Protected membrane electrode arrangement for a fuel cell

Abstract

A membrane electrode assembly (MEA) for a fuel cell. The MEA may comprise a first gas diffusion electrode layer (GDE layer), a second GDE layer, a bottom seal, and a membrane embedded between the first and second GDE layers. The MEA may further include a protective barrier configured to protect the membrane from external contaminants. The protective barrier may be configured to surround a portion of the membrane between the surrounding portion of the bottom seal and the second GDE layer.

Description

Introduction

[0001] The present disclosure relates to protecting a membrane electrode assembly (MEA) from external contaminants, such as, but not necessarily limited to, protecting an MEA used in a gas diffusion electrode (GDE) fuel cell architecture.

[0002] In a GDE architecture, an unprotected membrane may have an edge, perimeter, or other surface exposed to external contaminants. Exposure may occur between the GDE layers to such an extent that a pathway is created for life-limiting contaminants such as cations to reach and react with the membrane. A concerning reaction resulting from the penetration of Fe 2+-ions into or interacting with the membrane is that it attacks the chemical structure of the membrane and may destroy it over time. Description

[0003] One non-limiting aspect of the present disclosure relates to protecting a membrane from contaminants, for example, with a protected membrane electrode assembly (MEA) having a protective barrier configured to protect the membrane from external contaminants. The protected MEA can be configured for use with a variety of gas diffusion electrode (GDE) architectures, including, but not limited to, those used in a fuel cell to provide electrical energy to a motor for powering a vehicle.

[0004] One non-limiting aspect of the present disclosure relates to a protected membrane electrode assembly (MEA) for a fuel cell. The protected MEA may include an anode gas diffusion electrode layer (GDE layer) having an anode top and an anode bottom, a cathode GDE layer having a cathode top and a cathode bottom, a membrane having a membrane top and a membrane bottom, the membrane bottom being attached to the cathode top, a subgasket having a subgasket top and a subgasket bottom, the subgasket bottom being attached to the membrane top and the subgasket top being attached to the anode bottom, and a protective barrier configured to protect the membrane from external contaminants.The protective barrier may surround a perimeter of the membrane between the subgasket bottom and the cathode top.

[0005] The protected MEA may include a lateral peripheral portion of the cathode GDE layer forming at least a portion of the protective barrier.

[0006] The protected MEA may include the lateral peripheral portion being bent upward relative to an inner portion of the cathode GDE layer such that the lateral peripheral portion presses against the subgasket bottom surface.

[0007] The protected MEA may include the lateral peripheral portion, which may be formed by removing a segment of the membrane after the membrane has been attached to the cathode GDE layer.

[0008] In the protected MEA, the segment can be removed from the membrane using a laser ablation process.

[0009] With the protected MEA, the segment can be removed from the membrane via a punching process.

[0010] The protected MEA may include a lateral peripheral portion of the membrane forming at least a portion of the protective barrier.

[0011] The protected MEA may include the lateral peripheral portion corresponding to an outer band of the membrane separated from an inner portion of the membrane by a channel.

[0012] In the protected MEA, the channel may be free of any material that encompasses the membrane.

[0013] In the protected MEA, the channel can be formed by removing a segment of the membrane after the membrane has been attached to the cathode GDE layer.

[0014] In the protected MEA, the segment can be removed from the membrane using a laser ablation process or a punching process.

[0015] A non-limiting aspect of the present disclosure relates to a method of manufacturing a protected membrane electrode assembly (MEA) for a fuel cell.The method may include providing an anode gas diffusion electrode (GDE) layer having an anode top surface and an anode bottom surface, providing a cathode GDE layer having a cathode top surface and a cathode bottom surface, providing a membrane having a membrane top surface and a membrane bottom surface, providing a subgasket having a subgasket top surface and a subgasket bottom surface, removing a membrane portion of the membrane to provide a protective barrier for protecting the membrane from external contaminants, adhering the anode bottom surface to the subgasket top surface and the membrane top surface, and adhering the subgasket bottom surface to the membrane top surface such that the protective barrier surrounds a perimeter of the membrane between the subgasket bottom surface and the cathode top surface.

