Fuel cell separator with gasket for improved sealing

Abstract

Fuel cell separator (100, 200), comprising: a seal (130, 230) with cooling surface-side and reaction surface-side airtight conduits (135, 134, 235, 234) formed between a manifold section (110, 210) and a passage surface (122, 124, 222, 224) of the fuel cell separator (100, 200); and a seal support portion (138, 139, 238, 239) formed integrally with each of the airtight conduits (134, 135, 234, 235), wherein the seal (130, 230) comprises an airtight sub-conduit (142, 242) connected to, but not abutting against, the reaction surface-side airtight conduit (134b, 234a) in a region of a reaction surface (122, 222) of the separator (100, 200) in which no gas opening (126, 226) is formed, and the airtight sub-conduit (142, 242) is formed in a region of the reaction surface (122, 222) of the separator (100, 200) that coincides with the cooling surface-side airtight conduit (135b, 235a).

Description

BACKGROUND(a) Field of the invention

[0001] The present disclosure relates to a fuel cell separator having a gasket for improved sealing, and more particularly to a fuel cell separator having a gasket that improves the contact pressure thereof. (b) Description of the prior art

[0002] As is well known in the art, a fuel cell stack includes a membrane electrode assembly (MEA) disposed at its innermost side. The MEA includes a polymer electrolyte membrane through which protons can be moved, and catalyst layers, i.e., a cathode (air electrode) and an anode (fuel electrode), deposited on both surfaces of the polymer electrolyte membrane so that hydrogen reacts with oxygen.

[0003] Additionally, the fuel cell stack includes a gas diffusion layer (GDL) and a gasket stacked sequentially on the outer side of the electrolyte membrane, i.e., at the portion where the cathode and anode are disposed; a separator disposed on the outer side of the GDL and formed with a flow path through which fuel is supplied and water generated by the reaction is discharged; and an end plate coupled to the outermost side thereof for supporting and fixing the above components. Accordingly, protons and electrons are generated by the oxidation reaction of hydrogen in the anode of the fuel cell stack. Specifically, the generated protons and electrons move to the cathode through the respective electrolyte membrane and separator.In the cathode, water is produced by the electrochemical reaction of the protons and electrons moving from the anode and oxygen in the air, and electrical energy is generated simultaneously by the flow of electrons.

[0004] In the fuel cell stack, the gasket is attached to the separator to separate each unit cell of the fuel cell stack and functions to independently seal the hydrogen, coolant, and air passages formed on the surface of the separator. Furthermore, to more consistently perform the gasket function, the fuel cell stack is manufactured taking into account the method for attaching the gasket to the separator and the selection of gasket materials.

[0005] In other words, the bonding structure between the separator and the gasket requires a passage seal function to prevent hydrogen from coming into direct contact with air, a sealing function to prevent coolant from coming into contact with hydrogen and air, a seal retaining function to prevent fluids (e.g., air, hydrogen, and coolant) from flowing out to the outside, etc. In addition, the gasket disposed between the separators provides a supporting force between the separators. The gasket can be manufactured integrally with each separator on both surfaces of the separators by injection molding. In particular, the gasket can be manufactured to prevent a working fluid from escaping due to the characteristics of fuel cells in which airtightness (e.g., an airtight seal) is required for a reactant gas and a coolant.

[0006] In connection with the fuel cell separator with the gasket for improved sealing, a prior art device includes gaskets integrated with separators by injection molding, and the gaskets integrated on both surfaces of the separators by injection molding are continuously connected, forming a closed curve. Furthermore, each interface between the entire edge (rim) of each separator and each manifold is formed with a plurality of injection holes through which a gasket injection fluid flows. The gasket injection fluid flows from one surface of the separator to the opposite surface thereof through the injection holes, and thus the gaskets are continuously integrated across both surfaces of the separator by injection molding.

