Electrically Isolated Electrochemical Cell and Method of Manufacturing the Same

This application is based upon and claims the benefit of priority under 35 U.S.C. § 119(e) to U.S. Provisional Application No. 63/645,472, filed May 10, 2024, the entire contents of all of which are incorporated herein by reference in their entirety.

The present disclosure relates to electrochemical cells and stacks, more particularly to components for electrochemical cells and stacks designed for electrical isolation, low leak rates, small cell pitch, and high-speed manufacturing.

Electrochemical cells are devices for inducing chemical reactions using electricity or generating electricity using chemical reactions. If electricity is the output, the cells may be considered fuel cells or expander cells, depending on the chemical product. If electricity is the input, the cells may be considered electrolyzer cells, compressor cells or purifier cells, depending on the chemical product. For example, an electrolyzer takes electrical energy and stores it in a fuel such as hydrogen by splitting water into its constituent elements. In contrast, a fuel cell may be thought of essentially as an electrolyzer running in reverse—hydrogen and oxygen are provided to the cell, which then combines these molecules to form water, releasing electrical energy in the process. Other chemical reactions may be promoted by use of an electrochemical cell or stack of cells such as the reduction of carbon dioxide into carbon monoxide, ethylene, or ethylene glycol, the reduction of nitrogen into ammonia or associated compounds, the formation of hydrogen peroxide from water and oxygen or the extraction of lithium from lithium brine solutions. The basic elements of these devices are two electrodes, an ion-conducting electrolyte, and an ion-permeable layer separating the two electrodes, although it is possible to operate an electrolyzer or fuel cell in a membrane-less configuration, as well. Electrochemical cells may also include a separator between the electrodes to prevent products from mixing inside of the cell. In the case of solid-electrolytic cells, the membrane and separator may be combined into a unitized, solid, ion-conducting layer. A complete electrochemical cell may also include flow fields for delivering reactants to the electrodes, seals for isolating reactants from each other and the environment, and one or more impermeable separator plates, also referred to as bipolar plates, for isolating one cell from adjacent cells in a stack and, in certain embodiments, for containing a separate cooling fluid for thermal management of the cell. Impermeability may be defined as a material having a permeability coefficient for a particular gas species of <1.0×10[mol gas/(m s Pa)].

A variety of electrolytes can be used in electrochemical cells, including proton exchange membranes, anion exchange membranes, solid-oxide ceramic membranes, and liquid alkaline solutions such as potassium hydroxide and sodium hydroxide. Different electrolytes demand different operating conditions, and each comes with its own benefits and limitations. Advantages of proton and anion exchange membrane electrolytes may include relatively low operating temperature and a cell that can be constructed using a unitized-layer electrolyte/membrane. Electrolyzers using such membranes have the distinct advantage over other electrolyzers of being able to operate using relatively pure, liquid water, rather than a caustic solution or water vapor as a feed stock, thereby greatly simplifying the balance of system in practice. Relatively pure water may be defined as water containing no more than 5% by weight of elements other than hydrogen and oxygen. Such electrolyzers may also be operated without liquid water on the cathode, allowing production of hydrogen in a gas phase having non-zero vapor-phase moisture content. A non-zero vapor-phase moisture content may be defined as gas containing more than one part per million water vapor, by volume.

The impact of carbon dioxide on global climate change is well-documented. As society's efforts to address global climate change accelerate, the need for deep decarbonization of most or all human energy use has become clear and urgent. The use of hydrogen as a carbon-free energy carrier is essential to reaching certain segments of human industry that are difficult or impossible to decarbonize directly with electricity. Examples of such segments include steel production, fertilizer manufacturing, construction, and heavy transport such as trucking, marine and air vehicles. In addition to these segments, the energy density and stable storage characteristics of hydrogen has made it the most viable candidate for seasonal-scale energy storage and establishment of grid resiliency using only renewable electricity, which will be required for complete conversion of energy use to carbon-free sources. These and other benefits have driven a high level of interest in “green hydrogen” production.

Hydrogen is given a “green” label if it is produced by electrolysis from renewable electricity (wind, solar, hydropower, etc.). Other “colors” of hydrogen are conventionally assigned to other energy sources. The scale required to meet the potential demand for green hydrogen in the future global energy system is daunting. Production capacities for electrolyzers will need to increase by many orders of magnitude and their costs reduced by a factor of ten or more over the next decade to meet such demand. Up to now, production of hydrogen electrolyzers has been a niche industry with small systems and limited deployments based on cells and stacks designed for research and development. Only minor considerations have been made for the speed of manufacturing necessary to produce and assemble cells and stacks at a rate commensurate with society's eventual need.

