The present invention relates to a gas diffusion layer for a fuel cell, made of a carbon substrate grafted with at least one aromatic group having formula (II):

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wherein: the asterisk * designates a carbon atom with no hydrogen and no R.sup.i group, with i=1 to 5, and covalently bonded to the carbon substrate; at least two of the R.sup.1, R.sup.2, R.sup.3, R.sup.4, and R.sup.5 groups are different from a hydrogen atom; at least two of the R.sup.1, R.sup.2, R.sup.3, R.sup.4, and R.sup.5 groups are hydrophobic groups or hydrophilic groups or a hydrophobic group and a hydrophilic group.

A single cell C includes a membrane electrode assembly M in which an electrolyte membrane 1 is interposed between a pair of electrode layers 2, 3, and a pair of separators 4 that form gas channels C between the pair of separators 4 and the membrane electrode assembly M, wherein the electrode layers 2, 3 include first gas diffusion layers 2B, 3B of a porous material disposed at the side facing the electrolyte membrane 1 and second gas diffusion layers 2C, 3C that are composed of a metal porous body having arrayed many holes K, and a part of the first gas diffusion layers 2B, 3B penetrates the holes K of the second gas diffusion layers 2C, 3C to form protrusions T. Accordingly, the surface of the electrode layers 2, 3 has a fine uneven structure. As a result, an improvement in liquid water discharging function and an improvement in power generating function were achieved at the same time.

A membrane electrode assembly and a method of manufacturing an electricity generating assembly include a pair of gas diffusion layers disposed on both surfaces of the membrane electrode assembly. Coupling agents are applied on surfaces of the gas diffusion layers, modifying surfaces of the gas diffusion layers. A coupling agent-friendly adhesive is applied to the surfaces of the gas diffusion layers to which the coupling agents are applied, forming adhesion layers on surfaces of the gas diffusion layers. The gas diffusion layers are stacked on the surfaces of the membrane electrode assembly, causing the adhesion layers to come into contact with the first and second surfaces of the membrane electrode assembly.

[Problem to be Solved] To provide a vanadium active material solution which has a vanadium active material concentration of 2.5 M or more in a sulfuric acid solution including a dispersoid (suspensible material), can stably maintain high energy density based on the concentration, and can respond also to fast charge and discharge, and to provide a vanadium redox battery using the active material solution.

[Solution] The above problem is solved by a vanadium active material solution comprising a vanadium compound, which is an active material, as a solute and a dispersoid, wherein the total concentration of vanadium is 2.5 M or more. Here, in a negative electrolyte, the vanadium compound comprises one or both of bivalent and trivalent vanadium. In a positive electrolyte, the vanadium compound comprises one or both of quadrivalent and pentavalent vanadium. In an active material solution, the vanadium compound comprises one or both of trivalent and quadrivalent vanadium. The average diameter of the dispersoid is in the range of 1 nm or more and 100 μm or less.

The present specification relates to a polymer electrolyte membrane, an electrochemical battery including the polymer electrolyte membrane, an electrochemical battery module including the electrochemical battery, a flow battery including the polymer electrolyte membrane, a method for manufacturing a polymer electrolyte membrane, and an electrolyte solution for a flow battery.

The invention relates to a proton flow reactor for use in storing and releasing energy. In use, a slurry of storage particles in a liquid electrolyte may pass through a first half cell of the proton flow reactor. When the proton flow reactor is in charge mode, protons are bonded or otherwise attracted to the storage particles to form charged storage particles charged with hydrogen, which can hen be stored and/or transported for later use. When the proton flow reactor is in discharge mode, protons are removed from the charged storage particles to fuel an electrochemical reaction, thereby generating electricity. Alternatively, the proton flow reactor in discharge mode can be configured to generate hydrogen gas directly from the in-flowing charged carbon particles.

Disclosed herein is a porous electrode substrate in which carbon fibers are dispersed in the structure thereof have a fiber diameter of 3-15 micron and a fiber length of 2-30 mm, and are bound to one another by carbonized resin such that, when a pore distribution in the porous electrode is determined with a mercury intrusion porosimeter, such that a pore distribution curve is plotted on a graph having a common logarithmic scale on the horizontal axis, and a 1-100 micron pore diameter range of the pore distribution curve includes 80 or more measurement points at equal intervals along the common logarithmic scale, the pore distribution has a skewness S of -2.0<S<-0.8 and a kurtosis K of 3.5<K<10 in the 1-100 micron pore diameter range.

The purpose of the present invention is to provide: a method for producing a gas diffusion electrode base which enables the achievement of a gas diffusion electrode base that has a microporous layer with small surface roughness and is not susceptible to damaging an electrolyte membrane; and a gas diffusion electrode base that has a microporous layer with small surface roughness and is not susceptible to damaging an electrolyte membrane. For the purpose of achieving the above-described purpose, the present invention has the configuration described below. Namely, a specific gas diffusion electrode base which has a carbon sheet and a microporous layer, and wherein the carbon sheet is porous and the DBP oil absorption of a carbon powder contained in the microporous layer is 70-155 ml/100 g.

This disclosure provides a manufacturing method for manufacturing a fuel cell separator. The manufacturing method includes: providing a material sheet including a fiber sheet, carbon particles, and a resin, the carbon particles and the resin being applied to the fiber sheet; and pressing the material sheet into a recess-projection shape by which a gas circulation passage is to be formed, and forming a top portion and a shift portion. In the pressing of the material sheet, the material sheet is pressed such that a draft of the top portion is higher than a draft of the shift portion.

This disclosure provides a manufacturing method for manufacturing a fuel cell separator. The manufacturing method includes: providing a material sheet including a fiber sheet, carbon particles, and a resin, the carbon particles and the resin being applied to the fiber sheet; and pressing the material sheet into a recess-projection shape by which a gas circulation passage is to be formed, and forming a top portion and a shift portion. In the pressing of the material sheet, the material sheet is pressed such that a draft of the top portion is higher than a draft of the shift portion.