Ion scavengers in fuel cell electrodes

Abstract

The present invention relates to ion scavengers in fuel cell electrodes. A fuel cell comprises an anode including an anode side, an anode-side gas diffusion layer, and an anode-side bipolar plate formed of a first metal material, and a cathode side including a cathode, a cathode-side gas diffusion layer, and a cathode-side bipolar plate formed of a second metal material. The fuel cell also includes a membrane having a first side and a second side positioned between the anode side and the cathode side. The fuel cell also includes an embedding body positioned in the anode side and / or the cathode side. The embedding body is configured to embed metal ions formed of the first and / or second metal materials.

Description

Technical Field

[0001] The present disclosure relates to ion scavengers in fuel cell electrodes. The ion scavengers can be configured to remove ions (eg, metal ions) generated by bipolar plate corrosion to mitigate fuel cell membrane and ionomer degradation. Background Art

[0002] Bipolar plates (BPPs) are important components of fuel cells, including proton exchange membrane fuel cells (PEMFCs). The bipolar plates are configured to evenly distribute fuel (H2) and oxidant (air) to the anode and cathode sides of the fuel cell stack, respectively. The BPPs can also be configured as current collectors, provide mechanical support for the fuel cell, and promote water and heat transfer in the fuel cell. BPPs are typically formed of metal materials because they have superior thermal and electrical conductivity, mechanical strength, impermeability, ease of manufacturing, and / or relatively low cost compared to graphite or carbon-polymer composite BPPs. The metal material can be an alloy. The alloy can be an austenitic steel, such as 316 stainless steel (e.g., SS316L or SS316). Summary of the Invention

[0003] According to one embodiment, a fuel cell is disclosed. The fuel cell includes an anode side, which includes an anode, an anode-side gas diffusion layer, and an anode-side bipolar plate formed of a first metal material. The fuel cell also includes a cathode side, which includes a cathode, a cathode-side gas diffusion layer, and a cathode-side bipolar plate formed of a second metal material. The fuel cell also includes a membrane having a first side and a second side positioned between the anode side and the cathode side. The anode is positioned between the anode-side gas diffusion layer and the membrane. The cathode is positioned between the cathode-side gas diffusion layer and the membrane. The anode-side bipolar plate is positioned adjacent to the anode-side gas diffusion layer and opposite to the membrane. The cathode-side bipolar plate is positioned adjacent to the cathode-side gas diffusion layer and opposite to the membrane. The fuel cell also includes an embedded body located in the anode side and / or cathode side. The embedded body is configured to embed metal ions formed of the first and / or second metal material.

[0004] According to one embodiment, a fuel cell is disclosed. The fuel cell includes an anode side, which includes an anode, an anode-side gas diffusion layer, and an anode-side bipolar plate formed of a first metal material. The fuel cell also includes a cathode side, which includes a cathode, a cathode-side gas diffusion layer, and a cathode-side bipolar plate formed of a second metal material. The fuel cell also includes a membrane having a first side and a second side positioned between the anode side and the cathode side. The anode is positioned between the anode-side gas diffusion layer and the membrane. The cathode is positioned between the cathode-side gas diffusion layer and the membrane. The anode-side bipolar plate is positioned adjacent to the anode-side gas diffusion layer and opposite to the membrane. The cathode-side bipolar plate is positioned adjacent to the cathode-side gas diffusion layer and opposite to the membrane. The fuel cell also includes an embedding body configured to embed metal ions formed of the first and / or second metal materials.

[0005] According to one embodiment, a fuel cell is disclosed. The fuel cell includes an anode side, which includes an anode, an anode-side gas diffusion layer, and an anode-side bipolar plate formed of a first metal material. The fuel cell also includes a cathode side, which includes a cathode, a cathode-side gas diffusion layer, and a cathode-side bipolar plate formed of a second metal material. The fuel cell also includes a membrane having a first side and a second side positioned between the anode side and the cathode side. The anode is positioned between the anode-side gas diffusion layer and the membrane. The cathode is positioned between the cathode-side gas diffusion layer and the membrane. The anode-side bipolar plate is positioned adjacent to the anode-side gas diffusion layer and opposite to the membrane. The cathode-side bipolar plate is positioned adjacent to the cathode-side gas diffusion layer and opposite to the membrane. The fuel cell also includes a metal ion scavenger, which is coated between the anode-cathode gas diffusion layer and / or the cathode gas diffusion layer and the anode bipolar plate and / or the cathode bipolar plate, respectively, and on the anode-cathode gas diffusion layer and / or the cathode gas diffusion layer to form a metal ion scavenging layer. The metal ion scavenger is configured to scavenge metal ions formed of the first and / or second metal materials. BRIEF DESCRIPTION OF THE DRAWINGS

