The disclosure relates to a method for using fuel cell. The fuel cell includes a container, wherein the container comprises a housing and a nozzle, and the housing defines through holes; the housing defines a chamber and an opening; the nozzle has a first end in air/fluid communication with the opening and a second end; and a membrane electrode assembly, which is flexible, on the container to form a curved membrane electrode assembly surrounding the chamber and covering the through holes, wherein the membrane electrode assembly comprises a proton exchange membrane having a first surface and a second surface, a cathode electrode on the first surface and an anode electrode on the second surface. The method includes at least partially immersing the fuel cell in a fuel; and supplying an oxidizing gas into the chamber.

The disclosure relates to a method for using fuel cell. The fuel cell includes a container, wherein the container comprises a housing and a nozzle, and the housing defines through holes; the housing defines a chamber and an opening; the nozzle has a first end in air/fluid communication with the opening and a second end; and a membrane electrode assembly, which is flexible, on the container to form a curved membrane electrode assembly surrounding the chamber and covering the through holes, wherein the membrane electrode assembly comprises a proton exchange membrane having a first surface and a second surface, a cathode electrode on the first surface and an anode electrode on the second surface. The method includes at least partially immersing the fuel cell in a fuel; and supplying an oxidizing gas into the chamber.

To provide a liquid composition with which a catalyst layer and a polymer electrolyte membrane will hardly be broken at the time of their formation and a method for producing the liquid composition; and a method for producing a membrane/electrode assembly by which a catalyst layer and a polymer electrolyte membrane will hardly be broken at the time of their formation.

A liquid composition comprising a polymer having ion exchange groups, water and an organic solvent, wherein the average secondary particle size of the polymer having ion exchange groups is from 100 to 3,000 nm, and the primary particle size parameter represented by the product of the average primary particle size (nm) and the ion exchange capacity (meq/g dry resin) of the polymer having ion exchange groups, is from 12 to 20.

To provide a liquid composition with which a catalyst layer and a polymer electrolyte membrane will hardly be broken at the time of their formation and a method for producing the liquid composition; and a method for producing a membrane/electrode assembly by which a catalyst layer and a polymer electrolyte membrane will hardly be broken at the time of their formation.

A liquid composition comprising a polymer having ion exchange groups, water and an organic solvent, wherein the average secondary particle size of the polymer having ion exchange groups is from 100 to 3,000 nm, and the primary particle size parameter represented by the product of the average primary particle size (nm) and the ion exchange capacity (meq/g dry resin) of the polymer having ion exchange groups, is from 12 to 20.

Disclosed is a membrane-electrode assembly having increased active area, improved fluid management capability, and decreased gas transfer resistance due to electrodes having patterned structures on both sides. Also disclosed are a method for manufacturing same, and a fuel cell comprising same. A membrane-electrode assembly according to the present invention comprises: a first electrode; a second electrode; and a polymer electrolyte membrane between the first and second electrodes, wherein the first electrode has a first surface facing the polymer electrolyte membrane and a second surface opposite the first surface, the first surface having a first patterned structure, and the second surface having a second patterned structure.

Disclosed is a membrane-electrode assembly having increased active area, improved fluid management capability, and decreased gas transfer resistance due to electrodes having patterned structures on both sides. Also disclosed are a method for manufacturing same, and a fuel cell comprising same. A membrane-electrode assembly according to the present invention comprises: a first electrode; a second electrode; and a polymer electrolyte membrane between the first and second electrodes, wherein the first electrode has a first surface facing the polymer electrolyte membrane and a second surface opposite the first surface, the first surface having a first patterned structure, and the second surface having a second patterned structure.

The invention relates to a method for ascertaining the overvoltage of a working electrode in a fuel cell, in which the potential of a reference electrode compared to the grounded counter electrode is measured. For the measurement, a fuel cell comprising a polymer electrolyte membrane is used, in which the counter electrode comprises a lateral edge having at least one convexly curved region, and the electrolyte membrane surface, adjoining the counter electrode, comprises an electrode-free region in which the reference electrode is disposed on the electrolyte membrane surface. In contrast, the working electrode is continuous, which is to say has a large surface. The minimum distance L.sub.gap between the reference electrode and the edge of the counter electrode L.sub.gap=3L.sub.l,r with (a) and (b), where m=ionic conductivity of the electrolyte membrane (.sup.1 cm.sup.1), b.sub.ox=Tafel slope of the half cell for the electrochemical reaction of the working electrode l.sub.m=membrane layer thickness (cm) and j.sub.ox.sup.0=exchange current density of the catalyst of the working electrode per unit of electrode surface in (A cm.sup.2). This arrangement can advantageously be used to ensure that the potential measured at the hydrogen-fed reference electrode corresponds to the overvoltage of the working electrode with sufficient accuracy. The method can be applied to polymer electrolyte membrane fuel cells (PEMFC), to direct methanol fuel cells (DMFC) or to high-temperature fuel cells (SOFC).

The disclosure relates to a fuel cell module. The fuel cell module includes a container and a membrane electrode assembly located on the container. The container includes a housing and a nozzle connected to the housing. The container defines a number of through holes located on the housing and covered by the membrane electrode assembly. The membrane electrode assembly includes a proton exchange membrane having a first surface and a second surface opposite to the first surface, a cathode electrode located on the first surface and an anode electrode located on the second surface.

The disclosure relates to a fuel cell module. The fuel cell module includes a container and a membrane electrode assembly located on the container. The container includes a housing and a nozzle connected to the housing. The container defines a number of through holes located on the housing and covered by the membrane electrode assembly. The membrane electrode assembly includes a proton exchange membrane having a first surface and a second surface opposite to the first surface, a cathode electrode located on the first surface and an anode electrode located on the second surface.

A fuel cell stack is comprised of a plurality of power generating units which are stacked along the horizontal direction. An oxidant gas inlet port and a fuel gas inlet port are provided in an upper portion of one of the power generating units, and an oxidant gas outlet port and a fuel gas outlet port are provided in the lower portion of the power generating unit. A refrigerant inlet port and a refrigerant outlet port are formed in each of the left and right portions of the power generating unit.