[0016] The method may include providing the protective barrier based at least in part on bending a cathode portion of the cathode GDE layer coincident with the membrane portion upwardly relative to an inner portion of the cathode GDE layer such that at least a portion of the cathode portion presses against the underside of the subgasket.

[0017] The method may comprise providing the protective barrier based at least in part on removing the membrane portion such that the membrane is divided into an outer membrane band and an inner membrane portion, the outer membrane band surrounding the inner membrane portion and being offset therefrom by a channel.

[0018] The method may include removing the membrane section after the membrane bottom surface has been bonded to the cathode top surface.

[0019] The method may involve removing the membrane section before bonding the membrane bottom to the cathode top.

[0020] One non-limiting aspect of the present disclosure relates to a protected membrane electrode assembly (MEA) for a fuel cell. The protected MEA may include a first gas diffusion electrode (GDE) layer, a second GDE layer, a subgasket, a membrane disposed between the first and second GDE layers and at least one surrounding subgasket portion of the subgasket, and a protective barrier configured to protect the membrane from external contaminants. The protective barrier may surround a perimeter of the membrane between the surrounding subgasket portion and the second GDE layer.

[0021] The protected MEA may include forming the protective barrier with a curved portion of the second GDE layer.

[0022] The protected MEA may include forming the protective barrier with a channel, wherein the channel is shaped to divide the membrane into an outer membrane band and an inner membrane section.

[0023] The protected MEA may include forming the protective barrier by removing a portion of the membrane.

[0024] These features and advantages, as well as other features and advantages of the present teachings, will be readily apparent from the following detailed description of the embodiments of the present teachings, taken in conjunction with the accompanying drawings. It should be understood that, although the following figures and embodiments may be described separately, individual features thereof may be combined to form additional embodiments. Brief description of the drawings

[0025] The accompanying drawings, which may be incorporated in and constitute a part of this specification, illustrate embodiments of the disclosure and, together with the description, serve to explain the principles of the disclosure. Fig. 1 shows a schematic view of a vehicle according to a non-limiting aspect of the present disclosure. Fig. 2 shows a schematic view of a fuel cell system according to a non-limiting aspect of the present disclosure. Fig. 3 shows an MEA manufacturing system according to a non-limiting aspect of the present disclosure. Fig. 4 shows a cross-sectional view of an assembled MEA according to a non-limiting aspect of the present disclosure. Fig. 5 shows a cross-sectional view of a protected MEA according to a non-limiting aspect of the present disclosure. Fig. 6 shows another MEA manufacturing system according to a non-limiting aspect of the present disclosure. Fig. 7 shows a cross-sectional view of another assembled MEA in accordance with a non-limiting aspect of the present disclosure. Detailed description

[0026] As required, detailed embodiments of the present disclosure may be disclosed herein; however, it is to be understood that the disclosed embodiments are merely exemplary of the disclosure that may be embodied in various and alternative forms. The figures are not necessarily to scale; some features may be exaggerated or reduced to show details of particular components. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a representative basis for showing one skilled in the art how to variously employ the present disclosure.

[0027] Fig. 1 shows a schematic view of a vehicle 10 in accordance with one non-limiting aspect of the present disclosure. The vehicle 10 may be configured with a drive system, powertrain, or other driveline 12 including an electric motor 14 or other electrically powered device used to propel or otherwise propel the vehicle 10. The vehicle 10 may be depicted as a hybrid vehicle for exemplary, non-limiting purposes, as the powertrain 12 optionally includes an internal combustion engine (ICE) 16. The internal combustion engine 16 and the electric motor 14 or other electrical-to-mechanical energy conversion device may cooperate to provide rotational power / torque to one or more wheels 20, 22, 24, 26.The driveline (12) may include a transmission (34), a driveshaft (36), a differential (38), axles (40, 42), and / or other components to facilitate the transmission of rotational power from the ICE 16 and / or the engine (14) to the wheels (20, 22, 24, 26). The vehicle 10 may be illustrated as including the driveline 12 configured to connect the ICE 16 and the engine 14 to the front wheels 20, 24 for non-limiting purposes, as the present disclosure fully contemplates its use and application with four-wheel drive automobiles and other non-automotive vehicle types. A controller 44 may be configured to generate control signals associated with controlling and otherwise implementing the desired control of the powertrain 12, the engine 14, the ICE 16, and / or other features of the vehicle 10.

