Abstract: A fuel cell system including a fuel cell stack having a plurality of unit cells is provided. A method of driving the fuel cell stack is also provided. The method may include supplying a fuel to a fuel cell stack, supplying an oxidizer to the fuel cell stack, controlling supply of the fuel and the oxidizer to operate the fuel cell stack, calculating a total operation time of the fuel cell, and/or varying a stack activation period in which the oxidizer is blocked to the fuel cell stack according to the total operation time and a stack activation cycle of which the stack activation period is generated.

Abstract: A method of driving a fuel cell system is disclosed. The method of driving the fuel cell system may include supplying water to a reformer by pressing a pump pipe to pressing members to move the pressing members in a first direction, stopping power generation including stopping a supply of fuel and oxidant to the reformer, and discharging water in the reformer by moving the pressing members in a second direction opposite to the first direction while pressing the pump pipe with the pressing members. A fuel cell system is also disclosed. The fuel cell system includes a reformer, a fuel cell stack and a water transferring pump. The water transferring pump includes pressing members and a pump pipe. The pump pipe is in fluid communication with a water transferring pipe.

Abstract: A fuel cell system includes a fuel cell stack, an oxidizer supply unit, a reformer, a fuel tank, and a water tank. The reformer generates a hydrogen-containing reformed gas reformed from hydrocarbon-based fuel and supplies it to the fuel cell stack. The fuel tank supplies the hydrocarbon-based fuel to the reformer. The water tank supplies water to the reformer. The reformer includes a reforming unit configured to have a reforming reaction generated therein, a combustion unit configured to supply heat energy to the reforming unit, and a carbon monoxide reduction unit configured to reduce the concentration of carbon monoxide in a reformed gas discharged from the reforming unit. A combustion gas pipe is connected to the combustion unit. A reformed gas pipe is disposed between the reforming unit and the carbon monoxide reduction unit.

Abstract: In one aspect, a composite cathode active material including at least one large-diameter active material, and at least one small-diameter active material, a cathode including the composite cathode active material and a lithium battery including the cathode is provided.

Abstract: A fuel cell system and a control method thereof are capable of preventing anode flooding due to a temperature difference between a stack and reformate upon starting a fuel cell system. The method of controlling a fuel cell system including steps of detecting a temperature of a fuel cell stack, detecting a temperature of reformate that is generated in a fuel reformer and then is supplied to the fuel cell stack through a heat exchanger, and setting the temperature of the reformate to be lower than the temperature of the fuel cell stack during a starting time of the fuel cell system.

Abstract: A method of driving a fuel cell system is disclosed. The method of driving the fuel cell system may include supplying water to a reformer by pressing a pump pipe to pressing members to move the pressing members in a first direction, stopping power generation including stopping a supply of fuel and oxidant to the reformer, and discharging water in the reformer by moving the pressing members in a second direction opposite to the first direction while pressing the pump pipe with the pressing members. A fuel cell system is also disclosed. The fuel cell system includes a reformer, a fuel cell stack and a water transferring pump. The water transferring pump includes pressing members and a pump pipe. The pump pipe is in fluid communication with a water transferring pipe.

Abstract: A fuel cell system including a fuel cell stack having a plurality of unit cells is provided. A method of driving the fuel cell stack is also provided. The method may include supplying a fuel to a fuel cell stack, supplying an oxidizer to the fuel cell stack, controlling supply of the fuel and the oxidizer to operate the fuel cell stack, calculating a total operation time of the fuel cell, and/or varying a stack activation period in which the oxidizer is blocked to the fuel cell stack according to the total operation time and a stack activation cycle of which the stack activation period is generated.

Abstract: A fuel cell system includes a fuel cell stack, an oxidizer supply unit, a reformer, a fuel tank, and a water tank. The reformer generates a hydrogen-containing reformed gas reformed from hydrocarbon-based fuel and supplies it to the fuel cell stack. The fuel tank supplies the hydrocarbon-based fuel to the reformer. The water tank supplies water to the reformer. The reformer includes a reforming unit configured to have a reforming reaction generated therein, a combustion unit configured to supply heat energy to the reforming unit, and a carbon monoxide reduction unit configured to reduce the concentration of carbon monoxide in a reformed gas discharged from the reforming unit. A combustion gas pipe is connected to the combustion unit. A reformed gas pipe is disposed between the reforming unit and the carbon monoxide reduction unit.

Abstract: The present embodiments relate to a fuel cell system having a cartridge stored with liquid fuel and a method of computing a fuel level remained in the cartridge. A fuel cell system of the present embodiments includes: a fuel cartridge for storing fuel; a fuel cell stack for generating power by means of the electrochemical reaction of fuel and oxygen; a fuel pump for sucking fuel stored in the fuel cartridge; a pressure sensor positioned in a fuel channel between a coupling unit of the fuel cartridge and the fuel pump; and a fuel level computing unit for computing a time point when the fuel in the fuel cartridge is almost exhausted. With the present embodiments, the fuel exhaustion in the cartridge can previously sensed at a low cost so that the damage of MEA in the fuel cell can be prevented and the inconvenience or the unexpected damage to a user can be prevented.

Abstract: A direct oxidation fuel cell is provided. A direct oxidation fuel cell includes one or more electricity generators which have a membrane-electrode assembly and anode and cathode members disposed in close contact with respective sides of the membrane-electrode assembly interposed therebetween to generate electrical energy and water by a reaction of a fuel and oxygen. The cathode member includes a plurality of air vents through which air flows and is exposed to the atmosphere. Diameters of a plurality of the air vents gradually increase in a direction toward an exposed area of the cathode member.

