Abstract: A fuel cell system includes a fuel supply unit for supplying fuel, an air supply unit for supplying air, a coolant supply unit for supplying coolant, and a stack having an electricity generator in which separators are disposed on both surfaces of a membrane-electrode assembly so as to generate electric energy through an electrochemical reaction between hydrogen and oxygen supplied from the fuel supply unit and the air supply unit. The stack includes a plurality of cooling channels through which a coolant is supplied from the coolant supply unit. The cooling channels include contact-area extension surfaces for increasing the contact area of the coolant in order to provide improved cooling efficiency.

Abstract: A fuel cell system includes a fuel supply unit for supplying fuel, an air supply unit for supplying air, and a stack for allowing hydrogen and oxygen supplied from the fuel supply unit and the air supply unit, respectively, to electrochemically react with each other and generating electrical energy. The stack has a membrane-electrode assembly and separators disposed at both sides of the membrane-electrode assembly. Each of the separators has a fuel passage and an air passage, and the total volume of the air passage is greater than the total volume of the fuel passage.

Abstract: The present invention provides a fuel cell system that includes a stack that has at least one electricity generating unit that generates electricity through a reaction between hydrogen and oxygen, a fuel supplier that provides fuel containing hydrogen to the electricity generating unit, an air supplier that provides air to the electricity generating unit, and an insulating unit that surrounds exposed outer surfaces of the stack.

Abstract: Disclosed is a fuel cell system wherein the flow of fuel and oxygen is optimized thereby improving the thermal efficiency of the entire system. The fuel cell system comprises at least one stack for generating electrical energy by an electrochemical reaction between hydrogen gas and oxygen, a fuel supply portion for supplying fuel to the stack, and an oxygen supply portion for supplying oxygen to the stack. The stack is formed in a stacked configuration with MEAs and separators. The separators are positioned on either surface of the MEAs. The separators have a plurality of ribs proximate to the MEAs which define a plurality of channels wherein the ratio of a width of the channels to the width of the ribs is from about 0.8 to 1.5.

Abstract: A fuel cell system optimizing the ratio of width of a channel to a width of a rib forming a passage for supplying fuel and air, the ratio of width thereof to a height of a channel, and the number of passages, thereby improving the fuel diffusing performance and reducing a pressure drop therein is provided. The fuel cell system includes at least one stack for generating electrical energy by an electrochemical reaction between hydrogen and oxygen, a fuel supply portion for supplying fuel to the stack, and an oxygen supply portion for supplying oxygen to the stack. The stack is formed into a stacked configuration having a plurality of membrane electrode assemblies separated by separators. The separators have ribs which closely contact the adjacent membrane electrode assemblies and form channels through which the oxygen and hydrogen flow. The ratio of the width of a channel to the height of the same is between about 0.6 and about 0.8.

Abstract: A fuel cell system that includes at least one electricity generator that generates electric energy through electrochemical reaction between hydrogen and oxygen, a reformer that generates hydrogen gas by reforming fuel containing hydrogen and supplies the hydrogen gas to the electricity generator, a fuel supply unit which supplies the fuel to the reformer, and an oxygen supply unit which supplies oxygen to the electricity generator and the reformer. The reformer includes a double pipe lines that are arranged concentrically and have independent flow paths through which fuel passes, and catalytic layers that are formed in the flow paths, generate thermal energy through chemical catalytic reaction, and generate hydrogen gas from the fuel.

Abstract: A fuel cell system includes a fuel supply unit for supplying fuel, an air supply unit for supplying air, and a stack for generating electric energy through an electro-chemical reaction between hydrogen supplied from the fuel supply unit and oxygen supplied from the air supply unit. The stack includes a membrane-electrode assembly and separators disposed on both sides of the membrane-electrode assembly. Each of the separators has a pathway for transferring the air or the hydrogen, and a ratio of the width to the depth of the pathway is within a range from 0.7 to 1.3.