Recognizing the urgent need for innovative electrolyzer technology in fighting climate change, the present application is directed toward components for a scalable electrolysis cell and stack, and method of high-speed manufacturing those components. Embodiments of the present application are directed to the design and manufacturing of critical elements for these cells and stacks including bipolar plates, hydrogen and water seals, flow fields, membranes, reinforcing sub-gaskets, and efficient assembly of these components into a unitized cell. The present disclosure includes innovative designs for component geometry, innovative materials, and dimensions that overcome limitations of prior art electrochemical cells and stacks. These limitations include:

The description below will focus on water electrolysis for hydrogen production for clarity, but may be applied to other electrochemical processes such as fuel cells, hydrogen compressors, hydrogen expanders, carbon dioxide electrolyzers, ammonia electrolyzers, and lithium brine electrolyzers, by one skilled in the art.

The basic process of water electrolysis involves providing water to a positively charged anode and conducting ions between the anode and a negatively charged cathode. Oxygen gas is produced at the anode while hydrogen gas is produced at the cathode. The particular ion conducted between the anode and the cathode depends on the electrolyte used. In an acidic cell, positively charged hydronium ions (HO) are conducted from the anode to the cathode. In an alkaline cell, negatively charged hydroxide ions (OH) are conducted from the cathode to the anode. In both systems, the overall reaction is the same: (2)HO(/)→(2)H(g)+O(g). Electricity must be provided to drive the reaction. The open-circuit, or thermo-neutral, voltage for the basic reaction of hydrogen to liquid water is 1.481 V, therefore a voltage higher than 1.481 V must be applied to a hydrogen electrolysis cell fed with liquid water to cause the reaction to progress (as discussed below, an overpotential is usually required for the reaction to proceed at acceptable rates). The size (i.e., active area) of the cell determines the rate of hydrogen/oxygen production from one cell at a given applied voltage. The total current required for a particular applied voltage may be proportional to the active area of the cell. In practical systems, multiple cells may be “stacked” on top of each other to increase production capacity. This stacking of cells results in the need to apply a higher voltage (integer multiple of the cell count) to drive the reaction. For example, a single cell of 1000 cmactive area may produce the same hydrogen flow as two stacked cells of 500 cm, but the 500 cmstack will require an input of 2 times the voltage and ½ of the current. Flexibility in selecting required voltage and current may be a significant consideration in the design and cost of a total electrolysis system. For example, power supplies for higher current and lower voltage may be more expensive than those for higher voltage and lower current due to the size of the required electrical conductors and additional materials required for their construction. Therefore, an easily scalable cell active area is a significant advantage for cost and flexibility of deployment.

The elements of a hydrogen electrolyzer stack may include a stack of repeating components (configured as repeating “cells”) and a system of non-repeating components to hold the cells together in a stacked configuration. As the name implies, the repeating components are those whose quantity scales with stack height and may typically include the membrane/electrolyte, anode and cathode electrodes, anode and cathode electrode reinforcement layers, water and hydrogen flow fields, water and hydrogen seals, and a bipolar cell separator plate. The non-repeating components may typically include end units and a mechanical system for maintaining compression on the stack of repeating components (the “stack core”), along with power terminals, electrical isolators, fluid distribution and/or drain/purge manifolds. The stack compression system may include compliant elements such as tension members, springs, and adjustable members (rods, bolts, wedges, etc.) to generate and maintain compressive loading in the stack core. This compression of the stack core may be essential to ensure both electrical contact and fluid sealing between individual cells and with the end units. In a typical electrolyzer stack, the compliant elements may be located outside the stack core, as the core itself may be relatively “stiff” mechanically. In this case a relatively “soft”, or compliant, compression system, external to the stack core, may be required to ensure ongoing compressive load is maintained as the stack height changes with time or temperature or pressure. These external elements may be large and/or expensive and/or cumbersome for manufacturing. Alternately, repeating components with built-in compliance may enable a designer to minimize or eliminate the need for substantial external springs, rods, bolts, etc., leading to an advantage in cost, size, and speed of assembly for the stack. In this context, compliance may be defined as the inverse of an effective elastic spring constant along a z-axis, which is an axis aligned with the axis of stacking cells (i.e., change in “z” [mm] per unit of applied force [kgf]).