[0006] Figure 1 A schematic side view of a fuel cell is depicted.

[0007] Figure 2 Depicts Figure 1 Schematic exploded side view of a portion of the anode side of a fuel cell is shown in FIG.

[0008] Figure 3 A schematic exploded side view of a known implementation of CeO2 within a fuel cell is depicted.

[0009] Figure 4 Depicted is a schematic exploded side view of an ion scavenger incorporated into a fuel cell component (eg, an anode) according to one embodiment. DETAILED DESCRIPTION

[0010] Embodiments of the present disclosure are described herein. However, it should be understood that the disclosed embodiments are merely examples and that other embodiments may take various and alternative forms. The drawings are not necessarily to scale; some features may be enlarged or minimized to show details of particular components. Therefore, the specific structural and functional details disclosed herein should not be construed as limiting, but merely as a representative basis for teaching those skilled in the art to adopt the embodiments in a variety of ways. As those of ordinary skill in the art will understand, the various features illustrated and described with reference to any of the accompanying drawings may be combined with features illustrated in one or more other drawings to produce embodiments that are not explicitly illustrated or described. The combinations of illustrated features provide representative embodiments of typical applications. However, various combinations and variations of features consistent with the teachings of the present disclosure may be desirable for particular applications or implementations.

[0011] Except where expressly indicated in the Examples or otherwise, all numerical quantities in this specification indicating amounts of materials or conditions of reaction and / or use should be understood as modified by the word "about" in the broadest sense of the invention. Practice within the numerical limits stated is generally preferred. Likewise, unless expressly stated to the contrary: percentages, "parts," and ratios are by weight; the term "polymer" includes "oligomers," "copolymers," "terpolymers," and the like; a description of a group or class of materials as suitable or preferred for a given purpose in connection with the present invention indicates that mixtures of any two or more members of that group or class are also suitable or preferred; the molecular weight provided for any polymer refers to the number-average molecular weight; descriptions of ingredients in chemical terms refer to the ingredients when added to any combination specified in the description and do not necessarily exclude chemical interactions between the ingredients of the mixture once mixed; the first definition of an acronym or other abbreviation applies to all subsequent uses of the same abbreviation herein and applies mutatis mutandis to conventional grammatical variations of the initially defined abbreviation; and, unless expressly stated to the contrary, measurements of properties are determined by the same techniques as previously or subsequently cited for the same property.

[0012] The present invention is not limited to the specific embodiments and methods described below, as specific components and / or conditions may of course vary. Furthermore, the terminology used herein is used only for the purpose of describing embodiments of the present invention and is not intended to be limiting in any way.

[0013] As used in the specification and the appended claims, the singular forms "a," "an," and "the" include plural referents unless the context clearly dictates otherwise. For example, a component mentioned in the singular is intended to include a plurality of components.

[0014] The term "substantially" may be used herein to describe embodiments disclosed or claimed. The term "substantially" may modify a value or relative property disclosed or claimed in this disclosure. In this context, "substantially" may mean that the value or relative property it modifies is within ±0%, 0.1%, 0.5%, 1%, 2%, 3%, 4%, 5%, or 10% of that value or relative property.

