Fuel cell stack

Abstract

The present invention relates to a fuel cell stack. One embodiment of the present invention provides a fuel cell stack comprising a plurality of fuel cell cells stacked therein, comprising a manifold that forms a flow path extending in the direction of cell stacking and supplies reaction gas to each cell, and a guide module connected to the end of the manifold and guiding the flow path of the reaction gas flowing into the manifold, wherein the guide module comprises a guide member rotatable with a preset axis as the axis of rotation and a rotation unit that controls the rotation angle of the guide member.

Description

Technology Field

[0001] The present invention relates to a fuel cell stack. Background Technology

[0002] Fuel cells are power generation devices that directly convert the chemical energy of hydrogen obtained from hydrocarbon-based substances such as natural gas, methanol, and ethanol, and oxygen from the air into electrical energy, possessing high efficiency and high energy density.

[0003] Representative examples of fuel cells include polymer electrolyte membrane fuel cells (PEMFCs) and direct methanol fuel cells (DMFCs). These fuel cells utilize a polymer membrane capable of conducting hydrogen ions as an electrolyte.

[0004] A polymer electrolyte fuel cell stack is formed by repeatedly stacking multiple separators and membrane electrode assemblies (MEAs).

[0005] In the above membrane electrode assembly, a fuel electrode (anode) and an air electrode (cathode) are formed on each side of the electrolyte membrane, and hydrogen gas and air (oxygen) are supplied to the fuel electrode and the air electrode, respectively, through a flow path formed on the surface of the separator plate.

[0006] Hydrogen ions ionized at the fuel electrode move through the electrolyte membrane to the air electrode to combine with oxygen to produce water, and an electric current is generated by the flow of electrons separated from the hydrogen.

[0007] The generated current is collected through current collector plates provided at both ends of the stack, converted into an appropriate form through a current converter, and then supplied to the point of use.

[0008] Here, a gasket is formed between the membrane electrode assembly and the separator of the unit cells to maintain airtightness between them. Additionally, each separator is formed with multiple manifolds to supply or discharge fuel and air to the membrane electrode assembly, discharge moisture which is a reaction byproduct, and flow a cooling medium such as cooling water.

[0009] Meanwhile, fuel cell vehicles employing fuel cell stacks must optimize the amount of fluid consumed while maintaining a constant consumption rate of the aforementioned fluid according to the power generation load corresponding to various driving conditions. However, in conventional technology, when the power generation load changes rapidly due to driving conditions such as rapid acceleration of the vehicle, the flow rate of the fluid supplied to the fuel cells is not uniform, which leads to a large voltage deviation among the fuel cells. In other words, in this case, a phenomenon occurs in which the flow rate of the fluid supplied to the fuel cells decreases in the section beyond a certain flow distance due to flow instability caused by changes in the fluid flow rate.

[0010] Conventional technology utilizes structures with fixed shapes on the manifold or follows a method where the flow path is formed without a structure. In a typical fuel cell stack without a structure, the cross-sectional area of ​​the flow path remains constant in the section away from the manifold inlet; therefore, during sudden changes in power generation load, a section occurs where the fluid supply flow rate decreases due to a partial drop in fluid pressure.

[0011] Accordingly, research and development on variable structures capable of controlling the flow path of reaction gases based on the voltage deviation of the solar or fuel cell of the reaction gas flow entering the manifold inlet is continuing. The problem to be solved

[0012] The technical problem that the present invention aims to solve is to increase the electricity production efficiency of a fuel cell stack by making the distribution of the reaction gas flowing toward a plurality of fuel cell cells uniform. means of solving the problem

[0013] One embodiment of the present invention provides a fuel cell stack comprising a plurality of fuel cell cells stacked therein, comprising a manifold that forms a flow path extending in the direction of cell stacking and supplies reaction gas to each cell, and a guide module connected to the end of the manifold and guiding the flow path of reaction gas flowing into the manifold, wherein the guide module comprises a guide member rotatable with a preset axis as the axis of rotation and a rotation unit that controls the rotation angle of the guide member.

[0014] In one embodiment of the present invention, the rotation unit may include a driving unit connected to one side of a guide member and providing power to the guide member, and a control unit that controls the operation of the driving unit.

[0015] In one embodiment of the present invention, a voltage sensing unit for detecting the magnitude of the voltage generated from each of a plurality of fuel cell cells may be further included.

[0016] In one embodiment of the present invention, the control unit can obtain information on the magnitude of the voltage of a fuel cell from a voltage sensing unit, and can control the operation of the driving unit using the obtained magnitude of the voltage of the fuel cell.

