Abstract: A fuel cell with a recovering unit and a method of driving the same are disclosed. In one embodiment, the fuel cell includes i) an electric generator to generate electricity based on electrochemical reaction, ii) a recovering unit to recover and mix the fuel, unreacted fuel, and gas and water produced by the electrochemical reaction, and supply the mixed fuel to the electric generator, wherein the recovering unit comprises a valve, configured to discharge gas, which is selectively opened and closed depending on the operation of the fuel cell. With this configuration, the gas or the fuel is not introduced into the electric generator, even though the recovering unit is inclined or turned over. Further, even though the fuel cell is not in use for a long time, the mixed fuel is prevented from evaporating through the discharging pipe.

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 fuel cell system includes: a fuel cell stack for generating electrical energy by reacting oxidant and mixed fuel, and for discharging non-reacted fuel, oxidant, moisture, and carbon dioxide; a mixer for preparing the mixed fuel by mixing at least a portion of the non-reacted fuel, oxidant and moisture with concentrated fuel and for supplying the mixed fuel to the fuel cell stack; a fuel supply unit for supplying the concentrated fuel to the mixer; an oxidant supply unit for supplying the oxidant to the fuel cell stack; a first heat exchanger between an outlet of the fuel cell stack and the mixer; and a second heat exchanger between the mixer and an inlet of the fuel cell stack.

Abstract: A fuel cell system is disclosed. The fuel cell system may include a fuel cell stack configured for generating electrical energy by a reaction of an oxidant and a fuel, a recovery unit including a first gas liquid separator configured for separating a by-product discharged by the fuel cell stack into a first gas and a first liquid, a first heat exchanger configured for cooling the first gas supplied by the first gas liquid separator, and a second gas liquid separator configured for separating a by-product supplied by the first heat exchanger into a second gas and a second liquid, and a remover unit fluidly connected to the second gas liquid separator and configured for removing the second gas from the recovery unit.

Abstract: A gas-liquid separator including a housing, a first absorbing member, a second absorbing member, and a liquid pump is disclosed. The housing may include an inflow port, a gas outlet port, and a liquid outlet port. The first absorbing member may be disposed contacting the liquid outlet port in an inner space of the housing. The first absorbing member may be configured to absorb liquid in a gas-liquid mixture received from the inlet port. The second absorbing member may be disposed apart from the first absorbing member in the inner space of the housing. The second absorbing member may have a smaller volume than the absorbing member.

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: The disclosed is a density sensing device of a fuel cell system and a fuel cell system having the density sensing device. The density sensing device includes a density sensor that includes a collision sensor and a variable resistor coupled to the collision sensor. The collision sensor is dipped into a fuel solution, and the collisions of molecules of the fuel solution are detected in the collision sensor. The resistance of the variable resistor varies depending on an amount of the collision detected by the collision sensor. The resistance further is converted to a density by the use of a table that includes a relationship between resistance and density. The density sensing device can further include a sensor driver. The sensor driver can be a piezoelectric member that is attached to the collision sensor. The collision sensor vibrates together with the piezoelectric member when a driving signal is applied to the piezoelectric member, which improves the accuracy of the measurement of the density.

Abstract: A fuel cell system having an excellent orientation free performance by separating a fluid into a liquid and a gas without being affected by shaking and/or rotation of the fuel cell system includes a fuel cell main body, a first liquid/gas separation unit, and a buffer line. The fuel cell main body receives a fuel containing hydrogen and an oxidizing gas containing oxygen and generates electrical energy through an electrochemical reaction between the hydrogen and the oxygen. The first gas/liquid separation unit is installed on a first recycling line extending from an anode outlet of the fuel cell main body to separate a gas byproduct from unreacted fuel discharged through the anode outlet.

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 having an excellent orientation free performance by separating a fluid into a liquid and a gas without being affected by shaking and/or rotation of the fuel cell system includes a fuel cell main body, a first liquid/gas separation unit, and a buffer line. The fuel cell main body receives a fuel containing hydrogen and an oxidizing gas containing oxygen and generates electrical energy through an electrochemical reaction between the hydrogen and the oxygen. The first gas/liquid separation unit is installed on a first recycling line extending from an anode outlet of the fuel cell main body to separate a gas byproduct from unreacted fuel discharged through the anode outlet.

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 method and an apparatus for controlling the operation of a fuel cell system. The method can include, actively controlling the fuel cell system without a fuel concentration sensor by: measuring an output voltage, an output current, and a temperature of a fuel cell stack; obtaining a first fuel feeding amount corresponding to the measured output values; comparing a reference temperature corresponding to the measured output values with the measured temperature; and obtaining a second fuel feeding amount by compensating the first fuel feeding amount with a value corresponding to difference between the reference temperature and the measured temperature.

