Fuel cell device

Abstract

Disclosed is a fuel cell apparatus including: a fuel cell including a stack including a plurality of unit cells stacked in a first direction; the cell monitoring connector is mounted to the fuel cell in a second direction crossing the first direction. The fuel cell includes a plurality of separators included in each of the unit cells and spaced apart from each other in the first direction, each separator including an outer side surface in which a concave-type connection portion is formed in a concave manner. The battery monitoring connector includes a housing and a male connection portion protruding convexly from the housing to mate with the female connection portion and in surface contact with an outer surface of each separator plate within the female connection portion.

Description

Technical Field

[0001] The present invention relates to a fuel cell device. Background Art

[0002] The battery stack of a fuel cell can supply the electric power generated by an electrochemical reaction between air supplied to one surface of a polymer electrolyte membrane and hydrogen supplied to the opposite surface of the polymer electrolyte membrane to an external load.

[0003] The battery stack may have a structure in which hundreds of unit cells are stacked. When the unit cells operate normally during the operation of the battery stack, the unit cells can form a voltage of a predetermined magnitude. In this case, if any one of the hundreds of cells fails to exhibit normal performance, the total output of the battery stack decreases. If this reverse voltage phenomenon continues, it is necessary to stop the operation of the battery stack.

[0004] The battery monitoring connector of a fuel cell device checks the state of each unit cell and continuously monitors the voltage of each unit cell. To this end, the battery monitoring connector can be in electrical contact with the battery to check the voltage of each unit cell forming the battery stack. Various structures of the electrical connection between the battery monitoring connector and the battery stack are currently under study.

[0005] The information disclosed in the background art of the present invention is only for enhancing the understanding of the general background art of the present invention and may not be regarded as an admission or any form of suggestion that this information forms the prior art known to those skilled in the art. Summary of the Invention

[0006] Aspects of the present invention are directed to providing a fuel cell device that substantially avoids one or more problems due to the limitations and disadvantages of the prior art.

[0007] Embodiments provide a fuel cell device in which a fuel cell and a battery monitoring connector are easily and quickly assembled with each other.

[0008] However, the objects achieved by the exemplary embodiments are not limited to the above objects, and other objects not mentioned herein will be clearly understood by those skilled in the art from the following description.

[0009] Other advantages, objects, and features of the present invention will be partially set forth in the following description, and will be partially obvious to those of ordinary skill in the art after studying the following, or may be learned from the practice of the present invention. The objects and other advantages of the present invention can be realized and obtained by the structures particularly pointed out in the written description and its claims, as well as the drawings.

[0010] According to an exemplary embodiment of the present invention, a fuel cell device may include: a fuel cell including a cell stack including a plurality of unit cells stacked in a first direction; and a battery monitoring connector mounted to the fuel cell in a second direction intersecting the first direction. The fuel cell may include a plurality of separators including in each of the unit cells and spaced apart from each other in the first direction, and each separator may include an outer surface in which a first connection portion is formed in a recessed manner. The battery monitoring connector may include a housing and a second connection portion protruding from the housing to cooperate with the first connection portion and making surface contact with the outer surface of each separator within the first connection portion.

[0011] In an exemplary embodiment of the present invention, the second connection portion may be locked in a state of cooperating with the first connection portion by a spring force of the second connection portion.

[0012] In an exemplary embodiment of the present invention, the housing may include: a front surface on which the second connection portion is provided; and a rear surface formed opposite to the front surface in the second direction, and the fuel cell may further include end plates provided at respective ends of the cell stack.

[0013] In an exemplary embodiment of the present invention, the fuel cell device may further include a fixing frame provided on the rear surface of the housing and supporting the housing, and the fixing frame may include: a support portion provided on the rear surface of the housing; and engaging portions formed at a first end portion and a second end portion of the support portion in the first direction to engage with the end plates.

[0014] In an exemplary embodiment of the present invention, the fuel cell device may further include a control circuit connected to the battery monitoring connector, and the control circuit may be provided between the rear surface of the housing and the fixing frame.

[0015] In an exemplary embodiment of the present invention, each unit cell may include a membrane electrode assembly, and the membrane electrode assembly may include: a reaction surface provided at a central portion of the membrane electrode assembly; and a sub-gasket provided around the reaction surface.

[0016] In an exemplary embodiment of the present invention, the sub-gasket may be disposed between a first partition and a second partition adjacent to each other among a plurality of partitions, and the second connecting portion may include a first second connecting portion and a second second connecting portion formed to be in surface contact with the first partition and the second partition, respectively. The sub-gasket may include: a first portion disposed between the first partition and the second partition and spaced apart from the first partition and the second partition in the first direction; and a second portion extending from the first portion in the second direction and disposed between the first second connecting portion and the second second connecting portion and spaced apart from the first second connecting portion and the second second connecting portion in the first direction.

[0017] In an exemplary embodiment of the present invention, the sub-gasket may include a film-type insulating material.

[0018] In an exemplary embodiment of the present invention, the sub-gasket may include a PEN film.

[0019] In an exemplary embodiment of the present invention, an outer surface of each partition in surface contact with the second connecting portion may have a first thickness in the first direction, and the second connecting portion in surface contact with the outer surface of each partition may have a second thickness in the first direction.

[0020] In an exemplary embodiment of the present invention, a portion where the outer surface having the first thickness and the second connecting portion having the second thickness overlap each other in the second direction may have an overlap thickness in the first direction, and the overlap thickness may be greater than or equal to half of the first thickness or the second thickness.

