US-20260128329-A1 - GASKET FOR REINFORCING SURFACE PRESSURE AND SEPARATOR ASSEMBLY INCLUDING SAME

Abstract

A gasket for reinforcing surface pressure on a separator assembly includes bridges aligned with piercing holes along sealing regions. Its double-uneven structure is designed to accommodate thickness or shape variations, offsetting shrinkage and improving sealing force. By placing bridges within troughs formed by protrusions, the gasket ensures consistent sealing around both reaction and cooling surfaces. Different bridging dimensions are provided for distinct manifold configurations or injection molding gate positions, allowing optimized reinforcement of seal lines, even at partial manifolds or around piercing holes. Ultimately, this design enhances reliability and uniform surface pressure distribution, reducing the risk of leakage.

Inventors

• Yeong Hoon Jeong
• Seung Hun Han
• Duk Hoon Kwon

Assignees

• HYUNDAI MOTOR COMPANY
• KIA CORPORATION

Dates

Publication Date

20260507

Application Date

20250128

Priority Date

20241105

Claims (20)

1. 1 . A gasket for reinforcing surface pressure, disposed on a separator comprising at least one piercing hole provided along a line where sealing is required, the gasket comprising: a double uneven structure protruding from the separator; and a bridge provided at a position corresponding to the at least one piercing hole, wherein the bridge is disposed in a trough provided by the double uneven structure.
2. 2 . The gasket of claim 1 , wherein a height of a top of the bridge is less than a height of a top of the double uneven structure based on one surface of the separator.
3. 3 . The gasket of claim 1 , wherein the gasket comprises an upper gasket disposed on a reaction surface of the separator and a lower gasket disposed on a cooling surface of the separator, and the bridge comprises an upper bridge provided to the upper gasket and a lower bridge provided to the lower gasket based on a position of the piercing hole.
4. 4 . The gasket of claim 3 , wherein the upper bridge is thicker than the lower bridge based on a direction in which the gasket extends, or a height of a top of the upper bridge based on the reaction surface of the separator is greater than a height of a top of the lower bridge based on the cooling surface of the separator.
5. 5 . The gasket of claim 1 , wherein the gasket comprises a first gasket disposed between a perimeter of the separator and manifolds through which reaction gases or coolant flow, and a second gasket disposed on a flow path of the reaction gases or coolant discharged from the manifolds or introduced into the manifolds.
6. 6 . The gasket of claim 5 , wherein the bridge comprises a first bridge provided to the first gasket and a second bridge provided to the second gasket.
7. 7 . The gasket of claim 6 , wherein, among a plurality of second bridges provided on the second gasket disposed at a position corresponding to any one of the manifolds, the second bridges disposed at both ends are larger in size than the remaining second bridges.
8. 8 . The gasket of claim 7 , wherein the second gasket comprises a plurality of extensions extending along the flow path of the reaction gases or coolant discharged from the manifolds or introduced into the manifolds, and the second bridges are disposed outside connection points between the second gasket and the two extensions disposed at both ends based on any one of the manifolds.
9. 9 . The gasket of claim 6 , wherein, among a plurality of second bridges provided on the second gasket disposed at a position corresponding to each of coolant manifolds associated with the coolant among the manifolds, at least one second bridge disposed at a central portion of the second gasket is smaller in size than the remaining second bridges.
10. 10 . The gasket of claim 6 , wherein the bridge comprises a third bridge provided at a point of the first gasket connected to the second gasket disposed on the cooling surface of the separator, and the third bridge is larger in size than the first bridge.
11. 11 . A separator assembly having a gasket for reinforcing surface pressure, comprising: a separator comprising a plurality of piercing holes provided along a line where sealing is required; and a gasket comprising a plurality of bridges provided at positions corresponding to the piercing holes, wherein each of the bridges is disposed on a double uneven structure of the gasket protruding from the separator.
12. 12 . The separator assembly of claim 11 , wherein each of the bridges is disposed in a trough provided by the double uneven structure.
13. 13 . The separator assembly of claim 11 , wherein: the piercing holes comprise a first piercing hole disposed between a perimeter of the separator and manifolds through which reaction gases or coolant flow, and a second piercing hole disposed in a direction toward a central area of the separator from the manifolds, and the bridges comprise a first bridge provided at a position corresponding to the first piercing hole and a second bridge disposed at a position corresponding to the second piercing hole.
14. 14 . The separator assembly of claim 13 , wherein, among a plurality of second bridges, the second bridges disposed on the second piercing holes disposed at both ends among a plurality of second piercing holes corresponding to each of the manifolds are larger in size than the remaining second bridges.
15. 15 . The separator assembly of claim 13 , wherein: a third piercing hole is provided in a direction toward the central area of the separator from partial manifolds associated to the reaction gases among the manifolds, the third piercing hole is spaced apart from the partial manifolds compared to the second piercing hole, and among a plurality of second bridges, the second bridges disposed on the third piercing holes disposed at both ends among a plurality of third piercing holes corresponding to each of the partial manifolds are larger in size than the remaining second bridges.
16. 16 . The separator assembly of claim 15 , wherein: a plurality of first piercing holes comprises a fourth piercing hole disposed on an extension line in a direction in which the third piercing holes are arranged, the plurality of the bridges comprise a third bridge provided at a position corresponding to the fourth piercing hole, and the third bridge is larger in size than the first bridge.
17. 17 . The separator assembly of claim 11 , wherein the gasket comprises an upper gasket disposed on a reaction surface of the separator and a lower gasket disposed on a cooling surface of the separator, and an upper bridge disposed on the upper gasket among the bridges is larger in size than a lower bridge disposed on the lower gasket among the bridges.
18. 18 . A separator assembly for reinforcing surface pressure at a piercing hole, comprising: a separator having at least one piercing hole disposed along a sealing region; and a gasket disposed on the separator, the gasket including at least one bridge aligned with the at least one piercing hole, wherein the bridge is configured with a thickness or shape selected to compensate for shrinkage differences or to increase sealing force relative to surrounding portions of the gasket.
19. 19 . The separator assembly of claim 18 , wherein the gasket is formed by an injection molding process having one or more gate locations, and wherein the bridge has a dimension larger or smaller than other bridges of the gasket based on proximity to a gate location to offset thickness variations that occur during injection molding.
20. 20 . The separator assembly of claim 18 , wherein the gasket comprises a double-uneven structure protruding from the separator, and wherein each bridge is at least partially disposed within a trough defined by the double- uneven structure.

