GB2582399A

GB2582399A - Laminated gasket for use with fuel cell stack

Info

Publication number: GB2582399A
Application number: GB1914754.5A
Authority: GB
Inventors: Carl Armour Simon; Smithers Stuart
Original assignee: Intelligent Energy Ltd
Current assignee: Intelligent Energy Ltd
Priority date: 2019-10-11
Filing date: 2019-10-11
Publication date: 2020-09-23
Also published as: GB201914754D0

Abstract

A gasket 100’, 100’’ for use with a fuel cell 10 comprises a compliant layer (108, fig 6a) affixed to a structural layer (104, fig 6a). An adhesive layer (112, fig 6a) is disposed between the compliant layer and the structural layer. The gasket is impermeable to hydrogen. The compliant layer can be deformed so that the gasket has a reduced thickness and produces a seal when placed between fuel cell surfaces. The compliant layer preferably comprises ethylene propylene diene terpolymer (EPDM) and/or polyolefin, and the structural layer may be an elastomeric rubber. Other compliant, structural, and/or adhesive layers may be included in the gasket (figs 6b-i). An adhesive layer is preferably provided on the gasket for contact with the fuel cell surface. In this case, a method of affixing the gasket within a fuel cell stack comprises providing the gasket in an uncompressed state, contacting a first fuel cell with the gasket to form a seal between the fuel cell and the gasket, and fixing the gasket to the first fuel cell via the adhesive layer. The gasket can be used within a fuel cell stack to maintain a predetermined gap between adjacent fuel cell plates.

Description

Intellectual Property Office Application No. GII1914754.5 RTM Date:6 December 2019 The following terms are registered trade marks and should be read as such wherever they occur in this document: Viton and Chemours Intellectual Property Office is an operating name of the Patent Office www.gov.uk /ipo

LAMINATED GASKET FOR USE WITH FUEL CELL STACK

TECHNICAL FIELD

[0001] This disclosure generally relates to laminated gaskets for use with fuel cells and fuel cell stacks.

BACKGROUND

[0002] Fuel cells used in various technologies and applications are often arranged in fuel cell stacks, in which the individual fuel cells are housed directly or indirectly adjacent each other. The separate fuel cells may operate independently or as part of an operational unit when housed in a fuel cell stack.

[0003] In existing fuel cell stack arrangements, the spacing or gaps between the adjacent fuel cells is often uneven. This leads to inconsistent flow of fuel cell components through the fuel cell, which results in irregular performance of the fuel cell and, subsequently, the fuel cell stack. Existing gaskets used in fuel cell stacks do not always maintain consistent spacing between the individual fuel cells in the fuel cell stack. The fuel cell stack is assembled and operated under a specific and predetermined pressure. When gaps between fuel cells are inconsistently sized throughout the fuel cell stack, the pressures differ throughout the stack. This is not desirable because, in addition to adversely affecting performance of the fuel cells, this may also lead to failure of the gasket ("blow out"), where the gasket is damaged or dislodged, leading to leaking of the fuel cell components, improper channelling of the components, further changes in the spacing between fuel cells of the stack, and general inability of the fuel cells and/or the fuel cell stack to operate as desired.

[0004] The disclosed solutions in this application are directed to a novel laminated gasket that maintains consistent spacing between fuel cells in the fuel cell stack throughout the fuel cell stack's operation life, which includes when the fuel cell stack is not being operated, being operated at a maximum operational pressure, and any other non-maximum operation pressure. Even when pressure is changed within the fuel cell stack, the spacing between adjacent fuel cells and/or between fuel cells and other components of the stack is maintained constant by the disclosed gaskets. This structure overcomes the problems of existing technology by maintaining consistent operation of the individual fuel cells and the fuel cell stack.

SUMMARY

[0005] Fuel cells used in various technologies and applications are often arranged in fuel cell stacks, in which the individual fuel cells are housed directly or indirectly adjacent each other. The separate fuel cells may operate independently or as part of an operational unit when housed in a fuel cell stack. This disclosure is not limited to a particular mechanism of controlling the operation of fuel cells or fuel cell stacks.

[0006] The fuel cells may be arranged in various layouts and may be controlled in series, in parallel, or in a combination of series and parallel. The individual fuel cells in a fuel cell stack need to be separated from each other, from the housing, and from other components such that the liquids and gases necessary for proper fuel cell operation can flow along their respective flow paths. At the same time, the fuel cell stack has to have seals that prevent the fuel cell liquids and gases from leaking out of the fuel cell stack or cross-contaminating adjacent cells. To properly space adjacent fuel cells from each other and from the housing in the fuel cell stack, a spacer or gasket may be positioned between adjacent fuel cells, between a fuel cell and the housing, or between the fuel cell and another component of the fuel cell stack. The gasket may also function as a sealing element and create a liquid and/or gas seal within the fuel cell stack.

[0007] The gasket may include various materials, and composition of the gasket affects the sealing capabilities of the gasket. Preferably, the materials used for a gasket in a fuel cell or fuel cell stack are compatible with the constituent fuel cell components. Specifically, the gasket should be chemically and physically compatible with the components of a fuel cell stack such that the gasket can function as desired without degrading its structure or affecting its spacing or sealing capabilities. For example, the gasket may he designed to he impermeable to hydrogen. Similarly, the materials of the gasket should he such that they do not negatively affect the performance of the fuel cell during the operational life of the fuel cell. The gasket should he designed such that it will not fail ("blow our) when subjected to the standard expected pressures during operation of the fuel cell or fuel cell stack.

[0008] In sonic aspects, the gasket materials may be produced in advance of the fuel cell fabrication and then used in the construction process. In other aspects, the gasket materials may form part of the fabrication process itself. In some aspects, the materials may include elastomeric materials, and the specific materials selected can depend on various factors, such as, but not limited to, time to manufacture, production cost, material costs, -2 -material compatibility, ease of incorporation in automated manufacturing processes, and/or other considerations.