[0017] In one embodiment of the present invention, the control unit may have a voltage deviation detected in each of the plurality of fuel cell cells greater than a preset size.

[0018] In one embodiment of the present invention, a plurality of guide members are provided, and the plurality of guide members may be spaced apart at predetermined intervals along one direction.

[0019] In one embodiment of the present invention, a plurality of driving units are provided to be connected to a plurality of guide members, and a control unit can control the operation of each of the plurality of driving units to adjust the rotation angles of the plurality of guide members differently from each other.

[0020] In one embodiment of the present invention, the guide member may be formed in a plate shape.

[0021] In one embodiment of the present invention, the rotation axis of the guide member may be perpendicular to the longitudinal center axis of the flow path formed by the manifold.

[0022] In one embodiment of the present invention, the guide module may further include a main body portion that is detachably connected to the end of a manifold and has an inlet hole portion formed therein that is in communication with the manifold.

[0023] In one embodiment of the present invention, the guide member may be rotatably connected to the inner circumference of the inlet hole portion.

[0024] In one embodiment of the present invention, a sealing member may be disposed between the inner surface of the inlet hole portion and one side of a guide member connected to the inner surface of the inlet hole portion.

[0025] In one embodiment of the present invention, the manifold includes an oxygen manifold forming a flow path for oxygen and a hydrogen manifold forming a flow path for hydrogen, and an inlet hole formed in the main body may include an oxygen inlet hole portion communicating with the oxygen manifold and a hydrogen inlet hole portion spaced apart from the oxygen inlet hole portion and communicating with the hydrogen manifold.

[0026] In one embodiment of the present invention, a plurality of guide members may be provided to be connected to the inner surface of the oxygen inlet hole portion and the inner surface of the hydrogen inlet hole portion, respectively. Effects of the invention

[0027] A fuel cell stack according to one embodiment of the present invention includes a guide module that guides the flow path of a reaction gas introduced into a manifold, thereby enabling the uniform introduction of reaction gas into a plurality of fuel cell cells. Brief explanation of the drawing

[0028] FIG. 1 is a perspective view of a fuel cell stack according to one embodiment of the present invention. Figure 2 is a diagram illustrating the flow of reaction gas in a conventional fuel cell stack. FIG. 3 is a diagram illustrating the flow of reaction gas in a fuel cell stack including a guide module according to embodiments of the present invention. FIG. 4 is a perspective view of a guide module according to one embodiment of the present invention. Figure 5 is a cross-sectional view processed based on the line I-I' of Figure 4. Figure 6 is a cross-sectional view taken along the line II-II' of Figure 4. FIG. 7 is a cross-sectional view illustrating the usage state of a guide module in which the angle of the guide member is controlled integrally. FIG. 8 is a cross-sectional view illustrating the usage state of a guide module in which the angle of the guide member is divided and controlled. FIG. 9 is a perspective view of a guide module according to another embodiment of the present invention. Figure 10 is a cross-sectional view taken along the line III-III' of Figure 9. Figure 11 is a cross-sectional view taken along the line IV-IV' of Figure 9. Specific details for implementing the invention

[0029] The present invention is capable of various modifications and may have various embodiments; specific embodiments are illustrated in the drawings and described in detail in the detailed description. The effects and features of the present invention, and the methods for achieving them, will become clear by referring to the embodiments described below in detail together with the drawings. However, the present invention is not limited to the embodiments disclosed below but can be implemented in various forms.

[0030] Hereinafter, embodiments of the present invention will be described in detail with reference to the attached drawings. When describing with reference to the drawings, identical or corresponding components are given the same reference numerals, and redundant descriptions thereof will be omitted.

[0031] In the following examples, singular expressions include plural expressions unless the context clearly indicates otherwise.

[0032] In the following embodiments, terms such as "include" or "have" mean that the features or components described in the specification are present, and do not preclude the possibility that one or more other features or components may be added.

[0033] Where an embodiment can be implemented differently, a specific process sequence may be performed differently from the order described. For example, two processes described consecutively may be performed substantially simultaneously or proceed in the reverse order of the description.

[0034] In the drawings, the size of components may be exaggerated or reduced for convenience of explanation. For example, the size and thickness of each component shown in the drawings are depicted arbitrarily for convenience of explanation, so the following embodiments are not necessarily limited to those illustrated.

[0035] In the description of each component, where it is stated that it is formed on or under, "on" and "under" include both forms formed directly or through other components, and the criteria for "on" and "under" are explained based on the drawings.

