KR20230032729A - Fuel cell stack - Google Patents

Abstract

An embodiment of the present invention relates to a fuel cell stack, comprising: a first unit cell including a plurality of first reaction cells electrically connected in parallel but independently capable of power generation; And a second unit cell including a plurality of second reaction cells electrically connected in parallel but provided to be independently capable of power generation, and stacked on the first unit cell to be electrically connected in series with the first unit cell. By doing so, it is possible to obtain advantageous effects of improving performance and operational efficiency.

Description

Fuel cell stack {FUEL CELL STACK}

The present invention relates to a fuel cell stack, and more particularly, to a fuel cell stack capable of increasing stability and durability, and improving performance and operational efficiency.

A fuel cell stack is a kind of power generation device that generates electrical energy through a chemical reaction of fuel (eg, hydrogen), and may be configured by stacking tens or hundreds of fuel cell cells (unit cells) in series.

A fuel cell is a Membrane Electrode Assembly (MEA) in which an electrolyte membrane capable of transporting hydrogen cations and electrodes (catalyst electrode layers) provided on both sides of the electrolyte membrane to allow hydrogen and oxygen to react are combined. It may include a gas diffusion layer (GDL) that adheres to both sides of the electrode assembly to evenly distribute reactive gases and transmits the generated electrical energy, and a bipolar plate that adheres to the gas diffusion layer and forms a flow path. there is.

Since the fuel cell stack has a characteristic of increasing output in proportion to an increase in the number of fuel cell cells (increase in reaction area), the output of the fuel cell stack can be increased by increasing the number of fuel cell cells.

However, when the number of fuel cell cells is increased in order to increase the output of the fuel cell stack, the voltage of the fuel cell stack also increases in proportion to the increase in the number of fuel cell cells, so as the output (voltage) of the fuel cell stack increases, A power converter suitable for high voltage must be provided.

On the other hand, if the voltage of the fuel cell stack is out of the proper range (eg, 0.5V to 0.85V), it causes deterioration of the fuel cell stack (membrane electrode assembly) and deteriorates stability and durability, so the fuel cell It should be possible to keep the voltage of the stack in an appropriate range.

However, in the past, regardless of the output condition of the fuel cell stack, tens or hundreds of fuel cell cells (unit cells) constituting the fuel cell stack must be used all the time (the entire reaction area is always used simultaneously) to generate power, so durability is In addition to being vulnerable, there is a problem in that it is difficult to maintain the voltage of the fuel cell stack in an appropriate range according to output conditions.

For example, in a low power operating condition of the fuel cell stack, each fuel cell is maintained at a high voltage (eg, 1V to 1.2V) as a low current is applied to each fuel cell. Conversely, in a high-output operating condition of the fuel cell stack, each fuel cell is maintained at a low voltage (eg, 0.4V to 0.6V) as a high current (eg, maximum current) is applied to each fuel cell. As such, when the voltage of the fuel cell stack changes to about 0.4V to 1.2V out of an appropriate range, there is a problem in that the fuel cell stack is deteriorated and durability is lowered.

Accordingly, in recent years, various studies have been conducted to improve the stability and durability of fuel cell stacks, and to improve performance and operational efficiency.

An object of the present invention is to provide a fuel cell stack capable of improving stability and durability, and improving performance and operational efficiency.

In particular, an object of an embodiment of the present invention is to selectively change a reaction area in which a reactive gas reacts in a fuel cell stack according to required conditions and use environments.

Above all, an object of the present invention is to partition one unit cell into a plurality of reaction cells electrically connected in parallel, and to allow each reaction cell to independently generate electricity.

In addition, an embodiment of the present invention can perform power generation under conditions that can minimize deterioration and durability of the fuel cell stack (a state in which the voltage is maintained in an appropriate range), and can minimize the use of a high voltage power conversion device. It aims to make

In addition, embodiments of the present invention are aimed at improving the output of a fuel cell stack and allowing the voltage of the fuel cell stack to be changed more diversely according to driving conditions (output).

In addition, an object of the present invention is to optimize the flow rate and pressure of a reactant gas per unit reaction area according to operating conditions, and to optimize the flow rate of cooling water.

In addition, embodiments of the present invention are aimed at extending the lifespan of a fuel cell stack.

The problem to be solved in the embodiment is not limited thereto, and it will be said that the solution to the problem described below or the purpose or effect that can be grasped from the embodiment is also included.

According to a preferred embodiment of the present invention for achieving the above-described objects of the present invention, a fuel cell stack includes a first unit cell including a plurality of first reaction cells electrically connected in parallel but independently capable of power generation. ; And a second unit cell including a plurality of second reaction cells electrically connected in parallel but provided to be independently capable of power generation, and stacked on the first unit cell to be electrically connected in series with the first unit cell. do.

This is to increase stability and durability of the fuel cell stack, and to improve performance and operational efficiency.

Conventionally, regardless of the output condition of the fuel cell stack, it is necessary to always use all of the tens or hundreds of fuel cell cells (unit cells) constituting the fuel cell stack (the entire reaction area is always used simultaneously) to generate power, which is vulnerable to durability. In addition, there is a problem in that it is difficult to maintain the voltage of the fuel cell stack in an appropriate range according to output conditions.

However, in an embodiment of the present invention, one unit cell is partitioned into a plurality of reaction cells electrically connected in parallel, and each reaction cell independently generates power, thereby reacting in a fuel cell stack according to the use environment. The reaction area in which the gas reacts can be selectively varied.

Therefore, power generation can be performed under conditions that can minimize deterioration and durability of the fuel cell stack (eg, a state in which the voltage is maintained in an appropriate range), thereby increasing stability and durability, and improving performance and operational efficiency. beneficial effects can be obtained.

According to a preferred embodiment of the present invention, the first unit cell includes a first membrane electrode assembly unit including a plurality of first divided membrane electrode assemblies independently divided to correspond to the plurality of first reaction cells; a first gas diffusion layer stacked on the first membrane electrode assembly unit so as to commonly cover the plurality of first split membrane electrode assemblies; and a first separator unit including a plurality of first partition separator plates stacked on the first gas diffusion layer to correspond to the plurality of first partition membrane electrode assemblies.

According to a preferred embodiment of the present invention, the second unit cell may include a second membrane electrode assembly unit including a plurality of second divided membrane electrode assemblies independently divided to correspond to the plurality of second reaction cells; a second gas diffusion layer stacked on the second membrane electrode assembly unit to commonly cover the plurality of second divided membrane electrode assemblies; and a second separator unit including a plurality of second partition separator plates stacked on the second gas diffusion layer to correspond to the plurality of second partition membrane electrode assemblies; can include

According to a preferred embodiment of the present invention, a first sealing member provided in the first membrane electrode assembly unit and independently partitioning the first divided membrane electrode assembly; a second sealing member provided in the first separation plate unit and independently partitioning the first division and separation plate; a third sealing member provided in the second membrane electrode assembly unit and independently partitioning the second divided membrane electrode assembly; and a fourth sealing member provided in the second separation plate unit and independently partitioning the second separation plate.

According to a preferred embodiment of the present invention, the first sealing member may include: a first edge sealing portion provided along an edge of the first membrane electrode assembly unit; and a first intermediate sealing part provided between the first partition electrode assemblies adjacent to each other and connected to the first edge sealing part, wherein the second sealing member is an edge of the first separator unit. A second edge sealing portion provided along; and a second intermediate sealing portion provided between the first split membrane electrode assemblies adjacent to each other and connected to the second edge sealing portion, wherein the third sealing member is a component of the second membrane electrode assembly unit. A third edge sealing portion provided along the edge; and a third intermediate sealing part provided between the second partition electrode assemblies adjacent to each other and connected to the third edge sealing part, wherein the fourth sealing member is an edge of the second separator unit. A fourth edge sealing portion provided along; and a fourth intermediate sealing part provided between the second divided film electrode assemblies adjacent to each other and connected to the fourth edge sealing part.