[0009] In some aspects, where a seal is manufactured for incorporation into a fuel cell stack or system, several aspects may form part of this process, for example: mould tool design, method of manufacture, and/or material type used. These aspects can stymie development, which can increase Lime and costs of implementation. If an alternative solution is employed that utilises simpler manufacturing and implementation techniques then overall manufacture times may be reduced as well as the costs associated with this. In some existing systems, individually moulded parts are produced via processes such as liquid injection or compression moulding. These parts are then used via a "pick and place" technique at the point of use. This type of solution is costly both in terms of manufacture and implementation as it involves the use of significant labour, equipment resource and time at all stages of manufacture.

[0010] In some aspects, the size, dimensions, and/or shape may affect the sealing capabilities of the gasket.

[0011] Existing methods of individually moulding parts via liquid injection or compression moulding are costly and require use of significant labour, equipment resource and time at all stages of manufacture and implementation. Disclosed are aspects of laminated gaskets that utilize low-cost sheet materials that, when combined, yield an effective seal that can be further manufactured or cut into many shapes and sizes. These gaskets can be incorporated into automated and manual manufacturing processes via known mass manufacturing techniques. Also disclosed are methods of manufacturing the gaskets and methods of implementing the gaskets into fuel cell stacks.

[0012] The laminated gaskets disclosed in this application include at least one structural layer and at. least one compliant layer. At least one adhesive layer is in the gasket.

[0013] According to one aspect, the gasket includes a compliant layer affixed to a structural layer. An adhesive layer is disposed between the compliant layer. Optionally, another adhesive layer may be disposed on the other side of the compliant layer opposite the adhesive layer between the compliant and structural layers, on the other side of the structural layer opposite the adhesive layer between the compliant and structural layers, or both.

[0014] According to other aspects, the gasket may include multiple compliant layers, multiple structural layers, or multiple compliant and structural layers.

[0015] According to an aspect of the disclosure, a first compliant layer may be affixed to a first structural layer. A second compliant layer may he affixed to the first structural layer opposite the first compliant layer. An adhesive layer may be disposed between the first structural and first compliant layers and/or between the first structural layer and the second compliant layer. Optionally additional adhesive layers may be disposed on the other side of the first compliant layer opposite the adhesive layer between the first compliant and first structural layers, on the other side of the second compliant layer opposite the adhesive layer between the first structural layer and the second compliant layer, or both.

[0016] According to another aspect, a first compliant layer may be affixed to a first structural layer. A second structural layer may he affixed to the first compliant layer opposite the first structural layer. An adhesive layer may be disposed between the first structural and first compliant layers and/or between the first compliant layer and the second structural layer. Optionally, additional adhesive layers may be disposed on the other side of the first structural layer opposite the adhesive layer between the first compliant and first structural layers, on the other side of the second structural layer opposite the adhesive layer between the first compliant layer and the second structural layer, or both.

[0017] According to another aspect, a first compliant layer may be affixed to a first structural layer. A second structural layer may he affixed to the first compliant layer opposite the first structural layer. A second compliant layer may be affixed to the second structural layer opposite the first compliant layer. An adhesive layer may be disposed between the first structural layer and the first compliant layer, between the first compliant layer and the second structural layer, and/or between the second structural layer and the second compliant layer. Optionally, additional adhesive layers may be disposed on the other side of the first structural layer opposite the adhesive layer between the first compliant and first structural layers, on the other side of the second compliant layer opposite the adhesive layer between the second structural layer and the second compliant layer, or both.

[0018] According to another aspect, a first compliant layer may be affixed to a first structural layer. A second structural layer may be affixed to the first structural layer. An adhesive layer may be disposed between the first compliant layer and the first structural layer, between the first structural layer and the second structural layer, or both. Optionally, an adhesive layer may be disposed on the other side of the first compliant layer opposite the adhesive layer between the first compliant and the first structural layers, on the other side of -4 -the second structural layer opposite the adhesive layer between the first and second structural layers, or both. Optionally, a second compliant layer may he affixed to the second structural layer opposite the first structural layer. An adhesive layer may be disposed between the second compliant layer and the second structural layer. An adhesive layer may be disposed on the other side of the second compliant layer opposite the adhesive layer between the second compliant layer and the second structural layer.

[0019] According to another aspect, a first structural layer may be affixed to a first compliant layer. A second compliant layer may be affixed to the first compliant layer. An adhesive layer may be disposed between the first structural layer and the first compliant layer, between the first compliant layer and the second compliant layer, or both. Optionally, an adhesive layer may be disposed on the other side of the first structural layer opposite the adhesive layer between the first structural and the first compliant layers, on the other side of the second compliant layer opposite the adhesive layer between the first and second compliant layers, or both. Optionally, a second structural layer may he affixed to the second compliant layer opposite the first compliant layer. An adhesive layer may be disposed between the second structural layer and the second compliant layer. An adhesive layer may be disposed on the other side of the second structural layer opposite the adhesive layer between the second structural layer and the second compliant layer.

[0020] According to another aspect, a first structural layer may be affixed to a second structural layer. A first compliant layer may be affixed to a second compliant layer. The first compliant layer may be affixed to the second structural layer. An adhesive layer may he disposed between the first structural layer and the second structural layer, between the second structural layer and the first compliant layer, between the first compliant layer and the second compliant layer, between all of the layers, or between some of the layers. Optionally, an adhesive layer may be disposed on the other side of the first structural layer opposite the adhesive layer between the first structural and the second structural layer, on the other side of the second compliant layer opposite the adhesive layer between the first and second compliant layers, or both.