[0007] In particular, the structure of a seal formed on each of reaction and cooling surfaces of a conventional separator will be described with reference to Fig. 1 of the prior art. Each of the reaction surfaces 10 and 10' of a Fig. The separator shown in Figure 1 represents a section where a fuel cell reaction occurs. Manifolds 20, 20', 22, 22', 24, and 24' forming passages for air, coolant, and hydrogen are arranged in the reaction surfaces 10 and 10', and airtight conduits 30a and 30a' are formed on the reaction surface sides to block the movement of the reaction gas and the coolant. A plurality of seal support portions 32a and 32a' are formed in parallel with the airtight conduits 30a and 30a' to be spaced at predetermined intervals. Furthermore, the hydrogen or air introduced from the cooling surfaces 12 and 12' of the separator moves to the reaction surfaces 10 and 10' through gas passage holes 40 and 40'.

[0008] Additionally, each of the cooling surfaces 12 and 12' of the separator represents a section where heat generated by a chemical reaction is removed. Manifolds 20, 20', 22, 22', 24, and 24' are arranged in the cooling surfaces 12 and 12', providing passages for air, coolant, and hydrogen, and airtight conduits 30b and 30b' are formed on the cooling surface side for introducing coolant. A plurality of seal support sections 32b and 32b' are formed in parallel from the airtight conduits 30b and 30b' to be spaced at predetermined intervals.

[0009] As in Fig. As shown in Figure 1, in the gasket, the positions of the cooling surface-side airtight passages 30b and 30b' and the reaction surface-side airtight lines 30a and 30a' are different from each other, and the gasket support portions 32b and 32b' support the load of the gasket. As a result, the contact pressure of each airtight line between the gasket support portions 32b and 32b' may deteriorate, and refrigerant may leak to the air distributors 20 and 20' or the hydrogen distributors 24 and 24'.

[0010] From US 2010 / 0 028 742 A1 and US 2013 / 0 171 543 A1, a fuel cell separator is known, comprising: a gasket having cooling surface-side and reaction surface-side airtight lines formed between a manifold portion and a passage surface of the fuel cell separator; and a gasket support portion formed integrally with each of the airtight lines, wherein the gasket includes a sub-airtight line connected to the reaction surface-side airtight line in a region in which a gas opening is not formed in a region of a reaction surface of the separator corresponding to the cooling surface-side airtight line.

[0011] The above information disclosed in this section is intended only to enhance the understanding of the background of the invention and may accordingly contain information that does not constitute prior art already known to a person skilled in the art in this country. OVERVIEW

[0012] It is therefore an object of the present invention to provide a fuel cell separator with a gasket for improved sealing, which is capable of improving the contact pressure of a cooling surface-side airtight pipe by additionally forming a sub-pipe / partial airtight pipe in a region where a gas opening is not formed at a cooling surface-side position corresponding to the cooling surface-side airtight pipe of the separator.

[0013] The object is achieved by a fuel cell separator having the features of claim 1. Advantageous further developments can be found in the subclaims.

[0014] In one embodiment, a fuel cell separator is provided with a gasket for improved sealing, and the gasket includes cooling surface-side and reaction surface-side airtight passages formed between a manifold portion and a passage surface of the fuel cell separator, and a gasket support portion formed integrally with each of the airtight passages. The gasket includes a secondary airtight passage connected to, but not abutting against, the reaction surface-side airtight passage in a region of a reaction surface of the separator where no gas opening is formed, and the secondary airtight passage is formed in a region of the reaction surface of the separator that coincides with the cooling surface-side airtight passage.

[0015] Further, the gasket may include a sub-airtight air passage as a sub-airtight passage formed on an anode reaction surface of the separator, which is connected to an anode cooling surface-side airtight air passage formed between an air distributor and an anode cooling surface of the separator, in a region where a hydrogen port is not formed in a region of the anode reaction surface corresponding to the anode cooling surface-side airtight air passage. The sub-airtight air passage may have a structure in which tips of gasket support portions formed between the air distributor and the anode reaction surface of the separator are integrally connected, and may extend toward the anode reaction surface.The airtight subsidiary air passage may have a width equal to or greater than one-half of a width of an airtight air passage formed between the air distributor and the anode reaction surface, and equal to or less than twice the width of the airtight air passage.

