Abstract: A bipolar plate, a fuel cell, and a fuel cell stack are provided. The bipolar plate includes a first flow-field plate and a second flow-field plate. The first flow-field plate and the second flow-field plate are stacked, and the edges of the first and second flow-field plates have a continuous welding portion to seal the periphery of the bipolar plate by a welding method.

Abstract: The present invention reduces or shuts off output electric power of a battery pack, which is connected to an electric device, depending on an abnormality. According to the present invention, a battery pack is detachably connected to an electric-device main body having a switch, and includes a first electric-power control circuit that outputs a first signal to the electric-device main body when the switch is operated, the first signal for allowing supply of electric power to the electric-device main body, a second switching element provided on an electric-power supply path that supplies electric power to the electric-device main body, and a second electric-power control circuit that outputs a second signal to the second switching element if an abnormality occurs in the battery pack, the second signal for reducing or shutting off the electric power supplied to the electric-device main body.

Abstract: Disclosed is a device for adjusting humidification gas of a membrane humidification device of a fuel cell. In particular, the device is adapted to induce changes in differential pressure and velocity of the wet air for each division module and to improve the humidification efficiency by sequentially mounting the division modules divided into various numbers to the interior of a housing of the membrane humidification device, thereby adjusting the density of the hollow fiber membrane filled in each division module.

Abstract: A lithium secondary battery is provided. The battery comprises: a positive electrode and a negative electrode which each has a specific composition and specific properties; and a nonaqueous electrolyte which contains a cyclic siloxane compound of formula (1), a fluorosilane compound of formula (2), a compound of formula (3), compound having an S—F bond in the molecule, nitric acid salt, nitrous acid salt, monofluorophosphoric acid salt, difluorophosphoric acid salt, acetic acid salt, or propionic acid salt in an amount of 10 ppm or more of the whole nonaqueous electrolyte.

Abstract: The printed battery has cathode and anode electrodes with terminals to connect to an external circuit, separator therebetween and electrolyte. An anode electrode material is applied on one side of the separator and a cathode electrode material on the opposite side. The anode material is dry and hydrophobic and is prepared by providing an anode active material, conductive material, solvent and a binder that are mixed to form an anode ink. The anode ink is applied on a substrate and then dried. In response to the drying, the solvent evaporates and the anode ink forms a film on the substrate. The prepared anode material is applied on the separator. An electrolyte solution is printed on the separator that has the anode material thereon. A cathode material is applied between a collector material and separator.