[0021] According to another aspect, a gasket for use with a fuel cell stack includes a compliant layer, a structural layer fixedly attached to the compliant layer, and an adhesive layer having an adhesive and being disposed between the compliant layer and the structural layer, and being configured to secure the structural layer to the compliant layer. The gasket may be impermeable to hydrogen. Optionally, the compliant layer may include an undeformed configuration defining a first thickness and a deformed configuration defining a second thickness smaller than the first thickness, and the compliant layer is movable between the undeformed and the deformed configurations. Optionally, the structural layer may have a predetermined thickness, the predetermined thickness being the same for when the compliant layer is in the undeformed state and for when the compliant layer is in the deformed state. Optionally, the gasket may include an interface configured to contact a fuel cell in the fuel cell stack and to form a seal between the fuel cell and the gasket. Optionally, the compliant layer may include ethylene propylene diene terpolymer (EPDM) and/or polyolefin. Optionally, the structural layer may he an elastomcric rubber. Optionally, the compliant layer may be a first compliant layer, the structural layer may be a first structural layer, the adhesive layer may be a first adhesive layer, and the gasket may further include a second compliant layer fixedly attached to the first structural layer, a second structural layer fixedly attached to the second compliant layer, a second adhesive layer disposed between the first structural layer and the second compliant layer, and a third adhesive layer disposed between the second compliant layer and the second structural layer. Optionally, the gasket may further include a fourth adhesive layer disposed on the gasket and configured to contact the fuel cell stack. Optionally, the gasket may further include an opening extending therethrough and configured to receive a component of the fuel cell stack. Optionally, the interface configured to contact the fuel cell may include the compliant layer and the structural layer, and the interface is contoured to complement the fuel cell. Optionally, the gasket may have a compressed state defining a first height and an uncompressed state defining a second height greater than the first height. Optionally, the gasket may contact the fuel cell interface when the gasket is in the compressed state.

[0022] According to another aspect, a method of affixing a gasket within a fuel cell stack includes the steps of providing a gasket in the uncompressed state, contacting a first fuel cell with the gasket, such that a seal is formed between the first fuel cell and the gasket, and affixing the gasket to a first fuel cell via one or more of the adhesive layers. The gasket may be according to any of the aspects described above. Optionally the method may include contacting a second fuel cell with the gasket, such that a seal is created between the second fuel cell and the gasket, and compressing the gasket such that the gasket moves from the -6 -uncompressed state to the compressed state, wherein the gasket is disposed between the first fuel cell and the second fuel cell.

BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The present application is further understood when read in conjunction with the appended drawings. For the purpose of illustrating the subject matter, there are shown in the drawings exemplary aspects of the subject matter; however, the presently disclosed subject matter is not limited to the specific methods, devices, and systems disclosed. In the drawings: [0024] Fig. 1 shows an isometric perspective view of a fuel cell stack according to an aspect of the disclosure; [0025] Fig. 2 shows an isometric view of a fuel cell stack with a plurality of fuel cell plates; [0026] Fig. 3 shows an isometric perspective view of a gasket according to an aspect of the disclosure; [0027] Fig. 4 shows a cross-sectional front elevation view of a fuel cell plate with a gasket according to an aspect of the disclosure; [0028] Fig. 5 shows a cross-sectional front elevation view of a fuel cell stack according to an aspect of the disclosure; [0029] Fig. 6a-6i shows aspects of gaskets according to the disclosure; [0030] Fig. 7a shows a top plan view of a fuel cell plate having a gasket according to an aspect of the disclosure; [0031] Fig. 7b shows a top plan view of a fuel cell plate having a gasket according to another aspect of the disclosure; [0032] Fig. 8a shows a top plan view of a gasket according to another aspect of the disclosure; [0033] Fig. 8b shows a side elevation view of the gasket of Fig. 8a; and [0034] Fig. 8c shows a front elevation view of the gasket of Figs. 8a and 8b.

[0035] Aspects of the disclosure will now be described in detail with reference to the drawings, wherein like reference numbers refer to like elements throughout, unless specified otherwise. -7 -

DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

[0036] When values are expressed as approximations by use of the antecedent "about," it will he understood that the particular value forms another embodiment. In general, use of the term "about" indicates approximations that can vary depending on the desired properties sought to be obtained by the disclosed subject matter and is to be interpreted in the specific context in which it is used, based on its function, and the person skilled in the art will be able to interpret it as such. In some cases, the number of significant figures used for a particular value may he one non-limiting method of determining the extent of the word "about." In other cases, the gradations used in a series of values may be used to determine the intended range available to the term "about" for each value. Where present, all ranges are inclusive and combinable. That is, reference to values stated in ranges includes each and every value within that range. Throughout this disclosure, the use of "about" encompasses both approximations and the exact value.

[0037] Gaskets disclosed in this application include at. least one structural layer, at. least one compliant layer, and at least one adhesive layer. The gasket may include a plurality of structural layers, a plurality of compliant layers, and/or a plurality of adhesive layers. The gasket is configured to be placed adjacent to a fuel cell in a fuel cell stack and contact the fuel cell. Another fuel cell may he placed opposite the previous fuel cell with the gasket being between the fuel cells. The gaskets may contact the cathode or the anode plates of the fuel cell. Multiple fuel cells may he arranged in a fuel cell stack having a housing that receives the fuel cells therein. Gaskets may be arranged between adjacent fuel cells. Gaskets may also be arranged in the space between a fuel cell and the housing.

[0038] The at least one compliant layer is elastically deformable and is configured to be compressed by application of a compression force. When the compression force is removed, the compliant layer may return to substantially its original state. The compliant layer may have an uncompressed thickness when no compression force is applied and a compressed thickness when the compression force is applied. The compressed thickness is smaller than the uncompressed thickness. The compliant layer may include a closed-cell foam material. In some aspects, the compliant layer may include ethylene propylene diene terpolymer (EPDM), polyolefin foam, a combination of EPDM and polyolefin foam, or another suitable material. -8 -

[0039] The at least one structural layer is designed to be rigid and substantially oppose compression. The structural layer has a thickness that is designed to remain constant. When the compression force is applied to the at least one structural layer, the thickness of the at last one structural layer remains substantially unchanged. The structural layer may include an elastomeric rubber material. In some aspects, the structural layer may include ethylene propylene diene terpolymer (EPDM). In some aspects, the structural layer may include an FKM fluoroelastomer, for example Viton (owned by The Chemours Company) or a similar material.

[0040] The at least one adhesive layer is designed to fixedly attached one component to another component. Each adhesive layer is configured to engage with the structural layer, the compliant layer, the fuel cell plate, and/or another component of the fuel cell stack, for example the housing. The adhesive layer may vary in size and can range from about 10 pm -about 100 pm, about 20 pm -about 90 pm, about 30 pm -about 80 pm, about 40 pm -about 70 pm, 50 pm -about 60 pm, or a combination of the above ranges. In some aspects, the adhesive layer may be between about 45 pm -55 pm, and for example about 50 pm in thickness. The adhesive layer includes an adhesive component and can include, for example, acrylic. The adhesive layer may include pressure sensitive adhesive, spray adhesive, hot melts, epoxy, or two-part adhesives, or a combination of the above.

