-side separator are joined together to form the channel channel 145 can be regarded as the separator support body, although it is not an independent physical structure.

9 is an exploded perspective view illustrating a fuel cell stack including a separator module according to an embodiment of the present invention. In Fig. 9, the separator module is defined by the anode-side separator and the cathode-side separator.

The fuel cell stack 100 shown in FIG. 9 includes a membrane-electrode assembly (MEA) 131, and a plurality of electric cells (not shown) including a separator module disposed in close contact with the membrane- Generating units 130, and an end plate installed at an outer periphery of the electricity generating units.

The reactant gas inlet manifolds 141 and 143 and the reactant gas outlet manifold through which the reactant gas is discharged are formed in the electricity generating unit 130. The reactant gas inlet manifolds 141 and 143, And the reaction gas outlet manifold may communicate with the reaction gas flow path formed in the separator module.

Here, the cross section of the reactant gas inlet manifolds 141 and 143 has a crescent moon or a pacman shape in which the surface to which the reactant gas flow path is connected is inclined obliquely so as to have a high center, .

The fuel cell stack 100 shown in FIG. 9 includes an electricity generating unit 130 for generating electric energy by electrochemically reacting a fuel and an oxidant.

Each electricity generating unit 130 means a unit cell that generates electricity. The electricity generating unit 130 includes a membrane-electrode assembly (MEA) 131 for oxidizing / reducing oxygen in the fuel and the oxidizer, And a separator module 132, 133 for supplying the membrane-electrode assembly 131 to the membrane-electrode assembly 131.

A plurality of such electricity generation units 130 are provided and the electricity generation units 130 are continuously disposed to form the fuel cell stack 100 having the stacked structure of the electricity generation units 130.

The fuel cell stack 100 according to the present invention can use hydrogen cracked from liquid or gaseous fuel through a conventional reformer as fuel. In this case, the fuel cell stack 100 may be configured as a polymer electrolyte membrane fuel cell (Fuel Cell) system that generates electrical energy by the reaction of hydrogen and oxygen by the electricity generator 130.

Alternatively, the fuel used in the fuel cell stack 100 may include liquid or gaseous fuel containing hydrogen, such as methanol, ethanol, LPG, LNG, gasoline, butane gas and the like. In this case, the fuel cell stack 100 according to the present invention is a direct oxidation fuel cell system in which electric energy is generated through direct reaction of liquid or gaseous fuel with oxygen by the electricity generating unit 130 Lt; / RTI >

The fuel cell stack 100 may use pure oxygen stored in a separate storage means as an oxidant reacting with the fuel, and air containing oxygen may be used as it is.

The membrane-electrode assembly 131 includes a polymer electrolyte membrane formed of a solid polymer electrolyte and an anode electrode and a cathode electrode disposed on both sides of the polymer electrolyte membrane.

The separator modules 132 and 133 are disposed in close contact with each other with the membrane electrode assembly 131 interposed therebetween to form a fuel flow path 136 and an oxidant flow path 134 on both sides of the membrane electrode assembly 131. The anode separator 132 formed with the fuel flow path 136 is disposed on the anode electrode side of the membrane electrode assembly 131 and the cathode separator 133 formed with the oxidant flow path 134 is disposed on the anode electrode side of the membrane electrode assembly 131 And is disposed on the cathode electrode side. The electrolyte membrane moves the hydrogen ions generated in the anode electrode to the cathode electrode, thereby enabling ion exchange to combine with oxygen in the cathode electrode to generate water.

The plurality of electricity generators 130 are arranged continuously to constitute the fuel cell stack 100. An end plate 160 for fixing the fuel cell stack 100 integrally with the fuel cell stack 100 is installed at the outermost periphery of the fuel cell stack 100.

An oxidant injection port 162 for supplying an oxidant to the fuel cell stack 100 and a fuel injection port 164 for supplying fuel to the fuel cell stack 100 are formed on the upper end plate 160, A cooling medium inlet 163 for injecting is formed. In addition, a fuel outlet 167 for discharging the unreacted fuel reacted at the anode electrode and a moisture and unreacted air generated by the hydrogen-oxygen coupling reaction at the cathode electrode are discharged to the lower portion of the one end plate 160 An oxidant discharge port 169 for discharging the cooling medium, and a cooling medium discharge port 168 for discharging the cooling medium.

The anode / cathode separators 132 and 133 are formed with channel-shaped reaction gas flow passages 136 and 134 on one side thereof, and a reaction gas composed of fuel or oxidizing agent flows through the reaction gas flow passages 136 and 134 . Here, the reaction gas flow path is a concept including an oxidant flow path and a fuel gas flow path.

The cathode separator 133 has an oxidant channel 134 formed on one surface thereof facing the membrane electrode assembly 131 and an oxidant gas containing oxygen is introduced into the oxidant channel 134. The anode separator 132 has a fuel flow path 136 formed on one surface thereof facing the membrane electrode assembly 131, and a fuel gas containing hydrogen flows into the fuel flow path 136.

The anode / cathode separators 132 and 133 may have cooling passages formed on a rear surface opposite to the one surface, thereby eliminating reaction heat generated together with electrical energy.

