Abstract: A fuel cell has a structure in which generation modules are stacked. In each of the generation modules, there are cells are stacked. Each of the cells generates unitary power from fuel energy. A fuel cell system including the fuel stack operates either all or some of the generation modules in consideration of the quantity of power consumed by a load.

Abstract: A proton conductor includes a molecule with a hydroxy group arranged at a terminal end and an ether-based functional group arranged at an ?-carbon position. The proton conductor may be used to impregnate a polymer matrix to form a polymer electrolyte.

Abstract: A method of removing residual oxygen in a residential high temperature non-humidification fuel cell stack including at least one cathode. The method includes making the pressure in the cathode higher than that outside of the cathode and maintaining airtight sealing of the cathode of the fuel cell stack, removing the residual oxygen in the fuel cell stack, and stopping supplying of fuel to the fuel cell stack. The setting of the pressure includes blocking air flow out of the cathode, comparing the pressure in the cathode with a set pressure higher than the pressure outside the cathode, and supplying air to the cathode until the pressure in the cathode is the same as or is higher than the set pressure.

Abstract: A polymer electrolyte membrane includes a poly(benzoxazole) polymer doped with at least one acid. The polymer electrolyte membrane is manufactured by impregnating poly(benzoxazole) with an acid and has better ionic conductivity at high temperatures and better mechanical properties than a conventional poly(benzoxazole) polymer electrolyte membrane. In addition, the polymer electrolyte membrane has equivalent thermal stability to a conventional polymer electrolyte membrane.

Abstract: A polymer electrolyte that may be used in a fuel cell includes sulfonated polyether ketone ketone and a cross-linking agent.

Abstract: A polymer electrolyte that may be used in a fuel cell includes sulfonated polyether ketone ketone and a cross-linking agent.

Abstract: An electrode for fuel cells including a catalyst layer containing a benzoxazine monomer, a catalyst and a binder, and a fuel cell employing the electrode. The electrode for the fuel cells contains an even distribution of benzoxazine monomer, which is a hydrophilic (or phosphoric acidophilic) material and dissolves in phosphoric acid but does not poison catalysts, thereby improving the wetting capability of phosphoric acid (H3PO4) within the electrodes and thus allowing phosphoric acid to permeate first into micropores in electrodes. As a result, flooding is efficiently prevented. That is, liquid phosphoric acid existing in large amount within the electrodes inhibits gas diffusion which; this flooding occurs when phosphoric acid permeates into macropores in the electrodes. This prevention of flooding increases the three-phase interfacial area of gas (fuel gas or oxidized gas)-liquid (phosphoric acid)-solid (catalyst).

Abstract: Disclosed is a positive active material for a rechargeable lithium battery, including a lithiated intercalation compound and an additive compound. The additive compound comprises one or more intercalation element-included oxides which have a charging voltage of 4.0 to 4.6V when 5-50% of total intercalation elements of the one or more intercalation element-included oxides are released during charging.

Abstract: Crosslinked polybenzoxazines obtained by crosslinking a monofunctional first benzoxazine monomer and a multifunctional second benzoxazine monomer with a crosslinkable compound, an electrolyte membrane including the same, a method of preparing the electrolyte membrane, a fuel cell including the electrolyte membrane having the crosslinked polybenzoxazines using the method. The crosslinked polybenzoxazines have strong acid trapping capability, improved mechanical properties, and excellent chemical stability as it does not melt in polyphosphoric acid. Even as the amount of impregnated proton carrier and the temperature are increased, mechanical and chemical stability is highly maintained, and thus the electrolyte membrane can be effectively used for fuel cells at a high temperature.

Abstract: An electrolyte membrane includes a cross-linked reaction product of a benzoxazine monomer and a cross-linkable compound. The electrolyte membrane is impregnated with 300 to 600 parts by weight of phosphoric acid based on 100 parts by weight of the electrolyte membrane, and has a yield strain 0.5% or less, and a yield stress 0.3 Mpa or less. The cross-linked material has a strong acid trapping ability with respect to the benzoxazine compound and excellent mechanical properties due to a cross-linkage. Also, the solubility of the cross-linked material in polyphosphoric acid is low, thereby showing excellent chemical stability. Accordingly, when the cross-linked material is used, an electrolyte membrane having an excellent liquid supplementing ability and excellent mechanical and chemical stability at a high temperature can be obtained.