[0041] The gasket has at least two configurations. In a first, uncompressed, configuration, the compression force is not applied to the gasket, and the at least one compliant layer of the gasket is uncompressed. When the gasket is in the first configuration, the gasket has a first (or uncompressed) height. In a second, compressed, configuration, the compression force is applied to the gasket, and the at least one compliant layer of the gasket is compressed. When the gasket is in the second configuration, the gasket has a second (or compressed) height that is smaller than the uncompressed height.

[0042] The gasket can he manufactured to have a predetermined uncompressed and compressed height depending on the space into which the gasket is to be placed between adjacent fuel cells or between a fuel cell and a component of the fuel stack, such as the housing. The uncompressed height of the gasket should be greater than the width of the gap into which the gasket is to be placed. The compressed height (also referred to as the working height) should be substantially the same as the width of the gap. It will be appreciated that the actual compressed height should be nominally smaller than the exact width of the gap so as to allow the gasket to fit into the gap.

[0043] The width of the gap may be determined based on the intended use of the fuel cell stack, the number of fuel cells in the fuel cell stack, the fuel cell components to be used (e.g. fuel), or other parameters of the fuel cells and/or fuel cell stack. In some instances, the particular gasket to he used may dictate the desired width of the gap. In some aspects, the width of the gap may range from about 0.5 mm to about 1 mm, from about 1 mm to about 1.5 mm, from about 1.5 mm to about 2 mm, from about 2 mm to about 2.5 mm, from about 2.5 mm to about 3 mm and combinations thereof, such as about 0.5 mm to about 1.5 mm, about 0.5 mm to about 2 mm, about 0.5 mm to about 2.5 mm, about 0.5 mm to about 3 mm, about 1 mm to about 2 mm, about 1 nun to about 2.5 mm, about 1 mm to about 3 mm, about 2 mm to about 3 mm [0044] The ratio of the structural layer (or structural layers) to the rest of the gasket may he determined based on the gap into which the gasket is disposed, the intended operational parameters of the fuel cell stack, and/or the manufacturing materials and methods of manufacturing available. When the gasket is in the second, compressed, configuration, the one or more structural layers account for between about 30% -about 90% of the compressed height of the gasket, about 40% -about 80%, about 50% -about 70%, or a combination of these ranges. The one or more structural layers can account for about 40% -about 50% of the compressed height of the gasket, about 50% -about 60%, about 60% -about 70%, about 70% -about 80%, about 80% -about 90%, or a combination of the above ranges. In some specific aspects, the structural layer or layers account for between about 70% -about 75%, and for example about 72%, of the compressed height of the gasket.

[0045] The fuel cell stack may be designed to have one or more fuel cell plates therein, for example, 1, 2, 3, ... 20, or another suitable number of fuel cells plates. Each fuel cell plate may have one or more channels configured to receive and pass therethrough one or more fluid components of the fuel cell. One or more channels configured to receive and carry a gas therethrough may receive the gas from a gas inlet on the fuel cell stack and allow the gas to travel through the channel and exit through a gas outlet on the fuel cell stack. The gas may he moved from the gas inlet through the gasket to the fuel cell plate. In fuel cell stacks having multiple fuel cell plates, the gas may move through multiple gaskets and be -10-distributed to some or all of the multiple fuel cell plates either evenly or in a predetermined proportion.

[0046] The gasket may include one or more passages extending therethrough to receive the gas and/or other fluid component of the fuel cells. The passage has an inlet opening and an outlet opening opposite the inlet opening. The inlet and the outlet openings are configured to contact or otherwise be fluidly engaged with the one or more channels of the fuel cell configured to receive the gas or other fluid. In some aspects where multiple fuel cell plates and multiple gaskets are arranged, the passages of adjacent gaskets may contact or otherwise be fluidly engaged with a passage of at least one other gasket, for example in a serial arrangement, such that the outlet opening of one gasket fluidly engages with the inlet opening of an adjacent gasket.

[0047] The gasket may have a specific compression ratio determined by the height of the gasket in the first (uncompressed) configuration and the second (compressed) configuration. The ratio of the gasket height in the first configuration to the gasket height in the second configuration may be between about 1:1 -about 3:1, about 1:1-about 2.5:1, about 1:1 -about 2:1, about 1:1 -about 1.5:1. Other suitable ranges may be between about 1.5:1 -about 2:1, about 1.5:1 -about 2.5:1, about 1.5:1 -about 3:1, about 2:1 -about 2.5:1, about 2:1 -about 3:1, about 2.5:1 -about 3:1, or another suitahle ratio. In some aspects, the ratio of the gasket height in the first configuration to the gasket height in the second configuration may also be between about 1.1:1 -about 2:1, about 1.2:1 -about 1.9:1, or about 1.3:1 -about 1.8:1, about 1.4:1 -about 1.7:1, or about 1.5:1 -about 1.6:1.

[0048] Referring to Figs. 1 and 2, a fuel cell stack 1 is shown having a plurality of fuel cell plates 10 therein. The fuel cell stack 1 may include a housing 4 configured to receive, at least in part, the one or more fuel cell plates 10. For reference, coordinates are included to show x-, y-, and z-directions. It will be appreciated that other coordinate labels can he used, and that the coordinates depicted in these figures are for reference and do not indicate absolute orientations. A plurality of gaskets 100 are disposed within the fuel cell stack 1. The fuel cell stack 1 in Figs. 1 and 2 is assembled and shows the gaskets 100 in a second, compressed, configuration. Referring to the coordinate axis provided for these figures, the gaskets arc compressed in the z-direction. It will he appreciated that a fuel cell stack 1 may include a different number of fuel cell plates 10 as described throughout this application, as well as a different number of gaskets 100. In the exemplary aspect depicted in Figs. 1 and 2, the fuel cell stack 1 includes six fuel cell plates 10 and twelve gaskets 100, such that each fuel cell plate 10 contacts at least two gaskets 100, for example one at a gas-inlet side and one at a gas-outlet side.