The present disclosure is directed toward novel designs and methods of manufacturing for electrochemical cell components which provide improved electrical isolation within the liquid-containing plenums of a stack of such cells. In a typical electrochemical stack, electrically conductive components such as the bipolar separator plate may come in contact with the liquid plenums. When voltage is applied to the stack, these charged plates may cause reactions directly in the liquid plenum, an undesired condition as such a reaction reduces the efficiency of the stack and, in the case of electrolysis, also generates reaction products where they are not wanted. For example, in a water electrolyzer, plenum electrolysis caused by live plates contacting the water plenums may result in hydrogen generation on the anode side, which may result in a safety hazard if the reaction rate is too high. The reaction rate in the plenums may be reduced by increasing the distance between the conductive components contacting the plenum. This is typically accomplished by making the cells thicker (i.e., a greater cell “pitch”), which is undesirable from cost and size perspective for an electrolyzer. The higher the conductivity of the liquid in the plenum, the larger the cell pitch must be to maintain an acceptable reaction rate. Alkaline water electrolyzers using Potassium Hydroxide at high concentrations (up to 7 molar) typically have cell pitches greater than 10 mm, even up to 20 mm. Mathematical modelling (see) shows that, with highly conductive electrolyte, a cell pitch of less than 5 mm may result in a parasitic current through the water plenums of greater than 10%. PEM fuel cells on the other hand may have cell pitches as low as 1.0-1.5 mm, but these fuel cell stacks require very low conductivity for the liquid filling the plenums (<10 μS/cm). This requirement for very low conductivity may increase the cost, complexity and maintenance requirements for such systems. The subject matter of the present application overcomes these limitations by providing components whose materials and geometry decouples the conduction path length from the cell pitch.

The present disclosure is also directed toward novel designs and methods of manufacturing electrochemical cell components which provide for hermetic sealing of critical fluid chambers within a cell. An electrolysis cell typically requires three seals: 1) cathode (e.g., hydrogen) to the environment; 2) anode (e.g., water+oxygen) to the environment; and 3) cross-leakage between cathode and anode within the cell. Typical prior art cells rely on compressible gaskets and seals to be engaged at all sealing interfaces through the compression of the stack. This sealing approach can drive the need for tight dimensional tolerances, which may significantly increase cost. This approach may also force design decisions that require large cell pitch to fit compressible seals into the cell. The subject matter of the present application overcomes these limitations by providing materials and geometry that allow hermetic seals to be created during manufacturing. A hermetic seal may be defined as a bond between two layers wherein the bond is gastight and of equal or greater mechanical strength than the materials being bonded. Gastight may be defined as a material or bond having a leakage coefficient for a particular gas species of <3.0×10[mol gas/(m s Pa)]. One example of a hermetic seal is a hot-melt seal between two thermoplastic materials wherein the materials mix in a molten state at the bond line to form a single, mixed material after cooling and solidifying. The subject matter of the present application provides materials and geometry for cell components that allow such a hermetic seal to be created for all three seal regions defined above.

The present disclosure is also directed toward novel materials and methods of manufacturing electrochemical cell components which provide simultaneously for speed and ease of manufacturing, and adequate mechanical properties in the service environment of an operating electrochemical cell. During fabrication of cell components, it may be desirable to use hot-melt lamination processes. It may further be desired to have a relatively low melt temperature for these components to allow simpler machinery and faster line speeds. However, materials selected must also withstand the electrochemical cell and stack operating environment and mechanical properties in-situ must be adequate to resist creeping or deforming under mechanical stress at the operating temperature of the stack. It may be that materials with good hot melt properties for manufacturing processing have inadequate properties at operating conditions. The subject matter of the present application provides a material for cell components which contains a cross-linker that can increase the temperature resistance of the material only after it has been processed into cells. In this way the cross-linkable material may be processed into cells at relatively low temperatures and then converted into a material with higher temperature properties after the component or cell fabrication is finished. One such cross-linker may be a photo-initiated cross-linker that enables the cross-linking to be controlled as a desired point in the manufacturing process. Examples of materials containing photo-initiated cross-linkers include LOCTITE AA 3106 acrylated urethane, LOCTITE AA 3526 modified acrylic, and LOCTITE SI 5083 acetoxy silicone.