[0021] In an exemplary embodiment of the present invention, an outer surface of each partition within the first connecting portion in surface contact with the second connecting portion may have a uniform thickness, and the second connecting portion in surface contact with the outer surface of each partition may have a uniform thickness.

[0022] In an exemplary embodiment of the present invention, the first connecting portion may have a V shape, a rectangular shape, or an arc shape.

[0023] In an exemplary embodiment of the present invention, the second connecting portion and each partition may not overlap each other in the first direction.

[0024] It should be understood that the above general description and the following detailed description of the present invention are exemplary and explanatory, and are intended to provide further explanation of the claimed invention.

[0025] The methods and devices of the present invention have other features and advantages that will be apparent from or more particularly set forth in the accompanying drawings incorporated herein and the following detailed description, which together are used to explain certain principles of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 is a cross-sectional view of an end plate of a fuel cell and a fuel cell stack;

[0027] Figure 2 is an exploded perspective view of a separator and a cell monitoring connector according to an exemplary embodiment of the present invention;

[0028] Figure 3 is a partially exploded perspective view of the separator and the cell monitoring connector according to the embodiment;

[0029] Figure 4A and Figure 4B are respectively Figure 3 a partial engagement front view and an exploded front view of the separator and the cell monitoring connector shown;

[0030] Figure 5A and Figure 5B are respectively Figure 4A an engagement cross-sectional view and an exploded cross-sectional view taken along line A-A' in

[0031] Figure 6A , Figure 6B and Figure 6C are views showing exemplary shapes of a concave connecting portion and a convex connecting portion;

[0032] Figure 7A is a front view of an exemplary embodiment of a membrane electrode assembly;

[0033] Figure 7B is a front view of an exemplary embodiment of a separator;

[0034] Figure 8A is an exploded perspective view of a fuel cell device according to another exemplary embodiment of the present invention; and

[0035] Figure 8B is Figure 8A an assembled perspective view of the fuel cell device shown.

[0036] It will be understood that the drawings are not necessarily to scale, presenting a somewhat simplified representation of various features illustrative of the basic principles of the present invention. Specific design features of the present invention as included herein, including for example specific dimensions, orientations, positions, and shapes, will be determined in part by the particular intended application and use environment.

[0037] In the accompanying drawings, in several of the drawings of the accompanying drawings, reference numerals refer to the same or equivalent parts of the present invention. Detailed Embodiments

[0038] Reference will now be made in detail to various embodiments of the present invention, examples of which are illustrated in the accompanying drawings and described below. While the present invention will be described in conjunction with the exemplary embodiments of the present invention, it will be understood that this description is not intended to limit the present invention to those exemplary embodiments. On the other hand, the present invention is not only intended to cover the exemplary embodiments of the present invention, but also covers various alternatives, modifications, equivalents and other embodiments that may be included within the spirit and scope of the present invention as defined by the appended claims.

[0039] The present invention will now be described more fully hereinafter with reference to the accompanying drawings, in which various exemplary embodiments of the present invention are shown. However, these examples may be embodied in various forms and should not be construed as limited to the exemplary embodiments set forth herein. On the contrary, these embodiments are provided so that the disclosure will be thorough and complete, and will fully convey the scope of the present invention to those skilled in the art.

[0040] It should be understood that when an element is referred to as being "on" or "under" another element, the element can be directly on / under the other element, or there can also be one or more intermediate elements.

[0041] When an element is referred to as being "on" or "under", based on the element, it can include "under the element" as well as "on the element".

[0042] In addition, relational terms such as "first", "second", "upper / upper part / above" and "lower / lower part / below" are only used to distinguish one subject or element from another subject or element, and do not necessarily require or imply any physical or logical relationship or order between the subjects or elements.

[0043] Hereinafter, a fuel cell device according to an exemplary embodiment will be described with reference to the accompanying drawings. For ease of description, a Cartesian coordinate system (x-axis, y-axis, z-axis) is used to describe the fuel cell device, but other coordinate systems can also be used to describe it. In the Cartesian coordinate system, the x-axis, y-axis, and z-axis are perpendicular to each other, but the embodiments are not limited thereto. In other words, the x-axis, y-axis, and z-axis can intersect obliquely with each other. In the following description, for ease of description, the x-axis direction is referred to as the "first direction", the y-axis direction is referred to as the "second direction", and the z-axis direction is referred to as the "third direction". The first to third directions can be perpendicular to each other or can intersect obliquely with each other.

[0044] A fuel cell device according to various exemplary embodiments of the present invention may include a fuel cell and a battery monitoring connector.

[0045] A fuel cell to which a battery monitoring connector is installed and connected can be, for example, a polymer electrolyte membrane fuel cell (or proton exchange membrane fuel cell) (PEMFC), which has been the most widely studied as a power source for driving a vehicle. However, the exemplary embodiments are not limited to any specific type of fuel cell.

[0046] The fuel cell may include end plates (press plates or compression plates) and a battery stack.

[0047] Hereinafter, with reference to Figure 1 an example of the battery stack will be described. However, the exemplary embodiments are not limited to any specific type of battery stack.

[0048] Figure 1 is a cross-sectional view of the end plate and the battery stack of the fuel cell.

[0049] The battery stack 122 may include a plurality of unit cells 122-1 to 122-N stacked in a first direction. Here, "N" is a positive integer of 1 or greater and may be in the range of several tens to several hundreds. However, the exemplary embodiments are not limited to any specific value of "N".

[0050] Each unit cell 122-n can generate electric power having a predetermined voltage. Here, 1 ≤ n ≤ N. "N" may be determined according to the power intensity supplied from the fuel cell to the load. Here, the load refers to a part of the vehicle that requires power when the fuel cell device is used in a vehicle.

