Abstract: An embodiment solid electrolyte includes a first compound and a second compound. The first compound is represented by a first chemical formula Li7-aPS6-a(X11-bX2b)a, wherein X1 and X2 are the same or different and each represents F, Cl, Br, or I, and wherein 0<a?2 and 0<b<1, and the second compound is represented by a second chemical formula Li7-cP1-2dMdS6-c-3d(X11-eX2e)c, wherein X1 and X2 are the same or different and each represents F, Cl, Br, or I, wherein M represents Ge, Si, Sn, or any combination thereof, and wherein 0<c?2, 0<d<0.5, and 0<e<1.

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 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 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: Fuel recycling apparatuses and fuel cell systems using the same are provided. The fluid recycling apparatus includes a porous member having first and second ends, a first electrode coupled to the first end of the porous member, a second electrode coupled to the second end of the porous member, and a power supplier for applying a constant voltage between the first electrode and the second electrode. The porous member moves a liquid from the first end of the porous member to the second end of porous member and discharges a gas under the voltage applied by the power supplier.

Abstract: An apparatus for supplying mixed fuel includes a water container storing water; a fuel container storing fuel, including at least gaseous fuel, the fuel container being coupled to the water container by a pressure pipe for transferring internal pressure of the fuel container to the water container; and a mixer coupled to the water container through a water supplying pipe and coupled to the fuel container through a fuel supplying pipe, the mixer outputting mixed fuel through a mixed fuel supplying pipe. A water supplying unit includes a water container storing water and connected to a water supplying pipe, the water container having an outlet; and a pressure applying unit coupled to the water container for applying gas pressure to an inside of the water container to discharge water from the water container through the outlet.

Abstract: An apparatus for supplying mixed fuel includes a water container storing water; a fuel container storing fuel, including at least gaseous fuel, the fuel container being coupled to the water container by a pressure pipe for transferring internal pressure of the fuel container to the water container; and a mixer coupled to the water container through a water supplying pipe and coupled to the fuel container through a fuel supplying pipe, the mixer outputting mixed fuel through a mixed fuel supplying pipe. A water supplying unit includes a water container storing water and connected to a water supplying pipe, the water container having an outlet; and a pressure applying unit coupled to the water container for applying gas pressure to an inside of the water container to discharge water from the water container through the outlet.

Abstract: A fuel cell reformer includes a main body having a first pipe with a second pipe inside the first pipe, a thermal source unit in the second pipe, a reforming reaction unit in a first region between the first pipe and the second pipe to generate a reforming gas containing hydrogen through a reforming reaction of a fuel, and a carbon monoxide reduction unit in a region other than the first region between the first pipe and the second pipe to reduce a concentration of carbon monoxide contained in the reforming gas. A thermal treatment unit in the main body supplies thermal energy to the reforming reaction unit and the carbon monoxide reduction unit at a time of initial driving of the reformer such that the supplied thermal energy corresponds to a unique operational temperature range in the reforming reaction unit, and to a unique operational temperature range in the carbon monoxide reduction unit.

Abstract: A reformer is disclosed for supplying a reformed gas containing hydrogen to a fuel cell. The reformer comprises a heat source; a preheating portion preheated by heat from the heat source; a pipe shaped reforming reaction unit; a carbon monoxide processing unit extending from the reforming reaction unit; and a rugged portion installed on an internal surface of the pipe shaped reforming reaction unit which is heated by the heat source. By using the rugged portion and the extended pipe design, the area heated by the heat source is increased and more heat is recovered, thereby improving thermal efficiency.

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: Fuel recycling apparatuses and fuel cell systems using the same are provided. The fluid recycling apparatus includes a porous member having first and second ends, a first electrode coupled to the first end of the porous member, a second electrode coupled to the second end of the porous member, and a power supplier for applying a constant voltage between the first electrode and the second electrode. The porous member moves a liquid from the first end of the porous member to the second end of porous member and discharges a gas under the voltage applied by the power supplier.

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 caries 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 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: An air and liquid separator used in a fuel cell, the air and liquid separator including: a fuel guidance pipe having one or more opening portions on a surface thereof; and an air and liquid separating film provided on the opening portions of the fuel guidance pipe and transmitting only gas. Accordingly, an air and liquid separator according to aspects of the present invention remove gas included in non-reactive fuel by using an air and liquid separating film, without any separate power sources, and supplies the non-reactive fuel to a fuel cell, enabling a more compact and high efficient fuel cell system.

Abstract: A catalyst for reforming a fuel and a fuel cell system including the same is provided. The catalyst for reforming a fuel includes at least one active metal selected from the group consisting of titanium (Ti), iron (Fe), chromium (Cr), nickel (Ni), cobalt (Co), vanadium (V), tungsten (W), molybdenum (Mo), manganese (Mn), tin (Sn), ruthenium (Ru), aluminum (Al), platinum (Pt), silver (Au), palladium (Pd), copper (Cu), rhodium (Rh), zinc (Zn), and mixtures thereof, supported on a metal foam, and a fuel cell system in which butane is used as a fuel, also including the same catalyst composition as a reforming catalyst for use in a reformer.

Abstract: A fuel cell reformer includes a main body having a first pipe with a second pipe inside the first pipe, a thermal source unit in the second pipe, a reforming reaction unit in a first region between the first pipe and the second pipe to generate a reforming gas containing hydrogen through a reforming reaction of a fuel, and a carbon monoxide reduction unit in a region other than the first region between the first pipe and the second pipe to reduce a concentration of carbon monoxide contained in the reforming gas. A thermal treatment unit in the main body supplies thermal energy to the reforming reaction unit and the carbon monoxide reduction unit at a time of initial driving of the reformer such that the supplied thermal energy corresponds to a unique operational temperature range in the reforming reaction unit, and to a unique operational temperature range in the carbon monoxide reduction unit.