The present disclosure is also directed toward novel designs and methods of manufacturing electrochemical cell components which provide for precise location and assembly unitization to simplify and reduce variation during cell stacking operations. A typical electrochemical cell may contain 12 discrete layers or more. A typical electrochemical stack may contain as many as 400 individual cells, or more. Handling potentially more than 4,000 discrete components to handle and position during cell stack creates high risk for misalignment, which may result in a non-working stack. Discovering failures only after the stack is built may result in significant additional cost to diagnose and repair. Additionally, decompressing and then recompressing an electrochemical stack may result in a performance loss relative to the performance achievable with a single compression cycle. Preassembly of discrete components into unitized assemblies with precise component alignment is a typical method used to address these stacking problems. However, reliance on traditional compressible seals for the critical sealing interfaces limits the extent to which unitization can be taken, and multiple discrete sub-assemblies for each cell may still need to be aligned during cell stacking, each with the risk of failure. The subject matter of the present application provides materials, geometry, and methods of fabrication that enable unitization of complete cells with precise placement of all discrete components and the integration of testable, hermetic seals prior to cell stacking. These materials, geometries, and methods overcome prior art limitations and minimize the potential failures at the stack level.

For convenience we may define a cartesian coordinate system with perpendicular x-y-z axes where “x” is parallel to the general direction of water flow through the cell, “y” is perpendicular to x, but in the same plane defined by a single cell, and “z” is generally parallel to the direction of stacking of the cells. In this context the compression system generally works to apply compressive load along the z axis, holding the cells and their various repeating components in contact with each other. Compliance of the stack core may then be measured along a z-axis, so defined.

It is to be understood that both the foregoing general descriptions and the following detailed descriptions are exemplary and explanatory only and not restrictive of the disclosure, as claimed. Further objects, features, and advantages of the present application will become apparent from the detailed description of preferred embodiments which is set forth below, when considered together with the figures provided.

The present invention may be understood more readily by reference to the following detailed description of the preferred embodiments of the invention and the Examples included herein. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the invention pertains. As used herein, the following meanings apply unless otherwise indicated.

As used herein, the singular forms “a”, “an”, and “the” include plural references unless indicated otherwise. It is noted that in this disclosure, terms such as “comprises,” “comprised,” “comprising,” “contains,” “containing” and the like can have the meaning attributed to them in U.S. patent law; e.g., they can mean “includes,” “included,” “including” and the like. Terms such as “consisting essentially of’ and “consists essentially of’ have the meaning attributed to them in U.S. patent law, e.g., they allow for the inclusion of additional features or steps that do not detract from the novel or basic characteristics of the invention, i.e., they exclude additional unrecited features or steps that detract from the novel or basic characteristics of the invention. The terms “consists of’ and “consisting of’ have the meaning ascribed to them in U.S. patent law; namely, that these terms are closed ended. Accordingly, these terms refer to the inclusion of a particular features or step and the exclusion of all other features or steps.

The terms “about” or “approximate” and the like are synonymous and are used to indicate that the value modified by the term has an understood range associated with it, where the range can be ±20%, ±15%, ±10%, ±5%, or ±1%. The term “substantially” is used to indicate that a value is close to a targeted value, where close can mean, for example, the value is within 80% of the targeted value, within 85% of the targeted value, within 90% of the targeted value, within 95% of the targeted value, or within 99% of the targeted value.

The term “cell pitch” means the distance between repeating elements in adjacent cells within a stack, typically measured from the same location on one cell to the corresponding location on an adjacent cell.

The term “conduction path length” means the total distance that electrical current must travel through liquid (e.g. water) in a plenum between the conductive components of adjacent cells in a stack.

The term “edge extension” means the non-conductive region extending from the conductive area to the liquid plenum, designed to increase the electrical conduction path length between adjacent cells.

The term “unitized assembly” means a pre-assembled component comprising multiple discrete layers bonded together to form a single handling unit with precise alignment of all constituent components.

The term “liquid plenum” refers to a chamber or channel within a cell designed to contain and distribute liquid (typically water) throughout the cell and between cells in a stack.

The term “parasitic current” means undesired electrical current flowing through conductive liquid in the liquid plenums between adjacent cells in a stack, resulting in efficiency losses and potentially hazardous reactions.

The term “non-conductive” refers to a material having an electrical resistivity of at least 10ohm-meters (Ω·m) at standard temperature and pressure.

The “active area” of a cell means the area of an electrochemical cell where the desired electrochemical reaction occurs.

The term “hot-melt seal” means a hermetic seal formed by heating thermoplastic materials to their melting point, allowing them to flow together at the interface, and then cooling to form a single, homogeneous material without a distinct bond line.

The term “cross-linkable formulation” means a material composition that can undergo a chemical reaction to form cross-links between polymer chains, thereby increasing its mechanical strength, temperature resistance, and chemical stability after initial processing.