[0051] Each unit cell 122-n may include a membrane electrode assembly (MEA) 210, gas diffusion layers (GDLs) 222 and 224, gaskets 232, 234 and 236, and separators (or bipolar plates) 242 and 244.

[0052] The membrane electrode assembly 210 includes a structure in which catalyst electrode layers where electrochemical reactions occur are attached to both sides of an electrolyte membrane, and hydrogen ions move through the electrolyte membrane. The membrane electrode assembly 210 may include a polymer electrolyte membrane (or proton exchange membrane) 212, a fuel electrode (hydrogen electrode or anode) 214, and an air electrode (oxygen electrode or cathode) 216. In addition, the membrane electrode assembly 210 may further include a sub-gasket 238.

[0053] The polymer electrolyte membrane 212 is disposed between the fuel electrode 214 and the air electrode 216.

[0054] Hydrogen, which is a fuel in the fuel cell, may be supplied to the fuel electrode 214 through the first separator 242. Air containing oxygen as an oxidant may be supplied to the air electrode 216 through the second separator 244.

[0055] The hydrogen gas supplied to the fuel electrode 214 is decomposed by a catalyst into hydrogen ions (protons) (H+) and electrons (e-). Only the hydrogen ions can selectively pass through the polymer electrolyte membrane 212 and reach the air electrode 216. Meanwhile, the electrons can be conducted through the separators 242 and 244 to the air electrode 216. To achieve the above operations, a catalyst layer can be applied to each of the fuel electrode 214 and the air electrode 216. The movement of the above electrons causes an electric current to flow through an external wire, thereby generating electricity. That is to say, the fuel cell can generate electricity through an electrochemical reaction between hydrogen gas as fuel and oxygen contained in the air.

[0056] In the air electrode 216, the hydrogen ions supplied through the polymer electrolyte membrane 212 and the electrons conducted through the separators 242 and 244 meet the oxygen in the air supplied to the air electrode 216. As a result, a reaction that generates water ("condensate water" or "product water") is induced.

[0057] In some cases, the fuel electrode 214 can be referred to as the anode, and the air electrode 216 can be referred to as the cathode. Alternatively, the fuel electrode 214 can be referred to as the cathode, and the air electrode 216 can be referred to as the anode.

[0058] The gas diffusion layers 222 and 224 are configured to evenly distribute hydrogen gas and oxygen gas as reaction gases and conduct the generated electric energy. For this purpose, the gas diffusion layers 222 and 224 can be disposed on the respective sides of the membrane electrode assembly 210. That is, the first gas diffusion layer 222 can be disposed on the left side of the fuel electrode 214, and the second gas diffusion layer 224 can be disposed on the right side of the air electrode 216.

[0059] The first gas diffusion layer 222 is configured to diffuse and evenly distribute the hydrogen gas supplied as a reaction gas through the first separator 242 and can be conductive. The second gas diffusion layer 224 is configured to diffuse and evenly distribute the air supplied as a reaction gas through the second separator 244 and can be conductive.

[0060] Each of the first gas diffusion layer 222 and the second gas diffusion layer 224 can be a microporous layer in which fine carbon fibers are incorporated. However, the exemplary embodiments are not limited to any specific configuration of the first gas diffusion layer 222 and the second gas diffusion layer 224.

[0061] The gaskets 232, 234, and 236 are configured to maintain the airtightness and clamping pressure of the battery stack at an appropriate level with respect to the reaction gas and the coolant, to disperse stress when stacking the separator plates 242 and 244, and to independently seal the flow paths. Accordingly, since the airtightness and watertightness are maintained by the gaskets 232, 234, and 236, the flatness of the surface adjacent to the battery stack 122 that generates electricity can be ensured. Accordingly, the surface pressure can be evenly distributed on the reaction surface of the battery stack 122. To this end, the gaskets 232, 234, and 236 may be formed of rubber. However, the exemplary embodiments are not limited to gaskets of any specific material.

[0062] The separator plates 242 and 244 are configured to move the reaction gas and the cooling medium and to separate each unit cell from other unit cells. In addition, the separator plates 242 and 244 are configured to structurally support the membrane electrode assembly 210 and the gas diffusion layers 222 and 224 and to collect the generated current and transmit the collected current to the current collector 112.

[0063] The separator plates 242 and 244 may be respectively disposed outside the gas diffusion layers 222 and 224. That is, the first separator plate 242 may be disposed on the left side of the first gas diffusion layer 222, and the second separator plate 244 may be disposed on the right side of the second gas diffusion layer 224.

[0064] The first separator plate 242 is configured to supply hydrogen, which is a reaction gas, to the fuel electrode 214 through the first gas diffusion layer 222. The second separator plate 244 is configured to supply air, which is a reaction gas, to the air electrode 216 through the second gas diffusion layer 224. In addition, each of the separator plates 242 and 244 may form a channel through which a cooling medium (e.g., coolant) can flow. In addition, the separator plates 242 and 244 may be formed of a graphite-based material, a composite graphite-based material, or a metal-based material. However, the exemplary embodiments are not limited to separator plates 242 and 244 of any specific material.

[0065] Figure 1 The end plates 110A and 110B shown in may be disposed at the respective ends of the battery stack 122 and may support and fix the unit cells. That is, the first end plate 110A may be disposed at one end of the battery stack 122, and the second end plate 110B may be disposed at the other end of the battery stack 122.