According to a preferred embodiment of the present invention, a first voltage monitoring terminal connected to at least one of the plurality of first dividing plates; and a second voltage monitoring terminal connected to at least one of the plurality of second dividing plates. can include

According to a preferred embodiment of the present invention, first manifold passages provided in each of the first dividing plates; second manifold passages provided on each of the second partitioning plates and communicating with the first manifold passage; and an opening/closing unit provided to be able to open and close the first manifold passage and the second manifold passage for each of the first division and separation plate and the second division and division plate; can include

According to a preferred embodiment of the present invention, a plurality of communication passages fastened to the outermost ends of the first unit cell and the second unit cell and communicating with the first manifold passage and the second manifold passage are formed. An end plate, wherein the opening/closing unit may include a plurality of opening/closing valves provided on the end plate to individually open and close the communication passages.

According to a preferred embodiment of the present invention, a plurality of communication passages fastened to the outermost ends of the first unit cell and the second unit cell and communicating with the first manifold passage and the second manifold passage are formed. end plate; and a manifold block provided at an end of the end plate and including a plurality of guide passages individually communicating with the communication passage, wherein the opening/closing unit is configured to individually open and close the guide passages. It may include a plurality of on-off valves provided in the fold block.

According to a preferred embodiment of the present invention, a plurality of first cooling water passages provided in the first separator unit and independently partitioned to correspond to the plurality of first partition separator plates; and a plurality of second cooling water passages provided in the second separation plate unit and independently partitioned to correspond to the plurality of second division separation plates.

According to a preferred embodiment of the present invention, the first unit cell may include a first membrane electrode assembly unit including a plurality of first divided membrane electrode assemblies independently divided to correspond to the plurality of first reaction cells; a first gas diffusion layer unit including a plurality of first divided gas diffusion layers stacked on the first membrane electrode assembly unit to correspond to the plurality of first divided membrane electrode assembly units; A first separation plate stacked on the first gas diffusion layer unit to commonly cover the plurality of first divided gas diffusion layers.

According to a preferred embodiment of the present invention, the second unit cell may include a second membrane electrode assembly unit including a plurality of second divided membrane electrode assemblies independently divided to correspond to the plurality of second reaction cells; a second gas diffusion layer unit including a plurality of second divided gas diffusion layers stacked on the second membrane electrode assembly unit to correspond to the plurality of second divided membrane electrode assembly units; A second separator stacked on the second gas diffusion layer unit so as to commonly cover the plurality of second divided gas diffusion layers.

According to a preferred embodiment of the present invention, a first sealing member provided in the first membrane electrode assembly unit and independently partitioning the first divided membrane electrode assembly; a second sealing member provided in the first gas diffusion layer unit and independently partitioning the first divided gas diffusion layer; a third sealing member provided in the second membrane electrode assembly unit and independently partitioning the second divided membrane electrode assembly; and a fourth sealing member provided in the second gas diffusion layer unit and independently partitioning the second divided gas diffusion layer.

According to a preferred embodiment of the present invention, a plurality of first manifold passages provided in the first separation plate to correspond to the first divided gas diffusion layer; a first partition member provided on the first separation plate and independently partitioning the first manifold flow path to correspond to the first divided gas diffusion layer; a plurality of second manifold passages provided in the second separation plate to correspond to the second divided gas diffusion layer; and a second partition member provided on the second separation plate and independently partitioning the second manifold passage to correspond to the second divided gas diffusion layer.

As described above, according to an embodiment of the present invention, advantageous effects of improving stability and durability, and improving performance and operating efficiency can be obtained.

In particular, according to an embodiment of the present invention, a reaction area in which a reactive gas reacts in a fuel cell stack may be selectively varied according to required conditions and use environments.

Above all, according to an embodiment of the present invention, one unit cell is partitioned into a plurality of reaction cells electrically connected in parallel, and each reaction cell independently generates electricity, thereby optimizing performance and operational efficiency. effect can be obtained.

In addition, according to an embodiment of the present invention, power generation can be performed under conditions that can minimize deterioration and durability of the fuel cell stack (a state in which the voltage is maintained in an appropriate range), and the use of a high voltage power conversion device is minimized. favorable effects can be obtained.

In addition, according to an embodiment of the present invention, the output of the fuel cell stack can be improved, and the voltage of the fuel cell stack can be changed more diversely according to driving conditions (output).

In addition, according to an embodiment of the present invention, it is possible to obtain advantageous effects of optimizing the flow rate and pressure of the reactant gas per unit reaction area according to operating conditions and optimizing the flow rate of cooling water.

In addition, according to an embodiment of the present invention, the life of a fuel cell stack can be extended.

1 is a diagram for explaining a fuel cell stack according to an embodiment of the present invention.
2 is a fuel cell stack according to an embodiment of the present invention, and is a diagram for explaining a first unit cell.
3 is a fuel cell stack according to an embodiment of the present invention, and is a diagram for explaining a second unit cell.
4 is a cross-sectional view for explaining a fuel cell stack according to an embodiment of the present invention.
5 is a diagram for explaining an electric circuit of a fuel cell stack according to an embodiment of the present invention.
6 is a fuel cell stack according to an embodiment of the present invention, a view for explaining an open/close unit.
7 is a fuel cell stack according to an embodiment of the present invention, a view for explaining a modified example of an open/close unit.
8 is a fuel cell stack according to an embodiment of the present invention, and is a diagram for explaining a cooling water flow path.
9 to 11 are views for explaining a fuel cell stack according to another embodiment of the present invention.

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

However, the technical idea of the present invention is not limited to some of the described embodiments and can be implemented in various different forms, and if it is within the scope of the technical idea of the present invention, one or more of the components among the embodiments can be selectively selected. can be used by combining and substituting.

In addition, terms (including technical and scientific terms) used in the embodiments of the present invention, unless explicitly specifically defined and described, can be generally understood by those of ordinary skill in the art to which the present invention belongs. It can be interpreted as meaning, and commonly used terms, such as terms defined in a dictionary, can be interpreted in consideration of contextual meanings of related technologies.

Also, terms used in the embodiments of the present invention are for describing the embodiments and are not intended to limit the present invention.

In this specification, the singular form may also include the plural form unless otherwise specified in the phrase, and when described as "at least one (or more than one) of A and (and) B and C", A, B, and C are combined. may include one or more of all possible combinations.

In addition, in describing the components of the embodiment of the present invention, terms such as first, second, A, B, (a), (b) may be used.

These terms are only used to distinguish the component from other components, and the term is not limited to the nature, sequence, or order of the corresponding component.

And, when a component is described as being 'connected', 'coupled' or 'connected' to another component, the component is not only directly connected to, coupled to, or connected to the other component, but also with the component. It may also include the case of being 'connected', 'combined', or 'connected' due to another component between the other components.

In addition, when it is described as being formed or disposed on the "top (above) or bottom (bottom)" of each component, the top (top) or bottom (bottom) is not only the case where two components are in direct contact with each other, but also one A case in which another component above is formed or disposed between the two components is also included. In addition, when expressed as "upper (above) or lower (down)", it may include not only an upward direction but also a downward direction based on one component.

1 to 9, a fuel cell stack 10 according to an embodiment of the present invention includes a plurality of first reaction cells 110 electrically connected in parallel but independently capable of power generation. 1 unit cell 100; and a plurality of second reaction cells 210 electrically connected in parallel but independently capable of power generation, and stacked on the first unit cell 100 to be electrically connected in series with the first unit cell 100. It includes; the second unit cell 200 to be.

For reference, the fuel cell stack 10 according to the embodiment of the present invention can be applied to various mobility such as vehicles, ships, and aviation, and the fuel cell stack 10 is applied to the target object (mobility). The present invention is not limited or limited by types and characteristics.