The term “photo-initiated cross-linking” means a cross-linking process activated by exposure to light of specific wavelengths (typically ultraviolet), allowing controlled timing of the cross-linking reaction during manufacturing.

The term “bonding promoter” means a chemical compound or treatment applied to a surface to enhance adhesion between dissimilar materials during a bonding process.

Detailed descriptions of several preferred embodiments will now be given in reference to the accompanying drawings. Although descriptions relate to water electrolysis, it is understood that the described features, components, and methods are applicable and adaptable, by those skilled in the art, to other electrochemical technologies including reduction of carbon dioxide into carbon monoxide, ethylene, or ethylene glycol, the reduction of nitrogen into ammonia or associated compounds, the formation of hydrogen peroxide from water and oxygen or the extraction of lithium from lithium brine solutions, hydrogen compressors, hydrogen purifiers, and fuel cells.shows a cross section through the liquid-containing water plenums of a repeating stack of cells of a preferred embodiment of the present application (). A coordinate system is defined inillustrates an electrically conductive, impermeable separator (bipolar) plate;illustrates an electrically conductive, permeable, cathode chamber;represents an ionically-conductive separator membrane;illustrates an electrically conductive, permeable, anode chamber;illustrates a non-conductive cell edge extension with a length along an x-axis of(d_cond);illustrates a non-conductive cathode chamber seal embedded within the permeable cathode chamberand hermetically connected to edge extensionillustrates the liquid filling the water columns of the stack formed by the water plenums of each cell and the resulting connection between cells caused by this liquid column;illustrates the thickness, or “pitch” of a single cell within the stack of repeating cells;illustrates the resulting electrical path length between adjacent cells. Dimensionmay be equal to or greater than twice the edge extension length () and may not be a function of cell pitch (). Design choices for the edge extension length may allow a total conductive path length between adjacent cells to be 1 times the cell pitch, 1.5 times the cell pitch, 2 times the cell pitch, 3 times the cell pitch, 5 times the cell pitch, or 10 times the cell pitch.

shows a cross section through the liquid-containing water plenums of a repeating stack of cells of a prior art electrolyzer (). A coordinate system is defined inillustrates an electrically conductive, impermeable separator (bipolar) plate;illustrates the cathode flow channels ofrepresents an ionically-conductive separator membrane;illustrates the anode flow channels ofillustrates the liquid filling the water columns of the stack formed by the water plenums of each cell and the resulting connection between cells caused by this liquid column;illustrates the thickness, or “pitch” of a single cell within the stack of repeating cells;illustrates the resulting electrical path length between adjacent cells. Dimensionmay be substantially equal to the cell pitch () with limited ability to increase this path length without increasing the pitch of the cells, and thereby length of the stack.

shows an isometric view of a preferred embodiment electrolysis cell (). A coordinate system is defined in.illustrates one of a multitude of liquid plenums defined along the non-conductive edges of the cell.illustrates the conductive central area of the cell.illustrates the non-conductive border area of the cell. As cells are repeatedly stacked, the liquid plenumsmay align to create continuous liquid columns (,) that may electrically and/or ionically connect the edges of each cell along a stacking direction (aligned with the z-axis).

shows a plan view of a preferred embodiment electrolysis cell (). A coordinate system is defined in.illustrates one of a multitude of liquid plenums defined along the non-conductive edges of the cell.illustrates the conductive central area of the cell.illustrates the non-conductive border area of the cell.illustrates the edge extension length defined inwhich separates the liquid water column (,) created by liquid plenumsfrom the conductive central area of the cell.

shows a cross section of a cell of a preferred embodiment of the present application (). A coordinate system is defined in.illustrates a bipolar plate assembly (BPA) comprising a conductive, impermeable separator plate, a conductive, permeable cathode flow field, a non-conductive, edge extension, and a non-conductive, gas-tight cathode chamber sealembedded within cathode flow field;illustrates a membrane sub-gasket assembly (MSGA) comprising an ion conducting membrane, and one or more sub-gasket layers;illustrates a cathode electrode positioned between BPAand MSGA, and hermetically sealed adjacent to cathode chamberby hermetic bond line.illustrates an anode gasket assembly (AGA) comprising a conductive, permeable anode flow field, a conductive, permeable anode electrode, and a non-conductive, gas-tight anode chamber seal, wherein the anode chamber is hermetically seal at bond line. Upon stacking cells, only a single, cell-to-cell, non-hermetic seal must be engaged with compression of the cell stack as all seals within the unitized cell assemblyhave been hermetically bonded. Hermetic bonding atmay be accomplished using a hot-melt method, an ultrasonic welding method, an inductively heated bonding method, a laser welding method, a pressure sensitive adhesive method, a light-activated adhesive method, or an epoxy adhesive method.