[0028] The vehicle 10 is representative of a variety of vehicles and / or other devices that may rely on the conversion of electrical energy to mechanical energy. Such vehicles may be generally referred to as electric vehicles and include a wide range of capabilities to support the conversion of electrical energy to mechanical energy. The vehicle 10 may include various configurations for generating, storing, and delivering electrical energy to the electric motor 14 and / or other devices or systems onboard the vehicle 10. One non-limiting aspect of the present disclosure relates to the electrical energy being provided at least in part based on electrical energy derived from a fuel cell system 46.The fuel cell system 46 may be configured to generate electrical energy by relying at least in part on electrochemical reactions of a type suitable for generating electrical energy. Fig. 2 shows a schematic view of the fuel cell system 46 according to one non-limiting aspect of the present disclosure. The system 46 may include one or more fuel cell stacks 48, each of which may be comprised of a plurality of fuel cells 50, e.g., polymer electrolyte membrane (PEM) fuel cells (PEMFCs), that may be stacked and electrically connected in series or parallel to one another. Each fuel cell 50 may be a multi-layer construction having an anode side 54 and a cathode side 56, which may be separated by a proton-conducting membrane 58, which may be referred to herein as membrane 58.

[0029] An anode gas diffusion electrode (GDE) layer 60 may be provided on the anode side 54 of the PEMFC, to which an anode catalyst layer 62 is attached or disposed therebetween to interconnect the membrane 58 and the corresponding GDE layer 60. A cathode GDE layer 64 may be disposed at an opposing distance from the anode layers 60 and 62 and may be provided on the cathode side 56 of the membrane 48. A cathode catalyst layer 66 may be attached to the GDE layer 64 or disposed between the membrane 58 and the corresponding GDE layer 64, operatively connecting them. The two GDE layers 60 and 64, the two catalyst layers 56 and 66, and the subgaskets 68, together with the membrane 58, form, in whole or in part, a membrane electrode assembly (MEA) 70.The GDE layers 60 and 64 may be porous structures that provide fluid inlet into and outlet from the MEA 70. An anode flow field plate 72 (with optional bipolar plate) may be provided on the anode side 54 in abutting relationship with the anode GDE layer 60. A cathode flow field plate 74 (with optional bipolar plate (BPP)) may be provided on the cathode side 56 in abutting relationship with the cathode GDE layer 64.

[0030] Coolant flow channels may be configured to traverse each of the plates 72 and 74 to allow coolant to flow through the fuel cell 50. Liquid inlet ports and headers may direct a hydrogen-rich fuel and an oxidizer to the respective passages in the anode and cathode flow-field plates 72, 74. A central active region of the anode flow-field plate 72, facing the proton-conducting membrane 58, may be provided with an anode flow field consisting of serpentine flow channels for distributing hydrogen across an opposing surface of the GDE layer 60 and the membrane 58. The MEA 70 and the flow-field plates 72, 74 may be stacked together between current collector plates and monopolar end plates (not shown).The fuel cell system 46 may also utilize anode recirculation, in which an anode recirculation gas is supplied from an exhaust manifold or header through an anode recirculation line to recycle hydrogen back to the anode side inlet 54, thus conserving hydrogen gas in the stack 48. The hydrogen (H2) inlet stream—whether gaseous, concentrated, entrained, or otherwise—may be directed from a hydrogen source, e.g., a fuel storage tank 46, to the anode side 54 of the fuel cell stack 48 via a fluid injector 47 connected to a (first) fluid inlet line or hose.