Hereinafter, an example in which the fuel cell stack 10 according to an embodiment of the present invention is applied to an eco-friendly vehicle such as a hybrid vehicle and/or an electric vehicle that obtains driving power with electric energy will be described.

For reference, in the fuel cell stack 10, after stacking a plurality of fuel cell cells (eg, a first unit cell and a second unit cell) in a reference direction (eg, a vertical direction), both ends ( It may be configured by fastening an end plate (see 300 in FIG. 7) to the outermost end).

Hereinafter, an example in which the fuel cell stack 10 includes the first unit cell 100 and the second unit cell 200 will be described. The stacked number of unit cells (fuel cell) may be variously changed according to required conditions and design specifications, and the present invention is not limited or limited by the stacked number of unit cells. According to another embodiment of the present invention, it is also possible to configure a fuel cell stack by stacking three or more unit cells.

Referring to FIGS. 2 and 4 , the first unit cell 100 constitutes one independently modularized fuel cell.

More specifically, the first unit cell 100 is configured by electrically connecting (modulating) a plurality of first reaction cells 110 capable of generating power independently in parallel.

Here, the first reaction cell 110 may be understood as a minimum fuel cell (minimum reaction area) capable of independently generating electricity.

The number of first reaction cells 110 constituting the first unit cell 100 may be variously changed according to required conditions and design specifications, and the present invention is limited by the number of first reaction cells 110. It is not limited or limited.

Hereinafter, an example in which the first unit cell 100 includes four reaction cells electrically connected in parallel will be described. Alternatively, the first unit cell may include 3 or less reaction cells or 5 or more reaction cells.

The first unit cell 100 may be provided in various structures including a plurality of first reaction cells 110 .

For example, the first unit cell 100 includes a first membrane electrode assembly unit 112 including a plurality of first divided membrane electrode assemblies 112a independently divided to correspond to the plurality of first reaction cells 110. ), the first gas diffusion layer 114 stacked on the first membrane electrode assembly unit 112 to commonly cover the plurality of first split film electrode assemblies 112a, and the plurality of first split film electrode assemblies 112a It may include a first separation plate unit 116 including a plurality of first division and separation plates 116a stacked on the first gas diffusion layer 114 to correspond to .

The first membrane electrode unit 112 includes a plurality of first divided membrane electrode assemblies 112a that are independently divided to correspond to the first reaction cell 110 .

Here, the independent division of the plurality of first divided film electrode assemblies 112a may be understood as electrically separating the plurality of first divided film electrode assemblies 112a from each other.

Hereinafter, an example in which four first divided film electrode assemblies 112a having a substantially rectangular shape are arranged on the same plane will be described.

The first split membrane electrode assembly 112a is provided to generate electricity through an oxidation-reduction reaction between a fuel (eg, hydrogen) as a first reaction gas and an oxidizing agent (eg, air) as a second reaction gas.

The structure and material of the first partition film electrode assembly 112a may be variously changed according to required conditions and design specifications, and the present invention is limited or limited by the structure and material of the first partition film electrode assembly 112a. it is not going to be

For example, the first split membrane electrode assembly 112a may be configured by attaching a catalyst electrode layer in which an electrochemical reaction occurs on both sides of an electrolyte membrane centered on an electrolyte membrane through which hydrogen ions move.

The plurality of first partitioned membrane electrode assemblies 112a may be divided in various ways according to required conditions and design specifications.

For example, the fuel cell stack 10 may include a first sealing member 310 provided in the first membrane electrode assembly unit 112 and independently partitioning the first divided membrane electrode assembly 112a, The plurality of first divided film electrode assemblies 112a may be independently divided through the first sealing member 310 .

More specifically, the first sealing member 310 includes the first edge sealing portion 312 provided along the edge of the first membrane electrode assembly unit 112 and the first split membrane electrode assembly 112a adjacent to each other. It may include a first intermediate sealing portion 314 provided between (boundary) and connected to the first edge sealing portion 312 .

The first sealing member 310 may be formed of an elastic material such as rubber, silicone, or urethane, and the present invention is not limited or limited by the material and characteristics of the first sealing member 310 .

The first gas diffusion layer 114 is formed on both sides of the first membrane electrode assembly unit 112 to evenly distribute reactive gases (hydrogen or air) and to transfer the generated electrical energy. are layered

The first gas diffusion layer 114 is composed of only one diffusion layer that can commonly (entirely) cover the plurality of first divided film electrode assemblies 112a.

The first gas diffusion layer 114 may be provided in various structures capable of diffusing a reactive gas. For example, the first gas diffusion layer 114 may have a porous structure having pores of a predetermined size.

The pore size and material of the first gas diffusion layer 114 may be variously changed according to required conditions and design specifications, and the present invention is not limited or limited by the pore size and material of the first gas diffusion layer 114. no.

The first separator unit 116 includes a plurality of first partition separator plates 116a stacked on the first gas diffusion layer 114 to correspond to the first partition electrode assembly 112a.

Hereinafter, an example in which four first divided separator plates 116a having a substantially rectangular shape are stacked on the first divided film electrode assembly 112a will be described.

The first partitioning plate 116a is provided to perform a role of securing an air flow path and transferring current to an external circuit in addition to a role of blocking hydrogen and air.

In addition, the first partitioning plate 116a also serves to distribute the heat generated in the first reaction cell 110 to the entire first reaction cell 110, and the excessively generated heat is removed from the first partitioning plate ( Cooling water moving along the cooling passage (see 117 in FIG. 8) of 116a) may be discharged to the outside.

In an embodiment of the present invention, the first partitioning plate 116a may be defined as including both an anode separator forming a flow path for hydrogen as a fuel and a cathode separator forming a flow path for air as an oxidizing agent. there is.

For example, the first partitioning plate 116a may be formed of thin metal (eg, stainless steel, inconel, or aluminum). The first divider plate 116a together with the first divider electrode assembly 112a forms one reaction cell and may independently form channels for hydrogen, air, and cooling water. According to another embodiment of the present invention, it is also possible to form the first divisional plate with other materials such as graphite or carbon composite material.

The plurality of first division/separation plates 116a may be divided in various ways according to required conditions and design specifications.

For example, the fuel cell stack 10 may include a second sealing member 320 provided on the first separation plate unit 116 and independently partitioning the first division separation plate 116a. The plurality of first division/separation plates 116a may be independently divided through the sealing member 320 .

More specifically, the second sealing member 320 is between the second edge sealing portion 322 provided along the edge of the first separator unit 116 and the first partition electrode assembly 112a adjacent to each other. It may include a second intermediate sealing portion 324 provided at (boundary) and connected to the second edge sealing portion 322 .

The second sealing member 320 may be formed of an elastic material such as rubber, silicone, or urethane, and the present invention is not limited or limited by the material and characteristics of the second sealing member 320 .

For reference, hydrogen as a fuel and air as an oxidizing agent pass through a channel (not shown) of the first partition separator 116a (cathode separator and anode separator) to the anode (not shown) of the first partition electrode assembly 112a. ) and a cathode (not shown), hydrogen may be supplied to the anode, and air may be supplied to the cathode.

Hydrogen supplied to the anode is decomposed into protons and electrons by the catalysts of the electrode layers provided on both sides of the electrolyte membrane, and only hydrogen ions are selectively transferred to the cathode through the electrolyte membrane, which is a cation exchange membrane. , At the same time, electrons are transferred to the cathode through the first gas diffusion layer 114 and the first partition plate 116a, which are conductors.

In the cathode, hydrogen ions supplied through the electrolyte membrane and electrons transferred through the first partition plate 116a meet with oxygen in the air supplied to the cathode by the air supply device to generate water. At this time, due to the movement of hydrogen ions, a flow of electrons occurs through the external conductor, and current is generated by the flow of these electrons.

Referring to FIGS. 3 and 4 , the second unit cell 200 constitutes one fuel cell module independently of the first unit cell 100 .

