Abstract: Disclosed are a fuel cell system and a control method thereof. The fuel cell system comprises: a main fuel cell stack (6) that an anode (2) and a cathode (4) are arranged in a state that an electrolyte membrane is interposed therebetween; a fuel supplying unit connected with the anode of the main fuel cell stack (6) by a fuel supplying line (16) for supplying hydrogen-including fuel to the anode; an air supplying unit (10) connected to the cathode of the main fuel cell (6) stack by an air supplying line (20) for supplying oxygen-including air to the cathode (4); and a sub fuel cell stack (14) for using hydrogen generated at the anode (2) during reaction as fuel. According to this, energy efficiency of a fuel cell can be increased and danger due to exhaustion of hydrogen generated at the fuel cell stack (6) can be decreased.

Abstract: A fuel cell having a temperature-humidity controller comprising a fuel supply unit for supplying a certain rate of fuel, a stack unit for generating electricity and heat according to an electrochemical reaction between the fuel supplied from the fuel supply unit and oxygen, a heat exchanger for dividing a by-product generated from the stack unit into gas and liquid to be re-circulated, and a temperature-humidity controller for controlling temperature and humidity of indoor areas by introducing the gas divided in the heat exchanger into the indoor areas.

Abstract: A method for purging a fuel cell system comprises detecting a signal for stopping an operation of a fuel cell system, cutting off an electricity output of the fuel cell system, driving a steam generator of a fuel supply unit of the fuel cell system for a certain time and thereby generating steam, certifying whether a purging operation of the fuel cell system has been completed or not, and stopping the fuel cell system, in which the fuel cell system is purged by using steam generated by the steam generator. Since an additional container for storing nitrogen is not required, a fabrication cost is reduced. Also, inconvenience caused by periodically containing nitrogen in the container is solved. Furthermore, when the fuel cell system is used at home, an additional space for installing the nitrogen container is not required and the fuel cell system can be easily installed.

Abstract: A fuel cell system comprises: a stack unit having a cathode and an anode and generating electricity by an electrochemical reaction between hydrogen and oxygen; a fuel supply unit for supplying hydrogen to the anode of the stack unit; an air supply unit for supplying air to the cathode of the stack unit; and a gas-liquid separator for removing moisture included in off-gas supplied to a burner of the fuel supply unit from the stack unit. Moisture included in the off-gas is removed by the gas-liquid separator and thus combustion inside the burner is actively performed. As the result, steam is stably supplied to the steam reformer and thus a reforming reaction is smoothly performed, thereby enhancing an entire function of the fuel cell system.

Abstract: A fuel cell system comprising: a fuel cell stack (6) including an anode (2), a cathode (4), and an electrolyte membrane disposed therebetween; a fuel supplying unit connected with the anode of the fuel cell stack (6) by a fuel supplying line (14) for supplying hydrogen-including fuel to the anode (2); an air supplying unit (10) connected with the cathode of the fuel cell stack by an air supplying line (48) for supplying oxygen-including air to the cathode of the fuel cell stack; and a heating unit (12) for heating fuel supplied to the fuel cell stack into a proper temperature. According to this, a power source for driving the heating unit (12) is not required thus to enhance a performance of a fuel cell.

Abstract: In a bipolar plate of a fuel cell including a plate having a certain area and thickness; inflow and outflow buffer grooves respectively formed at both sides of the plate so as to have a certain area and depth; plural channels for connecting the inflow buffer groove and the outflow buffer groove; plural buffer protrusions formed in the inflow and outflow buffer grooves so as to have a certain height; an inflow path formed on the plate so as to be connected to the inflow buffer groove; and an outflow path formed on the plate so as to be connected to the outflow buffer groove, it is possible to uniformize flux distribution and reduce flow resistance of fuel and air respectively flowing into a fuel electrode and an air electrode of a fuel cell.

Abstract: Disclosed is a fuel cell system comprising: a fuel cell stack including an anode, a cathode, and an electrolyte membrane disposed therebetween; a fuel tank for supplying hydrogen-including fuel to the anode of the fuel cell stack; and an oxidant supplying unit for adding ozone to oxygen-including air and thereby supplying to the cathode of the fuel cell stack. According to this, ozone is supplied to the cathode of the fuel cell stack thus to accelerate a reaction speed in the fuel cell stack and thereby to obtain a relatively high current density.

Abstract: Disclosed is a fuel cell system comprising: a fuel tank connected to a anode of a fuel cell stack for supplying hydrogen-including fuel to the anode; an air supplying unit connected to a cathode of the fuel cell stack for supplying oxygen-including air to the cathode; a heating unit for heating air and fuel supplied to the fuel cell stack; and a purge unit for returning fuel remaining at each system to the fuel tank when a system driving is stopped. According to this, a temperature of the fuel cell stack can reach a goal temperature within the shortest time by heating fuel at the time of driving a system, and fuel remaining at the fuel cell stack and each system is returned to the fuel tank when the system driving is stopped, thereby increasing a performance of the fuel cell system.

Abstract: In a structure for reducing internal circuit of a fuel cell including adjacently stacked unit cells; a fuel side distributing means for connecting each fuel side inflow path of the unit cells and insulating them; and an air side distributing means for connecting each air side inflow path of the unit cells, electric connection among the stacked plural unit cells by fuel as an electrolyte solution and electric leakage by additional parts can be minimized.

Abstract: In a bipolar plate of a fuel cell and a fabrication method thereof, the bipolar plate of the fuel cell includes a plate; a fluid flowing space formed on both sides of the plate; a fluid guide mesh installed on the fluid flowing space; an inflow path formed on the plate to be connected with the fluid flowing space; and an outflow path formed on the plate to be connected with the fluid flowing space. Also, in the fabrication method, the bipolar plate is fabricated with a certain mold and by a processing method. Accordingly, it is possible to uniformize flux distribution and reduce flow resistance of fuel and air respectively flowing into a fuel electrode and an air electrode of a fuel cell. In addition, reaction area with a M.E.A and diffusion zone can be increased, and fabrication can be simplified and facilitated.

Abstract: In a MEA (membrane electrode assembly) of a fuel cell including an electrolyte membrane as an ion transfer medium arranged between a bipolar plate having a fuel side open groove in which fuel flows and a bipolar plate having an air side open groove in which air flows so as to form a fuel path with the fuel side open groove and form an air path with the air side open groove; and a catalyst electrode inserted into the fuel side open groove so as to be separated from the electrolyte membrane in order to form a fuel path with both sides thereof and induce electrochemical oxidation with the fuel, by activating action occurred on the fuel electrode in which fuel is supplied and the air electrode in which air is supplied, current generating efficiency can be improved.