Abstract: Provided is electrically conductive ink that shows favorable flowability and that can also suppress deformation, such as flattening, upon application of surface pressure. The electrically conductive ink is applied onto a substrate 21 of a separator 11 that constitutes a cell 13 of a fuel cell stack by way of screen printing so as to form ribs 22 on the substrate 21, wherein the electrically conductive ink has viscoelasticity, as measured by a rotary rheometer, that exhibits a loss tangent of 1 with a strain of 10 to 100%.

Abstract: Provided is electrically conductive ink that shows favorable flowability and that can also suppress deformation, such as flattening, upon application of surface pressure. The electrically conductive ink is applied onto a substrate 21 of a separator 11 that constitutes a cell 13 of a fuel cell stack by way of screen printing so as to form ribs 22 on the substrate 21, wherein the electrically conductive ink has viscoelasticity, as measured by a rotary rheometer, that exhibits a loss tangent of 1 with a strain of 10 to 100%.

Abstract: A fuel cell system includes a fuel cell, anode gas pressure adjusting means that adjusts the pressure of an anode gas supplied to the fuel cell, and cathode gas pressure adjusting means that adjusts the pressure of a cathode gas supplied to the fuel cell. The system further includes pressure control means that sets the pressure of the anode gas that is supplied when starting the fuel cell higher than the pressure of the anode gas that is supplied during power generation in the fuel cell, and controls the anode gas pressure adjusting means and the cathode gas pressure adjusting means so that a cathode gas pressure increase is started in accordance with the start of an anode gas pressure increase when the pressure of the anode gas is increased to the set pressure.

Abstract: There are provided a membrane electrode assembly in which favorable water circulation is brought about within a cell and which is superior in self-humidification performance, and a fuel cell stack comprising fuel cells comprising such a membrane electrode assembly. A membrane electrode assembly 4 comprises: an electrolyte membrane 1; and an anode-side catalyst layer 3 and a cathode-side catalyst layer 2, which are respectively disposed on both sides of the electrolyte membrane 1 and which comprise a catalyst support, in which a catalyst is supported on a conductive support, and a polymer electrolyte. With respect to this anode-side catalyst layer 3, I/C (i.e., the ratio of the mass of the polymer ionomer (I) to the mass of the conductive support (C)) is within the range of 1.0 to 2.0, EW (sulfonic acid equivalent weight) is within the range of 750 to 1,100, and polymer electrolyte thickness is within the range of 10 nm to 24 nm.

Abstract: A fuel cell system includes a fuel cell, anode gas pressure adjusting means that adjusts the pressure of an anode gas supplied to the fuel cell, and cathode gas pressure adjusting means that adjusts the pressure of a cathode gas supplied to the fuel cell. The system further includes pressure control means that sets the pressure of the anode gas that is supplied when starting the fuel cell higher than the pressure of the anode gas that is supplied during power generation in the fuel cell, and controls the anode gas pressure adjusting means and the cathode gas pressure adjusting means so that a cathode gas pressure increase is started in accordance with the start of an anode gas pressure increase when the pressure of the anode gas is increased to the set pressure.

Abstract: A fuel cell is provided with a membrane-electrode assembly 15 in which catalyst layers 15b as a pair of electrodes are bonded to both the surfaces of an electrolyte membrane 15a, and diffusion layers 16 arranged on both the surfaces of this membrane-electrode assembly 15. The membrane-electrode assembly 15 and the diffusion layer 16s are laminated without bonding at least a part between the membrane-electrode assembly 15 and the diffusion layers 16. Thus, sliding and separating between the catalyst layer 15b and the diffusion layers 16 are allowed.