More specifically, the second unit cell 200 is configured by electrically connecting (modulating) a plurality of second reaction cells 210 capable of generating power independently in parallel.

Here, the second reaction cell 210 may be understood as a minimum fuel cell (minimum reaction area) capable of independently generating electricity.

The number of second reaction cells 210 constituting the second unit cell 200 may be variously changed according to required conditions and design specifications, and the present invention is limited by the number of second reaction cells 210. It is not limited or limited.

Hereinafter, an example in which the second unit cell 200 has the same structure as the first unit cell 100 will be described. According to another embodiment of the present invention, it is also possible to form the second unit cell and the first unit cell to have different structures.

For example, the second unit cell 200 may include four reaction cells electrically connected in parallel. Alternatively, the second unit cell may include 3 or less reaction cells or 5 or more reaction cells.

The second unit cell 200 may be provided in various structures including a plurality of second reaction cells 210 .

For example, the second unit cell 200 includes a second membrane electrode assembly unit 212 including a plurality of second divided membrane electrode assemblies 212a independently divided to correspond to the plurality of second reaction cells 210. ), the second gas diffusion layer 214 stacked on the second membrane electrode assembly unit 212 to commonly cover the plurality of second divided film electrode assemblies 212a, and the plurality of second divided film electrode assemblies 212a may include a second separation plate unit 216 including a plurality of second division and separation plates 216a stacked on the second gas diffusion layer 214 to correspond to .

The second membrane electrode unit 212 includes a plurality of second divided membrane electrode assemblies 212a that are independently divided to correspond to the second reaction cell 210 .

Here, the independent division of the plurality of second divided film electrode assemblies 212a may be understood as electrically separating the plurality of second divided film electrode assemblies 212a from each other.

Hereinafter, an example in which four second divided film electrode assemblies 212a having a substantially rectangular shape are arranged on the same plane will be described.

The second split membrane electrode assembly 212a is provided to generate electricity through an oxidation-reduction reaction between a fuel (eg, hydrogen) as a first reaction gas and an oxidizing agent (eg, air) as a second reaction gas.

The structure and material of the second partition film electrode assembly 212a may be variously changed according to required conditions and design specifications, and the present invention is limited or limited by the structure and material of the second partition film electrode assembly 212a. it is not going to be

For example, the second split membrane electrode assembly 212a may be configured by attaching catalyst electrode layers in which an electrochemical reaction occurs on both sides of an electrolyte membrane centered on an electrolyte membrane through which hydrogen ions move.

The plurality of second divided membrane electrode assemblies 212a may be divided in various ways according to required conditions and design specifications.

For example, the fuel cell stack 10 may include a third sealing member 330 provided in the second membrane electrode assembly unit 212 and independently partitioning the second divided membrane electrode assembly 212a, The plurality of second divided film electrode assemblies 212a may be independently divided through the third sealing member 330 .

More specifically, the third sealing member 330 includes the third edge sealing portion 332 provided along the edge of the second membrane electrode assembly unit 212 and the second divided membrane electrode assembly 212a adjacent to each other. It may include a third intermediate sealing portion 334 provided between (boundary) and connected to the third edge sealing portion 332 .

The third sealing member 330 may be formed of an elastic material such as rubber, silicone, or urethane, and the present invention is not limited or limited by the material and characteristics of the third sealing member 330 .

The second gas diffusion layer 214 is formed on both sides of the second membrane electrode assembly unit 212 to evenly distribute reactive gases (hydrogen or air) and to transfer the generated electrical energy. are layered

The second gas diffusion layer 214 is composed of only one diffusion layer that can commonly (entirely) cover the plurality of second divided film electrode assemblies 212a.

The second gas diffusion layer 214 may be provided in various structures capable of diffusing a reactive gas. For example, the second gas diffusion layer 214 may have a porous structure having pores of a predetermined size.

The pore size and material of the second gas diffusion layer 214 may be variously changed according to required conditions and design specifications, and the present invention is not limited or limited by the pore size and material of the second gas diffusion layer 214. no.

The second separator unit 216 includes a plurality of second partition separator plates 216a stacked on the second gas diffusion layer 214 to correspond to the second partition electrode assembly 212a.

Hereinafter, an example in which four second partition plates 216a having a substantially rectangular shape are stacked on the second partition electrode assembly 212a will be described.

The second partition plate 216a is provided to perform a role of securing an air flow path and transferring current to an external circuit in addition to a role of blocking hydrogen and air.

In addition, the second partitioning plate 216a also serves to distribute the heat generated in the second reaction cell 210 to the entire second reaction cell 210, and the excessively generated heat is removed from the second partitioning plate ( Cooling water moving along the cooling passage (see 217 in FIG. 8) of 216a) may be discharged to the outside.

In an embodiment of the present invention, the second partition plate 216a may be defined as including both an anode separator plate forming a flow path of hydrogen as a fuel and a cathode separator plate forming a flow path of air as an oxidant. there is.

For example, the second partitioning plate 216a may be formed of thin metal (eg, stainless steel, inconel, or aluminum). The second divider plate 216a together with the second divider electrode assembly 212a forms one reaction cell, and may independently form flow paths for hydrogen, air, and cooling water. According to another embodiment of the present invention, it is also possible to form the second partition plate with other materials such as graphite or carbon composite material.

The plurality of second division plates 216a may be divided in various ways according to required conditions and design specifications.

For example, the fuel cell stack 10 may include a fourth sealing member 340 provided on the second separator unit 216 and independently partitioning the second partition plate 216a. The plurality of second division/separation plates 216a may be independently divided through the sealing member 340 .

More specifically, the fourth sealing member 340 is between the fourth edge sealing portion 342 provided along the edge of the second separation plate unit 216 and the second partitioning plate 216a adjacent to each other ( boundary) and may include a fourth intermediate sealing portion 344 connected to the fourth edge sealing portion 342 .

The fourth sealing member 340 may be formed of an elastic material such as rubber, silicone, or urethane, and the present invention is not limited or limited by the material and characteristics of the fourth sealing member 340 .

For reference, hydrogen as a fuel and air as an oxidizing agent pass through a channel (not shown) of the second partition separator 216a (cathode separator and anode separator) to the anode (not shown) of the second partition electrode assembly 212a. ) and a cathode (not shown), hydrogen may be supplied to the anode, and air may be supplied to the cathode.

Hydrogen supplied to the anode is decomposed into protons and electrons by the catalysts of the electrode layers provided on both sides of the electrolyte membrane, and only hydrogen ions are selectively transferred to the cathode through the electrolyte membrane, which is a cation exchange membrane. , At the same time, electrons are transferred to the cathode through the second gas diffusion layer 214 and the second partition plate 216a, which are conductors.

In the cathode, hydrogen ions supplied through the electrolyte membrane and electrons transferred through the second partition plate 216a meet with oxygen in the air supplied to the cathode by the air supply device to generate water. At this time, due to the movement of hydrogen ions, a flow of electrons occurs through the external conductor, and current is generated by the flow of these electrons.

According to a preferred embodiment of the present invention, the fuel cell stack 10 includes a first voltage monitoring terminal 410 connected to at least one of a plurality of first dividing plates 116a, and a plurality of second dividing plates 116a. A second voltage monitoring terminal 420 connected to at least one of the plates 216a may be included.

The first voltage monitoring terminal 410 is provided to monitor the voltage of the first partitioning plate 116a partitioned for each first reaction cell 110, and the second voltage monitoring terminal 420 is provided to monitor the voltage of the second reaction cell. It is provided to monitor the voltage of the second partition plate 216a partitioned by 210.

For example, the first voltage monitoring terminal 410 may be individually connected to the plurality of first dividing plates 116a, and the second voltage monitoring terminal 420 may be connected to the plurality of second dividing plates 216a. Each can be connected individually.

