Abstract: A fuel cell cartridge includes a fuel pouch to store fuel, the fuel pouch including a fuel outlet; a pressing unit to press the fuel pouch; a variable resistor provided near the fuel pouch; a sensor provided on the pressing unit to read a resistance value of the variable resistor; and a contact pad to transmit an output voltage determined by the resistance value outside the fuel cell cartridge.

Abstract: The volume of liquid that remains in a liquid storage is calculated by measuring capacitances between several pairs of metal plates attached to each of several corresponding faces of the liquid storage and by combining liquid volumes corresponding to the capacitance based on the current position of the liquid storage. Such a method of measuring the volume of liquid can be used to measure the amount of fuel that remains in a fuel cell system.

Abstract: Provided are a droplet emitting apparatus and a method of emitting droplets using the same. The apparatus includes a solution tank for containing a solution; a nozzle including an opening through which at least a droplet of the solution is emitted; and a voltage generator including a piezoelectric material for generating a voltage by instantaneous pressure application, wherein the voltage generated by the pressure to the piezoelectric material is applied to the solution in order for the at least a droplet of the solution to be emitted through the nozzle.

Abstract: A fuel cell system including: a fuel cell stack configured to generate electrical energy by a reaction of a fuel and an oxidant; a fuel supply configured to supply the fuel to the fuel cell stack; and an oxidant supply configured to supply the oxidant to the fuel cell stack, wherein the fuel supply includes a mixer including an inflow port, the mixer alternately receiving the fuel and water through the inflow port and being configured to mix the fuel and the water to generate a diluted fuel and supply the diluted fuel to the fuel cell stack.

Abstract: A direct liquid feed fuel cell stack includes a first end plate and a second end plate facing each other, and a plurality of unit cell modules mounted between the first end plate and the second end plate, wherein an electrical circuit that contacts terminals of the unit cell modules is formed on an inner surface of the first end plate.

Abstract: Disclosed herein is a fuel injection apparatus for injecting fuel into a fuel cartridge. The fuel injection apparatus may include, for example, a container for fuel storage, a fuel supply pipe in fluid communication with the container, a first valve installed on the fuel supply pipe, a pump installed on the fuel supply pipe, a pressure gauge installed on the fuel supply pipe, and a bypass pipe fluidly connecting the container with the fuel supply pipe. A second valve may be installed on the bypass pipe. Methods for injecting fuel into a fuel cartridge are also disclosed herein.

Abstract: A target value of each of factors in a fuel cell system is determined based on a correspondence relationship of a change in each of the factors determining reaction conditions of fuel in a fuel cell to a change in an external environment of the fuel cell system, and peripheral devices of the fuel cell affecting the reaction conditions of the fuel in the fuel cell are controlled according to a target value of each of the factors.

Abstract: A direct liquid feed fuel cell system includes fuel cells including an electrolyte membrane, a plurality of cathode electrodes formed on a first surface of the electrolyte membrane, and anode electrodes formed on a second part of the electrolyte membrane; and a high concentration fuel storage unit and a low concentration fuel storage unit which are separated from each other and store a liquid fuel to be supplied to the fuel cell. The liquid fuel in the low concentration fuel storage unit is supplied to the anode electrodes wherein the liquid fuel in the low concentration fuel storage unit is supplied to the anode electrodes when pressure is applied to the low concentration fuel storage unit, such as when the direct liquid feed fuel cell system having the low concentration fuel storage unit is mounted on an electronic device.

Abstract: A fuel cell system for supplying output power of at least one of a fuel cell and a battery to a load selects one of various operation modes of the fuel cell system based on a change of an output state of the fuel cell and controls the supply of the output power of each of the fuel cell and the battery to the load according to the selected operation mode.

Abstract: A hybrid voltage supply apparatus, a method of controlling the same, and an electronic system employing the hybrid voltage supply apparatus as a power supply are provided. The hybrid voltage supply apparatus includes a hybrid voltage supply apparatus including a main power supply, an auxiliary power supply, and a first voltage adjustment unit which operates in any one of a feed-forward driving mode and a feed-back driving mode according to at least one operating parameter of the main power supply, and adjusts an output voltage of the main power supply to a first predetermined DC voltage.

Abstract: A fuel cell system includes a fuel cell for generating electric power by using a fuel, a valve module that controls a flow of a low concentration fuel circulating through the fuel cell, and a flow of a high concentration fuel supplied from a fuel storage unit to the fuel cell, a pump for pumping at least one of the low concentration fuel and the high concentration fuel according to a fuel flow control of the valve module; and a mixer for mixing and supplying the low concentration fuel and the high concentration fuel pumped from the pump to the fuel cell.