shows an exploded, top isometric view of a preferred embodiment electrolysis cell (). A coordinate system is defined in.illustrates a half-cell assembly (HCA);illustrates an anode gasket assembly (AGA);illustrates the hermetically bonded area between assembliesand, enabling a within-cell hermetic seal of an anode chamber illustrated by area. Hermetic bonding atmay be accomplished using a hot-melt method, an ultrasonic welding method, an inductively heated bonding method, a laser welding method, a pressure sensitive adhesive method, a light-activated adhesive method, or an epoxy adhesive method. Hermetic bonding atmay be accomplished with a piecewise or continuous roll lamination method. Material selected for the various layers of the cell may include a cross-linkable formulation to enable initial components and assemblies to be fabricated with relative low temperature processes, while allowing post-fabrication treatment to enhance the mechanical properties to match the environmental and operating service conditions of the cell (e.g. the materials discussed previously). Such material formulation may include a light-reactive cross-linker and activator, a heat-reactive cross-linker and activator, a humidity-reactive cross-linker and activator, or a time-sensitive cross-linker and activator. A light-reactive cross-linker such as ultraviolet activated cross-linking may be advantageous for efficient manufacturing as cross-linking can be controlled and only executed at the desired process step. Such a desired cross-linking step may be performed after cell assemblyis fully unitized and all hermetic seals have been formed or may be performed for each sub-assembly or sub-component during manufacturing prior to unitization.

shows an exploded, bottom isometric view of the preferred embodiment electrolysis cell () of. A coordinate system is defined in.illustrates a half-cell assembly (HCA);illustrates an anode gasket assembly (AGA);illustrates the hermetically bonded area between assembliesand, enabling a within-cell hermetic seal of an anode chamber illustrated by area. Hermetic bonding atmay be accomplished using a hot-melt method, an ultrasonic welding method, an inductively heated bonding method, a laser welding method, a pressure sensitive adhesive method, a light-activated adhesive method, or an epoxy adhesive method. Hermetic bonding atmay be accomplished with a piecewise or continuous roll lamination method.

shows an exploded, top isometric view of a preferred embodiment anode gasket assembly (AGA) (). A coordinate system is defined in.illustrates a non-conductive, gas-tight anode chamber seal which defines a sealed anode chamber;illustrates an anode electrode;illustrates an electrically conductive, permeable anode flow field;illustrates a multiplicity of tab features included in anode chamber sealthat provide unitization of all components into a single assembly. Lamination of layers,, andmay be arranged to allow tabsto penetrate the porous layersand, effectively bonding all layers together into a unified assembly. Bonding atmay be accomplished using a hot-melt method, an ultrasonic welding method, an inductively heated bonding method, a laser welding method, a pressure sensitive adhesive method, a light-activated adhesive method, or an epoxy adhesive method. Bonding atmay be accomplished with a piecewise or continuous roll lamination method. All layers,, andin AGAmay be constructed from 2-dimensional patterns cut from sheets or rolls of material with substantially uniform thickness. This arrangement may provide significant manufacturing cost and speed advantages by enabling the use of high volume film extrusion or casting processes for raw materials and high-speed roll conversion processes for component, assembly, and cell fabrication. Material selected for chamber sealmay include a cross-linkable formulation to enable initial components to be fabricated with relative low temperature processes, while allowing post-fabrication treatment to enhance the mechanical properties to match the environmental and operating service conditions of the cell. Such material formulation may include a light-reactive cross-linker and activator, a heat-reactive cross-linker and activator, a humidity-reactive cross-linker and activator, or a time-sensitive cross-linker and activator. A light-reactive cross-linker such as ultraviolet activated cross-linking may be advantageous for efficient manufacturing as cross-linking can be controlled and only executed at the desired process step.

shows a plan view of a preferred embodiment anode gasket assembly (AGA) (). A coordinate system is defined in.illustrates a non-conductive, gas-tight anode chamber seal which defines a sealed anode chamber;illustrates an anode electrode;(not shown) illustrates an electrically conductive, permeable anode flow field;illustrates a multiplicity of tab features included in anode chamber sealthat provide unitization of all components into a single assembly. Lamination of layers,, andmay be arranged to allow tabsto penetrate the porous layersand, effectively bonding all layers together into a unified assembly. Bonding atmay be accomplished using a hot-melt method, an ultrasonic welding method, an inductively heated bonding method, a laser welding method, a pressure sensitive adhesive method, a light-activated adhesive method, or an epoxy adhesive method. Bonding atmay be accomplished with a piecewise or continuous roll lamination method.