Description

CROSS-REFERENCE TO RELATED APPLICATION This application claims, under 35 U.S.C. § 119(a), the benefit of Korean Patent Application No. 10-2024-0154921, filed on Nov. 5, 2024, the entire contents of which are incorporated herein by reference. TECHNICAL FIELD The present disclosure relates to a gasket capable of reinforcing surface pressure through a bridge provided in a portion where surface pressure is weak, and a separator assembly including the same. BACKGROUND A fuel cell is a type of power generation device configured to convert chemical energy of fuel into electrical energy by electrochemical reaction within a stack. It may be used to supply power for industrial, household, and vehicle driving, as well as to power small electronic products such as portable devices. Recently, fuel cells have been gaining broader adoption as a high-efficiency, clean energy source. Each of unit cells that constitute a typical fuel cell stack has a membrane-electrode assembly (MEA) located at the innermost position. The membrane-electrode assembly is composed of a polymer electrolyte membrane able to transport protons, and catalyst layers applied onto respective sides of the electrolyte membrane so that hydrogen and oxygen may react, namely an anode and a cathode. A pair of gas diffusion layers (GDL) is stacked on both outer surfaces of the membrane-electrode assembly, and a separator assembly with a flow field formed to supply fuel and discharge water generated by reaction is disposed on the outer surfaces of the gas diffusion layers with a gasket therebetween. The separator assembly is formed by joining an anode separator disposed on the anode and a cathode separator disposed on the cathode to face each other. The anode separator and the cathode separator are joined and integrated, whereby manifolds communicate with each other and are configured with similar shapes so that the reaction surfaces are disposed at the same position. Also, an end plate is attached to each of the two outermost surfaces of the stacked unit cells to support and secure the components. Gaskets are disposed on the reaction surface and cooling surface of the cathode separator. Each gasket is formed by an injection molding process, and in the cathode separator, a double-sided injection molding process is performed such that gaskets on the reaction surface and the cooling surface are injection molded simultaneously. Piercing holes are formed along lines in which the gaskets are disposed for the double-sided injection molding process. Double-sided injection molding of the cathode separator is implemented by transferring the material provided on one surface of the cathode separator to the other surface of the cathode separator through the piercing holes. However, due to the presence of the piercing holes, a shrinkage difference arises between the gasket placed on these holes and the gaskets elsewhere. Additionally, variations in injection volume after gasket injection molding causes the gasket over the piercing holes to be lower than in height than gaskets in other areas. As a result, the surface pressure at the piercing holes decreases, weakening overall sealing performance. SUMMARY OF THE DISCLOSURE An object of the present disclosure is to provide a gasket capable of reinforcing surface pressure between a gasket and a separator through a bridge provided in a portion where the surface pressure is weak, and a separator assembly including the same. Another object of the present disclosure is to provide a gasket capable of reinforcing surface pressure between a gasket and a separator by providing a relatively large bridge in a portion where the surface pressure is relatively weak in order to eliminate the surface pressure imbalance between the separator and the gasket. An embodiment of the present disclosure provides a gasket for reinforcing surface pressure. In the gasket disposed on a separator including at least one piercing hole provided along a line where sealing is required, the gasket includes a double uneven structure protruding from the separator and a bridge provided at a position corresponding to the at least one piercing hole, and the bridge is disposed in a trough provided by the double uneven structure. In some embodiments, a height of a top of the bridge may be less than a height of a top of the double uneven structure based on one surface of the separator. In some embodiments, the gasket may include an upper gasket disposed on a reaction surface of the separator and a lower gasket disposed on a cooling surface of the separator, and the bridge may include an upper bridge provided to the upper gasket and a lower bridge provided to the lower gasket based on a position of the piercing hole. In some embodiments, the upper bridge may be thicker than the lower bridge based on a direction in which the gasket extends, or a height of a top of the upper bridge based on the reaction surface of the separator may be greater than a height of a top of th