Abstract: A fuel cell system, which provides output power of at least one of a fuel cell and a battery to a load, selects any one operating mode from among various operating modes of the fuel cell system based on a change in performance of the battery due to use of the battery, and controls supplying of output power of the fuel cell and output power of the battery to the load according to the selected operating mode.

Abstract: A driving method of a fuel cell system, which includes a secondary battery and a fuel cell stack, is disclosed. The method includes detecting a state of charge (SOC) of the secondary battery, driving the fuel cell stack to an on-state whenever the SOC of the secondary battery is less than a predetermined first SOC, and driving the fuel cell stack to an off-state whenever the SOC of the secondary battery is greater than a predetermined second SOC. In this method, the fuel cell stack is driven at a fuel concentration having optimum efficiency, thereby increasing the fuel efficiency of the fuel cell system.

Abstract: A method of operating a fuel cell includes: generating an electrical power in a fuel cell stack while no fuel is being supplied from a fuel tank; reducing an output voltage of the electrical power toward a target voltage to increase an output current of the electrical power; measuring a rate of increase of the output current; starting supply of fuel to the fuel cell stack when the rate of increase of the output current is below a threshold rate; and controlling a fuel concentration in the fuel cell stack to maintain the output current at a target current level.

Abstract: A fuel cell system includes a fuel cell system connector and a fuel cartridge connector. The fuel cell system connector includes an external structure configured to accommodate a connector of a fuel cartridge and an internal structure mounted in the external structure. A contacting surface between the external structure and the internal structure of the fuel cell system connector includes a first nano-processed surface on a fuel supply path. The fuel cartridge connector includes an external structure having a retention key and an internal structure mounted in the external structure. A contacting surface between the external structure and the internal structure of the fuel cartridge connector includes a second nano-processed surface on a fuel supply path.

Abstract: A recycler of a fuel cell includes two electrodes, a rotor interposed between the two electrodes, and an insulating container surrounding and receiving the two electrodes and the rotor. A water management system of the fuel cell includes the recycler, and the fuel cell includes the water management system. A method of measuring a water level in the recycler includes measuring a conductivity of water separated in the recycler is measured.

Abstract: A fuel cell system having a fuel pressurizing system. The fuel cell system includes: a cartridge comprising a fuel storage pack; a main body; and a pressurizing unit disposed in the main body to pressurize the fuel storage pack when the cartridge is mated to the main body. The cartridge further includes a pressurizing plate to transmit pressure received from the pressurizing unit to the fuel storage pack when the cartridge is mated to the main body and to preventing the fuel storage pack from being pressurized when the cartridge is separated from the main body. The main body can include a case on which the fuel storage pack and the pressurizing plate are received.

Abstract: Provided is a fuel cell system including: a cartridge in which fuel is stored; a power unit producing power by using the fuel supplied from the cartridge; and a port to which an electronic device is connected, wherein the port comprises: a first channel which is a channel for receiving start-up power from the electronic device and supplying produced power to the electronic device; a second channel via which a signal indicating attachment of the fuel cell system to the electronic device is transmitted to the electronic device when the fuel cell system is attached to the electronic device; and a third channel for grounding.

Abstract: The present fluid pumping method for micro-fluidic devices uses gas bubbles to move fluid by light beams. The light beams are emitted to the fluid near the gas bubble through an optically transparent cover and correspondingly heat the fluid in the micro channels. The liquid temperature variation changes the surface tension of the gas bubble near the heated fluid side, therefore, a pressure gradient between the end portions of the gas bubble generates accordingly. By moving the light beams, the moved pressure difference will be achieved, which will drive the gas bubbles and pump the fluid. Such a fluid pumping can simplify the structure of a micro-fluidic device and eliminate heat loss because of using a controllable light beam.

Abstract: A water recovery system of a direct liquid feed fuel cell and a direct liquid feed fuel cell having the water recovery system. The water recovery system in which water produced at a cathode electrode of a membrane electrode assembly (MEA) is recovered to supply to an anode electrode, the water recovery system includes: a first member located on the cathode electrode and a first supporting plate that supports the first member; and a second member located on the anode electrode and a second supporting plate that supports the second member, wherein the first member and the second member are connected to each other through a slit formed in an electrolyte membrane of the MEA. The direct liquid feed fuel cell having the water recovery system can be used, for example, in a direct methanol fuel cell (DMFC).