This invention relates to an electrode structure including a porous electrode that simultaneously performs the functions both of a bipolar plate and of a felt electrode and has a pattern layer or a mesh layer serving as a flow path on the surface thereof, a method of manufacturing the same, and a redox flow battery stack configuration for decreasing shunt current.

Disclosed is a lithium secondary battery including: a positive electrode current collector comprising a positive electrode material mixture; a negative electrode current collector comprising of a negative electrode material mixture and laminated on the positive electrode current collector; a separator disposed between the positive electrode current collector and the negative electrode current collector; and a composite conductive material coated on the separator which faces the positive electrode current collector.

The invention includes a method of making a catalytic electrode for a metal-air cell in which a carbon-catalyst composite is produced by heating a manganese compound in the presence of a particulate carbon material to form manganese oxide catalyst on the surfaces of the particulate carbon, and then adding virgin particulate carbon material to the carbon-catalyst composite to produce a catalytic mixture that is formed into a catalytic layer. A current collector and an air diffusion layer are added to the catalytic layer to produce the catalytic electrode. The catalytic electrode can be combined with a separator and a negative electrode in a cell housing including an air entry port through which air from outside the container can reach the catalytic electrode.

Improved membrane electrode assemblies, cation-associating components thereof, and methods of making and treating the same are provided. Membrane electrode assemblies may include an ionomer having a first pKa value, and a water-insoluble net polymer having a weakly-acidic functional group, wherein the weakly-acidic functional group has a second pKa value greater than the first pKa value.

Described herein are direct liquid fuel cells with an alkaline anodic fuel stream including a solution of liquid fuel such as alcohols, ethers, glycols or compounds of hydrazine, and an acidic cathode oxidant stream including a solution of a suitable oxidant such as hydrogen peroxide or a gas steam with 1% to 100% O.sub.2. These cells are used as primary stationary and/or mobile power sources and also function in a secondary role as range extenders when coupled with a primary power source.

Provided is a catalyst for fuel cell which has a high catalytic activity and enables maintaining the high catalytic activity. Disclosed is an electrode catalyst for fuel cell comprising a catalyst carrier containing carbon as a main component and a catalytic metal supported on the catalyst carrier, wherein the catalyst has the R′ (D′/G intensity ratio) of 0.6 or less, which is the ratio of D′ band peak intensity (D′ intensity) measured in the vicinity of 1620 cm.sup.−1 relative to G band peak intensity (G intensity) measured in the vicinity of 1580 cm.sup.−1 by Raman spectroscopy, and the volume ratio of a water vapor adsorption amount relative to a nitrogen adsorption amount at a relative pressure of 0.5 in adsorption isotherm is 0.15 or more and 0.30 or less.

In one aspect of the present invention, a fiber mat is provided. The fiber mat includes at least one type of fibers, which includes one or more polymers. The fiber mat may be a single fiber mat which includes one type of fibers, or may be a dual or multi fiber mat which includes multiple types of fibers. The fibers may further include particles of a catalyst. The fiber mat may be used to form an electrode or a membrane. In a further aspect, a fuel cell membrane-electrode-assembly has an anode electrode, a cathode electrode, and a membrane disposed between the anode electrode and the cathode electrode. Each of the anode electrode, the cathode electrode and the membrane may be formed with a fiber mat.

A porous carbon sheet contains a carbon fiber and a binding material, wherein layers are obtained in a section spanning from a plane closest to one of the surfaces and having 50% of the mean fluorine intensity to a plane closest to the other surface and having 50% of the mean fluorine intensity by dividing this section evenly into three in an orthogonal direction to the carbon sheet plane; among the layer close to one of the surfaces and the layer close to the other surface, the layer having the larger layer mean fluorine intensity is designated layer X, the layer having the smaller one is designated layer Y, and the layer between the layer X and the layer Y is designated layer Z; and the layer mean fluorine intensities decrease in the order: layer X, layer Y, and layer Z.

An expanded graphite sheet and a battery using the expanded graphite sheet are provided, that can inhibit the expanded graphite sheet from swelling even when the expanded graphite sheet is used for, for example, a positive electrode for an air battery. An expanded graphite sheet includes an expanded graphite and has a surface water contact angle of greater than or equal to 90 degrees and a surface resistivity of less than or equal to 70 mΩ/sq. It is desirable that a polyolefin resin be contained in the expanded graphite sheet in a dispersed state. It is desirable that the polyolefin resin be polypropylene.

An illustrative example method of making a fuel cell component includes mixing a catalyst material with a hydrophobic binder in a solvent to establish a liquid mixture having at least some coagulation of the catalyst material and the hydrophobic binder. The liquid mixture is applied to at least one side of a porous gas diffusion layer. At least some of the solvent of the applied liquid mixture is removed from the porous gas diffusion layer. The catalyst material remaining on the porous gas diffusion layer is dried under pressure.