Abstract: A membrane electrode assembly for a fuel cell provides a current collector adjacent to an electrode catalyst layer. Since electrons passing between the current collector and the electrode catalyst layer do not pass through a diffusion layer or a supporting layer, the diffusion layer or supporting layer may be non-conductive. Thus, various materials that are hydrophilic, hydrophobic, porous, hydrous, or the like can be used for the diffusion layer and the supporting layer, thereby improving the performance of the fuel cell. In addition, manufacturing costs of the membrane electrode assembly can be decreased since the membrane electrode assembly can be manufactured quickly with low energy.

Abstract: A fuel cell includes a cathode, an anode, an electrolyte membrane interposed between the cathode and the anode, and a porous layer containing a moisture retentive material. The anode includes an anode catalyst layer adjacent to the electrolyte membrane and an anode diffusion layer adjacent to the anode catalyst layer, and the porous layer is disposed between the anode catalyst layer and the electrolyte membrane. The performance of the fuel cell can be stably maintained even when a fuel supply is temporarily interrupted due to a malfunction of a pump or clogging of a fuel channel.

Abstract: The present invention relates to a modified inorganic material with excellent cation exchange capacity. In addition, the invention relates to a method of preparing the modified inorganic material, a composite electrolyte membrane comprising the modified inorganic material powder that has excellent methanol-repelling ability, and a fuel cell comprising the composite electrolyte membrane. The modified inorganic material includes an inorganic material, and a cation exchanger bonded to the inorganic material.

Abstract: A fuel cell system is provided with a first separation layer and a buffer solution layer disposed between a liquid-phase fuel storage layer and an anode of a membrane electrode assembly. A vapor-phase fuel is transferred to the buffer solution layer through the first separation layer, condensed, and diluted to produce a liquid-phase fuel with a low concentration in the buffer solution layer, and the low concentration liquid-phase fuel is supplied to the membrane electrode assembly. A second separation layer may be interposed between the first separation layer and the fuel storage layer. Fuel is supplied by a passive supplying method so that the system can be small with a high efficiency and unnecessary power consumption can be prevented. The fuel cell system can be operated regardless of orientation.

Abstract: An ion-conductive composite membrane and a method of manufacturing the same, the membrane including phosphate platelets, a silicon compound, and a Keggin-type oxometalate and/or Keggin-type heteropoly acid, wherein the phosphate platelets are three-dimensionally connected to each other via the silicon compound. An electrolyte membrane having an ion-conductive inorganic membrane or an ion-conductive organic/inorganic composite membrane effectively prevents crossover of liquid fuel without the reduction of ion conductivity in a liquid fuel cell, thereby allowing for the production of fuel cells having excellent performance.

Abstract: An ion-conductive composite membrane and a method of manufacturing the same, the membrane including phosphate platelets, a silicon compound, and a Keggin-type oxometalate and/or Keggin-type heteropoly acid, wherein the phosphate platelets are three-dimensionally connected to each other via the silicon compound. An electrolyte membrane having an ion-conductive inorganic membrane or an ion-conductive organic/inorganic composite membrane effectively prevents crossover of liquid fuel without the reduction of ion conductivity in a liquid fuel cell, thereby allowing for the production of fuel cells having excellent performance.

Abstract: An ion-conductive composite membrane and a method of manufacturing the same, the membrane including phosphate platelets, a silicon compound, and a Keggin-type oxometalate and/or Keggin-type heteropoly acid, wherein the phosphate platelets are three-dimensionally connected to each other via the silicon compound. An electrolyte membrane having an ion-conductive inorganic membrane or an ion-conductive organic/inorganic composite membrane effectively prevents crossover of liquid fuel without the reduction of ion conductivity in a liquid fuel cell, thereby allowing for the production of fuel cells having excellent performance.

Abstract: A multiblock copolymer includes a polysulfone repeating unit, a sulfonated polysulfone repeating unit, a polydialkylsiloxane repeating unit and an ethylenic unsaturated group at a terminal of the multiblock copolymer. Also provided are a method of preparing the multiblock copolymer, a polymer electrolyte membrane prepared from the multiblock copolymer, a method of preparing the polymer electrolyte membrane, and a fuel cell including the polymer electrolyte membrane. The polymer electrolyte membrane that has a high ionic conductivity and good mechanical properties and minimizes crossover of methanol can be manufactured at low cost. In addition, the structure of the multiblock copolymer can be varied to increase selectivity to a solvent used in a polymer electrolyte membrane.

Abstract: A supported catalyst includes a carbonaceous catalyst support and first metal-second metal alloy catalyst particles adsorbed on the surface of the carbonaceous catalyst support, wherein the difference between a D10 value and a D90 value is in the range of 0.1 to 10 nm, wherein the D10 value is a mean diameter of a randomly selected 10 wt % of the first metal-second metal alloy catalyst particles and the D90 value is a mean diameter of a randomly selected 90 wt % of the alloy catalyst particles. The supported catalyst has excellent membrane efficiency in electrodes for fuel cells due to uniform alloy composition of a catalyst particle and supported catalysts that do not agglomerate.

Abstract: A proton conductive copolymer includes styrene repeating units that have proton conductive functional groups and dimethylsiloxane repeating units. A polymer electrolyte membrane includes the proton conductive copolymer and a fuel cell uses the polymer electrolyte membrane. The proton conductive copolymer has excellent chemical and mechanical properties, excellent ability to form membrane with dimethylsiloxane repeating units, and superior ion conductivity with styrene repeating units that have proton conductive functional groups. Polymer electrolyte membranes that have properties appropriate for the fuel cell electrolyte membrane can be obtained using the proton conductive copolymer. Fuel cells that have improved efficiencies can be obtained using the polymer electrolyte membrane.