Inside the fuel cell stack 100, an oxidant inlet manifold 141 through which an oxidant flows, a cooling medium inlet manifold 142 through which a cooling medium flows, and a fuel inlet manifold 143 through which fuel flows are formed . Inside the fuel cell stack 100, there are formed an oxidant outlet manifold 146 through which the oxidant is discharged, a fuel outlet manifold through which the fuel is discharged, and a cooling medium outlet manifold through which the cooling medium is discharged.

The oxidant inlet manifold 141 is formed at one upper corner of the fuel cell stack 100 and the oxidant outlet manifold 146 is formed at a diagonal corner of the one corner at the lower portion of the fuel cell stack 100 . In the present description, the upper part means that the upper part is based on the gravity direction, and the lower part means that the lower part is based on the gravity direction.

Further, the fuel inlet manifold 143 is formed at the other corner of the top of the fuel cell stack 100, and the fuel outlet manifold is formed at the diagonal corner of the other corner. The oxidant inlet manifold 141 and the fuel inlet manifold 143 are located at the top in the gravity direction relative to the oxidant outlet manifold 146 and the fuel outlet manifold.

The oxidant inlet manifold 141 and the fuel inlet manifold 143 are formed by holes formed in the electricity generating parts arranged in a laminated manner to form a duct structure.

The oxidant inlet manifold 141 and the oxidant outlet manifold 146 are in communication with the oxidant passage 134 formed in the cathode separator and the fuel inlet manifold 143 and the fuel outlet manifold are formed in the anode separator 132. [ And communicates with the fuel flow path 136.

The oxidant inlet manifold 141 and / or the fuel inlet manifold 143 have a cross section in the form of a crescent moon or a pacman, as shown in Fig. 2, according to the idea of the present invention. Accordingly, there is an advantage in that a secondary flow caused by the wall effect inside the manifold causes an internal flow change, thereby eliminating the bias of the reaction gas due to the gravity inside the manifold, and allowing the flow guide to be evenly distributed . Further, since the oblique-expanding inflow path shown in FIG. 6 is provided, it is possible to effectively remove the droplet introduced into the inflow path and to prevent flooding in the channel.

It is to be understood that the detailed description is only an example for the understanding of the present invention and should not be construed as being limited to the scope of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

100: Fuel cell stack
130: electricity generation unit
131: membrane-electrode assembly
132: anode separator
133: cathode separator
141: oxidant inlet manifold
143: fuel inlet manifold
150: Separator module

Claims (10)

A plurality of electricity generating units including a membrane-electrode assembly (MEA) and a separator module closely disposed on both sides of the membrane-electrode assembly, and an end plate installed at an outer periphery of the electricity generating units In addition,
Wherein the reactant gas inlet manifold and the reactive gas outlet manifold are formed in the separator module, wherein the reactant gas inlet manifold and the reactive gas outlet manifold are formed in the electricity generating portion, And is communicated with the reaction gas flow path,
The reactant gas inlet manifold is supplied with a flow rate evenly distributed by a flow guide,
Wherein a cross section of the reactant gas inlet manifold has a crescent moon or a pacman shape in which the surface to which the reactant gas flow path is connected is inclined obliquely so that the center thereof is high and decreases toward the periphery, .
The method according to claim 1,
The separator module includes: a separator support body; A fuel channel structure formed on one surface of the separator support body and having a fuel flow path; An oxidant channel structure formed on the other surface of the separator support body with an oxidant channel; A fuel inlet manifold through which the fuel fluid flows into the fuel flow path; A fuel outlet manifold through which the fuel fluid flows out from the fuel flow path; An oxidant inlet manifold through which the oxidant flows into the oxidant passage; And an oxidant outlet manifold through which the oxidant flows out from the oxidant passage,
Wherein the fuel inlet manifold or the oxidant inlet manifold or the fuel inlet manifold and the oxidant inlet manifold are formed in an obliquely protruding shape in which the surface to which the flow path is connected is centered and lowered toward the periphery, stack.
3. The method of claim 2,
Wherein the inlet port and the inner wall of the flow path inlet connected to the obliquely projecting surface maintain a tilted angle, not perpendicular.
The method of claim 3,
Wherein the channel inlet connected to the obliquely protruding surface has a shape in which a cross section is wider as it enters the inside.
The method of claim 3,
Wherein the flow path inlet connected to the surface formed in the slantingly protruding shape has a shape in which the cross section is narrowed as it enters the inside.
3. The method of claim 2,
On the surface formed in the inclined projecting shape,
A plurality of flow inlets connected to the fuel flow path or the oxidant flow path are disposed,
And the plurality of flow inlets are inclined in the same direction.
3. The method of claim 2,
On the surface formed in the inclined projecting shape,
A plurality of flow inlets connected to the fuel flow path or the oxidant flow path are disposed,
Wherein the plurality of the flow path inlets are inclined in a direction symmetrical to each other while being divided around the center.
3. The method of claim 2,
And a cooling flow passage through which the cooling fluid flows is formed in the separator support body.
The method according to claim 1,
Wherein the reactive gas is a fuel gas or an oxidant.
The method according to claim 1,
Wherein the reactant gas inlet manifold is located at an upper portion of the reactant gas outlet manifold relative to a direction of gravity.

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