[0049] Referring to Fig. 3, a gasket 100 is depicted in a first, uncompressed, configuration. A passage 116 extends through the gasket 100 between a first end 120 and a second end 128. The first end 120 defines a first interface 124, and the second end 128 defines a second interface 132. The first and second interfaces 124, 132 are each configured to contact a fuel cell plate 10. The first and second interfaces 124, 132 may be configured to also contact the housing 4. In some aspects, the first interface 124 may contact the fuel cell plate 10 while the second interface 132 may contact the housing 4, or vice versa. The gasket may also be configured such that the first interface 124 contacts the fuel cell plate 10 while the second interface 132 contacts a different fuel cell plate 10 in the same fuel cell stack 1. The gasket 100 includes a wall 136 that may be substantially perpendicular to the first and second interfaces 124, 132. That is, the first and second interfaces 124, 132 may each he parallel to the x-y-plant, as shown in the provided coordinate axis, while the wall 136 may be parallel to the y-z-plane (or to the x-z-plane). The wall 136 may contact the fuel cell plate 10 and may define a contour or shape that corresponds to the shape of the fuel cell plate 10. For example, in the non-limiting aspect shown in Fig. 7a, the wall 136 may be substantially planar to correspond to the planar contour of the fuel cell plate 10. In an alternative non-limiting aspect of Fig. 7b, the wall 136 may have a non-planar, for example a wavy, contour to correspond to the complementary contour of the fuel cell plate 10.

[0050] Referring to Fig. 4, a fuel cell plate 10 is depicted showing two gaskets 100 at either end of the fuel cell plate 10. The gaskets 100 are shown in the first, uncompressed, configuration. Fig. 5 depicts a plurality of fuel cell plates 10 within a fuel cell stack 1. The fuel cell plates 10 are stacked one on top of the other. A plurality of gaskets 100 are disposed within the fuel cell stack 1. When the fuel cell plates 10 are fixedly engaged with one another, the gaskets 100 are in the second, compressed, configuration. For reference, in Fig. 5, uncompressed gaskets are labelled as 100', and compressed gaskets are labelled 100".

[0051] Referring to Figs. 6a-i, various embodiments of gaskets 100 are disclosed. It will he appreciated that these embodiments are not limiting and may he combined with each other. -12-

[0052] Referring to Figs. 6a-6d, a gasket 100 may include a compliant layer 108, a structural layer 104, and an adhesive layer 112 disposed between the compliant layer 108 and the structural layer 104. The adhesive layer 112 fixedly connects the compliant layer 108 to the structural layer 104.

[0053] The gasket 100 may include a plurality of the structural layers 104, compliant layers 108, and/or adhesive layers 112. In some aspects, the gasket 100 includes a first compliant layer 108a, a first structural layer 104a, a first adhesive layer 112a disposed between the first compliant layer 108a and the first structural layer 104a, and a second adhesive layer 112b on the first structural layer 104a opposite the first adhesive layer 112a (Fig. 6b), on the first compliant layer 108 opposite the first adhesive layer 112a (Fig. 6c), or both, wherein the second adhesive layer 112b is on one of the first compliant layer 108 and the first structural layer 104, and a third adhesive layer 112c is on the other of the first compliant layer 108 and the first structural layer 104. Each of the adhesive layers 112a-c may be the same, or they may have different dimensions or adhesive materials and properties.

[0054] Any of the aspects depicted in Figs. 6a-6d may comprise the gasket 100 in its entirety. Alternatively, in some aspects, the gasket 100 may include a combination of the aspects depicted in Figs. 6a-6d and/or a plurality of one or more individual aspects. An adhesive layer 112 may he disposed between adjacent compliant and structural layers 108, 104. In some aspects, an adhesive layer 112 may be disposed on the gasket 100 such that the adhesive layer 112 is between the gasket 100 and the sealing surface when the gasket 100 is placed into the fuel cell stack 1, for example between the gasket 100 and the fuel cell 10 or between the gasket 100 and the housing 4.

[0055] For example, in some aspects, the gasket 100 includes a first compliant layer 108a that is fixedly attached, via an adhesive layer 112, to a first structural layer 104a. The first structural layer 104a is fixedly attached, via another adhesive layer 112, to a second compliant layer 108b. The first compliant, first structural, and second compliant layers 108a, 104a, 108b are stacked one on top of each other in the z-direction. In some aspects, a second structural layer 104h may be fixedly attached, via another adhesive layer 112, to the second compliant layer 108a in the stacked arrangement as depicted in Fig. 6e.

[0056] Referring to Fig. 6f, the gasket 100 may include a first structural layer 104a fixedly attached to a second structural layer 104b via an adhesive layer 112 without a compliant layer 108 between the first and second structural layers 104a, 104b. The gasket -13 -may further include a first compliant layer 108a affixed to the first structural layer 104a, a second compliant layer 108b affixed to the second structural layer 104b, or both.

[0057] In an alternative aspect depicted in Fig. 6g, the gasket 100 may include a first compliant layer 108a fixedly attached to a second compliant layer 108b via an adhesive layer 112 without a structural layer 104 between the first and second compliant layers 108a, 108b. The gasket 100 may further include a first structural layer 104a affixed to the first compliant layer 108a, a second structural layer 104b affixed to the second compliant layer 108b, or both.

[0058] Referring to Figs. 6h-6i, the gasket 100 is shown compressed and in the second configuration. The gasket 100 is disposed between two sealing surfaces and moved from the first (uncompressed) configuration to the second (compressed) configuration such that the gasket 100 fits into the gap 140 defined in the space between the two sealing surfaces. Each of the sealing surfaces may be a fuel cell plate 10, and in some aspects, both sealing surfaces may be fuel cell plates 10 (Fig. 611). In some aspects, one of the sealing surfaces is a fuel cell plate 10 and the other sealing surface is the housing 4 of the fuel cell stack 1 (Fig. 6i).

[0059] It will be appreciated that the above illustrative aspects are exemplary and are not limiting to each other. The specific arrangement of layers in the gasket will depend on the desired use of the gasket. The disclosed gaskets may be used in various applications and are configured to engage multiple surface types, such as fuel cell plates, membrane electrode assembly (MEA) sub-gaskets, or other components of a fuel cell plate or fuel cell stack.