As such, in the embodiment of the present invention, a plurality of unit cells (first unit cell and second unit cell) are electrically connected in series, but each unit cell (first unit cell and second unit cell) is electrically By including a plurality of reaction cells (first reaction cell and second reaction cell) partitioned to be connected in parallel, the number of reaction cells in which actual power generation (electrochemical reaction) is performed increases or decreases (reactions It is possible to adjust the output of the fuel cell stack 10 by varying the area.

Referring to FIG. 5 , partial power generation of the fuel cell stack 10 is performed through a plurality of first reaction cells 110 and a second reaction through distribution of a current collector plate (not shown) and reactive gas of the fuel cell stack 10 . This may be done by controlling which of the cells 210 generate current.

At this time, since the plurality of first reaction cells 110 and second reaction cells 210 are electrically connected in parallel, the voltages V _cell of each reaction cell (first reaction cell and second reaction cell) are mutually The same (V1 = V2 = V3 = V4), and the current (A _cell ) may increase or decrease (eg, A _cell = A1 + A2 + A3 + A4) according to the number of reaction cells in which power generation is actually performed, The output (W _cell =V _{cell Х} A _cell ) of the fuel cell stack 10 may be determined based on the voltage (V _cell ) and current (A _cell ) of each reaction cell. For reference, the total voltage (V _total ) of the fuel cell stack 10 is determined by the sum of the voltages of each reaction cell (V _cell1 +V _cell2 + ... +V _celln =V _total ), and the fuel cell stack ( The total current (A) of 10) is determined to be equal to the current value of each reaction cell (A _cell1 = A _cell2 = ... = A _celln =A).

For example, when low power of the fuel cell stack 10 is required, since only a part of the plurality of first reaction cells 110 and second reaction cells 210 are used for actual power generation (partial power generation), The current density of the reaction cell in which power generation takes place can be kept relatively high.

For example, when only 0.4W is output from a unit cell (first unit cell and second unit cell) with a maximum output of 1.6W, response area control through partial power generation of unit cell (first unit cell and second unit cell) Since the current density of the reaction region (reaction cell) where actual power generation is performed can be maintained high by adjusting the current density, it is not necessary to apply a high voltage to the fuel cell stack 10 during low power operation of the fuel cell stack 10. .

In this way, it is possible to suppress the application of high voltage to the fuel cell stack 10 during low-output operation of the fuel cell stack 10, thereby suppressing deterioration of the fuel cell stack 10 due to application of the high voltage and improving durability. beneficial effects can be obtained.

On the other hand, when high output of the fuel cell stack 10 is required, the partial power generation area of the fuel cell stack 10 is expanded to the entire area (eg, all reaction cells) (the number of reaction cells in which power is actually generated). By increasing ), it is possible to increase the current of each unit cell in a state where the voltage is kept constant, thereby increasing the overall output of the fuel cell stack 10 .

In addition, when a change in the required output of the fuel cell system is required, the voltage applied to each reaction cell is changed by changing the partial power generation area of the fuel cell stack 10 (the number of reaction cells in which power is actually generated). Since it is possible to respond to the required output (required output) by narrowing the range of and increasing or decreasing the current generated by each reaction cell, the condition (maintaining the voltage in an appropriate range) to minimize deterioration and durability of the fuel cell stack 10 state), and the use of a high-voltage power conversion device can be eliminated.

Referring to FIGS. 2, 3, and 6, according to a preferred embodiment of the present invention, the fuel cell stack 10 includes first manifold passages 118 provided on the first split plate 116a, respectively; The second manifold flow passage 218, which is provided on the second dividing plate 216a and communicates with the first manifold passage 118, and the first dividing plate 116a and the second dividing plate 216a It may include an opening/closing unit 500 provided to open and close the first manifold passage 118 and the second manifold passage 218 separately.

For example, the first manifold passage 118 may be formed at each end of the plurality of first dividing plates 116a, and each first reaction cell 110 via the first manifold passage 118 A reactive gas (hydrogen or air) may be supplied.

The second manifold passage 218 may be formed at each end of the plurality of second dividing plates 216a, and the reaction gas ( hydrogen or air) may be supplied.

The opening/closing unit 500 is provided to individually open and close the first manifold passage 118 and the second manifold passage 218 for each of the first division plate 116a and the second division division plate 216a.

Here, opening and closing the first manifold passage 118 and the second manifold passage 218 means the flow of the reaction gas flowing through the first manifold passage 118 and the second manifold passage 218. It is defined as including everything that regulates (on / off) or controls the flow rate of the reaction gas.

The opening/closing unit 500 may be provided in various structures capable of individually opening and closing the first manifold flow path 118 and the second manifold flow path 218, and the present invention is based on the type and structure of the open/close unit 500. It is not limited or restricted.

For example, referring to FIG. 6 , according to a preferred embodiment of the present invention, the fuel cell stack 10 is fastened to the outermost ends of the first unit cell 100 and the second unit cell 200, An end plate 300 having a plurality of communication passages 302 communicating with the first manifold passage 118 and the second manifold passage 218 is formed. It may include a plurality of on/off valves 510 provided on the end plate 300 to be individually open and close.

As the on-off valve 510, a conventional valve capable of selectively opening and closing the communication passage 302 may be used, and the present invention is not limited or limited by the type and structure of the on-off valve 510. For example, a conventional solenoid valve may be used as the opening/closing valve 510 .

In this way, by individually opening and closing the plurality of communication passages 302 communicating with the first manifold passage 118 and the second manifold passage 218 by the opening/closing valve 510, the fuel cell stack ( In the case of partial power generation in 10), it is possible to supply (or control the flow rate of the reaction gas) only the reaction cells among the plurality of first reaction cells 110 and second reaction cells 210 where power is actually generated.

Moreover, the reaction gas is supplied to the fuel cell stack 10 at a flow rate that can be supplied to all reaction cells (first reaction cell and second reaction cell), and actual power generation occurs during partial power generation of the fuel cell stack 10. Since the reaction gas can be supplied only to the reaction cell in which power generation is performed, the usable range for the supply flow rate of the reaction gas per unit reaction area (the supply flow rate of the reaction gas supplied to the reaction cell in which power generation is actually performed) is widened, which is suitable for low power operation. When flooding occurs, it is possible to operate the fuel cell stack 10 under the reaction gas supply flow rate and pressure conditions favorable for discharging generated water (condensate) (or conditions that allow more moisture to accumulate when drying occurs), , the voltage of the fuel cell stack 10 can be maintained more stably.

As another example, referring to FIG. 7 , according to a preferred embodiment of the present invention, the fuel cell stack 10 is fastened to the outermost ends of the first unit cell 100 and the second unit cell 200, an end plate 300 having a plurality of communication passages 302 communicating with the first manifold passage 118 and the second manifold passage 218; and a manifold block 400 provided at an end of the end plate 300 and including a plurality of guide passages 402 individually communicating with the communication passage 302. A plurality of open/close valves 510' provided in the manifold block 400 to individually open and close the guide passage 402 may be included.

As the opening/closing valve 510', a conventional valve or control member capable of selectively opening and closing the guide passage 402 may be used, and the present invention is not limited or limited by the type and structure of the opening/closing valve 510'. For example, a conventional solenoid valve may be used as the opening/closing valve 510'.