Abstract: A module-type fuel cell system including a power module includes a generator installed inside and a power housing having a plurality of connection holes formed sideward, wherein the generator generates electricity through an oxidation-reduction reaction of an oxidizing agent with a hydrogen-containing fuel; a fuel supply module including a fuel supply unit installed inside and a power housing having a plurality of connection holes formed sideward, wherein the fuel supply unit supplies a hydrogen-containing fuel to the generator; an oxidizing agent supply module including an oxidizing agent supply unit installed inside and an oxidizing agent supply housing having connection holes formed sideward, wherein the oxidizing agent supply unit supplies an oxidizing agent to the generator; and a recovery module including a storage space formed therein and a recovery housing having a plurality of connection holes formed sideward, wherein the storage space recovers an unreacted fuel generated in the generator, wherein th

Abstract: A fuel cell system, which can supply a stable flow rate of fuel to a fuel cell stack is disclosed. The fuel cell system may include a fuel cell stack for generating electricity by an electrochemical reaction of a fuel and an oxidizing agent, a fuel supply unit for supplying a fuel to the fuel cell stack, an oxidizing agent supply unit for supplying an oxidizing agent to the fuel cell stack, and a flow rate controller installed between the fuel cell stack and the fuel supply unit. The fuel cell system may include a feed pump for pressurizing the fuel, a first resistor connected to the front end of the feed pump to reduce flow rate and a second resistor connected to the rear end of the feed pump to reduce flow rate. A method of operating a fuel cell system is also disclosed. The method may include supplying fuel to a fuel cell stack from a fuel supply unit, reducing a flow rate by a first resistor, activating a feed pump, reducing a flow rate by a second resistor, and stopping the feed pump.

Abstract: A battery pack that is charged with power generated in an external power generator and supplies battery power to an external load in parallel with the external power generator, and a power receiving device of a portable electronic device that receives and supplies battery power to an external load in parallel with the external power generator, the battery pack including: a battery cell to discharge power based on a charged amount of electric charge; an external power input terminal to receive power from an external power generator; a power output terminal to supply power to an external load; and a voltage transforming circuit to transform voltage of the power received through the external power input terminal to transfer the transformed voltage to the power output terminal.

Abstract: A fuel cell system includes: a fuel cell stack for generating electrical energy by reacting oxidant and mixed fuel, and for discharging non-reacted fuel, oxidant, moisture, and carbon dioxide; a mixer for preparing the mixed fuel by mixing at least a portion of the non-reacted fuel, oxidant and moisture with concentrated fuel and for supplying the mixed fuel to the fuel cell stack; a fuel supply unit for supplying the concentrated fuel to the mixer; an oxidant supply unit for supplying the oxidant to the fuel cell stack; a first heat exchanger between an outlet of the fuel cell stack and the mixer; and a second heat exchanger between the mixer and an inlet of the fuel cell stack.

Abstract: An improved fluid recycling apparatus and a fuel cell system comprising the same effectively recycle moisture contained in fluid circulating in a fuel cell system and operate independent of orientation. The fluid recycling apparatus includes an electric penetration pump and a gas/liquid separation unit. The electric penetration pump has first and second electrodes and an electric penetration layer interposed between the first and second electrodes. The electric penetration pump directs a liquefied fluid through an electric fluid passage formed in the electric penetration layer by applying a voltage between the first electrode and the second electrode. The gas/liquid separation unit is disposed upstream of the electric fluid passage, contacting the electric penetration pump, and comprises a porous material that can absorb the liquefied fluid.

Abstract: A fuel cell system having an excellent orientation free performance by separating a fluid into a liquid and a gas without being affected by shaking and/or rotation of the fuel cell system includes a fuel cell main body, a first liquid/gas separation unit, and a buffer line. The fuel cell main body receives a fuel containing hydrogen and an oxidizing gas containing oxygen and generates electrical energy through an electrochemical reaction between the hydrogen and the oxygen. The first gas/liquid separation unit is installed on a first recycling line extending from an anode outlet of the fuel cell main body to separate a gas byproduct from unreacted fuel discharged through the anode outlet.

Abstract: A fuel cell system including a correction means capable of accurately correcting a concentration sensing value according to temperature is discussed. The fuel cell system may include an electricity generating unit generating electric energy by means of the electrochemical reaction of fuel and an oxidizer, a fuel supplying unit supplying the fuel to the electricity generating unit, a main concentration sensor for measuring the concentration of the fuel, a reference cell filled with reference solution and including a reference concentration sensor for measuring the concentration of the reference solution, and/or a drive controlling unit controlling the operation of the electricity generating unit based on the concentration values measured in the main concentration sensor and the reference concentration sensor.