[0036] FIG. 1 is a perspective view of a fuel cell stack according to one embodiment of the present invention, FIG. 2 is a drawing for explaining the flow of reaction gas in a conventional fuel cell stack, and FIG. 3 is a drawing for explaining the flow of reaction gas in a fuel cell stack including a guide module according to one embodiment of the present invention.

[0037] FIG. 4 is a perspective view of a guide module according to an embodiment of the present invention, FIG. 5 is a cross-sectional view taken along the line I-I' of FIG. 4, and FIG. 6 is a cross-sectional view taken along the line II-II' of FIG. 4.

[0038] FIG. 7 is a cross-sectional view illustrating the usage state of a guide module in which the angle of the guide member is controlled as a whole, and FIG. 8 is a cross-sectional view illustrating the usage state of a guide module in which the angle of the guide member is controlled in a divided manner.

[0039] Referring to FIG. 1, a fuel cell stack (1) according to one embodiment of the present invention may include a stack housing (10), a fuel cell cell (20), a manifold (100), a guide module (200), and a voltage sensing unit (300).

[0040] A fuel cell stack (1) produces electrical energy by electrochemically reacting a modified fuel with a predetermined reaction gas (air, oxygen, etc.). For example, it may have a structure in which a plurality of unit fuel cell cells (20) are stacked, and a single unit fuel cell cell (20) may consist of a membrane-electrode assembly (MEA) in which a fuel electrode and an air electrode are arranged around an electrolyte membrane, and a pair of separators arranged on both sides thereof.

[0041] At the fuel electrode, hydrogen is separated into hydrogen ions and electrons by a catalyst to generate electricity, while at the air electrode, hydrogen ions and electrons combine with oxygen to produce water.

[0042] The fuel cell stack (1), which is a core module constituting the hydrogen fuel cell power generation system, has components such as a membrane electrode assembly (MEA), a separator (bipolar plate, gas flow channel plate), a gasket, a current collector, and an end plate connected in series by fastening bolts.

[0043] The membrane electrode assembly (MEA), one of the core components constituting the main body of a polymer electrolyte membrane fuel cell, has a structure in which a gas diffusion electrode (GDE), composed of a catalyst layer and a gas diffusion layer (GDL), is integrated in a sandwich form on both sides of the polymer electrolyte membrane.

[0044] Separator plates equipped with fluid flow channels are in contact with both sides of the membrane electrode assembly (MEA). The fluid channels in the separator plates simultaneously serve to ensure that externally supplied hydrogen and air (oxygen) are uniformly supplied into each electrode without mixing, and to facilitate the smooth discharge of water generated during the electrode reaction.

[0045] In a fuel cell vehicle having such a configuration, the above-mentioned membrane electrode assembly, gas diffusion layer, and separator are sequentially and repeatedly stacked to form a stack module.

[0046] The stack housing (10) forms the exterior of the fuel cell stack (1), and a hole portion may be formed on one side for the reaction gas (G) to be introduced. Additionally, the interior of the fuel cell stack (1) may provide a space in which a fuel cell cell (20) can be seated. Specifically, a plurality of fuel cell cells (20) are provided, and the plurality of fuel cell cells (20) are spaced apart from each other at a predetermined interval and may be stacked along one direction (X-axis direction based on FIG. 2).

[0047] Referring to FIGS. 2 and 3, the manifold (100) supplies reaction gas (G) introduced from the supply pipe (30) to the fuel cell (20) and can form a flow path (P) extending along the one direction inside.

[0048] In this specification, 'reaction gas (G)' may be interpreted as oxygen, hydrogen, air, or a byproduct of a chemical reaction between oxygen and hydrogen.

[0049] The manifold (100) may include an inlet manifold (110) into which a reaction gas (G) is introduced from the outside, and an outlet manifold (120) spaced apart from the inlet manifold (110) and providing a path for the reaction gas (G) that has passed through the fuel cell cell (20) to be discharged to the outside.

[0050] The inlet manifold (110) may be positioned at one end of the fuel cell (20), and the outlet manifold (120) may be positioned at the other end of the fuel cell (20). Additionally, the internal space of the inlet manifold (110) and the outlet manifold (120) may be connected to the space between the multiple fuel cell cells (20).

[0051] Referring to FIGS. 4 to 8, a guide module (200) according to one embodiment of the present invention guides the flow path of a reaction gas (G) flowing into a manifold (100) and may include a main body (210), a guide member (220), and a rotation unit (230). Specifically, the guide module (200) may be positioned on the opening side of an inlet manifold (110) and may guide the flow path of a reaction gas (G) flowing into an inlet manifold (110).

[0052] In this specification, the guide module (200) is described as being formed separately from the manifold (100) or stack housing (10) and detachably connected to each other, but this is merely one embodiment, and the guide module (200) may be formed integrally with the manifold (100) or stack housing (10).