[0015] Bipolar plates (BPPs) are important components of fuel cells, including proton exchange membrane fuel cells (PEMFCs). The bipolar plates are configured to evenly distribute fuel (H2) and oxidant (air) to the anode and cathode sides of the fuel cell stack, respectively. The BPPs can also be configured as current collectors, provide mechanical support for the fuel cell, and promote water and heat transfer in the fuel cell. BPPs are typically formed of metal materials because they have superior thermal and electrical conductivity, mechanical strength, impermeability, ease of manufacturing, and / or relatively low cost compared to graphite or carbon-polymer composite BPPs. The metal material can be an alloy. The alloy can be an austenitic steel, such as 316 stainless steel (e.g., SS316L or SS316).

[0016] Despite one or more of the benefits identified above, metal BPPs may also have one or more disadvantages. Metal BPPs may suffer from poor corrosion resistance in the cyclical oxidizing and reducing environment of a PEMFC. Corrosion of the BPP may result in leaching of metal ions from the BPP into the membrane electrode assembly (MEA), which includes the membrane (e.g., polymer electrolyte membrane), anode, cathode, and first and second gas diffusion layers (GDLs). The leached metal ions may include chromium (Cr), iron (Fe), nickel (Ni), and / or other metal ions formed from metals present in the BPP alloy.

[0017] The anode side BPP may be more susceptible to leaching than the cathode side BPP, thereby providing a source of leached metal ion contaminants into the membrane and anode catalyst layer. Metal ion contamination can significantly reduce fuel cell performance by increasing the membrane resistance and interfacial resistance between the BPP and the membrane. For example, Fe ions can promote degradation of membrane materials, such as Nafion ionomers available from DuPont Company. Leaching primarily results in Fe 3+ The ions are fixed to the sulfonic groups of the membrane material, forming toxic membrane sites. In the presence of H₂O₂, these sites generate hydroxyl radicals, which are highly reactive species. The most reactive hydroxyl radicals can degrade the polymer chains of the membrane material. This degradation can lead to the loss of fluoride from the polymer chains, thus forming pinholes in the membrane.

[0018] A known method to mitigate membrane degradation is to provide CeO2 in the membrane and / or catalyst layer. 3+ Ions in the catalytic cycle ● OH radicals react to scavenge harmful free radicals. This known method may have one or more disadvantages. CeO2-containing membranes are relatively expensive. In addition, these membranes generally exhibit low proton conductivity and over time the membranes may lose their free radical scavenging ability because CeO2 3+ The ions are flushed away by the humidified gas flow.

[0019] In one or more embodiments, a novel method for ion scavenging in PEMFCs to mitigate membrane degradation is disclosed. The novel method may include incorporating a scavenger into the catalyst layer on the anode side. The scavenger may be one or more cation-intercalating host materials and / or one or more chelating ligands. The scavenger may be configured to remove ions generated by corrosion of the BPP to mitigate fuel cell membrane and ionomer degradation. The BPP may be formed from the same or different metal materials.

[0020] Figure 1 A schematic side view of a fuel cell 10 is depicted. The fuel cells 10 can be stacked to form a fuel cell stack. The fuel cell 10 includes an anode side 12 and a cathode side 14. The anode side 12 includes a bipolar plate (BPP) 16 that is configured to distribute H2 to the anode side 12 as indicated by arrows 18. The cathode side 14 includes a BPP 20 that is configured to distribute air to the cathode side 14 as indicated by arrows 22. The anode side 12 also includes a gas diffusion layer (GDL) 24 and an anode 26. The cathode side 14 includes a GDL 28 and a cathode 30. A membrane 32 is located between the anode side 12 and the cathode side 14.

[0021] The hydrogen oxidation reaction (HOR) occurs on the anode side 12 of the fuel cell 10. The HOR oxidizes H2 to generate electrons (e - ) and protons (H + ), as shown in the following reaction equation:

[0022]

[0023] The oxygen reduction reaction (ORR) occurs on the cathode side 14 of the fuel cell 10. The ORR reduces oxygen from the air distributed by the BPP 20 and reacts with the H generated by the HOR. + The reaction forms water, as shown in the following reaction equation:

[0024]

[0025] In the acidic environment that may be present on the anode side 12, the BPP 16 may undergo corrosion reactions and release metal ions, such as Fe 3+ ions. According to Fe 3+ Example of ion, Fe 3+ The ions can bind to the membrane material in the fuel cell membrane 32, such as Nafion ionomer, and act as a catalyst for the production of H2O2. ● The H 2 O 2 is a catalytic site for OH radicals, which are a byproduct of ORR at the cathode 30 . ● OH radicals can cause Nafion polymer chain scission, thus leading to membrane degradation such as pinholes.