[0031] The fuel cell stack 48 may be of the type commonly used in automotive applications, such as, but not necessarily limited to, a fuel cell stack 48 that may utilize a solid polymer electrolyte membrane (PEM)—also referred to as a proton exchange membrane (PEM)—to facilitate the electrolysis process by providing ion transport between an anode and a cathode. In proton exchange membrane fuel cells (PEMFCs), a proton-conducting solid polymer electrolyte (SPE) membrane may be used, such as a perfluorosulfonic acid membrane. The anode and cathode (not shown in detail) of the fuel cell stack 48 may contain dispersed catalytic particles, such asPlatinum, deposited on carbon particles and mixed with an ionomer. This catalyst mixture can be deposited on the sides of the membrane to form anode and cathode layers. The combination of the anode catalytic layer, the cathode catalytic layer, and the electrolyte membrane can form the MEA 58, in which the anode catalyst and the cathode catalyst can be deposited on opposite sides of the ion-conducting solid polymer membrane. To prevent Fe. 2+ -ions and / or other external contaminants penetrate or interact with the membrane, so that over time they attack and possibly destroy the chemical structure of the membrane, one aspect of the present disclosure provides that the MEA is protected.

[0032] Fig. 3 schematically illustrates an MEA manufacturing system 84 in accordance with one non-limiting aspect of the present disclosure. The MEA manufacturing system 84 may be configured to manufacture an MEA 86 with a protective barrier 88. The protective barrier 88 may be used to protect the MEA 86, where the protective barrier 88 may serve to prevent, minimize, thwart, or otherwise limit the exposure of a membrane 90 to external contaminants. For example, the protective barrier 88 may be used in the manner described to limit the likelihood or possibility of Fe 2+Ions and / or other external contaminants may penetrate or interact with the membrane 90, acting against the chemical structure of the membrane 90 and potentially destroying it over time. The protected MEA 86 may be configured for use with a variety of GDE and non-GDE architectures, including, but not limited to, those used in other devices, vehicles, etc., so the present disclosure fully contemplates the protected MEA 86 operating in other environments in addition to the fuel cell 48 and / or fuel cell system 46 described above. The protected MEA 86 is described with respect to the fuel cell system 46 to demonstrate the advantageous capabilities of the protected MEA 86 to protect the membrane 90 from external contaminants that may be particularly prevalent in an operating environment of the vehicle 10.

[0033] The MEA manufacturing system 84 may include an anode coil 92 having a supply of material suitable for forming an anode GDE layer 94. The anode GDE layer 94 may be created, in part, by cutting, separating, extracting, or otherwise obtaining the anode GDE layer 94 from the anode coil 92. This is illustrated, for non-limiting purposes, with respect to an embossing, laser, or stamping tool or operation 96 that serves to cut the anode GDE layer 94 into a desired shape and configuration once it has been unwound from the anode coil 92. Alternatively, the anode GDE layer 94 may be provided by other mechanisms and / or as a pre-cut component having the desired shape, size, configuration, etc.The proprietary MEA 86 manufacturing system may include a cathode coil 100 having a supply of material suitable for forming a cathode GDE layer 102, which, as shown, includes a membrane 90 integrated therewith, i.e., included as part of the material supplied with the cathode coil 100. The cathode GDE layer 102 and the membrane 90 may be created, in part, by cutting, separating, extracting, or reclaiming the cathode GDE layer 102 from the cathode coil 100. This is illustrated for non-purposes with respect to an embossing, laser, or punching tool or operation 104 capable of cutting the cathode GDE layer 102 and the membrane 90 together into a desired shape and configuration once unwound from the cathode coil 100.Alternatively, the cathode GDE layer 102 may be provided by other mechanisms, the membrane layer 90 may be spooled or supplied separately, and / or the cathode layer and / or the membrane 90 may be received as pre-cut component(s) having the desired shape, size, configuration, etc.

[0034] Once the anode GDE layer 94, the cathode GDE layer 102, and the membrane 90 are cut, the MEA manufacturing system 84 may include a protective barrier tool 106 that may be used to perform a barrier protection process, thereby adding a portion of the protective barrier 88. In the illustrated configuration, the protective barrier 88 may be added by removing a membrane portion 108 of the membrane 90; that is, the protective barrier 88 may conform to a portion 110 of the cathode GDE layer 102 that coincides with the membrane portion 108 removed from the membrane 90. For example, the protective barrier tool 106 may be configured to support a laser ablation process, a punching process, or other removal process suitable for removing the membrane portion 108 from the membrane 90 adhered to the cathode GDE layer 102.The membrane portion 108 removed from the membrane 90 may result in the membrane 90 having a smaller footprint than before the removal process. The MEA manufacturing system 84 may include an assembly process 112 for assembling the cathode GDE layer 102, the membrane 90, a subgasket 114, and the anode GDE layer 94. The subgasket 114 may be used for sealing and other protection for the membrane 90 and may be provided from a spool (not shown) or other mechanism, such as a cut piece. A resulting assembled MEA 116 may be provided following the assembly process 112.