[0060] The gaskets described throughout this application may be manufactured by laminating the different layers (e.g. compliant, structural, adhesive layers) one on top of the other. Once the laminated material is manufactured, the gasket can be further amended by cutting it into the desired dimensions and shapes, for example via rotary knife tools.

[0061] Methods of manufacturing may differ and will depend on the specific gasket parameters that are desired. Generally, manufacturing includes the steps of forming a first structural layer, forming a first compliant layer on top of the first structural layer, and fixedly sealing the first compliant layer to the first structural layer via a first adhesive layer. The method may include a discrete step of applying an adhesive layer to the first structural layer -14-before forming the first compliant layer. Alternatively, the adhesive layer may be applied to the first compliant layer, which is then affixed to the structural layer.

[0062] In some aspects, a second structural layer may be affixed via another adhesive layer to the first compliant layer or to the first structural layer. A second compliant layer may be affixed via another adhesive layer to the first compliant layer or to the first structural layer. Depending on the desired gasket, one or more of the above steps may be repeated to further form and affix additional structural and/or compliant layers.

[0063] To place the gasket into a fuel cell stack, the gasket can be inserted into the gap defined by the space between the two sealing surfaces, for example between two fuel cell plates or between a fuel cell plate and the housing of the fuel cell stack. The gasket in the first configuration is uncompressed is has a height that is greater than the gap between the sealing surfaces. To insert the gasket into the gap, a compressive force is applied to the gasket in the z-direction such that the gasket is compressed into the second configuration until the compressed height of the gasket is at least nominally smaller than the gap. The compressed gasket is then inserted into the gap, and the applied compressive force is removed. The gasket is held in a compressed state by the two sealing surfaces between which it is disposed, such that the sealing surfaces now apply a normal force to the gasket that is reactionary to the pressure applied by the compressed gasket onto each of the two sealing surfaces. When the gasket is moved from the uncompressed configuration to the compressed configuration, only the one or more compliant layers are deformed, while the one or more structural layers are not deformed.

[0064] The disclosed gaskets and methods of manufacturing present several advantages over existing solutions. The gaskets disclosed throughout this application maintain consistent spacing between fuel cells in the fuel cell stack throughout the fuel cell stack's operation life, which includes when the fuel cell stack is not being operated, being operated at a maximum operational pressure, and any other non-maximum operation pressure. Even when pressure is changed within the fuel cell stack, the spacing between adjacent fuel cells and/or between fuel cells and other components of the stack is maintained constant by the disclosed gaskets.

[0065] In existing fuel cell stack arrangements, the spacing or gaps between the adjacent fuel cells is often uneven. This leads to inconsistent flow of fuel cell components through the fuel cell, which results in irregular performance of the fuel cell and, -15-subsequently, the fuel cell stack. Existing gaskets used in fuel cell stacks do not always maintain consistent spacing between the individual Cud cells in the fuel cell stack. The fuel cell stack is assembled and operated under a specific and predetermined pressure. When gaps between fuel cells are inconsistently sized throughout the fuel cell stack, the pressures differ throughout the stack. This is not desirable because, in addition to adversely affecting performance of the fuel cells, this may also lead to failure of the gasket ("blow out"), where the gasket is damaged or dislodged, leading to leaking of the fuel cell components, improper channelling of the components, further changes in the spacing between fuel cells of the stack, and general inability of the fuel cells and/or the fuel cell stack to operate as desired.

[0066] Additional exemplary scenarios are described below in addition to the above disclosure. Each of these scenarios can be stand-alone or can be combined with one, multiple, or all of the other scenarios disclosed.

[0067] Scenario 1. A gasket for use with a fuel cell stack, the gasket comprising: a compliant layer; a structural layer fixedly attached to the compliant layer; and an adhesive layer comprising an adhesive disposed between the compliant layer and the structural layer and configured to secure the structural layer to the compliant layer, wherein the gasket is impermeable to hydrogen.

[0068] Scenario 2. The gasket of scenario 1, wherein the compliant layer includes an undeformed configuration defining a first thickness and a deformed configuration defining a second thickness smaller than the first thickness, and wherein the compliant layer is movable between the undeformed and the deformed configurations.

[0069] Scenario 3. The gasket of scenario 2, wherein the structural layer has a predetermined thickness, the predetermined thickness being the same for when the compliant layer is in the undeformed state and for when the compliant layer is in the deformed state.

[0070] Scenario 4. The gasket of any of scenarios 1 to 3, further comprising an interface configured to contact a fuel cell in the fuel cell stack and to form a seal between the fuel cell and the gasket.

[0071] Scenario 5. The gasket of any of scenarios 1 to 4 wherein the compliant layer is a closed-cell foam. -1 -

[0072] Scenario 6. The gasket of any of scenarios 1 to 5, wherein the compliant layer includes ethylene propylene diene terpolymer (EPDM).

[0073] Scenario 7. The gasket of any of scenarios 1 to 6, wherein the compliant layer includes polyolefin.

[0074] Scenario 8. The gasket of any of scenarios 1 to 7, wherein the structural layer is an elastomeric rubber.

[0075] Scenario 9. The gasket of any of scenarios 1 to 8, wherein the structural layer includes ethylene propylene diene terpolymer (EPDM).

[0076] Scenario 10. The gasket of any of scenarios 1 to 9, wherein the structural layer includes a fluoropolymer elastomer.

[0077] Scenario 11. The gasket of any of scenarios 1 to 10, wherein the compliant layer is a first compliant layer, the structural layer is a first structural layer, the adhesive layer is a first adhesive layer, and the gasket further comprises: a second compliant layer fixedly attached to the first structural layer; a second structural layer fixedly attached to the second compliant layer; a second adhesive layer disposed between the first structural layer and the second compliant layer; and a third adhesive layer disposed between the second compliant layer and the second structural layer.

[0078] Scenario 12. The gasket of scenario 11, further comprising a fourth adhesive layer disposed on the gasket and configured to contact the fuel cell stack.

[0079] Scenario 13. The gasket of any of scenarios I to 12, further comprising an opening extending thcrethrough and configured to receive a component of the fuel cell stack.