[0016] Alternatively, the gasket may include a sub-hydrogen airtight passage as a sub-hydrogen airtight passage formed on a cathode reaction surface of the separator, which is connected to a cathode cooling surface-side airtight hydrogen passage formed between a hydrogen distributor and a cathode cooling surface of the separator in a region where an air hole is not formed in a region of the cathode reaction surface corresponding to the cathode cooling surface-side airtight hydrogen passage. The sub-hydrogen airtight passage may have a structure in which tips of gasket support portions formed between the hydrogen distributor and the cathode reaction surface of the separator are integrally connected, and may extend toward the cathode reaction surface.The airtight sub-hydrogen line may have a width equal to or greater than one-half of a width of the airtight hydrogen line formed between the hydrogen distributor and the cathode reaction surface, and equal to or less than twice the width of the airtight hydrogen line. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The above and other features of the present invention will now be described in detail with reference to embodiments thereof illustrated by the accompanying drawings, which are given hereinafter for illustrative purposes only and thus are not limitative of the present invention. In the figures: Fig. 1 is a plan view illustrating a structure of a seal formed on each of the reaction and cooling surfaces of a separator according to the prior art; Fig. 2 is a plan view illustrating a fuel cell separator with a gasket for improved sealing according to an embodiment of the present invention; Fig. 3 is an enlarged view illustrating main portions of the fuel cell separator with a gasket for improved sealing according to the embodiment of the present invention; Fig. 4 is an enlarged view illustrating main portions of a fuel cell separator with a gasket for improved sealing according to another embodiment of the present invention; Fig. 5 is an enlarged view illustrating main portions of a fuel cell separator with a gasket for improved sealing according to yet another embodiment of the present invention; and Fig. 6 is a graph showing the analyzed result of a contact pressure distribution of a cooling surface-side airtight line of each gasket, wherein samples of a separator with the gasket with an airtight sub-line according to the present invention and a separator with the gasket without an airtight sub-line according to the prior art are manufactured to check an improvement in the sealing contact pressure of the fuel cell separator with a gasket according to an embodiment of the present invention.

[0018] It should be noted that the accompanying drawings are not necessarily to scale and are a somewhat simplified representation of various preferred features intended to illustrate the principles of the disclosure. The specific constructional features of the present disclosure as disclosed herein, including, for example, specific dimensions, orientations, locations, and shapes, will be determined in part by the dedicated application and the operating environment. In the figures, reference characters refer to the same or equivalent parts of the present disclosure throughout the individual figures of the drawings. DETAILED DESCRIPTION

[0019] It is understood that the term “vehicle” or “vehicle-” or other equivalent terms as used herein include motor vehicles in general such as passenger cars including sports utility vehicles (SUVs), buses, trucks, various utility vehicles, watercraft including a variety of boats and ships, aircraft and the like, and include hybrid vehicles, electric vehicles, plug-in hybrid electric vehicles, hydrogen-powered vehicles and other alternative fuel vehicles (e.g., fuel derived from sources other than petroleum).

[0020] Although the embodiment is described as using a plurality of units to perform the example process, it is understood that the example processes may also be performed by one or more modules. Furthermore, it is understood that the term controller / controller refers to a hardware device including a memory and a processor. The memory is configured to store the modules, and the processor is specifically configured to execute said modules to perform one or more processes described below.

[0021] The terminology used herein is for the purpose of describing particular embodiments and is not intended to be limiting of the invention. As used herein, the singular forms "a," "an," and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It is further understood that the terms "comprising" and / or "comprising," when used in this specification, describe the presence of the specified features, integers, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more features, integers, steps, operations, elements, components, and / or groups thereof. As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed elements.