[0066] Each of end plates 110A and 110B can be configured such that the metal inserts are surrounded by plastic injection molded products. The metal inserts of each of end plates 110A and 110B can have high rigidity to withstand internal surface pressure and can be formed by machining a metal material. For example, each of end plates 110A and 110B can be formed by combining multiple plates. However, the exemplary embodiments are not limited to end plates 110A and 110B of any specific configuration.

[0067] The current collector 112 can be disposed between the battery stack 122 and the inner surfaces 110AI and 110BI of the end plates 110A and 110B facing the battery stack 122. The current collector 112 is configured to collect electric energy generated by the flow of electrons in the battery stack 122 and supply the electric energy to a load using the fuel cell.

[0068] In addition, the first end plate 110A can include a plurality of manifolds (or communication portions) M. Here, the manifolds can include an inlet manifold and an outlet manifold. Hydrogen and oxygen, which are reaction gases required in the membrane electrode assembly 210, can be introduced into the battery stack 122 from the outside through the inlet manifold. The gas or liquid combining the humidified and supplied reaction gas to the battery and the condensed water generated in the battery can be discharged to the outside of the fuel cell through the outlet manifold. The cooling medium can flow into the battery stack 122 from the outside through the inlet manifold and can flow out of the battery stack 122 to the outside through the outlet manifold. As described above, the manifolds allow fluid to flow into and out of the membrane electrode assembly 210.

[0069] Meanwhile, in order to determine the performance of the battery stack 122 and whether the battery stack 122 is operating normally or abnormally, the separators 242 and 244 of each battery can be connected to a control circuit via a fuel cell monitoring connector (or a fuel cell stack voltage monitor (FSVM)) and a wire. In this way, the voltage of each battery can be measured.

[0070] Figure 2 is an overall exploded perspective view of the separator 600 and the battery monitoring connector 300 according to an exemplary embodiment of the present invention. Figure 3 is a partial exploded perspective view of the separator 600 and the battery monitoring connector 300 according to an exemplary embodiment of the present invention. Figure 4A and Figure 4B are respectively Figure 3 a partial joined front view and an exploded front view of the separator 600 and the battery monitoring connector 300 shown. Figure 5A and Figure 5B are respectively Figure 4A a joined cross-sectional view and an exploded cross-sectional view taken along line A-A' in

[0071] For ease of description, among the components of the fuel cell, in Figure 2, Figure 3 , Figure 4A and Figure 4B and Figure 5B only show the separator 600 to which the battery monitoring connector 300 is connected. Although four separators 600 are shown by way of example in Figure 3 , 5A and 5B, the following description applies to all separators 600.

[0072] Since a plurality of unit cells are stacked in the first direction, a plurality of separators 600 included in each unit cell are also spaced apart from each other in the first direction. Here, the separator 600 corresponds to Figure 1 the separators 242 and 244 shown in

[0073] According to an exemplary embodiment of the present invention, the battery monitoring connector 300 can be mounted to the separator 600 of the fuel cell in a second direction intersecting the first direction. As Figure 2 shown, the entire battery monitoring connector 300 can be mounted to all the separators 600.

[0074] Hereinafter, the structure of the separator 600 and the battery monitoring connector 300 engaged therewith will be described.

[0075] Each separator 600 includes an outer surface 600S in which a recessed portion 600H (hereinafter referred to as a "concave connection portion") is formed. That is, in the outer surface of each separator 600, the concave connection portion 600H can be formed in the outer surface 600S of each separator 600 facing the battery monitoring connector 300.

[0076] The battery monitoring connector 300 can include a housing 310 and a convex connection portion (or battery sensing terminal) 320.

[0077] The housing 310 can include a front surface 310F and a rear surface 310B. The front surface 310F corresponds to the surface on which the convex connection portion 320 is provided, and the rear surface 310B corresponds to the surface formed opposite to the front surface 310F in the second direction.

[0078] The convex connection portion 320 can protrude from the front surface 310F of the housing 310 so as to cooperate with the concave connection portion 600H. In this way, the convex connection portion 320 can make surface contact with the outer surface 600IS of the separator 600 within the concave connection portion 600H. That is, the convex connection portion 320 can be not provided between the separators 600, and the outer surface 320S of the convex connection portion 320 can make surface contact with the outer surface 600IS of the separator 600.

[0079] Therefore, according to an exemplary embodiment of the present invention, the convex connecting portion 320 and the partition 600 do not overlap each other in the first direction.

[0080] When the housing 310 moves in the second direction as shown by the arrow AR in Figure 4B , the convex connecting portion 320 can be locked and is initially fixed in a state of being engaged with the concave connecting portion 600H by the spring force of the convex connecting portion 320. To this end, the convex connecting portion 320 can be made of an elastic material.

[0081] According to an exemplary embodiment of the present invention, as Figure 5B shown, the outer surface 600IS of the partition 600 that is in surface contact with the convex connecting portion 320 has a first thickness T1 in the first direction. The outer surface 320S of the convex connecting portion 320 that is in surface contact with the outer surface 600IS of the partition 600S has a second thickness T2 in the first direction.

[0082] According to an exemplary embodiment of the present invention, the overlapping portion of the outer surface 600IS including the first thickness T1 and the outer surface 320S of the convex connecting portion 310 including the second thickness T2 that overlap each other in the second direction may have an overlapping thickness T3 in the first direction, and the overlapping thickness may be greater than or equal to half of the first or second thickness T1 or T2. However, the exemplary embodiment is not limited thereto. The reason is that when surface contact is made in a predetermined area between the outer surface 320S and the outer surface 600IS, the battery voltage can be detected more accurately.