[0035] Fig. 4 schematically illustrates a cross-sectional view of the assembled MEA 116 according to one non-limiting aspect of the present disclosure. The assembled MEA 116 may include the cathode GDE layer 102, the membrane 90, the subgasket 114, and the anode GDE layer 94. The cathode GDE layer 102 may include a cathode catalyst layer 118, and the anode GDE layer 94 may include an anode catalyst layer 120. The subgasket 114 may consist of upper and lower sections 124, 126 held together by a bonding or other adhesive element 128. This exemplary representation of the assembled MEA 116 is not limiting, as the present disclosure fully contemplates the assembled MEA 116 with additional layers, components, etc., including fewer layers, components, etc.The anode GDE layer 94 may include an anode top surface 132 and an anode bottom surface 134, the cathode GDE layer 102 may include a cathode top surface 136 and a cathode bottom surface 138, the membrane 90 may include a membrane top surface 142 and a membrane bottom surface 144, with the bottom surface of the membrane 90 being attached to the cathode top surface 136, and the subgasket 114 may include a subgasket top surface 146 and a subgasket bottom surface 148, with the subgasket bottom surface 148 being attached to the membrane top surface 142 and the subgasket top surface 146 being attached to the anode bottom surface 134. A separation 150 between the subgasket 114 and the cathode GDE layer 102 may result in a window forming between the membrane 90 and an external environment.

[0036] The cathode GDE layer 102 may include a lateral perimeter portion 152 proximate the window that protrudes or extends beyond a perimeter 154 of the membrane 90. The lateral perimeter portion 152 may surround the entire perimeter 154 of the membrane 90 between the subgasket bottom 148 and the cathode top 136. One non-limiting aspect of the present disclosure contemplates the use of the lateral perimeter portion 152 to provide the protective barrier 88 for the membrane 90. Back to Fig. 3, the protective barrier 88 may be provided by bending the lateral peripheral portion 152 upward relative to an inner portion 156 of the cathode GDE layer 102 such that the lateral peripheral portion 152 presses against the subgasket bottom 148. A bending process 162 of the MEA manufacturing system 84 may include a tool or other method for bending the cathode GDE layer 102 in the manner contemplated to provide the protected MEA 86. The bending process 162 may include coining, pressing, or otherwise physically forcing the lateral peripheral portion 152 to press against and optionally seal with the subgasket 114. The bending process 162 may optionally include heating elements or other processes, e.g., B. etching, etc., to facilitate bending of the cathode GDE layer 102, and / or the use of adhesives, sealants, etc.to further ensure a tight seal between the subgasket 114 and the cathode GDE layer 102.

[0037] Fig. 5 schematically shows a cross-sectional view of the protected MEA 86 in accordance with a non-limiting aspect of the present disclosure. The bending operation 162 may be advantageous to press the lateral peripheral portion 152 of the GDE layer 102 against the subgasket 114, which may result in a slight gap 164 forming between an edge of the membrane 90 and a sealing interface 164 between the subgasket 114 and the cathode GDE layer 102. The protective barrier 88 may be used in this manner to prevent external contaminants from passing through the Fig. 4. The removal of the membrane section 108 and the bending of the cathode GDE layer 102 may result in the membrane 90 and the cathode GDE layer 102 having a slightly shorter or narrower profile relative to the removal and bending processes. This narrowing may be compensated for by shaping the membrane 90 and / or the cathode GDE layer 102 accordingly larger or wider in anticipation of the narrowing. The resulting protective barrier 88 may serve to prevent the penetration of Fe 2+-ions and / or other external contaminants into or interacting with the membrane 90 in a manner that counteracts the chemical structure of the membrane 90 and potentially destroys it over time. The ability to provide the protective barrier 88, optionally using the cathode GDE layer 102 and a minor removal of a portion of the segment 110 of the membrane 90, may be advantageous for protecting the membrane 90 from external contaminants without requiring the addition of additional components, devices, etc., beyond what is already included as part of the MEA.

