The presently disclosed subject matter relates to devices, systems, and methods for fabricating a solid polymer electrolyte electrode assembly are provided. One or more electrode for a solid polymer electrolyte electrode assembly includes a porous substrate configured as a liquid/gas diffusion layer and an ionomer-free catalyst coated on the substrate.

A cathode electrode for a gas diffusion electrolytic flow cell that produces a carbon dioxide reduction product by reducing carbon dioxide, wherein the cathode electrode comprises a catalyst layer having a metal complex catalyst, a carbon material and an alkali metal salt, and a gas diffusion layer disposed on the catalyst layer.

A layer system (1) for coating a bipolar plate (2), including at least one cover layer (1a) made of tin oxide, wherein at least one metal oxide of the group comprising tantalum oxide, niobium oxide, titanium oxide, zirconium oxide, and hafnium oxide is homogenously dissolved in the tin oxide, and the electric conductivity of the cover layer (1a) is greater than or equal to 10.sup.2 S/cm. A bipolar plate (2, 2′) is also provided with an anode side and a cathode side, comprising a substrate (2a, 2a′) and such a layer system (1), and to a fuel cell (10) or an electrolyzer comprising such a bipolar plate (2, 2′).

A layer system (1) for coating a bipolar plate (2), including at least one cover layer (1a) made of tin oxide, wherein at least one metal oxide of the group comprising tantalum oxide, niobium oxide, titanium oxide, zirconium oxide, and hafnium oxide is homogenously dissolved in the tin oxide, and the electric conductivity of the cover layer (1a) is greater than or equal to 10.sup.2 S/cm. A bipolar plate (2, 2′) is also provided with an anode side and a cathode side, comprising a substrate (2a, 2a′) and such a layer system (1), and to a fuel cell (10) or an electrolyzer comprising such a bipolar plate (2, 2′).

In this disclosure, a process of recycling acid, base and the salt reagents required in the Li recovery process is introduced. A membrane electrolysis cell which incorporates an oxygen depolarized cathode is implemented to generate the required chemicals onsite. The system can utilize a portion of the salar brine or other lithium-containing brine or solid waste to generate hydrochloric or sulfuric acid, sodium hydroxide and carbonate salts. Simultaneous generation of acid and base allows for taking advantage of both chemicals during the conventional Li recovery from brines and mineral rocks. The desalinated water can also be used for the washing steps on the recovery process or returned into the evaporation ponds. The method also can be used for the direct conversion of lithium salts to the high value LiOH product. The method does not produce any solid effluent which makes it easy-to-adopt for use in existing industrial Li recovery plants.

In this disclosure, a process of recycling acid, base and the salt reagents required in the Li recovery process is introduced. A membrane electrolysis cell which incorporates an oxygen depolarized cathode is implemented to generate the required chemicals onsite. The system can utilize a portion of the salar brine or other lithium-containing brine or solid waste to generate hydrochloric or sulfuric acid, sodium hydroxide and carbonate salts. Simultaneous generation of acid and base allows for taking advantage of both chemicals during the conventional Li recovery from brines and mineral rocks. The desalinated water can also be used for the washing steps on the recovery process or returned into the evaporation ponds. The method also can be used for the direct conversion of lithium salts to the high value LiOH product. The method does not produce any solid effluent which makes it easy-to-adopt for use in existing industrial Li recovery plants.

A coated electrode assembly (CEA) comprising: i) a gas diffusion layer (GDE); and ii) a coating. The GDE comprises a gas diffusion layer (GDL) and a catalyst layer. The catalyst layer is disposed between the coating and the GDL. The catalyst layer comprises a hydrophobic polymer and/or an ionomeric polymer and the coating comprises a hydrophobic polymer and/or an ionomeric polymer. A method for making a CEA is provided. The CEA may have improved performance and stability compared to a membrane electrode assembly (MEA).

A coated electrode assembly (CEA) comprising: i) a gas diffusion layer (GDE); and ii) a coating. The GDE comprises a gas diffusion layer (GDL) and a catalyst layer. The catalyst layer is disposed between the coating and the GDL. The catalyst layer comprises a hydrophobic polymer and/or an ionomeric polymer and the coating comprises a hydrophobic polymer and/or an ionomeric polymer. A method for making a CEA is provided. The CEA may have improved performance and stability compared to a membrane electrode assembly (MEA).

Provided is a water electrolysis cell capable of suppressing a deterioration in performance even when a microporous layer is provided. A water electrolysis cell includes a solid polymer electrolyte membrane, a catalyst layer, a microporous layer, and a gas diffusion layer. The microporous layer includes a carrier made of an oxide containing at least one element selected from Ti, Mn, Co, Mo, Ru, W, Nb, and Ta, and a conductive material supported on the carrier.

Provided is a water electrolysis cell capable of suppressing a deterioration in performance even when a microporous layer is provided. A water electrolysis cell includes a solid polymer electrolyte membrane, a catalyst layer, a microporous layer, and a gas diffusion layer. The microporous layer includes a carrier made of an oxide containing at least one element selected from Ti, Mn, Co, Mo, Ru, W, Nb, and Ta, and a conductive material supported on the carrier.