[0026] Figure 2 Depicts Figure 1A schematic exploded side view of a portion of the anode side 12 of the fuel cell 10 is shown. Figure 1 and 2 The mechanism of free radical generation and membrane degradation is depicted. Metal ions can be released from BPP 16 when exposed to acidic media. For example, Fe 3+ Ions can be released from BPP 16 via the following reaction equation:

[0027]

[0028] As shown by arrow 34, metal ions are released from the BPP 16 and transported along with the reaction medium (e.g., wet H2) through the GDL 24 to the anode 26 and membrane 32. ORR produces water, which migrates through the fuel cell 10 as shown by arrows 36 and 38. This water can wet the H2 from the anode side 12. The metal ions can bind to the membrane material in the membrane 32 and the anode 26. Figure 2 As shown, Fe 3+ The ions bind to the Nafion ionomer and catalyze the formation of hydrogen peroxide (ORR byproduct) according to a Fenton-like reaction. ● OH radicals are shown below and are indicated by reference numeral 40 .

[0029]

[0030] A continuous supply of metal ions can be provided by oxidation of the metal ions in the presence of H2O2. Figure 2 As shown, Fe 3+ The continuous supply of Fe 2+ Oxidized to Fe 3+ to provide, as shown in the following reaction equation and indicated by reference numeral 42, or by continuous oxidation of stainless steel.

[0031]

[0032] Produced ● OH radicals break ionomer polymer chains (e.g., Nafion ionomer chains), thereby degrading the ionomer and membrane 32, e.g. Figure 2 The degradation in 44 is shown.

[0033] A known method to mitigate membrane degradation is to provide CeO2 in the membrane and / or catalyst layer. 3+ Ions in the catalytic cycle ● OH radicals react to scavenge harmful free radicals. Figure 3is a schematic exploded side view of the known method implemented in the fuel cell 10. CeO2 particles 46 can be incorporated into the anode 26 at an anode concentration and / or into the membrane 32 at a membrane concentration. The membrane concentration can be any of the following values ​​or within a range of any two of the following values: 10 -4 , 10 -3 , 10 -2 , 1 and 10 wt %. According to this known method, the following reaction mechanism is used to remove ● OH radicals:

[0034]

[0035] In one or more embodiments, a novel method for ion scavenging in PEMFCs to mitigate membrane degradation is disclosed. The novel method may include incorporating an ion scavenger into the anode side of the fuel cell. The metal ion scavenging material may be one or more cation-intercalating host materials and / or one or more chelating ligands. The ion scavenger may be configured to remove and / or chelate ions generated by corrosion of BPP to mitigate degradation of the fuel cell membrane and ionomer.

[0036] like Figure 4 As shown, an ion scavenger 48 may be incorporated into the anode 26. The ion scavenger 48 may be a cation intercalating host (IH) configured to intercalate Fe 3+ ions, as shown by arrow 50 and represented by the following reaction equation, thereby reducing ● OH radical formation and membrane degradation.

[0037]

[0038] The intercalation host material is configured to allow metal ions to be reversibly incorporated or intercalated into an intercalation host material having multiple layers, wherein the intercalation occurs between adjacent layers. The intercalation may not include chemical bonding of the metal ions to the intercalation host material, but rather physical insertion of the metal ions into adjacent layers.

[0039] The embedded host material can be but not limited to the following materials: TiS2, ZrS2, TiSe2, MoS2, VOPO4·H2O, MnPS3, H2Ti4O9, H4Nb6O 17 , MoO3 and graphite. The cation-intercalated host material can also be a general order of [AcB ZAcB] n A layered double hydroxide, wherein c represents a metal cation layer, A and B are hydroxide anion layers, and Z is a layer of other anions and neutral molecules, is given by the formula Indicates that X n- is one or more intercalated ions, M 2+It can be a metal cation (such as Ca 2+ Mg 2+ 、Mn 2+ 、Fe 2+ 、Co 2+ 、Ni 2+ 、Cu 2+ or Zn 2+ ), and N 3+ M can be a trivalent cation (eg, the same metal as M). The value of x can be any of the following values ​​or a range between any two of the following values: 0.2, 0.25, 0.3, 0.35, 0.4, 0.45, and 0.5.