[0053] Specifically, the main body (210) can be interpreted as an area of ​​the outer wall of the manifold (100) or the outer wall of the stack housing (10), and the guide member (220) can be rotatably connected to the inner surface of the manifold (100) or the inner surface of the stack housing (10).

[0054] Referring to FIGS. 4 to 8, an inlet hole portion (211) communicating with the manifold (100) of the main body portion (210) according to one embodiment of the present invention may be formed in the shape of a hole portion. Specifically, the inlet hole portion (211) may communicate with the inlet manifold (110), and a reaction gas (G) may pass through the inlet hole portion (211) and flow into the inlet manifold (110).

[0055] Meanwhile, the manifold (100) may include an oxygen inlet manifold (drawing symbol not set) into which oxygen gas is introduced and a hydrogen inlet manifold (drawing symbol not set) spaced apart from the oxygen inlet manifold into which hydrogen gas is introduced.

[0056] Referring to FIGS. 4 to 8, the inlet hole portion (211) may include an oxygen inlet hole portion (212) and a hydrogen inlet hole portion (213) formed spaced apart from each other on the main body portion (210). Specifically, the oxygen inlet hole portion (212) may be in communication with an oxygen inlet manifold, and the hydrogen inlet hole portion (213) may be in communication with a hydrogen inlet manifold.

[0057] In one embodiment, the diameter of the oxygen inlet hole (212) may be relatively larger than the diameter of the hydrogen inlet hole (213), and the center of the oxygen inlet hole (212) and the center of the hydrogen inlet hole (213) may both be located on the longitudinal central axis of the main body (210).

[0058] In this specification, 'inlet hole portion (211)' is defined as a collective term for the oxygen inlet hole portion (212) and the hydrogen inlet hole portion (213).

[0059] Additionally, 'inlet manifold (110)' is defined as a general term for the oxygen inlet manifold and the hydrogen inlet manifold.

[0060] The longitudinal central axis of the inlet hole section (211) may be coaxial with the longitudinal central axis (AX2) of the inlet manifold (110). Specifically, the longitudinal central axis of the oxygen inlet hole section (212) may be coaxial with the longitudinal central axis of the oxygen inlet manifold, and the longitudinal central axis of the hydrogen inlet hole section (213) may be coaxial with the longitudinal central axis of the hydrogen inlet manifold.

[0061] Although not illustrated in the drawing, in one embodiment, the inlet hole portion (211) may be formed with a shape in which the diameter gradually widens as it moves toward the inlet manifold (110). Specifically, on the area adjacent to the inlet manifold (110), the inlet hole portion (211) may be formed with a section in which the diameter gradually widens as it gets closer to the inlet manifold (110).

[0062] In an optional embodiment, at the end of the inlet manifold (110) adjacent to the guide module (200), a section with a diameter that widens in a direction away from the guide module (200) may be formed.

[0063] As a result, the reaction gas (G) flowing into the inlet manifold (110) through the inlet hole (211) of the guide module (200) passes through the section where the diameter gradually widens, thereby reducing the flow rate of the reaction gas (G) or reducing the drop in pressure, and thereby increasing the electrical production efficiency of the fuel cell stack (1).

[0064] A plate-shaped guide member (220) can be rotatably connected to the inner surface of the inlet hole (211). As a result, the flow path of the reaction gas (G) passing through the inlet hole (211) can be changed according to the rotation angle of the guide member (220). A detailed explanation regarding this will be provided in the description of the guide member (220) and the rotation unit (230).

[0065] An elastic sealing member (not shown in the drawing) may be disposed between the inner surface of the inlet hole (211) and the guide member (220). This prevents the reaction gas (G) or fluid from leaking to the outside through the interface between the guide member (220) and the inlet hole (211).

[0066] Referring to FIGS. 4 and 5, a guide member (220) according to one embodiment of the present invention guides the flow path of a reaction gas (G) inside an inlet hole (211) and can rotate with a pre-set axis inside the inlet hole (211) as the axis of rotation.

[0067] Hereinafter, the rotation axis (AX1) of the guide member (220) may also be referred to as the ‘first axis (AX1)’, and the longitudinal center axis (AX2) of the manifold (100) or the flow path (P) formed by the manifold (100) may also be referred to as the ‘second axis (AX2)’.

[0068] A plurality of guide members (220) according to one embodiment of the present invention are provided, and the plurality of guide members (220) may be spaced apart at predetermined intervals along one direction (Z-axis direction based on FIG. 4).

