Abstract: A membrane electrode assembly for a fuel cell and a fuel cell employing the same. The membrane electrode assembly includes: a cathode; an anode; and a polymer electrolyte membrane that is interposed between the cathode and the anode, and comprises a proton conductive polymer that is doped with acid to a doping level of less than 200 mole %. The membrane electrode assembly for the fuel cell exhibits an improved efficiency of performance when acid is doped in the polymer electrolyte membrane at a doping level of less than 200 mole. In addition, the performance of the fuel cell can be optimized by separately adjusting the amount of acid doped in the cathode and anode. The fuel cell employing the membrane electrode assembly can be operated at a high temperature in a dry environment and exhibits an improved power generating performance.

Abstract: A method for preparing a metal catalyst includes a proton conductive material coating layer formed on the surface of a conductive material. Also, an electrode may be prepared using the metal catalyst. The method for preparing the metal catalyst comprises mixing the conductive catalyst material, the proton conductive material, and a first solvent, casting the mixture onto a supporting layer and drying the mixture to form a conductive catalyst containing film. The method further comprises separating the conductive catalyst containing film from the supporting layer and pulverizing the conductive catalyst containing film to obtain the metal catalyst. The method for preparing the electrode comprises mixing the metal catalyst with a hydrophobic binder and a second solvent, coating the mixture on an electrode support, and drying it.

Abstract: A metallic separator for a fuel cell including 2.2 to 6.0 parts by weight of tungsten based on 100 parts by weight of stainless steel containing molybdenum, and the weight ratio of molybdenum to tungsten (Mo/W) is 0.15 to 1.60. The separator for fuel cells has excellent anti-corrosive properties and contact resistance as low as that of a metal material, and thus, a fuel cell having high efficiency can be manufactured at a reasonable cost using the separator.

Abstract: A method for preparing a metal catalyst includes a proton conductive material coating layer formed on the surface of a conductive material. Also, an electrode may be prepared using the metal catalyst. The method for preparing the metal catalyst comprises mixing the conductive catalyst material, the proton conductive material, and a first solvent, casting the mixture onto a supporting layer and drying the mixture to form a conductive catalyst containing film. The method further comprises separating the conductive catalyst containing film from the supporting layer and pulverizing the conductive catalyst containing film to obtain the metal catalyst. The method for preparing the electrode comprises mixing the metal catalyst with a hydrophobic binder and a second solvent, coating the mixture on an electrode support, and drying it.

Abstract: A method for preparing a metal catalyst includes a proton conductive material coating layer formed on the surface of a conductive material. Also, an electrode may be prepared using the metal catalyst. The method for preparing the metal catalyst comprises mixing the conductive catalyst material, the proton conductive material, and a first solvent, casting the mixture onto a supporting layer and drying the mixture to form a conductive catalyst containing film. The method further comprises separating the conductive catalyst containing film from the supporting layer and pulverizing the conductive catalyst containing film to obtain the metal catalyst. The method for preparing the electrode comprises mixing the metal catalyst with a hydrophobic binder and a second solvent, coating the mixture on an electrode support, and drying it.

Abstract: A method of preparing a metal catalyst including a conductive catalyst material and a coating layer formed of a water repellent material on the surface of the conductive catalyst material includes: obtaining a water repellent material solution by mixing a water repellent material and a first solvent; obtaining a conductive catalyst solution by mixing a conductive catalyst material and a first solvent; mixing the water repellent material solution and the conductive catalyst solution; casting the result onto a supporter, drying the cast result and then separating a metal catalyst in a solid state from the supporter; and pulverizing and sieving the product. Also provided is a method of preparing an electrode including the metal catalyst.

Abstract: A separator for a fuel cell includes a first layer that includes stainless steel and tungsten and a second layer that includes stainless steel and tungsten. The first layer contains more tungsten than the second layer so that the separator has anticorrosion properties specifically tailored to the environment of the anode and the cathode.

Abstract: An electrode, a membrane-electrode assembly including the electrode, a fuel cell including the membrane-electrode assembly, and a method of making the same, the electrode including a gas diffusion layer, a catalyst layer, and a water-repellent material having a concentration gradient, disposed at an interface between the gas diffusion layer and the catalyst layer. The water-repellent material may be disposed in a dot pattern.

Abstract: A proton conductor for a fuel cell, an electrode for a fuel cell that includes the proton conductor, and a fuel cell including the electrode of which the proton conductor includes a phosphoric acid-based material, and a C1-C20 ammonium perfluoroalkylsulfonate dissolved in the phosphoric acid-based material.

Abstract: The present invention provides a separator for a fuel cell that comprises a metal substrate that contains at least one metal element M and a surface layer formed on a surface of the metal substrate and that contains at least one conductive oxide represented by LaMxO3 (wherein x=0 to 1). Also, the present invention provides a method for anti-corrosion treatment of a metallic separator for a fuel cell. The method involves first forming an La layer on a surface of a metal substrate having a desired dimension and a desired flow field formed therein. Next, the metal substrate having the La layer on its surface is heated such that at least one metal component contained in the metal substrate is diffused into the La layer and an La component in the La layer is diffused into the metal substrate to form a mixed layer composed of La and the at least one metal component on the surface of the metal substrate.