[0040] The embedding host can also be Prussian blue (ferric hexacyanoferrate (HCF)) or a Prussian blue analog (e.g., a compound based on hexacyanomagnate (HCM)). Non-limiting examples of HCM-based compounds include NiHCF, NiCuHCF, and MnHCM. The embedding host material can also be a polymer material, such as polyaniline (PANI), 3-hexylthiophene, polypyrrole. The embedding host material can be any single material identified above or any combination thereof.

[0041] The ion scavenger 48 may be one or more chelating agents configured to bind to metal ions released by the BPP 16 and / or 20, thereby mitigating ● The formation of OH radicals and membrane degradation. Non-limiting examples of chelating agents according to one or more embodiments include crown ethers (e.g., 1,4,7,10-tetraoxacyclododecane, 1,4,7,10,13-pentaoxacyclopentadecane, 1,4,7,10,13,16-hexaoxacyclooctadecane), acids (e.g., gluconic acid (C6H 12 O7), porphyrins, protoporphyrin derivatives, ethylenediamine-N,N'-bis(2-hydroxyphenylacetic acid) (o,o-EDDHA) and its analogs, tetraethylenetetramine, triethylenetetramine and aminopolycarboxylic acids such as ethylenediaminetetraacetic acid (EDTA), nitrilotriacetic acid (C6H9NO6) (NTA), trimethylenediaminetetraacetic acid, 1,2-dimethylethylenediaminetetraacetic acid, H4L (DMEDTA), ethylenebis(oxyethylenenitrilo)tetraacetic acid (EGTA) and oxybis(ethylenenitrilo)tetraacetic acid (EEDTA)).

[0042] Figure 4 Ion scavenger 48 is depicted dispersed within anode 26. In other embodiments, ion scavenger 48 may be dispersed differently within fuel cell 10 (eg, anode side 12). The dispersion methods of one or more embodiments may be combined.

[0043] In one or more embodiments, an ion scavenger may be incorporated as an interface layer between the BPP and the GDL (e.g., at the interface between the GDL 24 and the BPP 16 on the anode side 12 and / or at the interface between the GDL 28 and the BPP 20 on the cathode side 12). In one embodiment, the interface layer may be discrete such that the ion scavenger is not included in the GDL or BPP. The incorporation may be a coating at the interface between the BPP and the GDL and on the GDL. The coating may cover the entire surface area of ​​the GDL and / or the BPP. Alternatively, the coating may cover a certain percentage of each or both surfaces of the GDL and / or the BPP. The coverage percentage may be any of the following values ​​or within a range of any two of the following values: 0.1, 1, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, and 100%. The average thickness of the coating can be any of the following values ​​or a range of any two of the following values: 0.1, 1, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, and 100 μm. The coating can be formed solely of the ion scavenger or can be mixed with other materials such as conductive carbon (e.g., Vulcan, Ketjenblack, or a combination thereof) and a binder (e.g., PTFE, PVDF, or a combination thereof).

[0044] In one or more embodiments, an ion scavenging material can be incorporated into a GDL (e.g., GDL 24). The ion scavenging material can be well dispersed within the GDL so that the distance between each individual particle is less than the thickness of the GDL to enable the scavenging process to be effective. The loading of the ion scavenging material can be any of the following values ​​or within a range of any two of the following values: 0.01, 0.05, 0.1, 10, 50, and 100 mg / cm 2 .

[0045] In one or more embodiments, the fuel cell 10 includes a microporous layer (MPL) located between the GDL and the electrode. For example, the MPL can be located between the GDL 28 and the cathode 30. As another example, the MPL can be located between the GDL 24 and the anode 26. In one or more embodiments, an ion scavenger can be incorporated into one or more MPLs. The ion scavenger can be well dispersed within the MPL so that the distance between each individual particle is less than the thickness of the MPL to enable the scavenging process to be effective. The loading of the ion scavenger can be any of the following values ​​or within the range of any two of the following values: 0.01, 0.05, 0.1, 10, 50, and 100 mg / cm 2 .