[0069] The above one direction may be perpendicular to the direction of the rotation axis (AX1) of the guide member (220), and furthermore, the above one direction may be perpendicular to the length direction of the flow path (P) formed by the manifold (100).

[0070] In one embodiment, the rotation axis (AX1) of the guide member (220) may be perpendicular to the longitudinal center axis (AX2) of the flow path (P) formed by the manifold (100).

[0071] A guide member (220) can be rotatably connected to the inner circumference of the inlet hole portion (211), and specifically, a plurality of guide members (220) can be rotatably connected to the inner circumference of the oxygen inlet hole portion (212) and the inner circumference of the hydrogen inlet hole portion (213), respectively.

[0072] Referring to FIGS. 4 to 6, a guide member (220) according to one embodiment of the present invention may be formed in the shape of a flat plate.

[0073] In an optional embodiment, the guide member (220) may be formed in the shape of a plate in which curvature is formed along the longitudinal direction of the manifold (100). In this case, the curvature in the second axis (AX2) direction of the plurality of guide members (220) may be formed differently from each other.

[0074] Specifically, the curvature in the second axis (AX2) direction of the guide member (220) adjacent to the fuel cell (20) may be greater than the curvature in the second axis (AX2) direction of the guide member (220) positioned relatively far from the fuel cell (20).

[0075] Alternatively, a guide member (220) adjacent to a fuel cell (20) may be formed in the shape of a curved plate having a curvature in the direction of the second axis (AX2), and a guide member (220) positioned relatively far from the fuel cell (20) may be formed in the shape of a flat plate.

[0076] Referring to FIGS. 4 to 8, a rotation unit (230) according to one embodiment of the present invention controls the rotation angle of a guide member (220) and may include a driving unit (231) and a control unit (235).

[0077] The driving unit (231) provides power to the guide member (220) and can be connected to the guide member (220). The driving unit (231) may include a link structure connected to the guide member (220) and can provide power to the guide member (220) through the link structure.

[0078] In one embodiment, the driving unit (231) can generate torque by receiving power from an external source and can transmit the generated torque to the guide member (220) to rotate the guide member (220) to a preset angle.

[0079] In one embodiment, the driving unit (231) can perform linear motion by receiving power from an external source, and thereby the driving unit (231) can rotate the guide member (220) to a preset angle by transmitting a linear force to one side of the link structure.

[0080] The drive unit (231) may be composed of various devices capable of rotating or linear motion by receiving power from an external source, such as a vacuum or electric diaphragm, a solenoid, an actuator, a hydraulic motor, or an electric motor.

[0081] A plurality of driving units (231) may be provided to be connected to each of a plurality of guide members (220). Specifically, the driving unit (231) may include a first driving unit (232) that provides power to a guide member (220) disposed inside the oxygen inlet hole (212) and a second driving unit (233) that provides power to a guide member (220) disposed inside the hydrogen inlet hole (213).

[0082] The first driving unit (232) is connected to a guide member (220) positioned inside the oxygen inlet hole (212), and the second driving unit (233) can be connected to a guide member (220) positioned inside the hydrogen inlet hole (213).

[0083] The first drive unit (232) and the second drive unit (233) may be made of separate drive devices, but this is merely one embodiment, and the first drive unit (232) and the second drive unit (233) may be made of a single drive device.

[0084] In this specification, 'drive unit (231)' is defined as a collective term for the first drive unit (232) and the second drive unit (233).

[0085] Referring to FIG. 7, the driving unit (231) is connected to a plurality of guide members (220) and can rotate the plurality of guide members (220) as a single unit. In the above, "rotating as a single unit" means a state in which the guide members (220) receive rotational force simultaneously and rotate. In this case, the plurality of guide members (220) can be connected to each other, and the guide members (220) connected to each other can receive power from the driving unit (231) and rotate as a single unit by a preset angle.

[0086] However, when multiple guide members (220) 'rotate as a single unit', it does not mean that the rotation angles of the multiple guide members (220) are the same as each other.

[0087] Referring to FIG. 8, the first driving unit (232) may include a first-1 driving unit (2321) that provides driving force to some of the plurality of guide members (220) disposed inside the oxygen inlet hole (212), and a first-2 driving unit (2322) that provides driving force to the remaining guide members (220).

[0088] Additionally, the second driving unit (233) may include a second-1 driving unit (2331) that provides driving force to some of the plurality of guide members (220) disposed inside the hydrogen inlet hole (213), and a second-2 driving unit (2332) that provides driving force to the remaining guide members (220).