[0038] Fig. 6 schematically illustrates another MEA manufacturing system 170 according to a non-limiting aspect of the present disclosure. The MEA manufacturing system 170 may be configured to manufacture an MEA 172 with a different type of protective barrier 174. The MEA manufacturing system 170 may include the anode coil 92, the cathode coil 100, the forming tools 96, 104, and the related processes described above. Once the anode GDE layer 94, the cathode GDE layer 102, and the membrane 90 are cut, the MEA manufacturing system 170 may include a protective barrier tool 178 that may be used to perform a barrier protection process, thereby adding the protective barrier 174. In the illustrated configuration, the protective barrier 174 may be added by removing a membrane portion 180 of the membrane 90, i.e.The protective barrier 174 may conform to a portion of the cathode GDE layer 102 that coincides with the membrane portion 180 removed from the membrane 90. For example, the protective barrier tool 178 may be configured to support a laser ablation process, a punching process, or other removal process suitable for removing the membrane portion 180 from the membrane 90 adhered to the cathode GDE layer 102. Removing the membrane portion 180 may result in the membrane 90 being split into an outer membrane band 182 and an inner membrane portion 184, with the outer membrane band 182 surrounding the inner membrane portion 184 and separated therefrom by a channel 186. The MEA manufacturing system 170 may include the assembly process 112 for assembling the cathode GDE layer 102, the membrane 90, a subgasket 114, and the anode GDE layer 94.

[0039] Fig.Figure 7 schematically illustrates a cross-sectional view of the protected MEA 172 according to one non-limiting aspect of the present disclosure. The MEA 172 may include the cathode GDE layer 102, the membrane 90, the subgasket 114, and the anode GDE layer 94. The use of the protective barrier 174 to provide the channel 186 between the outer membrane band 182 and the inner membrane portion 184 may result in the outer membrane band 182 acting as a sacrificial component. The outer membrane band 182 may thus be used to create a barrier 174 for chemical reagents that can interact with external contaminants to prevent these contaminants from effectively reaching the inner membrane portion 184. The size, shape and width of the outer membrane band 182 and / or the channel 186 may be a design parameter that varies depending on the material properties of the respective components.While the present disclosure certainly contemplates the inclusion of additional sealants or materials to cooperate with the protective barrier 174, the ability to provide the protective barrier 174 without the use of such additional features may be advantageous to prevent external contaminants from reaching the membrane 90 without requiring the addition of additional components, devices, etc., beyond what is already included as part of the MEA 172. While the protective barrier 174 is described in terms of being formed within the membrane 90 using a laser or a stamping process, the present disclosure also contemplates other mechanisms for creating the outer membrane band 90, such as melting or deactivating the edge of the membrane 90 instead of completely ablating it.

[0040] As stated above, the present disclosure relates to fabricating MEAs using lasers, such as femtosecond and nanosecond pulsed lasers or the like, which may involve cutting the membrane layer without damaging the underlying GDE and then cutting the remaining GDE at a location such that the cut edge of the GDE layer extends beyond the cut edge of the membrane layer. The resulting layered structure combination of membrane and GDE may be further combined and laminated with a second GDE to form an MEA, the resulting MEA having better resistance to chemical degradation of the membrane layer. The MEA may be constructed such that the outer edge of the membrane is protected by the GDE.Using laser technology to selectively ablate the surface of the GDE and the membrane at specific locations and depths can enable the construction of layers with different dimensions without the need for additive assembly techniques or complex cutting processes. In one aspect, selective surface ablation can be performed at the edge of the GDE with the membrane to eliminate the path for contaminants; for example, laser ablations can be performed to a depth of approximately 20 µm and a desired width. In another aspect, the membrane can be removed by laser ablation below the subgasket and a few micrometers from the edge to form a trough-like design.The present disclosure may enable the large-scale production of MEAs with design features aimed at extending MEA durability, particularly membrane lifetime, by limiting the path for life-limiting contaminants reaching the membrane. The use of laser methods may reduce the cycle time required to cut the part and incorporate the design features needed to extend MEA lifetime. This design and method may also enable the large-scale production of laminated membranes from roll to roll and advanced coated membranes on electrodes. The present disclosure may enable process plants to use more service-friendly solutions that do not incur significant maintenance costs, such as the replacement or longevity of a cutting process, e.g.,A laser cutting process can achieve much higher precision and quality of the manufactured parts over time because less tool wear occurs.

