Abstract: Oxygen electrodes, production methods and reversible, alkaline or anion exchange membrane (AEM) electrochemical devices are provided. The oxygen electrodes are operable in the reversible devices both as cathodes of a fuel cell supporting an oxygen reduction reaction (ORR), and as anodes of an electrolyzer supporting an oxygen evolution reaction (OER). The oxygen electrodes comprise a substrate layer which may be a porous transport layer (PTL), possibly coated and/or hydrophobized, or a membrane; and a blend of catalysts which is deposited on the substrate layer to form a catalyst layer, and includes ORR catalyst (e.g., a platinum group metal), OER catalyst (e.g., nickel-based particles), and possibly binders such as ionomers, PTFE or other polymers that are resistant in alkaline environment, but with the catalyst layer and the substrate layer being devoid of elemental carbon.

Abstract: Membrane assemblies for electrochemical devices are provided, along with methods and system for fabricating them. Membrane assemblies comprise anode layer(s) and cathode layer(s), separated by membranous separation layer(s) and all embedded in continuous polymerized ionomer material. In production, during continuous deposition of ionomer material on a substrate (e.g., by electrospinning or electrospraying), consecutive deposition stages of catalyst material and optionally binder material are performed. For example, anode particles, binder material and cathode particles may be deposited (e.g., by electrospraying or electrospinning, respectively) consecutively during the continuous deposition o the ionomer material. Self-refueling power-generating system are provided, which include reversible anion exchange membrane devices with disclosed membrane assemblies.

Abstract: Membrane assemblies and separation layer(s) for electrochemical devices such as fuel cells and/or electrolyzers are provided, as well as their production methods. The separation layer(s) include surface-charged particles such as LDH particles to strengthen the membranes, enhance their ionic conductivity and prevent or reduce membrane dehydration and/or chemical degradation. In various configurations a single or few, relatively thick separation layer(s) with surface-charged particles may be used, while in other configurations alternating layers of ionomeric material and layers with surface-charged particles may be used, optimizing ionic conductivity with mechanical strength. Thin protective layers with solids content up to 100% may be set adjacent to the electrodes, and the orientation of the surface-charged particles may be set to enhance the ion conductivity of the respective layer.

Abstract: Membrane electrode assemblies (MEA) and electrochemical devices such as fuel cells, electrolyzers and reversible devices are provided. The MEA comprises gas diffusion electrodes (GDEs) comprising respective gas diffusion layers (GDLs) coated with respective catalyst layers, and a thin membrane coated on either or both catalyst layers and having a total thickness of at most 30 microns. The GDEs are joined together to form the MEA with the thin membrane located between the catalyst layers, and the MEA is sealed and stacked to be operable in the electrochemical devices. Advantageously, using the GDEs to deposit the membrane enable forming very thin and efficient membranes.

Abstract: A method of making an alkaline membrane fuel cell assembly is disclosed. The method may include: depositing a first catalyst layer on a first gas diffusion layer to form a first gas diffusion electrode; depositing a second catalyst layer one a second gas diffusion layer to form a second gas diffusion electrode; depositing a thin membrane on at least one of: the first catalyst layer and the second catalyst layer; joining together the first and second gas diffusion electrodes to form the alkaline fuel cell assembly such that the thin membrane is located between the first and second catalyst layers; and sealing the first and second gas diffusion layers, the first and second catalyst layers and the thin membrane from all sides.

Abstract: Some aspects of the invention may be directed to a catalyst layer for anodes of Alkaline Exchange Membrane Fuel Cells (AEMFC). Such catalyst layer may include catalyst nanoparticles and an ionomer. Each catalyst nanoparticle may include one or more nanoparticles of catalytically active metal supported on at least one nanoparticle of crystalline RuO2. The diameter of the at least one nanoparticle of the crystalline RuO2 may be about order of magnitude larger than the diameter of the one or more nanoparticles of catalytically active metal.

Abstract: A method of making an alkaline membrane fuel cell assembly is disclosed. The method may include: depositing a first catalyst layer on a first gas diffusion layer to form a first gas diffusion electrode; depositing a second catalyst layer one a second gas diffusion layer to form a second gas diffusion electrode; depositing a thin membrane on at least one of: the first catalyst layer and the second catalyst layer; joining together the first and second gas diffusion electrodes to form the alkaline fuel cell assembly such that the thin membrane is located between the first and second catalyst layers; and sealing the first and second gas diffusion layers, the first and second catalyst layers and the thin membrane from all sides.

Abstract: Some aspects of the invention may be directed to a catalyst layer for anodes of Alkaline Exchange Membrane Fuel Cells (AEMFC). Such catalyst layer may include catalyst nanoparticles and an ionomer. Each catalyst nanoparticle may include one or more nanoparticles of catalytically active metal supported on at least one nanoparticle of crystalline RuO2. The diameter of the at least one nanoparticle of the crystalline RuO2 may be about order of magnitude larger than the diameter of the one or more nanoparticles of catalytically active metal.