[0089] In this case, the guide member (220) that rotates by receiving power from the first-1 drive unit (2321) and the guide member (220) that rotates by receiving power from the first-2 drive unit (2322) can rotate independently of each other, and the control unit (235) can independently control the rotation of the guide member (220) connected to the first-1 drive unit (2321) and the rotation of the guide member (220) connected to the first-2 drive unit (2322).

[0090] Additionally, the guide member (220) that rotates by receiving power from the 2-1 drive unit (2331) and the guide member (220) that rotates by receiving power from the 2-2 drive unit (2332) can rotate independently of each other, and the control unit (235) can independently control the rotation of the guide member (220) connected to the 2-1 drive unit (2331) and the rotation of the guide member (220) connected to the 2-2 drive unit (2332).

[0091] The first-1 drive unit (2321) and the first-2 drive unit (2322) may be made of separate drive devices, but this is merely one embodiment, and the first-1 drive unit (2321) and the first-2 drive unit (2322) may be made of a single drive device.

[0092] Additionally, the 2-1 drive unit (2331) and the 2-2 drive unit (2332) may be made of separate drive devices, but this is merely one embodiment, and the 2-1 drive unit (2331) and the 2-2 drive unit (2332) may be made of a single drive device.

[0093] As a result, it is possible to control the rotation of each of the multiple guide members (220) independently / selectively, thereby enabling more precise control of the flow path of the reaction gas (G) passing through the guide members (220) compared to when the rotation of the multiple guide members (220) is controlled as a whole.

[0094] In FIG. 8, a plurality of guide members (220) disposed inside the inlet hole (211) are described as being separated into two bundles, but this is merely one embodiment, and the plurality of guide members (220) can be separated into n bundles (n is 3 or more), and in this case, the control unit (235) can independently control the rotation of each bundle, and the larger the size of n, the more finely the flow of the reaction gas (G) passing through each region of the inlet hole (211) can be controlled.

[0095] Referring to FIGS. 4 to 8, a control unit (235) according to one embodiment of the present invention controls the operation of a driving unit (231) and can be electrically connected to the driving unit (231).

[0096] Referring to FIG. 7, the control unit (235) can control the rotation angle of the guide member (220) placed inside the oxygen inlet hole (212) by controlling the drive of the first drive unit (232), and can control the rotation angle of the guide member (220) placed inside the hydrogen inlet hole (213) by controlling the drive of the second drive unit (233).

[0097] Referring to FIG. 8, the control unit (235) can control the rotation angle of a portion of a plurality of guide members (220) disposed inside the oxygen inlet hole (212) by controlling the drive of the first-1 drive unit (2321), and can control the rotation angle of the remaining guide members (220) disposed inside the oxygen inlet hole (212) by controlling the drive of the first-2 drive unit (2322).

[0098] Additionally, the control unit (235) can control the rotation angle of a portion of a plurality of guide members (220) disposed inside the hydrogen inlet hole (213) by controlling the drive of the 2-1 drive unit (2331), and can control the rotation angle of the remaining guide members (220) disposed inside the hydrogen inlet hole (213) by controlling the drive of the 2-2 drive unit (2332).

[0099] Referring to FIGS. 2 and FIGS. 3, a fuel cell stack (1) according to one embodiment of the present invention may include a voltage sensing unit (300) capable of measuring the magnitude of a voltage (hereinafter referred to as 'cell voltage') generated from each of the fuel cell cells (20), and a control unit (235) may be electrically connected to the voltage sensing unit (300) to obtain cell voltage information from the voltage sensing unit (300) and control the driving of a driving unit (231).

[0100] Referring to FIG. 2, if the flow rate of the reaction gas (G) flowing into each fuel cell (20) through the inlet manifold (110) is not uniform, the variation in the magnitude of the cell voltage of each fuel cell (20) becomes large, and as a result, the efficiency of the fuel cell stack (1) may be lowered.

[0101] Specifically, the reaction gas (G) flowing into the manifold (100) through the supply pipe (30) may have a flow rate of the reaction gas (G) flowing into the fuel cell (20) near the inlet end due to causes such as inertial force or centrifugal force, which may be relatively lower than the flow rate of the reaction gas (G) flowing into the fuel cell (20) relatively far from the inlet end. As a result, the cell voltage of the fuel cell (20) near the inlet end may be relatively lower than the cell voltage of the fuel cell (20) relatively far from the inlet end.

[0102] Referring to FIG. 3, when the flow path of the reaction gas (G) flowing into the inlet end is guided to the fuel cell (20) side near the inlet end using a guide module (200), the flow rate of the reaction gas (G) flowing into the fuel cell (20) side near the inlet end and the flow rate of the reaction gas (G) flowing into the fuel cell (20) side relatively far from the inlet end can be made uniform. Through this, the cell voltage of the fuel cell (20) near the inlet end and the cell voltage of the fuel cell (20) relatively far from the inlet end become uniform, thereby lowering the overall deviation of the cell voltage and increasing the electricity production efficiency of the fuel cell stack (1).