Abstract: A crosslinked object of a polybenzoxazine-based compound formed of a polymerized resultant of a first monofunctional benzoxazine-based monomer or a second multifunctional benzoxazine-based monomer with a crosslinkable compound, an electrolyte membrane including the crosslinked object, a method of preparing the electrolyte membrane, and a fuel cell employing the electrolyte membrane including the crosslinked object. The crosslinked object has a strong acid trapping capability with respect to the benzoxazine-based compound and high mechanical properties due to the crosslinking. The crosslinked object is very stable chemically because of elimination of solubility in polyphosphoric acid. The electrolyte membrane including the crosslinked object has excellent phosphoric acid supplementing capacity at a high temperature and mechanical and chemical stability.

Abstract: A polymer electrolyte membrane for use in a fuel cell and a method of producing a polymer electrolyte membrane. The method includes preparing a phosphate monomer solution by dissolving an initiator and a phosphate monomer containing at least one phosphoric acid group and at least one unsaturated bond in a solvent, impregnating a porous polymer matrix with the phosphate monomer solution, polymerizing the impregnated phosphate monomer, and impregnating the result of polymerization with a phosphoric acid.

Abstract: Provided are a polymer electrolyte membrane and a fuel cell including the same. The polymer electrolyte membrane has a phosphoric acid that is substituted with an aliphatic hydrocarbon. The polymer electrolyte membrane has excellent ion conductivity, heat resistance, and liquid-holding properties. The fuel cell including the polymer electrolyte membrane exhibits excellent performance.

Abstract: A polymer electrolyte membrane, a method of preparing the polymer electrolyte membrane, and a fuel cell including the polymer electrolyte membrane are disclosed in which the polymer electrolyte membrane includes a porous polymer matrix, and an ionic conductive polymer layer coated on the external surfaces of single fibers and inside pores of the porous polymer matrix.

Abstract: A polymer electrolyte membrane includes a poly(benzoxazole) polymer doped with at least one acid. The polymer electrolyte membrane is manufactured by impregnating poly(benzoxazole) with an acid and has better ionic conductivity at high temperatures and better mechanical properties than a conventional poly(benzoxazole) polymer electrolyte membrane. In addition, the polymer electrolyte membrane has equivalent thermal stability to a conventional polymer electrolyte membrane.

Abstract: A proton conductor includes a molecule with a hydroxy group arranged at a terminal end and an ether-based functional group arranged at an ?-carbon position. The proton conductor may be used to impregnate a polymer matrix to form a polymer electrolyte.

Abstract: A polymer electrolyte that may be used in a fuel cell includes sulfonated polyether ketone ketone and a cross-linking agent.

Abstract: A nonaqueous electrolyte for improving overcharge safety of a lithium battery using the same includes an organic solvent, a lithium salt, and a hydride of a compound represented by the Formula 1: R1, R2, R3, R4, R5, R6, R7, R8, R9, R10, R11, R12, R13 and R14 are the same or different, and are independently hydrogen, halogen, a substituted or unsubstituted C1–C20 alkyl, a substituted or unsubstituted C1–C20 alkoxy, nitro or amine group. The nonaqueous electrolyte forms a polymer due to its oxidative decomposition even if there is an increase in voltage due to overcharge of a battery by some uncontrollable conditions.

Abstract: The present invention relates to a polymer electrolyte membrane that includes a porous polymer matrix and an ion conducting polymer coating membrane formed in the outer surface of single fibers in the porous polymer matrix. The polymer electrolyte membrane can provide excellent mechanical strength, is not deteriorated by heat even at a temperature higher than 100°C., can provide excellent ion conductivity even at non-humidified state. Thus it is suitable for use in a fuel cell that is operated at high temperatures.

Abstract: The present invention provides a novel non-humidified polymer electrolyte and a fuel cell including the same. The non-humidified polymer electrolyte comprises an ion medium comprising an organic compound that has a boiling point greater than 100° C. and a dielectric constant greater than 3. The non-humidified polymer electrolyte further comprises a matrix comprising an ion conducting polymer, wherein the ion medium is impregnated into the matrix.