Abstract: An electrocatalyst for a fuel cell includes a Pt—Co-based first metal catalyst, a Ce-based second metal catalyst, and a carbon-based catalyst support. A method of preparing the electrocatalyst includes obtaining a mixture of metal oxides from a Pt precursor, a Co precursor, and a Ce precursor; impregnating the mixture of the metal oxides onto a carbon-based catalyst support under hydrogen bubbling; and thermally reducing the resulting product at 200 to 350° C. under a hydrogen atmosphere.

Abstract: Provided are a proton conductor for a fuel cell, the proton conductor including a phosphoric acid-based material; and a C8-C20 perfluoroalkylsulfonic acid salt which is dissolved in the phosphoric acid-based material and has excellent oxygen solubility characteristics, an electrode including the proton conductor, an electrolyte membrane for a fuel cell including the proton conductor, and a fuel cell including the electrode and the electrolyte membrane. When the C8-C20 perfluoroalkylsulfonic acid salt is used in the preparation of the electrode and electrolyte membrane for a fuel cell, oxygen solubility is increased in a phosphoric acid-based material and oxygen concentration is increased in a phosphoric acid-based material of the electrode. Thus, reactivity of oxygen reduction which is performed in a cathode is increased. Increased concentration of oxygen in the electrode increases oxygen permeability in the cathode, and thus the resistance against reactants' transfer is decreased.

Abstract: Disclosed is a cathode electrode having a cathode active material layer stacked on a current collector. The cathode active material layer includes a porous conductive material having a surface coated with sulfur and/or a sulfur-containing organic compound and/or pores filled with sulfur and/or a sulfur-containing organic compound. A lithium secondary battery employing the cathode electrode also is disclosed. The cathode electrode is structurally stable during charging and discharging since the structure of the cathode active material layer can be maintained even at the phase transition of sulfur during charging and discharging.

Abstract: A membrane electrode assembly for a fuel cell and a fuel cell employing the same. The membrane electrode assembly includes: a cathode; an anode; and a polymer electrolyte membrane that is interposed between the cathode and the anode, and comprises a proton conductive polymer that is doped with acid to a doping level of less than 200 mole %. The membrane electrode assembly for the fuel cell exhibits an improved efficiency of performance when acid is doped in the polymer electrolyte membrane at a doping level of less than 200 mole. In addition, the performance of the fuel cell can be optimized by separately adjusting the amount of acid doped in the cathode and anode. The fuel cell employing the membrane electrode assembly can be operated at a high temperature in a dry environment and exhibits an improved power generating performance.

Abstract: A method of preparing a metal catalyst including a conductive catalyst material and a coating layer formed of a water repellent material on the surface of the conductive catalyst material includes: obtaining a water repellent material solution by mixing a water repellent material and a first solvent; obtaining a conductive catalyst solution by mixing a conductive catalyst material and a first solvent; mixing the water repellent material solution and the conductive catalyst solution; casting the result onto a supporter, drying the cast result and then separating a metal catalyst in a solid state from the supporter; and pulverizing and sieving the product. Also provided are a metal catalyst prepared using the method, an electrode including the metal catalyst, a method of preparing the electrode, and a fuel cell employing the electrode.

Abstract: A metallic separator for a fuel cell including 2.2 to 6.0 parts by weight of tungsten based on 100 parts by weight of stainless steel containing molybdenum, and the weight ratio of molybdenum to tungsten (Mo/W) is 0.15 to 1.60. The separator for fuel cells has excellent anti-corrosive properties and contact resistance as low as that of a metal material, and thus, a fuel cell having high efficiency can be manufactured at a reasonable cost using the separator.

Abstract: A supported electrochemical catalyst used to produce a proton exchange membrane fuel cell, the supported anode catalyst including an electrically conductive support and Pt/Ni based alloy nanoparticles. The supported electrochemical catalyst can be synthesized using an improved microwave-irradiated polyol (IMIP) method, and a heat treating method while being subjected to a reduction reaction under an inert environment. The catalyst exhibits an improved carbon monoxide (CO) tolerance and high activity with respect to a hydrogen oxidation reaction. In addition, the manufacturing method for the supported electrochemical catalyst is simple, environmentally friendly, quick, and inexpensive.

Abstract: A method of preparing electrochemical catalyst for proton exchange membrane fuel cells (PEFC), more particularly, a method of preparing a nano-sized, Pt-based bi-component or multi-component electrochemical catalyst for an anode and a cathode of PEFC that enables preparation of an electrochemical catalyst for PEFC, which has high activity, is simply prepared, and has active components uniformly distributed therein.

Abstract: A CO tolerant electrochemical catalyst for proton exchange membrane fuel cells (PEFC) and a method of preparing includes a PtAu-MxOy/C supported electrochemical catalyst for the PEFC. The electrochemical catalyst has high catalytic activity and has uniformly distributed active components. The method is simple, is easily managed, and is environmentally friendly.

Abstract: A separator for a fuel cell includes a first layer that includes stainless steel and tungsten and a second layer that includes stainless steel and tungsten. The first layer contains more tungsten than the second layer so that the separator has anticorrosion properties specifically tailored to the environment of the anode and the cathode.