[0080] Scenario 14. The gasket of any of the preceding scenarios, wherein the interface configured to contact the fuel cell includes the compliant layer and the structural layer, and the interface is contoured to complement the fuel cell.

[0081] Scenario 15. The gasket of any of the preceding scenarios, wherein the gasket has a compressed state defining a first height and an uncompressed state defining a second height greater than the first height.

[0082] Scenario 16. The gasket of scenario 15, wherein when the interface of the gasket contacts the fuel cell, the gasket is in the compressed state.

-17 - [0083] Scenario 17. The gasket. of any of the preceding scenarios, wherein the structural layer is between 0.5 mm -2 mm in thickness.

[0084] Scenario 18. The gasket of any of the preceding scenarios, wherein the structural layer is between 0.75 mm -1.5 mm in thickness.

[0085] Scenario 19. The gasket of any of the preceding scenarios, wherein the structural layer is between 0.9 -1.3mm in thickness.

[0086] Scenario 20. The gasket of any of the preceding scenarios, wherein the structural layer is between 1.0 -1.2 mm in thickness.

[0087] Scenario 21. The gasket. of any of the preceding scenarios, wherein the thickness of the structural layer is 72% of the compressed height of the gasket.

[0088] Scenario 22. The gasket of any of the preceding scenarios, whcrcin the adhesive layer is 50 pm.

[0089] Scenario 23. The gasket. of any of the preceding scenarios, wherein the compressed height of the gasket is between 1.4 mm -1.6mm.

[0090] Scenario 24. The gasket of any of the preceding scenarios, wherein the compressed height of the gasket is 1.52 mm.

[0091] Scenario 25. The gasket of any of the preceding scenarios, wherein the uncompressed height of the gasket is between 0.5 rum -5 mm.

[0092] Scenario 26. The gasket of any of the preceding scenarios, wherein the uncompressed height of the gasket is between 1 mm -4 mm.

[0093] Scenario 27. The gasket. of any of the preceding scenarios, wherein the uncompressed height of the gasket is between 2 mm -3 mm.

[0094] Scenario 28. The gasket of any of the preceding scenarios, whcrcin the uncompressed height of the gasket is 2.5 mm.

[0095] Scenario 29. The gasket. of any of the preceding scenarios, wherein the gasket is configured to he placed between a first fuel cell plate and a second fuel cell plate.

[0096] Scenario 30. The gasket of any of the preceding scenarios, wherein the gasket is configured to he placed between a fuel cell plate and a housing of the fuel cell stack.

[0097] Scenario 31. The gasket of any of the preceding scenarios, the gasket having a first end and a second end opposite the first end and a passage extending through the gasket between the first and second ends, wherein the passage is configured to engage with a -18_ channel of a fuel cell plate, and the passage being configured to receive and pass therethrough a fluid to the channel of the fuel cell plate.

[0098] Scenario 32. A method of affixing a gasket within a fuel cell stack, the method comprising: providing a gasket according to any of the preceding scenarios, the gasket being in the uncompressed state; contacting a first fuel cell with the gasket, such that a seal is formed between the first fuel cell and the gasket; and affixing the gasket to a first fuel cell via one or more of the adhesive layers. [0099] Scenario 33. The method of scenario 32, further comprising the steps of: contacting a second fuel cell with the gasket, such that a seal is created between the second fuel cell and the gasket; and compressing the gasket such that the gasket moves from the uncompressed state to the compressed state, wherein the gasket is disposed between the first fuel cell and the second fuel cell.

[0100] Scenario 34 A method of installing a gasket into a fuel cell stack, the method comprising: providing a fuel cell stack having at least two sealing surfaces opposite each other that define a gap between; providing a gasket according to any of scenarios 1 to 31, the gasket being in the first configuration and having a height that is greater than the gap between the two scaling surfaces; applying a compressive force to the gasket in a z,-direction such that the gasket is compressed from the first configuration into the second configuration until the compressed height of the gasket is smaller than the gap; inserting the gasket into the gap such that the gap contacts at least one of the two sealing surfaces; and removing the applied compressive force, such that a second force acts on the gasket from the two sealing surfaces, the second force being a normal force that is reactionary to the pressure applied by the compressed gasket onto each of the two sealing surfaces, -19-wherein moving the gasket from the first configuration to the second configuration includes deforming the compliant layer, and wherein the pressure applied by the compressed gasket is due to the elasticity of the compressed compliant layer.

[0101] Scenario 35. The method of scenario 34, wherein the two sealing surfaces are two fuel cell plates.

[0102] Scenario 36. The method of scenario 34, wherein the two sealing surfaces are a fuel cell plate and a housing of the fuel cell stack.

[0103] Scenario 37. A method of manufacturing a gasket according to any of scenarios 1 to 31 includes the steps of: forming a first structural layer; forming a first compliant layer on top of the first structural layer; and fixedly sealing the first compliant layer to the first structural layer via a first adhesive layer.

[0104] Scenario 38. The method of scenario 37, further comprising a discrete step of applying an adhesive layer to the first structural layer before forming the first compliant layer.

[0105] Scenario 39. The method of scenario 37, further comprising a discrete step of applying an adhesive layer to the first compliant layer.

[0106] Scenario 40. The method of any of scenarios 37 to 39, further comprising the step of forming a second structural layer and affixing the second structural layer via a second adhesive layer to the first compliant layer.

[0107] Scenario 41. The method of any of scenarios 37 to 39, further comprising the step of forming a second structural layer and affixing the second structural layer via a second adhesive layer to the first structural layer.

[0108] Scenario 42. The method of any of scenarios 37 to 41, further comprising forming a second compliant layer and affixing the second compliant layer via a third adhesive layer to the first structural layer.

[0109] Scenario 43. The method of any of scenarios 37 to 41, further comprising forming a second compliant layer and affixing the second compliant layer via a third adhesive layer to the first compliant layer.

-20 - [0110] Scenario 44. The method of any of scenarios 37 to 43, further comprising repeating at least one of the steps.

