Abstract: A fuel cell stack includes a stack including a plurality of unit cells, which is stacked on one another in a predetermined direction, first and second end plates disposed on opposing ends of the stack, and a supply line disposed on a first surface of the first end plate to supply fuel or air to the plurality of unit cells, where an insertion hole is defined in a second surface of the first end plate to be adjacent to the supply line, and the second surface of the first end plate is substantially perpendicular to the first surface of the first end plate.

Abstract: A fluid tube includes: a first fluid tube; a second fluid tube connected to the first fluid tube; and a flow velocity equalizer in the second fluid tube, where the flow velocity equalizer increases a uniformity of fluid flow passed therethrough, the second fluid tube is wider than the first fluid tube, and the flow velocity equalizer includes a diverging tube and a converging tube. The fluid tube may further include a fluid divider between the flow velocity equalizer and the first fluid tube. The diverging tube of the flow velocity equalizer may have a width increasing in a fluid flow direction, and the converging tube of the flow velocity equalizer may include a plurality of converging tubes having widths decreasing in the fluid flow direction.

Abstract: A cooling plate in which flow channels are modified to reduce temperature differences between portions of the cooling plate and provide for more uniform heat distribution within a heat generator. The flow channels of the cooling plate are formed such that a central portion of the flow channels has a greater volume than the end portions near an inlet and an outlet so that the amount of cooling water that is contained in the central portion at any one time is larger than either of the end portions near the inlet and the outlet. Likelihood of thermal deformation of the cooling plate due to thermal stress is decreased, and stability of performance of the fuel cell is increased.

Abstract: A fuel cell stack includes a first separating plate, a second separating plate corresponding to the first separating plate, a plurality of cells comprising a membrane electrode assembly disposed between the first separating plate and the second separating plate, and a cooling plate disposed between the plurality of cells, where a cooling channel is defined at opposing surfaces of the cooling plate.

Abstract: A fuel cell stack includes a plurality of unit cells, a cooling plate and a block plate. Each unit cell includes a cathode electrode and an anode electrode respectively at opposing sides of an electrolyte membrane, and a separator facing each of the cathode electrode and the anode electrode. The cooling plate is between adjacent unit cells a cooling medium flows in the cooling plate. The block plate is between the cooling plate and an adjacent unit cell of the adjacent unit cells. The block plate blocks the cooling medium flowing in the cooling plate from contacting the adjacent unit cell of the adjacent unit cells.

Abstract: A soft water forming device includes; a capacitive deionization stack (“CDI”) stack including at least one anode and at least one cathode that are separately and alternately stacked to adsorb ions contained in water, and a pumping unit which pumps one of water supplied to the CDI stack and water which has passed through the CDI stack, the pumping unit including; a casing have a water inlet and a water outlet and a rotor which rotates due to motive power supplied by an external motor and pumps the water supplied into the casing.

Abstract: A battery pack including battery cells, a housing to house the battery cells, and a cooling device that cools air flowing through the housing. The cooling device may be installed on an intermediate portion of the housing. The cooling device may include a cooling pipe, in which water flows.

Abstract: A method of activating a fuel cell includes: supplying a fuel to an anode of the fuel cell; supplying a gas mixture to a cathode of the fuel cell; applying a second load, which is equal to or less than a predetermined first load, to a stack of the fuel cell after supplying the gas mixture to the cathode; discontinuing the supply of the gas mixture; resupplying the gas mixture to the cathode when a voltage of the stack of the fuel cell is a predetermined voltage or less after discontinuing the supply of the gas mixture; and applying a third load, which is higher than the predetermined first load, to the stack of the fuel cell, where the supply of the fuel to the anode of the fuel cell is maintained.

Abstract: A fuel cell system in which a low open circuit voltage (OCV) is maintained in a start-up mode and in a shut-down mode, and a method of operating the same, the method including: supplying an anode off-gas and air to the cathode in an open circuit voltage state in a start-up mode and cutting off supply of the fuel gas to the cathode in a normal operating mode; and supplying the fuel gas and air to the cathode in a shut-down mode, and if a load is cut off, purging the cathode and the anode in the OCV state.

Abstract: An integrated electrode-current collector sheet includes a current collector including uneven portions disposed on at least one side of the current collector; and an active material layer disposed on the current collector, the active material layer at least partially covering the uneven portions. In addition, disclosed are a capacitive deionization device and an electric double layer capacitor including the integrated electrode-current collector sheet.