[0022] 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 disclosure is described in connection with embodiments, it is to be understood that this description is not intended to limit the disclosure to those embodiments. On the contrary, the disclosure is intended to cover not only the embodiments, but also various alternatives, modifications, equivalents, and other embodiments that may be included within the spirit and scope of the disclosure as defined by the appended claims.

[0023] In a fuel cell separator with a gasket for improved sealing according to an embodiment of the present invention, gaskets may be integrated on both surfaces of a separator by injection molding and may be continuously connected, thereby forming a closed curve. Referring to Fig. 2, fuel cell separators 100 and 200 according to an embodiment of the present invention may include manifold sections 110 and 210 consisting of hydrogen manifolds 112 and 212 and coolant manifolds 114 and 214 formed at both lateral ends of the separators, and air manifolds 116 and 216, respectively. Passage surfaces (e.g., reaction surface and cooling surface) for reaction gas and cooling fluid may be continuously formed in the inner surfaces of the respective separators 100 and 200.

[0024] In particular, the reaction surface (i.e., anode reaction surface) 122 for hydrogen gas and the cooling surface (i.e., anode cooling surface) 124 for a coolant may each be formed on both surfaces of the anode separator 100 facing the anode of the MEA (not shown). The reaction surface (i.e., cathode reaction surface) 222 for air and the cooling surface (i.e., cathode cooling surface) 224 for a coolant may each be formed on both surfaces of the cathode separator 200 facing the cathode of the MEA (not shown).

[0025] A plurality of gas openings (e.g., hydrogen openings) 126 may be arranged in the vertical width direction of the separator 100 between the hydrogen distributor 112, the anode reaction surfaces, and the anode cooling surfaces 122 and 124 formed at both ends of the anode separator 10. A plurality of gas openings (e.g., air openings) 226 may be arranged in the vertical width direction of the separator 100 between the air distributor 216, the cathode reaction surfaces, and the cathode cooling surfaces 222 and 224 formed at both ends of the cathode separator 200. Specifically, the seal, ie, the anode seal 130 provided in the anode separator 100 will be described.

[0026] With reference to Fig. 2, the anode seal 130 provided in the fuel cell separator according to the embodiment of the present invention may include a side passage 132 and airtight passages 134 and 135 formed on the anode reaction surfaces and anode cooling surfaces 122 and 124 of the separator 100, and a coolant guide passage 139c formed on the anode cooling surface 124. The side passage 132 may be integrally formed along the entire edge of the separator 100 on both surfaces thereof to prevent reaction gas or coolant from flowing outward (e.g., being discharged).

[0027] The airtight ducts 134 and 135 may include a reaction surface-side airtight duct 134 extending integrally in the vertical width direction of the separator 100 between the anode reaction surface 122 and the manifold 110 of the separator 100, and a cooling surface-side airtight duct 135 extending in the vertical width direction of the separator 100 between the anode cooling surface 124 and the manifold 110 of the separator 100. Both ends of each of the reaction surface-side airtight duct 134 and the cooling surface-side airtight duct 135 may be integrally connected to the side duct 132.

[0028] Specifically, the reaction surface-side airtight line 134 may include a reaction surface-side airtight hydrogen line 134a extending in the vertical width direction of the separator 100 between the hydrogen distributor 112 and the anode reaction surface 122, a reaction surface-side airtight air line 134b extending integrally in the vertical width direction of the separator 100 between the air distributor 116 and the anode reaction surface 122, and a reaction surface-side airtight coolant line 134c integrally connected between the airtight hydrogen line 134a and the airtight air line 134b and extending in the vertical direction of the separator 100 between the coolant distributor 114 and the anode reaction surface 122.

[0029] In addition, the cooling surface-side airtight line 135 may include a coolant surface-side airtight hydrogen line 135a extending integrally in the vertical width direction of the separator 100 between the hydrogen distributor 112 and the anode cooling surface 124, and a cooling surface-side airtight air line 135b extending integrally in the vertical width direction of the separator 100 between the air distributor 116 and the anode cooling surface 124. The reaction surface side airtight conduit 134 may be formed integrally with a plurality of seal support portions 138 extending from the airtight conduit 134 to the anode reaction surface 122, and the cooling surface side airtight conduit 135 may be formed with a plurality of seal support portions 139 extending from the airtight conduit 135 to the manifold 110.