[0103] The control unit (235) can obtain information on the magnitude of the cell voltage of the fuel cell (20) from the voltage detection unit (300), and can control the operation of the driving unit (231) using the obtained magnitude of the cell voltage of the fuel cell (20).

[0104] The control unit (235) can obtain information on the magnitude of the cell voltage of the fuel cell (20) from the voltage detection unit (300) and calculate the deviation of the cell voltage generated in a plurality of fuel cell cells (20), and can control the operation of the driving unit (231) using the calculated deviation of the cell voltage.

[0105] In one embodiment, when the cell voltage generated in the fuel cell (20) near the inlet end is measured to be lower than the cell voltage generated in another fuel cell (20), the control unit (235) can control the driving unit (231) to adjust the angle of the guide member (220) so that the end of the guide member (220) faces the fuel cell (20) near the inlet end.

[0106] In one embodiment, when the cell voltage generated in a fuel cell (20) placed at a specific location is measured to be lower than the cell voltage generated in another fuel cell (20), the control unit (235) can control the driving unit (231) to adjust the angle of the guide member (220) so that the end of the guide member (220) faces the side of the fuel cell (20) placed at the specific location.

[0107] In one embodiment, the control unit (235) can independently adjust the rotation angle of a plurality of guide members (220) using the magnitude of the acquired cell voltage generated in each fuel cell (20).

[0108] As a result, by utilizing the magnitude or deviation of the cell voltage generated in the plurality of fuel cell cells (20), the rotation angle of the plurality of guide members (220) can be adjusted to guide more reaction gas (G) to flow into the fuel cell cell (20) with a lower cell voltage, and thereby, the efficiency of the fuel cell stack (1) can be increased by uniformly controlling the flow rate of the reaction gas (G) flowing into each of the plurality of fuel cell cells (20).

[0110] Hereinafter, a guide module (200') according to another embodiment of the present invention will be described. Except for the fact that the guide module (200') according to another embodiment of the present invention includes a first guide member (221') and a second guide member (222') arranged to intersect each other, the configuration and effect of the guide module (200) according to one embodiment of the present invention are identical, so a description in the overlapping scope is omitted.

[0111] FIG. 9 is a perspective view of a guide module according to another embodiment of the present invention, FIG. 10 is a cross-sectional view taken along the line III-III' of FIG. 9, and FIG. 11 is a cross-sectional view taken along the line IV-IV' of FIG. 9.

[0112] Referring to FIG. 9, a guide member (220') according to another embodiment of the present invention may include a first guide member (221') and a second guide member (222') that are disposed inside the inlet hole portion (211) and rotate on different axes.

[0113] Referring to FIGS. 10 and 11, the rotation axis (AX1-1) of the first guide member (221') and the rotation axis (AX1-2) of the second guide member (222') may be perpendicular to each other.

[0114] Since the first guide member (221) has the same operating principle and effect as the guide member (220) according to one embodiment of the present invention, a description related thereto is omitted.

[0115] A plurality of second guide members (222') are provided, and the plurality of second guide members (222') can be spaced apart at predetermined intervals along one direction (Y-axis direction based on FIG. 9).

[0116] The above one direction may be perpendicular to the direction of the rotation axis (AX1-2) of the second guide member (222'), and furthermore, the above one direction may be perpendicular to the length direction of the flow path (P) formed by the manifold (100).

[0117] In one embodiment, the rotation axis (AX1-2) of the second guide member (222') may be perpendicular to the longitudinal center axis (AX2) of the flow path (P) formed by the manifold (100).

[0118] Referring to FIGS. 9 to 11, the second guide member (222') can be rotatably connected to the inner circumference of the inlet hole portion (211), and specifically, a plurality of second guide members (222') can be rotatably connected to the inner circumference of the oxygen inlet hole portion (212) and the inner circumference of the hydrogen inlet hole portion (213), respectively.

[0119] The second guide member (222') may be formed in the shape of a flat plate. However, it is not limited thereto, and the second guide member (222') may be formed in the shape of a plate with curvature formed along the longitudinal direction of the manifold (100). In this case, the curvature in the direction of the second axis (AX2) of the plurality of second guide members (222') may be formed differently from each other.