[0083] In addition, referring to Figure 4A , the outer surface 600IS in the concave connecting portion 600H of the partition 600 that is in surface contact with the outer surface 320S of the convex connecting portion 320 may have a uniform thickness, and the outer surface 320S of the convex connecting portion 320 that is in surface contact with the outer surface 600IS of the partition 600 may have a uniform thickness. That is, each of the first thickness T1 and the second thickness T2 may be uniform in the first direction. If any one of the first thickness T1 and the second thickness T2 is not uniform, the area of the contact portion CP between the outer surface 320S and the outer surface 600IS may be reduced. Therefore, according to an exemplary embodiment of the present invention, since the thicknesses T1 and T2 are uniform, the area of the contact portion CP can be ensured, as shown in Equation 1 below, so that the battery monitoring connector 300 can more accurately detect the state of the unit cell.

[0084] [Equation 1]

[0085] TA = T1XL

[0086] Here, TA represents the contact area between the outer surface 320S of the convex connection part 320 and the outer side surface 600IS of the partition plate 600, T1 represents the thickness of the outer side surface 600IS of the partition plate 600, and L represents the contact length between the outer surface 320S and the outer side surface 600IS.

[0087] According to an exemplary embodiment of the present invention, as Figure 6A shown, the concave connection part 600H1 of the partition plate 600A may have a V shape. In this case, the convex connection part 320A of the battery monitoring connector 300A also has a V shape, which is the same as the shape of the concave connection part 600H1.

[0088] According to another exemplary embodiment of the present invention, as Figure 6B shown, the concave connection part 600H2 of the partition plate 600B may have a rectangular shape. In this case, the convex connection part 320B of the battery monitoring connector 300B also has a rectangular shape, which is the same as the shape of the concave connection part 600H2.

[0089] According to various exemplary embodiments of the present invention, as Figure 6C shown, the concave connection part 600H3 of the partition plate 600C may have an arc shape. In this case, the convex connection part 320C of the battery monitoring connector 300C also has an arc shape, which is the same as the shape of the concave connection part 600H3.

[0090] Figure 6A , Figure 6B and Figure 6C The shapes of the concave connection part 600H and the convex connection part 320 shown in are given as examples, and the exemplary embodiments are not limited thereto. That is, when sufficient contact area is ensured between the concave connection part 600H and the convex connection part 320 and their surface contact is stably maintained, they may have various cross-sectional shapes.

[0091] Figure 7A is a front view of an exemplary embodiment of the membrane electrode assembly 210A, Figure 7B is a front view of an exemplary embodiment of the partition plate. Here, the membrane electrode assembly 210A corresponds to Figure 1 the exemplary embodiment of the membrane electrode assembly 210 shown.

[0092] Referring to Figure 7A and Figure 7B, each of the membrane electrode assembly 210A and the separator 600 may include manifolds M1, M2, M3, M4, M5, and M6 formed to have the same shape and the same position as the manifolds of the end plate 110A. Here, the manifolds M1, M2, M3, M4, M5, and M6 may include inlet manifolds M1, M2, and M4 and outlet manifolds M3, M5, and M6. Hydrogen and oxygen, which are reaction gases required in the membrane electrode assembly 210A, may be introduced into the fuel cell stack from the outside of the fuel cell stack 122 through the inlet manifolds M1 and M4. The gas or liquid combined with the humidified and supplied reaction gases and the condensed water generated in the fuel cell may be discharged to the outside of the fuel cell through the outlet manifolds M3 and M6. In addition, the cooling medium may flow into the fuel cell stack 122 from the outside through the inlet manifold M2 and may flow out through the outlet manifold M5. In this way, the manifolds M1, M2, M3, M4, M5, and M6 allow fluids to flow into and out of the membrane electrode assembly 210A.

[0093] In the present case, the membrane electrode assembly 210A included in the unit cell may further include a reaction surface RS and a sub-gasket 610.

[0094] The reaction surface RS is a portion provided at the central portion of the membrane electrode assembly 210A, and the sub-gasket 610 may be provided to surround the reaction surface RS.

[0095] The sub-gasket 610 corresponds to Figure 1 the exemplary embodiment of the sub-gasket 238 shown.

[0096] According to an exemplary embodiment of the present invention, the sub-gasket 610 may include a film-type insulating material (e.g., polyethylene naphthalate (PEN) film). However, the exemplary embodiment is not limited thereto.

[0097] The PEN film has a rigid molecular chain structure, which is one of the important properties of polyester films. Therefore, compared with PET films, the PEN film has excellent tensile strength, impact strength, and breaking strength, has a suitable elongation rate, and has a relatively small thickness. In addition, the PEN film has excellent thermal dimensional stability compared with PET films, and has higher electrical insulation, dielectric constant, and dielectric breakdown voltage compared with PET films. In addition, the extraction amount of oligomers in the PEN film is extremely small, and it has excellent oil resistance, chemical resistance, hydrolysis resistance, gas barrier property, and radiation resistance. Therefore, the PEN film has excellent mechanical, thermal, electrical, and chemical properties.

[0098] Referring to Figure 5A and Figure 5B, the sub-gasket 610 is disposed between two adjacent ones of the plurality of partitions (hereinafter referred to as "first and second partitions"), and the convex connecting portion 320 includes two convex connecting portions (hereinafter referred to as "first and second convex connecting portions") that are in surface contact with the first and second partitions, respectively.

[0099] The sub-gasket 610 may include a first portion P1 and a second portion P2.

[0100] The first portion P1 is a portion disposed between the first and second partitions and spaced apart from the first and second partitions in a first direction.