Abstract: A proton conducting titanate includes titanate and a sulfonic acid group-containing moiety having proton conductivity introduced into the surface of the titanate, in which the sulfonic acid group-containing moiety is directly bound to the titanate via an ether bond (—O). A polymer nano-composite membrane includes the proton conducting titanate, and a fuel cell includes the polymer nano-composite membrane. The proton conducting titanate is provided with a sulfonic acid functional group having proton conductivity, which increases the proton conductivity of the polymer nano-composite membrane. The polymer nano-composite membrane includes the proton conducting titanate, and thus can have a controllable degree of swelling in a methanol solution, and the transmittance of the polymer nano-composite membrane can be reduced. The polymer nano-composite membrane can be used as a proton conducting membrane in fuel cells to improve the thermal stability, energy density, and fuel efficiency of the fuel cells.

Abstract: A multiblock copolymer includes a polysulfone repeating unit, a sulfonated polysulfone repeating unit and an ethylenic unsaturated group at a terminal of the multiblock copolymer. Also provided are a method of preparing the multiblock copolymer, a polymer electrolyte membrane prepared from the multiblock copolymer, a method of preparing the polymer electrolyte membrane, and a fuel cell including the polymer electrolyte membrane. The polymer electrolyte membrane that has a high ionic conductivity and good mechanical properties and minimizes crossover of methanol can be manufactured at low cost. In addition, the structure of the multiblock copolymer can be varied to increase selectivity to a solvent used in a polymer electrolyte membrane.

Abstract: The invention provides and a highly-dispersed supported catalyst that has a reduced average particle size of catalytic metal particles and is also supported by a porous support material. A method of preparing a supported catalyst that can reduce the average particle size of catalytic metal particles supported by a support material includes first mixing a charged support material with a solution containing a polymer electrolyte having a charge opposite to that of the support material to adsorb the polymer electrolyte on the support material. Next, the support material having the polymer electrolyte adsorbed thereon is mixed with a solution containing a catalytic metal precursor ion having a charge opposite to that of the polymer electrolyte to adsorb the catalytic metal precursor ion on the support material having the polymer electrolyte adsorbed on it.

Abstract: A polymer electrolyte and a fuel cell employing the polymer electrolyte are provided. The polymer electrolyte includes: an ionic conductive polymer membrane; a porous support having nano-sized pores; and inorganic conductive nano-particles including an ionic conductive material impregnated into the porous support, wherein the inorganic conductive nano-particles are impregnated into microchannels formed by aggregation of polar portions of the ionic conductive polymer membrane, and/or between polymer backbones of the ionic conductive polymer membrane.

Abstract: A polymer electrolyte and a fuel cell employing the polymer electrolyte are provided. The polymer electrolyte includes: an ionic conductive polymer membrane; a porous support having nano-sized pores; and inorganic conductive nano-particles including an ionic conductive material impregnated into the porous support, wherein the inorganic conductive nano-particles are impregnated into microchannels formed by aggregation of polar portions of the ionic conductive polymer membrane, and/or between polymer backbones of the ionic conductive polymer membrane.

Abstract: A liquid-gas separator for a direct liquid feed fuel cell includes a tube having an opening portion at a sidewall thereof; liquid extracting members that selectively transmit the liquid in the tube and located at both ends of the tube; a gas extracting membrane that selectively transmits the gas and covers the opening portion; an inlet that guides the liquid and the gas into the tube; chambers that surround an outer side of the liquid extracting member; and outlets that guide the liquid in the chambers to the outside by being connected to the chamber.

Abstract: A polymer electrolyte forming composition includes a trialkoxysilane containing an epoxy group, polyethyleneimine, and at least one of heteropolyacid and trifluoromethanesulfoneimide.

Abstract: A composition containing a proton-conductive copolymer, a polymer electrolyte membrane containing the composition; a method of producing the membrane; and a fuel cell employing the membrane. The composition includes: a proton-conductive copolymer comprising a first styrene repeating unit, a second styrene repeating unit, and a dimethylsiloxane repeating unit; and a cross-linked polymer obtained from a cross-linking reaction between a siloxane oligomer having an unsaturated bond and a cross-linking agent. The cross-linked polymer has the same properties as the dimethylsiloxane repeating unit of the proton-conductive copolymer.

Abstract: A fuel amount control system of a fuel cell includes a fuel storage unit that stores the fuel to be supplied to the anode, a diluent storage unit that stores a diluent generated as a result of the chemical reaction in the cathode, a fuel mixing unit that mixes the fuel supplied from the fuel storage unit and the diluent supplied from the diluent storage unit to supply a fuel mixture solution to the anode, a sensor located inside the fuel mixing unit, which has a various volume that depends on the concentration of the fuel in the fuel mixture solution and outputs an electrical signal according to a volume variation, and a control unit that receives the electrical signal output from the sensor and outputs electrical signals to open and close the fuel storage unit and the diluent storage unit such that the fuel mixture solution having an appropriate concentration is supplied from the fuel mixing unit to the fuel cell stack.

Abstract: Disclosed herein is a slurry-type coating solution for cation-conducting polymer composite membranes that is capable of producing cation-conducting polymer composite membranes with high ionic conductivity as well as low methanol permeability and low ohmic resistance when used in direct-methanol fuel cells, via pluralization of solvents and use of specific additives. The coating slurry comprises about 1 to about 10 parts by weight of a sulfonated clay, about 100 parts by weight of a cation exchange group-containing polymer, and a co-solvent consisting of a high-boiling point solvent with a boiling point of about 180 to about 250° C. and a low-boiling point solvent with a boiling point of about 100 to about 180° C.