shows an exploded, top isometric view of a preferred embodiment half-cell assembly (HCA) as manufactured (). A coordinate system is defined in.illustrates a bipolar plate assembly (BPA);illustrates a cathode electrode;illustrates a membrane sub-gasket assembly (MSGA).illustrates the hermetically bonded area betweenandforming a gas-tight, hermetically sealed cathode chamber. Cathode electrodemay be captured during fabrication within the boundary defined by cathode chamberbetweenand, becoming precisely fixed in position so as to not be allowed to shift position during subsequent handling or assembly steps. Bonding atmay be accomplished using a hot-melt method, an ultrasonic welding method, an inductively heated bonding method, a laser welding method, a pressure sensitive adhesive method, or an epoxy adhesive method. Bonding atmay be accomplished with a piecewise or continuous roll lamination method.

shows a plan view of a preferred embodiment half-cell assembly (HCA) as manufactured (). A coordinate system is defined in.illustrates a bipolar plate assembly (BPA) (underneath);illustrates a cathode electrode (below MSGA);illustrates a membrane sub-gasket assembly (MSGA).illustrates the hermetically bonded area betweenandforming a gas-tight, hermetically sealed cathode chamber. Cathode electrodemay be captured during fabrication within the boundary defined by cathode chamberbetweenand, becoming precisely fixed in position so as to not be allowed to shift position during subsequent handling or assembly steps. Bonding atmay be accomplished using a hot-melt method, an ultrasonic welding method, an inductively heated bonding method, a laser welding method, a pressure sensitive adhesive method, or an epoxy adhesive method. Bonding atmay be accomplished with a piecewise or continuous roll lamination method.

shows an exploded, top isometric view of a preferred embodiment half-cell assembly (HCA) after final processing (). A coordinate system is defined in.illustrates a bipolar plate assembly (BPA);illustrates a cathode electrode;illustrates a membrane sub-gasket assembly (MSGA).illustrates the hermetically bonded area betweenandforming a gas-tight, hermetically sealed cathode chamber. Cathode electrodemay be captured during fabrication within the boundary defined by cathode chamberbetweenand, becoming precisely fixed in position so as to not be allowed to shift position during subsequent handling or assembly steps. Bonding atmay be accomplished using a hot-melt method, an ultrasonic welding method, an inductively heated bonding method, a laser welding method, a pressure sensitive adhesive method, or an epoxy adhesive method. Bonding atmay be accomplished with a piecewise or continuous roll lamination method.

shows a plan view of a preferred embodiment half-cell assembly (HCA) after final processing (). A coordinate system is defined in.illustrates a bipolar plate assembly (BPA) (underneath);illustrates a cathode electrode (below MSGA);illustrates a membrane sub-gasket assembly (MSGA).illustrates the hermetically bonded area betweenandforming a gas-tight, hermetically sealed cathode chamber. Cathode electrodemay be captured during fabrication within the boundary defined by cathode chamberbetweenand, becoming precisely fixed in position so as to not be allowed to shift position during subsequent handling or assembly steps. Bonding atmay be accomplished using a hot-melt method, an ultrasonic welding method, an inductively heated bonding method, a laser welding method, a pressure sensitive adhesive method, or an epoxy adhesive method. Bonding atmay be accomplished with a piecewise or continuous roll lamination method.

shows an exploded, top isometric view of a preferred embodiment membrane sub-gasket assembly (MSGA) as manufactured (). A coordinate system is defined in.andillustrate non-conductive, gas-tight sub-gaskets;illustrates an ion-conducting membrane. All layers,, andin MSGAmay be constructed from 2-dimensional patterns cut from sheets or rolls of material with substantially uniform thickness. This arrangement may provide significant manufacturing cost and speed advantages by enabling the use of high volume film extrusion or casting processes for raw materials and high-speed roll conversion processes for component, assembly, and cell fabrication. Material selected for sub-gasketsandmay include a cross-linkable formulation to enable initial components to be fabricated with relative low temperature processes, while allowing post-fabrication treatment to enhance the mechanical properties to match the environmental and operating service conditions of the cell. Such material formulation may include a light-reactive cross-linker and activator, a heat-reactive cross-linker and activator, a humidity-reactive cross-linker and activator, or a time-sensitive cross-linker and activator. A light-reactive cross-linker such as ultraviolet activated cross-linking may be advantageous for efficient manufacturing as cross-linking can be controlled and only executed at the desired process step.