[0046] In one or more embodiments, an ion scavenger can be incorporated into an electrode layer (e.g., anode 26 or cathode 30). The ion scavenger can be well dispersed within the electrode layer so that the distance between each individual particle is less than the thickness of the electrode layer to allow the scavenging process to be effective. The loading of the ion scavenger can be any of the following values ​​or within a range of any two of the following values: 0.01, 0.05, 0.1, 10, 50, and 100 mg / cm 2 .

[0047] In addition to the active material within each electrode, one or both electrode layers may include one or more conductive agents, one or more polymer binders and / or one or more other components. One or both electrode layers may include active material in any of the following amounts or within the range of any two of the following amounts: 60, 70, 75, 95, 97 and 99 weight percent, based on the total weight of the electrode layer. One or both electrode layers may include one or more conductive agents in any of the following amounts or within the range of any two of the following amounts: 1, 2.5, 5, 20, 30 and 40 weight percent, based on the total weight of the electrode layer. One or both electrodes may include one or more polymer binders in any of the following amounts or within the range of any two of the following amounts: 1, 2.5, 5, 15, 20 and 30 weight percent, based on the total weight of the electrode layer.

[0048] Non-limiting examples of the conductive agent include carbon black, conductive carbon black, amorphous carbon, carbon fiber, quaternary ammonium salts, alkyl sulfonates, halogen-free cationic compounds, and / or combinations thereof.

[0049] Non-limiting examples of polymeric binders include polyvinylidene fluoride (PVdF), polyacrylonitrile (PAN), poly(methyl methacrylate) (PMMA), polyethylene glycol (PEO), polyimide, polydopamine, poly(ethylene glycol) diacrylate, polymethylpentene, nylon, metal-aramid, polyetherimide, copolyester, polyetherketone, carboxymethyl cellulose, styrene-butadiene rubber (SBR), copolymers and blends such as poly(vinylidene fluoride-hexafluoropropylene) (PVdF-HFP), poly(vinylidene fluoride- chlorotrifluoroethylene) (PVdF-CTFE), poly(methyl methacrylate-vinyl acetate) (PMMA-VAc), poly(ethylene glycol) diacrylate (PEGDA), poly(methyl methacrylate-acrylonitrile-vinyl acetate) (PMMA-AN-VAc), poly(methyl methacrylate-co-butyl acrylate) (PMMA-co-BA), poly(3,4-ethylenedioxythiophene) polystyrene sulfonate-co-polyethylene glycol (PEDOT-co-PEG) and / or combinations thereof.

[0050] The electrode containing the embedded body can be configured to operate within a water stability window. For neutral water with a pH of about 7-8, the water stability window can be any of the following values ​​or a range of any two of the following values: -0.5, -0.4, -0.3, 0, 0.9, 1.1, 1.2, and 1.5 V compared to the standard hydrogen electrode (SHE) (or relative to Na / Na + Lower pH values ​​shift the voltage higher (up to +0.4 V at pH 0), while higher pH values ​​shift the voltage lower (down to -0.4 V at pH 14).

[0051] The electrode layer area can be any of the following values ​​or any two of the following values: 10, 50, 100, 250, 350, and 500 cm 2 . The electrode layer thickness may be any of the following values ​​or within a range of any two of the following values: 2.5, 5, 10, 300, 400, and 500 µm, depending on the choice of electrode material, porosity, tortuosity, viscosity of the slurry containing the electrode material, and / or the actual composition ratio of (one or more) active material:binder:carbon. The porosity of the electrode layer may be any of the following values ​​or within a range of any two of the following values: 20, 30, 40, 60, 70, and 80%. The electrode density of the electrode layer may be any of the following values ​​or within a range of any two of the following values: 0.1, 0.25, 0.5, 3, 4, and 5 g / cm 3 , which depends on the particle size, microstructure, material hardness and the amount of additive carbon in the electrode system.