[0101] The second portion P2 is a portion extending from the first portion P1 toward the battery monitoring connector 300 in a second direction, and is disposed between the first and second convex connecting portions 320 while being spaced apart from the first and second convex connecting portions 320 in the first direction.

[0102] In addition, according to an exemplary embodiment of the present invention, as Figure 7B shown, the concave connecting portion 600H may be disposed near the fifth manifold M5. However, the exemplary embodiment is not limited thereto. That is, according to another exemplary embodiment of the present invention, the concave connecting portion 600H may be disposed near the fourth or sixth manifold M4 or M6.

[0103] Alternatively, the concave connecting portion 600H may be formed near the first, second, and third manifolds M1, M2, and M3 to cooperate with the convex connecting portion 320.

[0104] Figure 8A is an exploded perspective view of a fuel cell device according to another exemplary embodiment of the present invention, Figure 8B is Figure 8A the assembled perspective view of the fuel cell device shown.

[0105] Figure 8A and Figure 8B The fuel cell device shown in may include first and second end plates 110A and 110B, a fuel cell stack 122, and a fixing frame 500.

[0106] Figure 8A and Figure 8B The first and second end plates 110A and 110B and the fuel cell stack 122 shown in correspond to the first and second end plates 110A and 110B and the fuel cell stack 122 shown in Figure 1 respectively. Accordingly, the same components are denoted by the same reference numerals, and repeated description thereof will be omitted.

[0107] As described above, the male coupling part 320 is preliminarily fixed to the female coupling part 600H by the spring force of the male coupling part 320. However, when the fuel cell device moves, the male coupling part 320 may be separated from the female coupling part 600H. Thus, according to an exemplary embodiment of the present invention, the fixing frame 500 is configured to secondarily fix and support the male coupling part 320 so that the male coupling part 320 is not separated from the female coupling part 600H.

[0108] Referring to Figure 4B , Figure 8A and Figure 8B , the fixing frame 500 is disposed on the rear surface 310B of the housing 310 to support the housing 310.

[0109] According to an exemplary embodiment of the present invention, the fixing frame 500 may further include a support part 502 and engaging parts 504 and 506.

[0110] The support part 502 is disposed on the rear surface 310B of the housing 310. In order to prevent the male coupling part 320 from being separated from the female coupling part 600H, the support part 502 may be disposed to overlap the rear surface 310B of the housing 310 in a second direction.

[0111] The engaging parts 504 and 506 may be formed at two ends of the support part 502 along a first direction and may be engaged to the end plates 110A and 110B. That is, the first engaging part 504 may be formed at one end of the support part 502 and may be engaged to the first end plate 110A, and the second engaging part 506 may be formed at the other end of the support part 502 and may be engaged to the second end plate 110B.

[0112] For example, the first and second engaging parts 504 and 506 may be respectively fixed to the first and second end plates 110A and 110B with screws. That is, the second engaging part 506 may include a first through hole SH1 and a second through hole SH2, and a first screw SC1 is fastened through the first through hole SH1, and a second screw SC2 is fastened through the second through hole SH2. The first screw SC1 may be fastened to the second end plate 110B through the first through hole SH1, and the second screw SC2 may be fastened to the second end plate 110B through the second through hole SH2. Similarly, the first engaging part 504 may also include a through hole, and a screw is fastened through the through hole and may be engaged to the first end plate 110A through the screw.

[0113] In addition, the fuel cell device may further include a control circuit 400. To determine the performance of the battery stack 122 and whether the battery stack 122 is operating normally or abnormally, the voltage of each cell can be measured by connecting the separators 242 and 244 of each cell to the control circuit 400 via a battery monitoring connector (or a fuel cell stack voltage monitor (FSVM)) 300 and wires. The control circuit 400 may be a circuit including a measuring device and an electronic control unit that operates the fuel cell in the vehicle. That is, the control circuit 400 is connected to the battery monitoring connector 300.

[0114] For this purpose, for example, as Figure 4B shown, the wire W may be arranged to pass through the housing 310, and the wire W includes one end connected to the male connection portion 320 and the other end connected to the control circuit 400.

[0115] Optionally, the male connection portion 320 and the control circuit 400 may be connected to each other in a board-to-board connection manner. The exemplary embodiments are not limited to any specific connection structure of the male connection portion 320 and the control circuit 400.

[0116] According to an exemplary embodiment of the present invention, as Figure 8A and 8B shown, the control circuit 400 may be arranged between the rear surface 310B of the housing 310 and the fixed frame 500.

[0117] Hereinafter, the fuel cell device according to the comparative example and the fuel cell device according to the exemplary embodiment of the present invention will be compared and described.

[0118] An example of the fuel cell device according to the comparative example is included in Korean Patent Registration No. 10-1337937, and the included comparative example and the exemplary embodiment of the present invention will be compared and described below.

[0119] In the case of the fuel cell device according to the comparative example, "separator tabs" are formed on the separator, and a connector for measuring the cell voltage is connected to the separator tabs to detect the cell voltage. When a plurality of unit cells are stacked, the separator tabs are aligned. As shown in FIG. 14 of Korean Patent Registration No. 10-1337937, the connector for measuring the cell voltage is connected between the separator tabs to detect the cell voltage. However, with the advancement of fuel cell stack technology, narrow-pitch fuel cell stacks are being developed, and thus, the wall of the connector for measuring the cell voltage has become thinner. This has led to problems such as an increase in the difficulty of injection molding of the connector for measuring the cell voltage, difficulty in mounting the connector for measuring the cell voltage to the separator tabs, and difficulty in aligning the separator tabs during mass production of the fuel cell stack. In the case of the comparative example, since the separator is formed of a thin steel plate, the separator is easily bent, resulting in poor assemblability. In addition, since the gap in the housing into which the separator tabs are inserted is very narrow, if the connector for measuring the cell voltage is even slightly distorted, it is impossible to mount the connector for measuring the cell voltage. Therefore, the overall assemblability is very poor.