[0030] The cooling surface-side airtight passage 135 may be formed with a plurality of seal support portions 139a extending from the airtight air passage 135b to the air distributor 116 in the lateral width direction of the separator 100, may be formed with a plurality of seal support portions 139b extending from the hydrogen airtight passage 135a to the hydrogen distributor 112 in the lateral width direction of the separator 100, and may be formed with a plurality of coolant guide passages 139c extending in the lateral width direction of the separator 100 between the anode cooling surface 124 and the coolant distributor 114.

[0031] The plurality of hydrogen openings 126 may be arranged in the vertical width direction between the airtight hydrogen lines 135a and the hydrogen manifold 112, and each of the hydrogen openings 126 may be arranged between the seal support portions 139b. Each of the coolant guide lines 139c may be a seal support portion and may be integrally formed with the airtight coolant line 134c of the anode reaction surface 122 to be arranged on / at the anode cooling surface 124.

[0032] Furthermore, an airtight sub-air passage 142 may be formed in a predetermined region of the anode reaction surface 122 corresponding to the cooling surface-side airtight air passage 135b to improve the contact pressure of the cooling surface-side airtight passage 135. The airtight sub-air passage 142 may be formed integrally with the airtight air passage 134b in a region where the gas openings 126 are not formed in the predetermined region of the anode reaction surface 122 corresponding to the anode cooling surface-side airtight passage 135 (e.g., in an opening-free region). The airtight subsidiary air passage 142 may extend to the inside of the airtight air passage 134b (i.e., extend to the anode reaction surface 122 from the air manifold 116) and may be formed between the airtight air passage 134b and the anode reaction surface 122.

[0033] For example, as in Fig. 2, in the airtight sub-air passage 142, the tips of the seal support portions 138a formed between the air distributor 116 and the anode reaction surface 122 may be integrally connected and may extend linearly in the vertical width direction of the separator 100. In another example, as shown in Fig. 4, an airtight sub-air passage 142-1 may extend from an air distributor 116 to the anode reaction surface 122 at a predetermined distance in the vertical width direction of a separator 100, and may be connected to an airtight air passage 134b through a side passage 132 and a seal support portion 138 formed at the top of the airtight air passage 134b. Specifically, a space portion (e.g., a free area where a seal material is not applied) 143 may be linearly formed in the vertical width direction of the separator 100 between the airtight air passage 134b and the airtight sub-air passage 142-1.

[0034] In another example, as in Fig. 5, an airtight sub-air duct 142-2 may extend to the inside of the separator 100 (i.e., from an air distributor 116 to an anode reaction surface 122) to be formed integrally with an airtight air duct 134b and extend in the vertical width direction of the separator 100. In particular, a space cut (e.g., a free area where a sealing material is not applied) between the airtight air duct 134b and the airtight sub-air duct 142-2 may not be formed. Furthermore, the airtight sub-air duct 142 may be changed in various ways and is not limited to the Fig. 2 to 5 shown forms.

[0035] With reference to Fig. 3, the sub-airtight air passage 142 may have a width (W2) equal to or greater than one-half of the width (W1) of the anode reaction surface-side airtight air passage 134b formed between the air distributor 116 and the anode reaction surface 122, and may be equal to or less than twice the width (W1) of the anode reaction surface-side airtight air passage 134b, but the present invention is not limited thereto. If the width (W2) of the sub-airtight air passage 142 is less than one-half of the width (W1) of the anode reaction surface-side airtight air passage 134b, the moldability of the gasket may deteriorate. If the width (W2) of the sub-airtight air passage 142 exceeds twice the width (W1) of the anode reaction surface-side airtight air passage 134b, a space limitation may occur.