[0052] In one or more embodiments, an ion scavenger may be incorporated as an interface layer between the GDL and the electrode layer (e.g., at the interface between the GDL 24 and the anode 26 and / or the interface between the GDL 28 and the cathode 30). In one embodiment, the interface layer may be discrete such that the ion scavenger is not included in the GDL or the electrode layer. The incorporation may be a coating at the interface between the GDL and the electrode and on the GDL. The coating may cover the entire surface area of ​​the GDL and / or the electrode. Alternatively, the coating may cover a certain percentage of each or both surfaces of the GDL and / or the electrode. The coverage percentage may be any of the following values ​​or within the range of any two of the following values: 0.1, 1, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, and 100%. The average thickness of the coating can be any of the following values ​​or a range of any two of the following values: 0.1, 1, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, and 100 μm. The coating can be formed solely of the metal ion scavenging material or can be mixed with other materials such as conductive carbon (e.g., Vulcan, Ketjenblack, or a combination thereof) and a binder (e.g., PTFE, PVDF, or a combination thereof).

[0053] The actual storage capacity of the embedded body may vary depending on the operating voltage conditions, the concentration of ions present, the overall chemical composition, the acidity, and the ohmic or any other type of resistance within the fuel cell. The actual storage capacity may be any of the following values ​​or a range between any two of the following values: 1, 10, 25, 50, 100, 150, 200, 250, and 300 mAh / g.

[0054] The cation intercalation host can intercalate ions when the potential of the cation intercalation host is lower than the redox potential of the active redox pair in the cation intercalation host material. In one embodiment, the potential of the anode catalyst layer (~0 V relative to the SHE) is low enough to drive the cation intercalation reaction. Alternatively, the ion intercalation reaction can be driven by a controller algorithm that controls the effective voltage, for example, by causing the electrode potential to reach the respective voltage relative to the counter electrode or the reference electrode. The ion removal of one or more embodiments can be completed at one or two electrodes. In one embodiment, since the cathode is typically at a voltage higher than the intercalation potential (~0.6 – 0.8 V), the ion intercalation on the cathode side is performed by a controller algorithm that controls the effective voltage.

[0055] The ion removal process can be performed during normal fuel cell operation or as a periodic ion cleaning step. The periodic ion cleaning step can be applied after a given amount of operating time or after specific events, such as shutdown and / or startup cycles. In one or more embodiments, if the intercalation body is saturated with ions, a "cleaning step" or "regeneration step" can be performed, in which the respective electrodes containing the fully or partially saturated intercalation body are held at a high voltage, such as 0.6 V or higher relative to the SHE, to drive deintercalation. The intercalation and deintercalation operations can be performed according to a controller configured to determine when specific fuel cell operating conditions are met.

[0056] The process disclosed herein, method or algorithm can be transferred to / executed by a processing device, a controller or a computer, which may include any existing programmable electronic control unit or a dedicated electronic control unit. Similarly, the process, method or algorithm can be stored as data and instructions that can be executed by a controller or a computer in many forms, including but not limited to information permanently stored on a non-writable storage medium such as a ROM device and information variably stored on a writable storage medium such as a floppy disk, a magnetic tape, a CD, a RAM device and other magnetic and optical media. The process, method or algorithm can also be implemented in a software executable object. Alternatively, appropriate hardware components, such as an application specific integrated circuit (ASIC), a field programmable gate array (FPGA), a state machine, a controller or other hardware components or equipment, or a combination of hardware, software and firmware components can be used to embody the process, method or algorithm in whole or in part.

[0057] Although exemplary embodiments have been described above, it is not intended that these embodiments describe all possible forms encompassed by the claims. The words used in the specification are descriptive rather than restrictive, and it should be understood that various changes may be made without departing from the spirit and scope of the present disclosure. As previously mentioned, the features of the various embodiments may be combined to form other embodiments of the present invention that may not be explicitly described or illustrated. Although the various embodiments may be described as providing advantages or being superior to other embodiments or prior art embodiments in terms of one or more desired characteristics, those skilled in the art will recognize that one or more features or characteristics may be compromised to achieve the desired overall system properties, depending on the specific application and implementation. These properties may include, but are not limited to, cost, strength, durability, life cycle cost, marketability, appearance, packaging, size, applicability, weight, manufacturability, ease of assembly, etc. Therefore, to the extent that any embodiment is described as being less desirable than other embodiments or prior art embodiments in terms of one or more characteristics, these embodiments are not outside the scope of the present disclosure and may be desirable for a particular application.