Referring to FIG. 8 , according to a preferred embodiment of the present invention, the fuel cell stack 10 is provided on the first separator unit 116 and is independently partitioned to correspond to the plurality of first partition plates 116a. a plurality of first cooling water passages 117 and a plurality of second cooling water passages 217 provided in the second separation plate unit 216 and independently partitioned to correspond to the plurality of second division separation plates 216a. can include

For example, the plurality of first coolant passages 117 may be independently partitioned (separated) by the first gasket 610 provided in the first separator unit 116 to correspond to the first partition plate 116a. The plurality of second coolant passages 217 may be independently partitioned (separated) by the second gasket 620 provided in the second separator unit 216 to correspond to the second partition plate 216a. can

In this way, the first cooling water passage 117 of the first unit cell 100 is partitioned by the plurality of first dividing plates 116a, so that all reaction cells of the fuel cell stack 10 (first reaction In the case of partial power generation using some of the cells and the second reaction cells), the supply of cooled guest water is partially allowed only to some of the plurality of first dividing plates 116a (first reaction cells in which power is actually generated) (O ), and it is possible to block (X) the supply of cooling water to other parts (first reaction cells in which power generation is not performed) of the plurality of first division plates 116a.

Similarly, during partial power generation of the fuel cell stack 10, partial supply of cooled passenger water is permitted (O) only to some of the plurality of second dividing plates 216a (second reaction cells in which power is actually generated), , It is possible to block (X) the supply of cooling water to other parts (second reaction cells in which power generation is not performed) of the plurality of second partition plates 216a.

For reference, when power is generated in all reaction cells (first reaction cell and second reaction cell) of the fuel cell stack 10, power is generated in all reaction cells under a low current condition, so that the fuel cell stack 10 fever can appear relatively low.

On the other hand, in the case of partial power generation using some of the entire reaction cells (first reaction cell and second reaction cell) of the fuel cell stack 10, since a relatively high current is used, the reaction cell (first reaction cell) in which power generation is actually performed Although the temperature of the first reaction cell and the second reaction cell may rise relatively high, according to the embodiment of the present invention, the cooling water is intensively supplied to the reaction cells (the first reaction cell and the second reaction cell) that generate high heat. Since it is possible to do this, overheating of the fuel cell stack 10 can be suppressed.

In addition, cooling water is supplied to the fuel cell stack 10 at a flow rate that can be supplied to all reaction cells (first reaction cells and second reaction cells), but during partial power generation of the fuel cell stack 10, actual power generation is not performed. Since cooling water can be supplied only to the reaction cell, the available range for the supply flow rate of cooling water per unit reaction area (the supply flow rate of cooling water supplied to the reaction cell in which power generation is actually performed) is widened to secure a margin of cooling capacity. Therefore, it is possible to more flexibly respond to the current limitation according to the temperature rise of the reaction cell using a high current.

On the other hand, during cold startup (or initial startup) of the fuel cell stack 10, power generation is not performed in all reaction cells (first reaction cells and second reaction cells) of the fuel cell stack 10, and the fuel cell stack Partial power generation may be performed only in some of the entire reaction cells (first reaction cell and second reaction cell) of (10). In this case, the cooling water may be used as a heat medium rather than a refrigerant, and it is possible to increase the temperature of the reaction cell in which power is actually generated more quickly by intensively supplying the cooling water to the reaction cell in which power is actually generated.

Meanwhile, in the embodiments of the present invention described above and illustrated, for example, a single gas diffusion layer is provided to commonly cover a plurality of split membrane electrode assemblies, and a plurality of divided separator plates are provided corresponding to the plurality of split membrane electrode assemblies. However, according to another embodiment of the present invention, it is also possible to provide a plurality of divided gas diffusion layers corresponding to a plurality of divided membrane electrode assemblies, and configure a single separator plate to cover the plurality of divided gas diffusion layers in common. do.

9 to 11 are fuel cell stacks according to another embodiment of the present invention. In addition, the same or equivalent reference numerals are given to the same or equivalent parts as the above-described configuration, and a detailed description thereof will be omitted.

9 to 11 are fuel cell stacks according to another embodiment of the present invention. In addition, the same or equivalent reference numerals are given to the same or equivalent parts as the above-described configuration, and a detailed description thereof will be omitted.

9 to 11, according to another preferred embodiment of the present invention, the fuel cell stack 10 includes a plurality of first reaction cells 110' electrically connected in parallel but independently capable of power generation. A first unit cell 100 'including; and a plurality of second reaction cells 210' electrically connected in parallel but provided to enable independent power generation, and electrically connected to the first unit cell 100' in series with the first unit cell 100'. ); but, the first unit cell 100' includes a plurality of first partition films that are independently divided to correspond to the plurality of first reaction cells 110'. The first membrane electrode assembly unit 112' including the electrode assembly 112a', and the plurality of membrane electrode assemblies stacked on the first membrane electrode assembly unit 112' to correspond to the plurality of first split membrane electrode assemblies 112a'. The first gas diffusion layer unit 114' including the first divided gas diffusion layer 114a' is laminated on the first gas diffusion layer unit 114' so as to commonly cover the plurality of first divided gas diffusion layers 114a'. It may include a first separator 116 'to be.

The first membrane electrode unit 112' includes a plurality of first divided membrane electrode assemblies 112a' that are independently divided to correspond to the first reaction cells 110'.

Here, the independent division of the plurality of first partitioned film electrode assemblies 112a' can be understood as electrically separating the plurality of first partitioned film electrode assemblies 112a' from each other.

Hereinafter, an example in which four first divided film electrode assemblies 112a' having a substantially rectangular shape are arranged on the same plane will be described.

The first split membrane electrode assembly 112a' is provided to generate electricity through an oxidation-reduction reaction between a fuel (eg, hydrogen) as a first reaction gas and an oxidizing agent (eg, air) as a second reaction gas.

The structure and material of the first split-membrane electrode assembly 112a' may be variously changed according to required conditions and design specifications, and the present invention is limited by the structure and material of the first partition-membrane electrode assembly 112a'. It is not limited or limited.

For example, the first split membrane electrode assembly 112a' may be configured by attaching a catalyst electrode layer in which an electrochemical reaction occurs on both sides of an electrolyte membrane centered on an electrolyte membrane through which hydrogen ions move.

The plurality of first partitioned membrane electrode assemblies 112a' may be divided in various ways according to required conditions and design specifications.

For example, the fuel cell stack 10 may include a first sealing member 310' provided in the first membrane electrode assembly unit 112' and independently partitioning the first divided membrane electrode assembly 112a'. In addition, the plurality of first divided film electrode assemblies 112a' may be independently divided through the first sealing member 310'.

More specifically, the first sealing member 310' includes the first edge sealing portion 312' provided along the edge of the first membrane electrode assembly unit 112', and the first divided film electrode assembly adjacent to each other ( 112a') may include a first intermediate sealing portion 314' provided between (boundary) and connected to the first edge sealing portion 312'.

The first sealing member 310' may be formed of an elastic material such as rubber, silicone, or urethane, and the present invention is not limited or limited by the material and characteristics of the first sealing member 310'.

The first gas diffusion layer unit 114' is a first membrane electrode assembly unit 112' to evenly distribute reactive gases (hydrogen or air) and deliver the generated electrical energy. ) is laminated on both sides of the

The first gas diffusion layer unit 114' includes a plurality of first divided gas diffusion layers 114a' that are independently divided to correspond to the plurality of first divided film electrode assemblies 112a'.

The first divided gas diffusion layer 114a' may be provided in various structures capable of diffusing reactive gases. For example, the first divided gas diffusion layer 114a' may have a porous structure having pores of a predetermined size.

The pore size and material of the first divided gas diffusion layer 114a' can be variously changed according to required conditions and design specifications, and the present invention is limited by the pore size and material of the first divided gas diffusion layer 114a'. It is not limited or limited.

The plurality of first divided gas diffusion layers 114a' may be divided in various ways according to required conditions and design specifications.

For example, the fuel cell stack 10 may include a second sealing member 320' provided in the first gas diffusion layer unit 114' and independently partitioning the first divided gas diffusion layer 114a'. , The plurality of first divided gas diffusion layers 114a' may be independently divided via the second sealing member 320'.

More specifically, the second sealing member 320' may include an intermediate sealing portion 322' provided between adjacent first divided gas diffusion layers 114a' (boundary).