[0036] Furthermore, the gasket in a region (R1) between the gasket support portions 138a between the anode reaction surface-side airtight air passage 134b and the anode reaction surface-side sub-airtight air passage 142 may have a thickness equal to or greater than one-half of the thickness of the gasket in regions other than the above region (R1), and equal to or smaller than the thickness of the gasket in regions other than the above region (R1), but the present invention is not limited to this. If the thickness of the gasket in the region (R1) between the gasket support portions 138a is less than one-half of the thickness of the gasket in regions other than the above region (R1), the injection moldability of the gasket may deteriorate.

[0037] If the thickness of the gasket in the region (R1) between the gasket support portions 138a exceeds the thickness of the gasket in regions other than the above region (R1), the contact pressure may be asymmetrical / unilateral. Specifically, the thickness / strength of the gasket refers to a thickness in the direction in which gaskets 130 are stacked on the separator 100.

[0038] Furthermore, the seal, ie, the cathode seal 230 provided in the cathode separator 200 is described. With reference to Fig. 2, the cathode seal 230 provided in the fuel cell separator according to the embodiment of the present invention may include a side pipe 232 and airtight pipes 234 and 235 formed on the cathode reaction surface and cathode cooling surface 222 and 224 of the separator 200, and a coolant guide pipe 239c formed on the cathode cooling surface 224.

[0039] The side pipe 232 may be integrally formed along the entire edge of the separator 200 on both sides thereof to prevent reaction gas or a coolant from flowing / flowing outward (e.g., being discharged). The airtight pipes 234 and 235 may include a reaction surface-side airtight pipe 234 that extends integrally in the vertical width direction of the separator 200 between the cathode reaction surface 222 and the manifold 210 of the separator 200, and a cooling surface-side airtight pipe 235 that extends in the vertical width direction of the separator 200 between the cathode cooling surface 224 and the manifold 210 of the separator 200. Both ends of the reaction surface-side airtight pipe 234 and the cooling surface-side airtight pipe 235 may be integrally connected to the side pipe 232.

[0040] Specifically, the reaction surface-side airtight line 234 may include a cathode reaction surface-side airtight hydrogen line 234a that extends integrally in the vertical width direction of the separator 200 between the hydrogen distributor and the cathode reaction surface 222, a cathode reaction surface-side airtight air line 234b that extends integrally in the vertical width direction of the separator 200 between the air distributor 216 and the cathode reaction surface 222, and a cathode reaction surface-side airtight coolant line 234c that is integrally connected between the airtight hydrogen line 234 and the airtight air line 234b and that may extend in the vertical width direction of the separator 200 between the coolant distributor 214 and the cathode reaction surface 222.

[0041] Furthermore, the cooling surface-side airtight line 235 may include a cathode cooling surface-side airtight hydrogen line 235a extending integrally in the vertical width direction of the separator 200 between the hydrogen distributor 212 and the cathode cooling surface 224, and a cathode cooling surface-side airtight air line 235b extending integrally in the vertical width direction of the separator 200 between the air distributor 216 and the cathode cooling surface 224. The reaction surface side airtight conduit 234 may be formed integrally with a plurality of seal support portions 238 extending from the airtight conduit 234 to the cathode reaction surface 222, and the cooling surface side airtight conduit 235 may be formed integrally with a plurality of seal support portions 239 extending from the airtight conduit 235 to the manifold 210.

[0042] Specifically, the cooling surface-side airtight passage 235 may be formed with a plurality of seal support portions 239a extending from the airtight air passage 235b to the air distributor 215 in the lateral width direction of the separator 200, and may be formed with a plurality of seal support portions 239b extending from the hydrogen airtight passage 235a to the hydrogen distributor 212 in the lateral width direction of the separator 200, and may be formed with a plurality of coolant guide passages 239c extending in the lateral width direction of the separator 200 between the cathode cooling surface 224 and the coolant distributor 214.