Abstract: A direct oxidation fuel cell is provided. A direct oxidation fuel cell includes one or more electricity generators which have a membrane-electrode assembly and anode and cathode members disposed in close contact with respective sides of the membrane-electrode assembly interposed therebetween in order to generate electrical energy and water by a reaction of a fuel and oxygen. The cathode member includes a plurality of air vents of which diameters gradually increase in a direction from a surface of the cathode member closely contacting the membrane-electrode assembly to a surface thereof contacting the atmosphere. Water discharge lines are formed at the surface contacting the atmosphere to discharge water condensed in the air vents. Absorbing members which have a hydrophilic property for absorbing water are formed at the water discharge lines.

Abstract: A fuel cell system and a control method thereof are capable of preventing anode flooding due to a temperature difference between a stack and reformate upon starting a fuel cell system. The method of controlling a fuel cell system including steps of detecting a temperature of a fuel cell stack, detecting a temperature of reformate that is generated in a fuel reformer and then is supplied to the fuel cell stack through a heat exchanger, and setting the temperature of the reformate to be lower than the temperature of the fuel cell stack during a starting time of the fuel cell system.

Abstract: A fuel supply device for a fuel cell and a fuel cell system using the same that prevent H2O, used in reforming from reaching and collecting in the fuel cell stack. The fuel supply device for a fuel cell includes a fuel reformer adapted to generate reformate via a reforming reaction, a gas-liquid separator coupled to an outlet of the fuel reformer, the gas-liquid separator being adapted to receive the reformate and control a moisture amount included within the reformate, a pipe coupled to an outlet of the gas-liquid separator, the pipe being adapted to pass the reformate and a condensed water removing device coupled with the pipe, the condensed water removing device being adapted to prevent condensed water within the reformate within the pipe from passing to an outside.

Abstract: The present embodiments relate to a fuel cell system having a cartridge stored with liquid fuel and a method of computing a fuel level remained in the cartridge. A fuel cell system of the present embodiments includes: a fuel cartridge for storing fuel; a fuel cell stack for generating power by means of the electrochemical reaction of fuel and oxygen; a fuel pump for sucking fuel stored in the fuel cartridge; a pressure sensor positioned in a fuel channel between a coupling unit of the fuel cartridge and the fuel pump; and a fuel level computing unit for computing a time point when the fuel in the fuel cartridge is almost exhausted. With the present embodiments, the fuel exhaustion in the cartridge can previously sensed at a low cost so that the damage of MEA in the fuel cell can be prevented and the inconvenience or the unexpected damage to a user can be prevented.

Abstract: Disclosed is a methanol fuel cell system that utilizes solid methanol as a fuel. The fuel cell system according to the present invention includes a fuel cell stack for generating electricity through a chemical reaction of oxygen and hydrogen produced from solid methanol, a fuel supply tank containing solid methanol, and a recycle line that directs an effluent of the fuel cell stack back to the fuel supply tank.

Abstract: A fuel supply system and a fuel cell system using the same, in which the concentration of fuel to be supplied to a stack is constantly and accurately controlled only on the basis of measured current in a direct methanol fuel cell system.

Abstract: Disclosed is a fuel feeder housing having a mixing tank and a carbon dioxide remover supporting operation of a fuel cell are formed as a single body. A peripheral module having the fuel feeder housing and a pump are modularized, thereby consulting the compactness and the light weight and enhancing the efficiency of the fuel cell. The fuel feeder housing is coupled to a fuel cartridge storing hydrogen-containing fuel and to a fuel cell that generates electricity through an electrochemical reaction between the fuel and an oxidant. The fuel feeder includes a base member in which a chamber for recycling unreacted fuel discharged from the fuel cell and first and second connecting portions for flowing fluid in and out the chamber therethrough are internally formed as a single body and a gas-liquid separator installed in an opening of the chamber and discharging gas from the chamber.

Abstract: A direct oxidation fuel cell is provided. A direct oxidation fuel cell includes one or more electricity generators which have a membrane-electrode assembly and anode and cathode members disposed in close contact with respective sides of the membrane-electrode assembly interposed therebetween in order to generate electrical energy and water by a reaction of a fuel and oxygen. The cathode member includes a plurality of air vents of which diameters gradually increase in a direction from a surface of the cathode member closely contacting the membrane-electrode assembly to a surface thereof contacting the atmosphere. Water discharge lines are formed at the surface contacting the atmosphere to discharge water condensed in the air vents. Absorbing members which have a hydrophilic property for absorbing water are formed at the water discharge lines.

Abstract: A direct oxidation fuel cell is provided. A direct oxidation fuel cell includes one or more electricity generators which have a membrane-electrode assembly and anode and cathode members disposed in close contact with respective sides of the membrane-electrode assembly interposed therebetween to generate electrical energy and water by a reaction of a fuel and oxygen. The cathode member includes a plurality of air vents through which air flows and is exposed to the atmosphere. Diameters of a plurality of the air vents gradually increase in a direction toward an exposed area of the cathode member.

Abstract: A carbon dioxide remover includes: a channel member which has the shape of a pipe which allows the non-reactive fuel and the carbon dioxide to flow, which is connected to the fuel cell body, and which includes a plurality of vent holes for discharging the carbon dioxide; a filter member which is disposed in the channel member to block the vent holes, which separates the carbon dioxide from the non-reactive fuel, and which passes only the carbon dioxide to the vent holes; and one or more suction members which have porosity to suck the non-reactive fuel, and which are disposed inside the channel member.