shows a plan view of a preferred embodiment membrane sub-gasket assembly (MSGA) as manufactured (). A coordinate system is defined in.andillustrate non-conductive, gas-tight sub-gaskets;illustrates an ion-conducting membrane;illustrates a hermetically bonded area between,, and. Hermetically bonded areamay ensure that gas or fluid cross-over between the cathode and anode chambers of the cell does not occur during operation of the electrolysis cell. Bonding atmay be accomplished using a hot-melt method, an ultrasonic welding method, an inductively heated bonding method, a laser welding method, a pressure sensitive adhesive method, or an epoxy adhesive method. Bonding atmay be accomplished with a piecewise or continuous roll lamination method.

shows an exploded, top isometric view of a preferred embodiment membrane sub-gasket assembly (MSGA) after final processing (). A coordinate system is defined in.andillustrate non-conductive, gas-tight sub-gaskets;illustrates an ion-conducting membrane.

shows a plan view of a preferred embodiment membrane sub-gasket assembly (MSGA) after final processing (). A coordinate system is defined in.andillustrate non-conductive, gas-tight sub-gaskets;illustrates an ion-conducting membrane;illustrates a hermetically bonded area between,, and. Hermetically bonded areamay ensure that gas or fluid cross-over between the cathode and anode chambers of the cell does not occur during operation of the electrolysis cell. Bonding atmay be accomplished using a hot-melt method, an ultrasonic welding method, an inductively heated bonding method, a laser welding method, a pressure sensitive adhesive method, or an epoxy adhesive method. Bonding atmay be accomplished with a piecewise or continuous roll lamination method.

shows an exploded, top isometric view of a preferred embodiment bipolar plate assembly (BPA) as manufactured (). A coordinate system is defined in.illustrates a conductive, non-permeable separator plate;illustrates a conductive, permeable cathode flow field;illustrates a non-conductive, gas-tight layer functioning as the cathode chamber seal and non-conductive edge area for the BPA. All layers,, andin BPAmay be constructed from 2-dimensional patterns cut from sheets or rolls of material with substantially uniform thickness. This arrangement may provide significant manufacturing cost and speed advantages by enabling the use of high volume film extrusion or casting processes for raw materials and high-speed roll conversion processes for component, assembly, and cell fabrication. Material selected for chamber sealmay include a cross-linkable formulation to enable initial components to be fabricated with relative low temperature processes, while allowing post-fabrication treatment to enhance the mechanical properties to match the environmental and operating service conditions of the cell. Such material formulation may include a light-reactive cross-linker and activator, a heat-reactive cross-linker and activator, a humidity-reactive cross-linker and activator, or a time-sensitive cross-linker and activator. A light-reactive cross-linker such as ultraviolet activated cross-linking may be advantageous for efficient manufacturing as cross-linking can be controlled and only executed at the desired process step. The surfaces of separator plateand/or cathode flow fieldmay be treated to enhance adhesive bonding strength with cathode chamber seal. Such enhancements may be accomplished by a chemical primer, a reactive chemical treatment such as phosphonic acid modification (e.g., 3-aminopropyl phosphonic acid), phenyl grafting, amine grafting, diazonium salt treatment, other acid or alkali treatment, physical roughening of the surface by surface finishes specified during raw material procurement, sanding, bead blasting, plasma or corona treatment, ozone treatment, surface oxidation, chemical etching, or laser etching, or other such bonding promotors available to industry. Bonding promoters may be included in the raw material formulation forsuch as maleated compounds including maleic anhydride, silanes, and phosphates.

shows a plan view of a preferred embodiment bipolar plate assembly (BPA) as manufactured (). A coordinate system is defined in.illustrates a conductive, non-permeable separator plate;illustrates a conductive, permeable cathode flow field (not shown);illustrates a non-conductive, gas-tight layer functioning as the cathode chamber sealand non-conductive edge area for the BPA. Cathode chamber seal areamay act to bond,, andinto a single, unitized component. Bonding atmay be accomplished using a hot-melt method, an ultrasonic welding method, an inductively heated bonding method, a laser welding method, a pressure sensitive adhesive method, or an epoxy adhesive method. Bonding atmay be accomplished with a piecewise or continuous roll lamination method.