[0043] The plurality of air holes 226 may be arranged in the vertical width direction between the airtight air passages 234a and the air distributor 216, and each of the air holes 226 may be arranged between the seal support portions 238a. Further, each of the coolant guide passages 239c may be a seal support portion formed integrally with the airtight coolant passage 234c of the cathode reaction surface 222 to be arranged on the cathode cooling surface 224.

[0044] Furthermore, an airtight sub-hydrogen passage 242 may be formed in a predetermined region of the cathode reaction surface 222 corresponding to the cathode cooling surface-side airtight air passage 235b to improve the contact pressure of the cathode cooling surface-side airtight passage 235. The airtight sub-hydrogen passage 242 may be formed integrally with the airtight hydrogen passage 234 in a region where the air holes 226 are not formed in the predetermined region of the cathode reaction surface 222 corresponding to the cathode cooling surface-side airtight passage 235. The airtight sub-hydrogen line 242 may extend to the inside of the airtight hydrogen line 234a (i.e., extend to the cathode reaction surface 222 from the hydrogen distributor 212) and may be formed between the airtight hydrogen line 234a and the cathode reaction surface 222.

[0045] For example, as in Fig. 2, in the airtight sub-hydrogen passage 242, the tips of the seal support portions 238a formed between the hydrogen distributor 212 and the cathode reaction surface 222 may be integral and may extend linearly in the vertical width direction of the separator 200. In another example, as shown in Fig. 4, an airtight sub-hydrogen passage 242-1 may extend from a hydrogen distributor to a cathode reaction surface 222 at a predetermined distance in the vertical width direction of a separator 200, and may be connected to an airtight hydrogen passage 234a through a side passage 232 and a seal support portion 238a formed at the tip of the airtight hydrogen passage 234a. Specifically, a space portion (e.g., a free area where a seal material is not applied) 234 may be linearly formed in the vertical width direction of the separator 200 between the airtight hydrogen passage 234a and the airtight sub-hydrogen passage 242-1.

[0046] In another example, as in Fig. 5, an airtight sub-hydrogen line 242-2 may extend to the inside of a separator 200 (i.e., from a hydrogen distributor 212 to a cathode reaction surface 222) to be formed integrally with an airtight hydrogen line 234a and extend in the vertical direction of the separator 200. Specifically, a space portion (e.g., a free area where a sealing material is not applied) is not formed between the airtight hydrogen line 234 and the airtight sub-hydrogen line 242-2. Further, the airtight sub-hydrogen line 242 may be changed in various ways and is not limited to the Fig. 2 to 5 shown forms.

[0047] The auxiliary airtight hydrogen passage 242 may have a width (W2) equal to or greater than one-half of the width (W1) of the cathode reaction surface-side airtight hydrogen passage 234a formed between the hydrogen manifold 212 and the cathode reaction surface 222, and equal to or less than twice the width (W1) of the cathode reaction surface-side airtight hydrogen passage 234a, but the present invention is not limited thereto. If the width (W2) of the auxiliary airtight hydrogen passage 242 is less than one-half of the width (W1) of the cathode reaction surface-side airtight hydrogen passage 234a, the moldability of the gasket may deteriorate. If the width (W2) of the auxiliary airtight hydrogen passage 242 exceeds twice the width (W1) of the cathode reaction surface-side airtight hydrogen passage 234a, a space limitation may occur.

[0048] Furthermore, the gasket in a region (R1) between the gasket support portions 238a between the cathode reaction surface-side airtight air passage 234b and the cathode reaction surface-side auxiliary hydrogen passage 242 may have a thickness equal to or greater than one-half of the thickness of the gasket in regions other than the above region (R1), and equal to or smaller than the thickness of the gasket in regions other than the above region (R1), but the present invention is not limited to this. If the thickness of the gasket in the region (R1) between the gasket support portions is less than one-half of the thickness of the gasket in regions other than the above region (R1), the injection moldability of the gasket may deteriorate.If the thickness of the gasket in the area (R1) between the gasket support portions exceeds the thickness of the gasket in areas other than the above area (R1), the contact pressure of the gasket may be one-sided.