[0120] In contrast, according to an exemplary embodiment of the present invention, the convex connection portion 320 of the cell monitoring connector 300 makes surface contact with the outer surface 600IS of the separator 600, rather than being inserted between the separator tabs. That is, in the comparative example, the separator tabs are formed on the outside of the separator, while in the exemplary embodiment of the present invention, a recess is formed on the outside of the separator 600 as a concave connection portion 600H. Therefore, the exemplary embodiment of the present invention can improve the assemblability of the narrow-pitch fuel cell stack.

[0121] In addition, in the case of the comparative example, the connection terminal of the connector for measuring the cell voltage that engages with the separator tab has a complex structure, such as a wire clamp (or cylinder) configured to fix a wire.

[0122] In contrast, in the case of the exemplary embodiment of the present invention, the convex connection portion 320 corresponding to the connection terminal of the comparative example protrudes from the housing 310 and makes surface contact with the outer surface 600IS of the separator 600. That is, the exemplary embodiment has a simple connection structure.

[0123] In addition, in the case of the comparative example, after the connector for measuring the cell voltage is fixed to the separator tab, a connector position assurance device (CPA) is used to prevent the connector for measuring the cell voltage from separating. In contrast, in the case of the exemplary embodiment of the present invention, the spring force of the convex connection portion 320 and the fixing frame 500 prevent the convex connection portion 320 from separating from the concave connection portion 600H.

[0124] In addition, in the case of the comparative example, a terminal position assurance device (TPA) is required to guide the connection terminal to the correct position when assembling the connection terminal to the housing and to increase the terminal holding force.

[0125] In contrast, in the case of the exemplary embodiment of the present invention, since the male connection portion 320 connected to the wire W is connected to the outer surface 600IS of the partition 600, the TPA used in the comparative example is not required.

[0126] In addition, in the case of the comparative example, the partitions are grouped into a predetermined number of partition groups, and a plurality of connectors for measuring the battery voltage are respectively installed in the partition groups. For example, if the number of partitions is 200, each connector for measuring the battery voltage is installed in a partition group including ten partitions. In other words, a total of twenty connectors for measuring the battery voltage are sequentially installed in the partition groups.

[0127] In contrast, in the case of the exemplary embodiment of the present invention, as Figure 2 shown, the male connection portion 320 can be simultaneously installed in the plurality of female connection portions 600H of all the partitions 600.

[0128] As described above, in the case of the exemplary embodiment of the present invention, since the battery monitoring connector has a simple structure, compared with the comparative example, the assembly process can be simplified, the production cost can be reduced, and the worker convenience can be improved. For example, in the comparative example, it takes about 10 to 30 minutes to connect the connector for measuring the battery voltage to the partition, while in the exemplary embodiment of the present invention, it takes about 1 to 2 minutes to connect the battery monitoring connector to the outer surface 600IS of the partition. That is to say, the exemplary embodiment of the present invention can greatly reduce the assembly process time.

[0129] In addition, in the case of the exemplary embodiment of the present invention, since the sub-gasket 610 having insulating properties is provided between the male connection portions 320, good electrical insulation can be obtained.

[0130] It is obvious from the above description that in the fuel cell device according to the exemplary embodiment of the present invention, since the battery monitoring connector has a simple structure, the assembly process can be simplified, the production cost can be reduced, and the worker convenience can be improved.

[0131] However, the effects achievable by the present invention are not limited to the above effects, and those skilled in the art will clearly understand other effects not mentioned herein from the above description.

[0132] The above various embodiments can be combined with each other without departing from the scope of the present invention, unless they are incompatible with each other.

[0133] In addition, for any element or process not described in detail in any of the various exemplary embodiments of the present invention, unless otherwise stated, reference may be made to the description of the element or process with the same reference numeral in another exemplary embodiment of the present invention.

[0134] In addition, terms related to a control device such as "controller", "control device", "control unit", "control apparatus", "control module", "control circuit", or "server" refer to a hardware device including a memory and a processor configured to execute one or more steps interpreted as an algorithmic structure. The memory stores the algorithmic steps, and the processor executes the algorithmic steps to perform one or more processes of the method according to the various exemplary embodiments of the present invention. The control device according to the exemplary embodiments of the present invention may be implemented by a non-volatile memory and a processor, the non-volatile memory being configured to store algorithms for controlling the operations of various components of a vehicle or data regarding software commands for executing the algorithms, the processor being configured to use the data stored in the memory to perform the operations described above. The memory and the processor may be separate chips. Alternatively, the memory and the processor may be integrated in a single chip. The processor may be implemented as one or more processors. The processor may include various logic circuits and arithmetic circuits, may be configured to process data according to a program provided from the memory, and may be configured to generate a control signal according to the processing result.

[0135] The control device may be at least one microprocessor operated by a predetermined program, and the predetermined program may include a series of commands for executing the methods included in the above various exemplary embodiments of the present invention.

[0136] In the various exemplary embodiments of the present invention, each of the above operations may be performed by the control device, and the control device may be configured by a plurality of control devices or an integrated single control device.

[0137] In the exemplary embodiments of the present invention, a vehicle may be referred to based on the concept including various transportation means. In some cases, a vehicle may be interpreted based on the concept including not only various land transportation means such as cars, motorcycles, trucks, and buses traveling on roads but also various transportation means such as airplanes, drones, ships, etc.