[0120] The control unit (235) can control the driving of the driving unit (231) to adjust the rotation angle of the second guide member (222'), and thereby, when the flow of the reaction gas (G) introduced through the inlet hole (211) is biased to one side, the second guide member (222') can be rotated to a predetermined angle to uniformly control the flow of the reaction gas (G).

[0121] Although not shown in the drawing, the control unit (235) can control the drive of the drive unit (231) to rotate a plurality of second guide members (222') as a whole, and can also independently control the rotation angles of some and the rest of the plurality of second guide members (222').

[0122] In conclusion, the fuel cell stack (1) according to the embodiments of the present invention includes a guide module (200) that guides the flow path of the reaction gas (G) introduced into the manifold (100), thereby enabling the uniform introduction of the reaction gas (G) into a plurality of fuel cell cells (20).

[0123] The scope of the present invention is not limited to the embodiments described above, and all scopes equivalent to or equivalently modified from the claims set forth below, as well as the claims set forth below, shall be considered to fall within the scope of the concept of the present invention. Explanation of the symbols

[0124] 1: Fuel cell stack 100: Manifold 200: Guide Module 210: Main Body 220: Guide member 230: Rotating unit 300: Voltage sensing unit

Claims

Claim 1 A fuel cell stack comprising a plurality of fuel cell cells, wherein the stack comprises: a manifold that forms a flow path extending in the direction of cell stacking and supplies reaction gas to each of the plurality of fuel cell cells; a guide module located at the end of the manifold and guiding the flow path of the reaction gas flowing into the manifold; and a voltage sensing unit that measures the magnitude of the voltage generated from each of the plurality of fuel cell cells; wherein the guide module comprises: a main body portion that is detachably connected to the end of the manifold and has an inlet hole portion formed therein that communicates with the manifold; a plurality of guide members that are rotatably connected to the inner circumference of the inlet hole portion and are rotatable with a preset axis as the rotation axis; and a rotation unit that controls the rotation angle of the plurality of guide members; wherein the plurality of guide members are spaced apart at a preset interval along one direction; and wherein the manifold comprises: an oxygen manifold that forms a flow path for oxygen flow; and a hydrogen manifold that forms a flow path for hydrogen flow; wherein the inlet hole portion comprises an oxygen inlet hole portion that communicates with the oxygen manifold. and a hydrogen inlet hole portion spaced apart from the oxygen inlet hole portion and communicating with the hydrogen manifold; wherein the plurality of guide members are each rotatably connected to the inner surface of the oxygen inlet hole portion and the inner surface of the hydrogen inlet hole portion, and the rotation unit comprises: a driving unit that provides power to the plurality of guide members; and a control unit that controls the operation of the driving unit.The driving unit comprises a first-1 driving unit that provides driving force to some guide members among a plurality of guide members disposed inside the oxygen inlet hole portion, a first-2 driving unit that provides driving force to the remaining guide members excluding the said some guide members among the plurality of guide members disposed inside the oxygen inlet hole portion, a second-1 driving unit that provides driving force to some guide members among a plurality of guide members disposed inside the hydrogen inlet hole portion, and a second-2 driving unit that provides driving force to the remaining guide members excluding the said some guide members among the plurality of guide members disposed inside the hydrogen inlet hole portion. The control unit obtains information on the magnitude of the voltage of each of the plurality of fuel cell cells from the voltage sensing unit, and when the deviation of the voltage detected in each of the plurality of fuel cell cells is greater than or equal to a preset magnitude, it independently controls the operation of the first-1 driving unit, the first-2 driving unit, the second-1 driving unit, and the second-2 driving unit, so that a fuel cell in which a voltage lower than the voltage generated in another fuel cell among the plurality of fuel cell cells is measured Adjusting the rotation angles of the plurality of guide members disposed in the oxygen inlet hole and the hydrogen inlet hole differently from each other so that the ends of the plurality of guide members face each other; Fuel cell stack. Claim 2 delete Claim 3 delete Claim 4 delete Claim 5 delete Claim 6 delete Claim 7 A fuel cell stack according to claim 1, wherein the one direction is perpendicular to the rotational axis direction of the guide member and the longitudinal direction of the flow path formed by the manifold, respectively. Claim 8 delete Claim 9 A fuel cell stack according to claim 1, wherein the guide member is formed in a plate shape. Claim 10 A fuel cell stack according to claim 1, wherein the rotation axis of the guide member is perpendicular to the longitudinal center axis of the flow path formed by the manifold. Claim 11 delete Claim 12 delete Claim 13 A fuel cell stack according to claim 1, wherein a sealing member is disposed between the inner surface of the inlet hole portion and one side of the guide member connected to the inner surface of the inlet hole portion. Claim 14 delete Claim 15 delete

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