The second sealing member 320' may be formed of an elastic material such as rubber, silicone, or urethane, and the present invention is not limited or limited by the material and characteristics of the second sealing member 320'.

The first separation plate 116' is composed of a single separation plate capable of commonly (entirely) covering a plurality of first divided gas diffusion layers 114a', and is laminated on both sides of the first gas diffusion layer unit 114'. do.

The first separator 116' is provided to perform a role of securing an air flow path and transferring current to an external circuit in addition to a role of blocking hydrogen and air.

In addition, the first separator 116' serves to distribute the heat generated in the first reaction cell 110' to the entire first reaction cell 110', and the excessively generated heat is removed from the first separator. Cooling water moving along the cooling passage (see 117 in FIG. 8) of 116' may be discharged to the outside.

In an embodiment of the present invention, the first separator 116' may be defined as including both an anode separator for forming a flow path for hydrogen as a fuel and a cathode separator for forming a flow path for air as an oxidant. there is.

For example, the first separator 116' may be formed of thin metal (eg, stainless steel, inconel, or aluminum). According to another embodiment of the present invention, it is also possible to form the first separator 116' with other materials such as graphite or a carbon composite material.

Referring to FIGS. 10 and 11 , the second unit cell 200' constitutes one fuel cell module independently of the first unit cell 100'.

More specifically, the second unit cell 200' is configured by electrically connecting (modularizing) a plurality of second reaction cells 210' capable of generating power independently in parallel.

Here, the second reaction cell 210' can be understood as a minimum fuel cell (minimum reaction area) capable of independently generating electricity.

The number of second reaction cells 210' constituting the second unit cell 200' may be variously changed according to required conditions and design specifications, and the number of second reaction cells 210' The invention is not limited or limited.

Hereinafter, an example in which the second unit cell 200' has the same structure as that of the first unit cell 100' will be described. According to another embodiment of the present invention, it is also possible to form the second unit cell and the first unit cell to have different structures.

For example, the second unit cell 200' may include four reaction cells electrically connected in parallel. Alternatively, the second unit cell may include 3 or less reaction cells or 5 or more reaction cells.

The second unit cell 200' may be provided in various structures including a plurality of second reaction cells 210'.

For example, the second unit cell 200' is a second membrane electrode assembly including a plurality of second divided membrane electrode assemblies 212a' independently divided to correspond to the plurality of second reaction cells 210'. unit 212', and a plurality of second divided gas diffusion layers 214a' stacked on the second membrane electrode assembly unit 212' to correspond to the plurality of second divided membrane electrode assemblies 212a'. It may include a gas diffusion layer unit 214', and a second separator 216' stacked on the second gas diffusion layer unit 214' so as to commonly cover the plurality of second divided gas diffusion layers 214a'. .

The second membrane electrode unit 212' includes a plurality of second divided membrane electrode assemblies 212a' that are independently divided to correspond to the second reaction cell 210'.

Here, the independent division of the plurality of second partitioned film electrode assemblies 212a' can be understood as electrically separating the plurality of second partitioned film electrode assemblies 212a' from each other.

Hereinafter, an example in which four second divided film electrode assemblies 212a' having a substantially rectangular shape are arranged on the same plane will be described.

The second split membrane electrode assembly 212a' is provided to generate electricity through an oxidation-reduction reaction between a fuel (eg, hydrogen) as a first reaction gas and an oxidant (eg, air) as a second reaction gas.

The structure and material of the second partition electrode assembly 212a' may be variously changed according to required conditions and design specifications, and the present invention is limited by the structure and material of the second partition electrode assembly 212a'. It is not limited or limited.

For example, the second split membrane electrode assembly 212a' may be configured by attaching a catalyst electrode layer in which an electrochemical reaction occurs on both sides of an electrolyte membrane centered on an electrolyte membrane through which hydrogen ions move.

The plurality of second partitioned membrane electrode assemblies 212a' may be divided in various ways according to required conditions and design specifications.

For example, the fuel cell stack 10 may include a third sealing member 330' provided in the second membrane electrode assembly unit 212' and independently partitioning the second partitioned membrane electrode assembly 212a'. In addition, the plurality of second divided film electrode assemblies 212a' may be independently divided through the third sealing member 330'.

More specifically, the third sealing member 330' includes the third edge sealing portion 332' provided along the edge of the second membrane electrode assembly unit 212', and the second divided film electrode assembly adjacent to each other ( 212a') and may include a third intermediate sealing portion 334' connected to the third edge sealing portion 332'.

The third sealing member 330' may be formed of an elastic material such as rubber, silicone, or urethane, and the present invention is not limited or limited by the material and characteristics of the third sealing member 330'.

The second gas diffusion layer unit 214' is a second membrane electrode assembly unit 212' so as to evenly distribute reactive gases (hydrogen or air) and deliver the generated electrical energy. ) is laminated on both sides of the

The second gas diffusion layer unit 214' includes a plurality of second divided gas diffusion layers 214a' that are independently divided to correspond to the plurality of second divided film electrode assemblies 212a'.

The second divided gas diffusion layer 214a' may be provided in various structures capable of diffusing reactive gases. For example, the second divided gas diffusion layer 214a' may have a porous structure having pores of a predetermined size.

The pore size and material of the second divided gas diffusion layer 214a' can be variously changed according to required conditions and design specifications, and the present invention is limited by the pore size and material of the second divided gas diffusion layer 214a'. It is not limited or limited.

The plurality of second divided gas diffusion layers 214a' may be divided in various ways according to required conditions and design specifications.

For example, the fuel cell stack 10 may include a fourth sealing member 340' provided in the second gas diffusion layer unit 214' and independently partitioning the second divided gas diffusion layer 214a'. , The plurality of second divided gas diffusion layers 214a' may be independently divided through the fourth sealing member 340'.

More specifically, the fourth sealing member 340' may include an intermediate sealing portion 342' provided between adjacent second divided gas diffusion layers 214a' (boundary).

The fourth sealing member 340' may be formed of an elastic material such as rubber, silicone, or urethane, and the present invention is not limited or limited by the material and characteristics of the fourth sealing member 340'.

The second separator 216' is composed of one separator capable of commonly (entirely) covering a plurality of second divided gas diffusion layers 214a', and is laminated on both sides of the second gas diffusion layer unit 214'. do.

The second separator 216' is provided to perform a role of securing an air flow path and transferring current to an external circuit in addition to a role of blocking hydrogen and air.

In addition, the second separator 216' serves to distribute the heat generated in the second reaction cell 210' to the entirety of the second reaction cell 210', and excessively generated heat is removed from the second separator. Cooling water moving along the cooling passage (see 217 in FIG. 8) of 216' may be discharged to the outside.

In an embodiment of the present invention, the second separator 216 ′ may be defined as including both an anode separator for forming a flow path for hydrogen as a fuel and a cathode separator for forming a flow path for air as an oxidant. there is.

For example, the second separator 216' may be formed of thin metal (eg, stainless steel, inconel, or aluminum). According to another embodiment of the present invention, it is also possible to form the second separator with other materials such as graphite or a carbon composite material.

According to another preferred embodiment of the present invention, the fuel cell stack 10 includes a plurality of first manifold passages 118 provided on the first separator 116' to correspond to the first divided gas diffusion layer 114a'. '), a first partition member 118a' provided on the first separation plate 116' and independently partitioning the first manifold passage 118' to correspond to the first divided gas diffusion layer 114a'; A plurality of second manifold passages 218' provided on the second separation plate 216' corresponding to the two-split gas diffusion layer 214a', and provided on the second separation plate 216', and the second divided gas A second partition member 218a' independently partitioning the second manifold passage 218' to correspond to the diffusion layer 214a' may be included.

For example, the first manifold flow path 118' may be formed at each end of the plurality of first separator plates 116', and the first partition member 118a' is the first manifold flow path 118'. It may be provided on the first separator 116' adjacent to, and the reaction gas ( hydrogen or air) may be supplied.