[0041] The terms "consisting of," "including," and "having" are all-inclusive and therefore specify the presence of certain features, steps, operations, elements, or components, but do not preclude the presence or addition of one or more other features, steps, operations, elements, or components. The order of steps, processes, and operations may be changed where possible, and additional or alternative steps may be used. The term "or" as used in this description includes all combinations of the listed elements. The term "each of" includes every possible combination of the listed items, including "each of" the listed items. "A," "a," "the," "at least one," and "one or more" are used interchangeably to indicate that at least one of the items is present.There may be more than one of these elements unless the context clearly indicates otherwise. All values ​​of parameters (e.g., quantities or conditions), unless expressly stated otherwise or in light of the context, including the appended claims, are to be understood as being modified in all cases by the term "via," regardless of whether "via" actually appears before the value or not. A component "configured" to perform a particular function is capable of performing the specified function without modification, rather than merely having the potential to perform the specified function after further modifications. In other words, if the described hardware is expressly configured to perform the specified function, then it is specifically selected, created, implemented, used, programmed, and / or designed to perform the specified function.

[0042] While various embodiments have been described, the description is intended to be exemplary and not restrictive, and it will be apparent to those skilled in the art that many other embodiments and implementations are possible that fall within the scope of the embodiments. Any feature of one embodiment may be used in combination with, or in place of, another feature or element in another embodiment, unless expressly limited. Accordingly, the embodiments are not to be limited except in accordance with the appended claims and their equivalents. Also, various modifications and changes may be made within the scope of the appended claims.Although several modes for carrying out the many aspects of the present teachings have been described in detail, those familiar with the art to which these teachings relate will recognize various alternative aspects for carrying out the present teachings that fall within the scope of the appended claims. It is intended that everything contained in the above description or shown in the accompanying drawings be considered illustrative and exemplary of the entire range of alternative embodiments that one of ordinary skill in the art would recognize as being implied, structurally and / or functionally equivalent, or otherwise obvious based on the content included, and not as limited solely to the embodiments expressly shown and / or described.

Claims

[1] A protected membrane electrode assembly (MEA) for a fuel cell, comprising: an anode gas diffusion electrode (GDE) layer having an anode top side and an anode bottom side; a cathode GDE layer having a cathode top side and a cathode bottom side; a membrane having a membrane top side and a membrane bottom side, the membrane bottom side being attached to the cathode top side; a subgasket having a subgasket top and a subgasket bottom, the subgasket bottom being attached to the membrane top and the subgasket top being attached to the anode bottom; and a protective barrier configured to protect the membrane from external contaminants, the protective barrier surrounding a perimeter of the membrane between the subgasket bottom and the cathode top. [2] Protected MEA according to claim 1, wherein: a lateral peripheral portion of the cathode GDE layer forms at least a portion of the protective barrier. [3] Protected MEA according to claim 2, wherein: the lateral peripheral portion is bent upward relative to an inner portion of the cathode GDE layer so that the lateral peripheral portion presses against the subgasket bottom. [4] Protected MEA according to claim 3, wherein: the lateral peripheral portion is formed by removing a segment of the membrane after the membrane has been attached to the cathode GDE layer. [5] Protected MEA according to claim 4, wherein: the segment is removed from the membrane using a laser ablation process. [6] Protected MEA according to claim 4, wherein: the segment is removed from the membrane via a punching process. [7] Protected MEA according to claim 1, wherein: a lateral peripheral portion of the membrane forms at least a portion of the protective barrier. [8] Protected MEA according to claim 7, wherein: the lateral peripheral portion corresponds to an outer band of the membrane which is offset by a channel from an inner portion of the membrane. [9] Protected MEA according to claim 8, wherein: the channel is free of any material that encompasses the membrane. [10] Protected MEA according to claim 8, wherein: the channel is formed by removing a segment of the membrane after the membrane has been attached to the cathode GDE layer.

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