The invention provides a gas diffusion layer for a fuel cell on which a microporous layer is disposed, which can have lower contact resistance with electrode catalyst layers and improved gas diffusion performance. The gas diffusion layer for a fuel cell of the disclosure has a conductive porous substrate layer and a microporous layer laminated in that order, wherein the microporous layer comprises carbon particles and a water-repellent resin, and has an impregnating portion that impregnates the conductive porous substrate layer and a non-impregnating portion that does not impregnate the conductive porous substrate layer, the thickness of the non-impregnating portion is greater than 0.0 μm and 20.0 μm or smaller, and the thickness of the impregnating portion is 29% or lower with respect to the total thickness of the microporous layer.

Redox flow devices are described including a positive electrode current collector, a negative electrode current collector, and an ion-permeable membrane separating said positive and negative current collectors, positioned and arranged to define a positive electroactive zone and a negative electroactive zone; wherein at least one of said positive and negative electroactive zone comprises a flowable semi-solid composition comprising ion storage compound particles capable of taking up or releasing said ions during operation of the cell, and wherein the ion storage compound particles have a polydisperse size distribution in which the finest particles present in at least 5 vol % of the total volume, is at least a factor of 5 smaller than the largest particles present in at least 5 vol % of the total volume.

Redox flow devices are described including a positive electrode current collector, a negative electrode current collector, and an ion-permeable membrane separating said positive and negative current collectors, positioned and arranged to define a positive electroactive zone and a negative electroactive zone; wherein at least one of said positive and negative electroactive zone comprises a flowable semi-solid composition comprising ion storage compound particles capable of taking up or releasing said ions during operation of the cell, and wherein the ion storage compound particles have a polydisperse size distribution in which the finest particles present in at least 5 vol % of the total volume, is at least a factor of 5 smaller than the largest particles present in at least 5 vol % of the total volume.

A close-end fuel cell and an anode bipolar plate thereof are provided. The anode bipolar plate includes an airtight conductive frame and a conductive porous substrate disposed within the airtight conductive frame. In the airtight conductive frame, an edge of a first side has a fuel inlet, and an edge of a second side has a fuel outlet. The conductive porous substrate has at least one flow channel, where a first end of the flow channel communicates with the fuel inlet, a second end of the flow channel communicates with the fuel outlet. The flow channel is provided with a blocking part near the fuel inlet to divide the flow channel into two areas.

A close-end fuel cell and an anode bipolar plate thereof are provided. The anode bipolar plate includes an airtight conductive frame and a conductive porous substrate disposed within the airtight conductive frame. In the airtight conductive frame, an edge of a first side has a fuel inlet, and an edge of a second side has a fuel outlet. The conductive porous substrate has at least one flow channel, where a first end of the flow channel communicates with the fuel inlet, a second end of the flow channel communicates with the fuel outlet. The flow channel is provided with a blocking part near the fuel inlet to divide the flow channel into two areas.

The invention is directed to a barrier layer for corrosion protection in electrochemical devices, e.g. carbon based gas diffusion layers (GDLs) in electrochemical devices, comprising electrically conductive ceramic material and a non-ionomeric polymer binder. The electrically conductive ceramic material has an electrical conductivity of >0.1 S/cm, preferably >1 S/cm in air atmosphere (as detected by the powder method) and is selected from the group of precious metal and/or base metal containing oxides, carbides, nitrides, borides and mixtures and combinations thereof. Membrane-electrode assemblies (MEAs), catalyst-coated membranes (CCMs), gas diffusion electrodes (GDEs) and gas diffusion layers (GDLs) comprising the barrier layer of the invention show improved corrosion resistance, preferably against carbon corrosion; particularly in start-up/shut-down cycles and fuel starvation situations of PEM fuel cells.

The invention is directed to a barrier layer for corrosion protection in electrochemical devices, e.g. carbon based gas diffusion layers (GDLs) in electrochemical devices, comprising electrically conductive ceramic material and a non-ionomeric polymer binder. The electrically conductive ceramic material has an electrical conductivity of >0.1 S/cm, preferably >1 S/cm in air atmosphere (as detected by the powder method) and is selected from the group of precious metal and/or base metal containing oxides, carbides, nitrides, borides and mixtures and combinations thereof. Membrane-electrode assemblies (MEAs), catalyst-coated membranes (CCMs), gas diffusion electrodes (GDEs) and gas diffusion layers (GDLs) comprising the barrier layer of the invention show improved corrosion resistance, preferably against carbon corrosion; particularly in start-up/shut-down cycles and fuel starvation situations of PEM fuel cells.

The present invention provides a gas diffusion electrode including a microporous layer, characterized in that the microporous layer includes at least a first microporous layer and a second microporous layer, wherein the first microporous layer contains a first hydrophobic polymer and is located on the outermost surface on one side of the microporous layer; wherein the second microporous layer contains a second hydrophobic polymer and is located on the outermost surface of the microporous layer on the side opposite to the first microporous layer, and is located on an outermost surface of the gas diffusion electrode; and wherein the first hydrophobic polymer is a resin having a melting point lower than the melting point of the second hydrophobic polymer. The present invention provides a gas diffusion electrode for a fuel cell, in which both high performance and durability are achieved.

A method for the preparation of a gas diffusion layer, containing the steps of: a) preparing a carrier-binder paste comprising a solvent, a fluorinated binder and conductive carrier articles; b) preparing an adhesive composition comprising a solvent, a fluorinated binder and essentially no or equal to or less than 15 wt. % of conductive carrier particles, based on the total weight of fluorinated binder and any conductive carrier particles; and c) combining a layer of supporting material, a layer of the adhesive composition and a layer of the carrier-binder paste, wherein the layer of the adhesive composition is applied between the layer of supporting material and the layer of the carrier-binder paste, and pressing the combination of supporting material, adhesive composition and carrier-binder paste at a pressure of at least 15 kilopascal and/or heating the combination of supporting material, adhesive composition and carrier-binder paste at a temperature of at least 300° C., and a gas diffusion layer so prepared.

The present invention relates to a gas diffusion layer including a porous carbonaceous film layer for a fuel cell, in which the average pore diameter of the porous carbonaceous film layer is 0.1 μm to 100 μm, a membrane-electrode assembly including the gas diffusion layer, and a fuel cell including the membrane-electrode assembly.