Abstract: A fuel cell system a includes a cooling water temperature raising unit that raises the temperature of a fuel cell stack by passing discharge gas of a process burner or hydrogen gas of a fuel processing unit and cooling water that is heated by the discharge gas of the process burner through flow paths formed on opposing surfaces of cooling separators formed of a metal and installed between a plurality of cells in the stack. Thus in the fuel cell system, when the temperature of the stack needs to be rapidly raised, for example, during a start up operation of the fuel cell system, the temperature of the stack can be rapidly raised using discharge gas at a high temperature or combustion heat of hydrogen gas, and heated cooling water, and thereby, significantly reducing the time required for the fuel cell system to be in regular operation.

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: There is provided a network apparatus capable of effectively retransmitting a frame in a frame aggregation environment, and a method of retransmitting a frame using the same. The network apparatus includes: a transmitting node broadcasting a plurality of data frames in a frame aggregation environment; a receiving node receiving the plurality of broadcast data frames and broadcasting a reception result; and at least one relay node receiving and storing at least a portion of the plurality of broadcast data frames and transmitting, together with the transmitting node, a data frame for which retransmission is required to the receiving node according to a calculated transmission success rate when the reception result from the receiving node is a retransmission request.

Abstract: A method of starting a polymer electrolyte membrane fuel cell (PEMFC) stack by rapidly increasing its temperature. The PEMFC stack includes: a first flow line connected to cooling plates; a second flow line connected to the cooling plates; a coolant reservoir; a heat exchanger; a by-pass line; a heating element; a first valve installed between the first flow line and the heat exchanger; and a second valve that selectively connects the coolant reservoir, the second flow line, and the by-pass line. The method of starting a PEMFC stack includes: closing the first valve and controlling the second valve so that the second flow line and the by-pass line are connected to each other, and the coolant in the coolant reservoir is not connected to the second flow line and the by-pass line; and heating the coolant in the by-pass line.

Abstract: Bipolar plates and a fuel cell stack having the bipolar plates. The fuel cell stack includes membrane electrode assemblies (MEAs), and first and second bipolar plates sequentially stacked between the MEAs. The bipolar plates include: flow channels formed on opposing surfaces thereof; four manifolds connected to the flow channels; and through holes to connect to the manifolds of the bipolar plates adjacent thereto.

Abstract: A bipolar plate includes a plurality of flow channels for fuel flow, wherein the flow channels are divided into a plurality of sections along a direction of the fuel flow. The total cross-sectional area of the flow channels across the sections becomes smaller from a fuel inlet toward a fuel outlet. A plurality of protrusions are formed between the sections, and the protrusions mix a fuel that passes through the flow channels. A fuel cell includes membrane electrode assemblies interposed between a plurality of the bipolar plates.

Abstract: A method of operating a high-temperature fuel cell, the method including increasing the temperature of a fuel cell stack the operation of which has stopped; starting the operation of the fuel cell stack and applying at least a portion of a load to the fuel cell stack when the temperature of the fuel cell stack reaches a first temperature; and applying any remaining load to the fuel cell stack when the temperature of the fuel cell stack reaches a second temperature that is higher than the first temperature.

Abstract: A unit cell of a fuel cell stack, and a fuel cell stack including the unit cell, where the unit cell includes channel plates including first and second manifolds, a plurality of channels and channel connecting units; hard plates arranged to contact surfaces of the channel connecting units; and gaskets arranged to surround the plurality of channels and first and second manifolds between the channel plates and the hard plates.

Abstract: A stack and a method of operating the stack. A method of operating a stack having a plurality of cells and a plurality of cooling plates includes: supplying a working fluid to a first group of the cooling plates; and re-supplying the working fluid passed through the first group of the cooling plates to a second group of the cooling plates, wherein the first and second groups are divided according to an operating temperature in the stack.

Abstract: A passive cooling system for a fuel cell stack is provided. The passive cooling system includes a plurality of cooling plates, each installed between every few unit cells, each having flow channels for flowing a primary coolant on at least one surface, and each comprising an inlet hole through which the primary coolant enters and an outlet hole through which the primary coolant that has passed the flow channels leaves; and a heat exchanger installed on a primary coolant flow line connected from the outlet holes to the inlet holes of the cooling plates to change a vapor state primary coolant to a liquid state primary coolant by cooling the primary coolant, wherein a path through which the primary coolant passes is a closed circuit, and the flow of the primary coolant is achieved by natural convection caused by vaporization of the primary coolant.