[0049] In particular, to check an improvement in the contact pressure of the seal of the fuel cell separator with a seal according to the present invention after samples of the Fig. 2 (with the seal with the airtight secondary line) and the one shown in Fig. 1 (with the gasket without the secondary airtight line), the contact pressure distribution of the cooling surface-side airtight line of each gasket can be analyzed. As a result, as shown in Fig.6, the contact pressure of the separator with the gasket having the airtight sub-conduit according to the present invention is higher than the contact pressure of the separator with the gasket without the airtight sub-conduit according to the prior art.

[0050] As apparent from the above description, according to a fuel cell separator having a gasket for improved sealing of the present invention, it may be possible to improve deterioration of the contact pressure of an airtight passage between gasket support portions. Furthermore, it may be possible to prevent coolant from being introduced into an air manifold or a hydrogen manifold due to leakage of the coolant at the portion where the contact pressure of the airtight passage deteriorates.

Claims

[1] Fuel cell separator (100, 200), comprising: a seal (130, 230) with cooling surface-side and reaction surface-side airtight conduits (135, 134, 235, 234) formed between a manifold section (110, 210) and a passage surface (122, 124, 222, 224) of the fuel cell separator (100, 200); and a seal support portion (138, 139, 238, 239) formed integrally with each of the airtight conduits (134, 135, 234, 235), wherein the seal (130, 230) comprises an airtight sub-conduit (142, 242) connected to, but not abutting against, the reaction-surface-side airtight conduit (134b, 234a) in a region of a reaction surface (122, 222) of the separator (100, 200) in which no gas opening (126, 226) is formed, and the airtight sub-conduit (142, 242) is formed in a region of the reaction surface (122, 222) of the separator (100, 200) that coincides with the cooling-surface-side airtight conduit (135b, 235a). [2] The fuel cell separator of claim 1, wherein the seal (130) comprises: a sub-airtight air passage (142) as a sub-airtight passage formed on an anode reaction surface (122) of the separator (100), which is connected to an anode cooling surface-side airtight air passage (135b) formed between an air distributor (116) and an anode cooling surface (124) of the separator (100), in a region where a hydrogen opening is not formed in a region of the anode reaction surface (122) corresponding to the anode cooling surface-side airtight air passage (135b). [3] The fuel cell separator according to claim 2, wherein the airtight sub-air passage (142) has a structure in which tips of seal support portions (138) formed between the air distributor (116) and the anode reaction surface (122) of the separator (100) are integrally connected, and extends toward the anode reaction surface (122). [4] The fuel cell separator of claim 1, wherein the seal (130) comprises: a sub-airtight hydrogen line (242) as a sub-airtight line formed on a cathode reaction surface (222) of the separator (200), which is connected to a cathode cooling surface-side airtight hydrogen line (235) formed between a hydrogen distributor (212) and a cathode cooling surface (224) of the separator (200) in a region where an air hole (226) is not formed in a region of the cathode reaction surface (222) corresponding to the cathode cooling surface-side airtight hydrogen line (235). [5] The fuel cell separator according to claim 4, wherein the airtight sub-hydrogen passage (242) has a structure in which tips of seal support portions (238) formed between the hydrogen distributor (212) and the cathode reaction surface (222) of the separator (200) are integrally connected, and extends toward the cathode reaction surface (222). [6] The fuel cell separator according to claim 2, wherein the sub-airtight air passage (142) has a width (W2) that is equal to or greater than one half of a width (W1) of an airtight air passage (134b) formed between the air distributor (116) and the anode reaction surface (122), and that is equal to or less than twice the width (W1) of the airtight air passage (134b). [7] The fuel cell separator according to claim 4, wherein the airtight sub-hydrogen line (242) has a width (W2) that is equal to or greater than one half of a width (W1) of an airtight hydrogen line (234a) formed between the hydrogen distributor (212) and the cathode reaction surface (222), and that is equal to or less than twice the width (W1) of the airtight hydrogen line (234a).

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