The second manifold passage 218' may be formed at each end of the plurality of second separator plates 216', and the second partition member 218a' is adjacent to the second manifold passage 218'. It may be provided on the second separator 216', and a reaction gas (hydrogen or air) may be supplied to each second reaction cell 210' via the second manifold passage 218'.

Although the above has been described with reference to the embodiments, these are merely examples and do not limit the present invention, and those skilled in the art to which the present invention belongs will not deviate from the essential characteristics of the present embodiment. It will be appreciated that various variations and applications are possible. For example, each component specifically shown in the embodiment can be modified and implemented. And differences related to these variations and applications should be construed as being included in the scope of the present invention as defined in the appended claims.

10: fuel cell stack
100: 1st unit cell
110: first reaction cell
112: first membrane electrode assembly unit
112a: first split membrane electrode assembly
114: first gas diffusion layer
116: first separator unit
116a: first dividing plate
117: first cooling water passage
118: first manifold flow path
200: second unit cell
210: second reaction cell
212: second membrane electrode assembly unit
212a: second membrane electrode assembly
214: second gas diffusion layer
216: second separator unit
217: second cooling water passage
216a: second dividing plate
218: second manifold flow path
300: end plate
302: communication passage
310: first sealing member
312: first edge sealing part
314: first intermediate sealing part
320: second sealing member
322: second edge sealing part
324: second intermediate sealing part
330: third sealing member
332: third edge sealing part
334: third intermediate sealing part
340: fourth sealing member
342: fourth edge sealing part
344: fourth intermediate sealing part
400: manifold block
402: guide flow
410: first voltage monitoring terminal
420: second voltage monitoring terminal
500: open/close unit
510,510': open/close valve
610: first gasket
620: second gasket

Claims (14)

A first unit cell including a plurality of first reaction cells electrically connected in parallel but independently capable of power generation; and
A second unit cell including a plurality of second reaction cells electrically connected in parallel but independently capable of power generation, and stacked on the first unit cell to be electrically connected in series with the first unit cell;
A fuel cell stack comprising a.
According to claim 1,
The first unit cell,
a first membrane electrode assembly unit including a plurality of first divided membrane electrode assemblies independently divided to correspond to the plurality of first reaction cells;
a first gas diffusion layer stacked on the first membrane electrode assembly unit so as to commonly cover the plurality of first split membrane electrode assemblies; and
a first separation plate unit including a plurality of first division and separation plates stacked on the first gas diffusion layer to correspond to the plurality of first division membrane electrode assemblies;
A fuel cell stack comprising a.
According to claim 2,
The second unit cell,
a second membrane electrode assembly unit including a plurality of second divided membrane electrode assemblies independently divided to correspond to the plurality of second reaction cells;
a second gas diffusion layer stacked on the second membrane electrode assembly unit to commonly cover the plurality of second divided membrane electrode assemblies; and
a second separator unit including a plurality of second partition separator plates stacked on the second gas diffusion layer to correspond to the plurality of second partition membrane electrode assemblies;
A fuel cell stack comprising a.
According to claim 3,
a first sealing member provided in the first membrane electrode assembly unit and independently partitioning the first divided membrane electrode assembly;
a second sealing member provided in the first separation plate unit and independently partitioning the first division and separation plate;
a third sealing member provided in the second membrane electrode assembly unit and independently partitioning the second divided membrane electrode assembly; and
A fuel cell stack including a fourth sealing member provided in the second separator unit and independently partitioning the second separator plate.
According to claim 4,
The first sealing member,
a first edge sealing portion provided along an edge of the first membrane electrode assembly unit; and a first intermediate sealing portion provided between adjacent first divided film electrode assemblies and connected to the first edge sealing portion,
The second sealing member,
a second edge sealing portion provided along an edge of the first separator unit; and a second intermediate sealing portion provided between the first divided film electrode assemblies adjacent to each other and connected to the second edge sealing portion,
The third sealing member,
a third edge sealing portion provided along an edge of the second membrane electrode assembly unit; and a third intermediate sealing portion provided between the second divided film electrode assemblies adjacent to each other and connected to the third edge sealing portion,
The fourth sealing member,
a fourth edge sealing portion provided along an edge of the second separator unit; and a fourth intermediate sealing part provided between the second partitioned membrane electrode assemblies adjacent to each other and connected to the fourth edge sealing part.
According to claim 3,
a first voltage monitoring terminal connected to at least one of the plurality of first division plates; and
a second voltage monitoring terminal connected to at least one of the plurality of second dividing plates;
A fuel cell stack comprising a.
According to claim 3,
first manifold passages provided on each of the first partitioning plates;
second manifold passages provided on each of the second partitioning plates and communicating with the first manifold passage; and
an opening/closing unit provided to be able to open and close the first manifold passage and the second manifold passage for each of the first division and separation plates and the second division and division plates;
A fuel cell stack comprising a.
According to claim 7,
An end plate fastened to the outermost ends of the first unit cell and the second unit cell and having a plurality of communication passages communicating with the first manifold passage and the second manifold passage,
The opening/closing unit includes a plurality of opening/closing valves provided on the end plate to individually open and close the communication passages.
According to claim 7,
an end plate fastened to outermost ends of the first unit cell and the second unit cell and having a plurality of communication passages communicating with the first manifold passage and the second manifold passage; and
A manifold block provided at an end of the end plate and including a plurality of guide passages individually communicating with the communication passage,
The fuel cell stack wherein the opening/closing unit includes a plurality of opening/closing valves provided on the manifold block to individually open and close the guide passages.
According to claim 3,
a plurality of first cooling water passages provided in the first separation plate unit and independently partitioned to correspond to the plurality of first division separation plates; and
a plurality of second cooling water passages provided in the second separator unit and independently partitioned to correspond to the plurality of second partition separator plates;
A fuel cell stack comprising a.
According to claim 1,
The first unit cell,
a first membrane electrode assembly unit including a plurality of first divided membrane electrode assemblies independently divided to correspond to the plurality of first reaction cells;
a first gas diffusion layer unit including a plurality of first divided gas diffusion layers stacked on the first membrane electrode assembly unit to correspond to the plurality of first divided membrane electrode assembly units; and
a first separator stacked on the first gas diffusion layer unit so as to commonly cover a plurality of the first divided gas diffusion layers;
A fuel cell stack comprising a.
According to claim 11,
The second unit cell,
a second membrane electrode assembly unit including a plurality of second divided membrane electrode assemblies independently divided to correspond to the plurality of second reaction cells;
a second gas diffusion layer unit including a plurality of second divided gas diffusion layers stacked on the second membrane electrode assembly unit to correspond to the plurality of second divided membrane electrode assembly units; and
A fuel cell stack comprising: a second separator stacked on the second gas diffusion layer unit so as to commonly cover the plurality of second divided gas diffusion layers.
According to claim 12,
a first sealing member provided in the first membrane electrode assembly unit and independently partitioning the first divided membrane electrode assembly;
a second sealing member provided in the first gas diffusion layer unit and independently partitioning the first divided gas diffusion layer;
a third sealing member provided in the second membrane electrode assembly unit and independently partitioning the second divided membrane electrode assembly; and
A fuel cell stack including a fourth sealing member provided in the second gas diffusion layer unit and independently partitioning the second divided gas diffusion layer.
According to claim 13,
a plurality of first manifold passages provided in the first separation plate to correspond to the first divided gas diffusion layer;
a first partition member provided on the first separation plate and independently partitioning the first manifold flow path to correspond to the first divided gas diffusion layer;
a plurality of second manifold passages provided in the second separation plate to correspond to the second divided gas diffusion layer; and
a second partition member provided on the second separation plate and independently partitioning the second manifold passage to correspond to the second divided gas diffusion layer;
A fuel cell stack comprising a.

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