[0111] Scenario 45. A fuel cell stack comprising: [0112] a housing configured to receive a fuel cell plate; [0H3] a fuel cell plate disposed within the housing, the fuel cell plate defining a channel therein configured to receive a fluid; [0114] a gasket configured to contact the fuel cell plate; [OHS] a fluid inlet disposed on the housing and configured to receive the fluid and pass the fluid to the fuel cell plate channel; and [0116] a fluid outlet disposed on the housing and configured to receive the fluid from the fuel cell plate channel.

[0H7] Scenario 46. The fuel cell stack of scenario 45, wherein the gasket is a gasket according to any one of scenarios 1 to 31.

[0118] Scenario 47. The fuel cell stack of scenario 45 or 46, wherein the fuel cell stack includes a plurality of fuel cell plates disposed in a stacked arrangement, wherein the space between each of the plurality of fuel cell plates defines a predetermined gap configured to receive the gasket therein, the gasket having an uncompressed height that is greater than the gap and the gasket being compressed to a compressed height smaller than the uncompressed height such that the gasket fits into the gap.

[0H9] Scenario 48. The fuel cell stack of any of scenarios 45 to 47, wherein the gasket has a first end defining a first interface and a second end opposite the first end defining the second interface, the gasket further defining a passage extending thercthrough between the first and second ends.

[0120] Scenario 49. The fuel cell stack of scenario 48, wherein one of the first and second interfaces fluidly communicates with the channel of the fuel cell plate, and the other of the first and second interfaces fluidly communicates with the fluid inlet, such that the passage through the gasket is in fluid communication with the fluid inlet and the channel of the fuel cell plate.

[0121] Scenario 50. The fuel cell stack of scenario 48, wherein one of the first and second interfaces fluidly communicates with the channel of one of the plurality of fuel cell plates, and the other of the first and second interfaces fluidly communicates with another of -21 -the plurality of fuel cell plates, such that the passage through the gasket is in fluid communication with the one and the other of the plurality of fuel cell plates.

[0122] Scenario 51. The fuel cell stack of any of scenarios 45 to 50, wherein the fluid is a gas, the fluid inlet is a gas inlet, and the fluid outlet is a gas outlet.

[0123] While the disclosure has been described in connection with the various aspects of the various Figures, it will he appreciated by those skilled in the art that changes could be made to the aspects described above without departing from the broad inventive concept thereof. It is understood, therefore, that this disclosure is not limited to the particular aspects disclosed, and it is intended to cover modifications within the spirit and scope of the present disclosure as defined by the claims.

[0124] Features of the disclosure that are described above in the context of separate aspects may be provided in combination in a single aspect. Conversely, various features of the disclosure that are described in the context of a single aspect may also be provided separately or in any sub-combination. Finally, while an aspect may he described as part of a series of steps or part of a more general structure, each said step may also be considered an independent aspect in itself, combinable with others.

[0125] Recitation of ranges of values herein are merely intended to serve as a shorthand method of referring individually to each separate value falling within the range, unless otherwise indicated herein, and each separate value is incorporated into the specification as if it were individually recited herein. All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context.

[0126] When a list is presented, unless stated otherwise, it is to be understood that each individual element of that list, and every combination of that list, is a separate embodiment. For example, a list of embodiments presented as "A, B, or C" is to be interpreted as including the embodiments, "A," "B," "C," "A or B," "A or C," "B or C," or "A, B, or C." -22 -

Claims

Claims 1. A gasket for use with a fuel cell stack, the gasket comprising: a compliant layer; a structural layer fixedly attached to the compliant layer; and an adhesive layer comprising an adhesive disposed between the compliant layer and the structural layer and configured to secure the structural layer to the compliant layer, wherein the gasket is impermeable to hydrogen.
2. The gasket of claim 1, wherein the compliant layer includes an undeformed configuration defining a first thickness and a deformed configuration defining a second thickness smaller than the first thickness, and wherein the compliant layer is movable between the undeformed and the deformed configurations.
3. The gasket of claim 2, wherein the structural layer has a predetermined thickness, the predetermined thickness being the same for when the compliant layer is in the undeformed state and for when the compliant layer is in the deformed state.
4. The gasket of any of claims I to 3, further comprising an interface configured to contact a fuel cell in the fuel cell stack and to form a seal between the fuel cell and the gasket.
5. The gasket of any of claims 1 to 4, wherein the compliant layer includes ethylene propylene diene terpolymer (EPDM).
6. The gasket of any of claims 1 to 5, wherein the compliant layer includes polyolefin.
7. The gasket of any of claims I to 6, wherein the structural layer is an elastomeric rubber.
8. The gasket of any of claims 1 to 7, wherein the compliant layer is a first compliant layer, the structural layer is a first structural layer, the adhesive layer is a first adhesive layer, and the gasket further comprises: a second compliant layer fixedly attached to the first structural layer; -23 -a second structural layer fixedly attached to the second compliant layer; a second adhesive layer disposed between the first structural layer and the second compliant layer; and a third adhesive layer disposed between the second compliant layer and the second structural layer.
9. The gasket of claim 8, further comprising a fourth adhesive layer disposed on the gasket and configured to contact the fuel cell stack.
10. The gasket of any of claims 1 to 9, further comprising an opening extending therethrough and configured to receive a component of the fuel cell stack.
11. The gasket of any of the preceding claims, wherein the interface configured to contact the fuel cell includes the compliant layer and the structural layer, and the interface is contoured to complement the fuel cell.
12. The gasket of any of the preceding claims, wherein the gasket has a compressed state defining a first height and an uncompressed state defining a second height greater than the first height.
13. The gasket of claim 12, wherein when the interface of the gasket contacts the fuel cell, the gasket is in the compressed state.
14. A method of affixing a gasket within a fuel cell stack, the method comprising: providing a gasket according to any of the preceding claims, the gasket being in the uncompressed state; contacting a fu-st fuel cell with the gasket, such that a seal is formed between the first fuel cell and the gasket; and affixing the gasket to a first fuel cell via one or more of the adhesive layers.
15. The method of claim 14, further comprising the steps of: -24 -contacting a second fuel cell with the gasket, such that a seal is created between the second fuel cell and the gasket; and compressing the gasket such that the gasket moves from the uncompressed state to the compressed state, wherein the gasket is disposed between the first fuel cell and the second fuel cell.-25 -