[0138] For the purposes of explanation and to define the appended claims precisely, the terms "above", "below", "inside", "outside", "upper", "lower", "upward", "downward", "front", "rear", "inner", "outer", "inward", "outward", "inner side", "outer side", "forward" and "backward" are used to describe these features of the exemplary embodiments with reference to the positions of the features shown in the drawings. It should also be understood that the term "connected" or its derivatives refer to both direct and indirect connections.

[0139] The term "and / or" can include combinations of multiple related listed items or any one of multiple related listed items. For example, "A and / or B" includes all three cases, namely "A", "B", and "A and B".

[0140] In an exemplary embodiment of the present invention, "at least one of A and B" can refer to "at least one of A or B" or "at least one of a combination of at least one of A and B". In addition, "one or more of A and B" can refer to "one or more of A or B" or "one or more of a combination of one or more of A and B".

[0141] In this specification, unless otherwise specified, singular expressions include plural expressions, unless the context clearly indicates otherwise.

[0142] In an exemplary embodiment of the present invention, it should be understood that terms such as "comprising" or "having" are intended to indicate the presence of the features, quantities, steps, operations, elements, components or combinations thereof described in the specification, and do not exclude the possibility of adding or existing one or more other features, quantities, steps, operations, elements, components or combinations thereof.

[0143] According to an exemplary embodiment of the present invention, components can be combined with each other to form one component, or some components can be omitted.

[0144] For purposes of illustration and description, the foregoing description of specific exemplary embodiments of the present invention has been presented. They are not exhaustive, nor are they intended to limit the present invention to the precise forms disclosed, and obviously, many modifications and variations are possible in light of the above teachings. The exemplary embodiments were chosen and described in order to explain certain principles of the present invention and its practical applications, so that others skilled in the art can make and utilize various exemplary embodiments of the present invention and their various alternatives and variations. The scope of the present invention is intended to be defined by the appended claims and their equivalents.

Claims

1. A fuel cell device, comprising: A fuel cell, which includes a fuel cell stack, and the fuel cell stack includes a plurality of unit cells stacked in a first direction; And A battery monitoring connector, which is mounted on the fuel cell along a second direction intersecting with the first direction, Wherein, the fuel cell includes a plurality of separators, and the plurality of separators are included in each of the unit cells and are spaced apart from each other in the first direction, Each separator includes an outer surface, and a first connection portion is formed in the outer surface in a recessed manner, The battery monitoring connector includes: A housing; and A second connection portion, which protrudes from the housing to cooperate with the first connection portion and makes surface contact with the outer surface of each separator within the first connection portion.

2. The fuel cell device according to claim 1, wherein, The second connection portion is locked in a state of cooperating with the first connection portion by the spring force of the elastic second connection portion.

3. The fuel cell device according to claim 1, wherein, The housing includes: A front surface, on which the second connection portion is provided; and A rear surface, which is formed opposite to the front surface in the second direction, The fuel cell further includes end plates provided at corresponding ends of the fuel cell stack.

4. The fuel cell device according to claim 3, further comprising: A fixing frame, which is provided on the rear surface of the housing and supports the housing, Wherein, the fixing frame includes: A supporting portion, which is provided on the rear surface of the housing; and Engaging portions, which are formed at a first end portion and a second end portion of the supporting portion along the first direction to engage with the end plates.

5. The fuel cell device according to claim 4, further comprising: A control circuit, which is connected to the battery monitoring connector, Wherein, the control circuit is provided between the rear surface of the housing and the fixing frame.

6. The fuel cell device according to claim 1, wherein, Each unit cell includes a membrane electrode assembly, The membrane electrode assembly includes: A reaction surface, which is provided at a central portion of the membrane electrode assembly; and A sub-gasket, which is provided around the reaction surface.

7. The fuel cell device according to claim 6, wherein, The sub-gasket is provided between a first separator and a second separator adjacent to each other among the plurality of separators, The second connection portion includes one second connection portion and another second connection portion formed to make surface contact with the first separator and the second separator respectively, The sub-gasket includes: A first portion, which is provided between the first separator and the second separator and is spaced apart from the first separator and the second separator in the first direction; and A second portion, which extends from the first portion in the second direction and is provided between the one second connection portion and the another second connection portion and is spaced apart from the one second connection portion and the another second connection portion in the first direction.

8. The fuel cell device according to claim 6, wherein The sub-gasket includes a film-type insulating material.

9. The fuel cell device according to claim 6, wherein, The sub-gasket includes a polyethylene naphthalate film.

10. The fuel cell device according to claim 1, wherein, The outer surface of each separator making surface contact with the second connection portion has a first thickness in the first direction, The second connecting portion in surface contact with the outer surface of each separator has a second thickness in the first direction.

11. The fuel cell device according to claim 10, wherein A portion where the outer surface having the first thickness and the second connecting portion having the second thickness overlap each other in the second direction includes an overlapping thickness in the first direction, The overlapping thickness is greater than or equal to half of the first thickness or the second thickness.

12. The fuel cell device according to claim 10, wherein The outer surface in surface contact with the second connecting portion within the first connecting portion of each separator has a uniform thickness, The second connecting portion in surface contact with the outer surface of each separator has a uniform thickness.

13. The fuel cell device according to claim 1, wherein, The first connecting portion includes a V shape, a rectangle, or an arc shape.

14. The fuel cell device according to claim 1, wherein, The second connecting portion and each separator do not overlap each other in the first direction.

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