Claims

1. A fuel cell comprising: an anode side comprising an anode, an anode-side gas diffusion layer, and an anode-side bipolar plate formed of a first metal material; a cathode side comprising a cathode, a cathode-side gas diffusion layer, and a cathode-side bipolar plate formed of a second metal material; a membrane positioned between an anode side and a cathode side, the membrane having a first side and a second side, the anode being positioned between the anode side gas diffusion layer and the membrane, the cathode being positioned between the cathode side gas diffusion layer and the membrane, the anode side bipolar plate being positioned adjacent to the anode side gas diffusion layer and opposite to the membrane, and the cathode side bipolar plate being positioned adjacent to the cathode side gas diffusion layer and opposite to the membrane; and an intercalation body located in the anode side and / or the cathode side and configured to intercalate metal ions formed of the first and / or second metal material, wherein the intercalation host comprises a layered double hydroxide having the general sequence [AcBZAcB] n , where c represents a layer of metal cations, A and B are layers of hydroxide anions, and Z is a layer of other anions and neutral molecules.

2. The fuel cell according to claim 1, wherein The anode and / or cathode comprises one or more active materials, one or more conductive agents, one or more polymer binders, and / or one or more other components.

3. The fuel cell according to claim 1, wherein The embedded body is incorporated into the anode and / or cathode.

4. The fuel cell according to claim 3, wherein The loading of the intercalation bodies incorporated into the anode and / or cathode is between 0.01 and 100 mg / cm 2 within the range.

5. The fuel cell according to claim 3, wherein The embedding body is configured to operate within a water stability window ranging from -0.5 to 1.5 V compared to a standard hydrogen electrode.

6. The fuel cell according to claim 1, wherein The embedding body comprises Prussian blue or an analog thereof.

7. A fuel cell comprising: an anode side comprising an anode, an anode-side gas diffusion layer, and an anode-side bipolar plate formed of a first metal material; a cathode side comprising a cathode, a cathode-side gas diffusion layer, and a cathode-side bipolar plate formed of a second metal material; a membrane positioned between an anode side and a cathode side, the membrane having a first side and a second side, the anode being positioned between the anode side gas diffusion layer and the membrane, the cathode being positioned between the cathode side gas diffusion layer and the membrane, the anode side bipolar plate being positioned adjacent to the anode side gas diffusion layer and opposite to the membrane, and the cathode side bipolar plate being positioned adjacent to the cathode side gas diffusion layer and opposite to the membrane; and an embedding body configured to embed metal ions formed of the first and / or second metal material, wherein the intercalation host comprises a layered double hydroxide having the general sequence [AcBZAcB] n , where c represents a layer of metal cations, A and B are layers of hydroxide anions, and Z is a layer of other anions and neutral molecules.

8. The fuel cell according to claim 7, wherein The embedding body is disposed in an embedding body layer respectively located between the anode-side gas diffusion layer and / or the cathode-side gas diffusion layer and the anode-side bipolar plate and / or the cathode-side bipolar plate.

9. The fuel cell according to claim 7, wherein The embedding body is incorporated into the anode-side gas diffusion layer and / or the cathode-side gas diffusion layer.

10. The fuel cell according to claim 7, further comprising an anode-side microporous layer located between the anode-side gas diffusion layer and the anode, and a cathode-side microporous layer located between the cathode-side gas diffusion layer and the cathode, the embedded body being incorporated into the anode microporous layer and / or the cathode microporous layer.

11. The fuel cell according to claim 7, wherein The embedding body is disposed in an embedding body layer located between the anode-side gas diffusion layer and / or cathode-side gas diffusion layer and the anode and / or cathode, respectively.

12. The fuel cell according to claim 7, wherein The embedding body comprises Prussian blue or an analog thereof.

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