Abstract: A temperature measuring instrument is provided with a testing switch that controls a supply of a first constant current to a first signal line from a first constant current source and a supply of a second constant current to a second signal line from a second constant current source. When a temperature is being measured, the first and second constant currents are supplied respectively to the first and second signal lines. When testing connection statuses of the first signal line, the second signal line and a third signal line, the supply of the first and second constant currents are stopped temporarily, to change a report from a current detecting/reporting portion, provided in a temperature sensor, for detecting and reporting whether or not there is a return current to the temperature measuring instrument from the third signal line.

Abstract: A charging method including the steps of: supplying oxidant at a first flow rate AQ to a fuel cell; supplying fuel at a second flow rate FQ to the fuel cell; charging a lead-acid battery with electric power generated by the fuel cell, with an output current If of the fuel cell being kept constant; reducing a charge current Ib along with increasing a battery voltage Eb of the lead-acid battery; reducing the output current If so as to make an output voltage Ef of the fuel cell equal to or more than a lower-limit voltage value DE when the output voltage Ef drops to the lower-limit voltage value DE as the electric power generated by the fuel cell decreases; and reducing the output current If when the battery voltage Eb reaches a first upper-limit voltage ER1, (n?1) times, from a 1st current If (1) to an nth current If (n).

Abstract: A temperature measuring instrument is provided with a testing switch that controls a supply of a first constant current to a first signal line from a first constant current source and a supply of a second constant current to a second signal line from a second constant current source. When a temperature is being measured, the first and second constant currents are supplied respectively to the first and second signal lines. When testing connection statuses of the first signal line, the second signal line and a third signal line, the supply of the first and second constant currents are stopped temporarily, to change a report from a current detecting/reporting portion, provided in a temperature sensor, for detecting and reporting whether or not there is a return current to the temperature measuring instrument from the third signal line.

Abstract: Disclosed is a fuel cell system that is capable of improved power generating performance and reduced size, and furthermore, is very safe. The system includes a membrane electrode assembly (MEA), a fuel tank, a liquid collecting tank, a two-liquid-joining unit, a first fuel supply unit, a second fuel supply unit, and a fuel filter. The fuel tank stores a liquid fuel. The liquid collecting tank stores a liquid discharged from at least one of an anode or a cathode in the MEA, as a collected liquid. The two-liquid-joining unit prepares a diluted fuel by mixing the liquid fuel and the collected liquid. The first fuel supply unit supplies the liquid fuel to the two-liquid-joining unit. The second fuel supply unit supplies the diluted fuel to the anode. The fuel filter, disposed between the two-liquid-joining unit and the anode, removes impurities in the diluted fuel.

Abstract: The amount of fuel supplied to a fuel cell is set to a second set value Qm2 smaller than a first set value Qm1 determined based on a load. Then, an output current Ifcr of the fuel cell with the fuel supply amount set to the second set value Qm2 is detected. The output current Ifcr is compared with a reference value Iref for determining mild deterioration to determine whether the fuel cell has deteriorated from the comparison result. If a determination that the fuel cell has deteriorated is made, the fuel supply amount is reset to a third set value Qm3 larger than the second set value Qm2.

Abstract: Disclosed is a fuel cell system comprising: a fuel cell including an anode and a cathode to which a water-soluble fuel and an oxidant are supplied, respectively, and a water-permeable electrolyte membrane interposed therebetween; a fuel tank; a first fuel supply unit which supplies an aqueous fuel solution to the anode; a second fuel supply unit which supplies the fuel to the first fuel supply unit; an oxidant supply unit which supplies an oxidant to the cathode; a temperature sensor which detects a temperature FT of the fuel cell; and a control unit which controls the first, second, and oxidant supply units, and the fuel cell whether to start or stop power generation. The control unit allows at least the first fuel supply unit to operate while the fuel cell is stopped from generating power, provided that the temperature FT of the fuel cell as such meets specific requirements.

Abstract: A direct oxidation fuel cell system including: a fuel cell which generates power from fuel and oxidant gas; a positive displacement pump for supplying the oxidant gas; a power supply for applying drive voltage to the pump; an oxidant gas flow conditioning unit for inhibiting pulsation of discharge pressure of the pump; a pressure sensor for detecting the discharge pressure; a load current sensor for detecting load current of the cell; a voltage sensor for detecting the drive voltage; a first memory for storing first information on a target supply flow rate of the oxidant gas, set based on the load current; a second memory for storing second information on relation of the drive voltage, discharge pressure, and target supply flow rate; and a controller for controlling flow rate of the oxidant gas, by using the informations, and values from the pressure, load current, and voltage sensors.

Abstract: Deterioration of a fuel cell is accurately determined within a short period of time by the steps of: (a) detecting an output power P of a fuel cell; (b) detecting a peak of the output power P after a startup of the fuel cell; (c) calculating a decrease rate D of the output power P after the peak of the output power P; (d) comparing the calculated decrease rate D with a reference decrease rate Dref; and (e) determining deterioration of the fuel cell based on a comparison result of the step (d).

Abstract: A direct oxidation fuel cell system including: a fuel cell; a fuel supply portion for supplying a liquid fuel to a fuel inlet; an oxidant supply portion for supplying an oxidant to an oxidant inlet; an effluent tank for storing a fuel effluent; a fuel discharge path for leading the fuel effluent to the effluent tank; a gas-liquid separation mechanism for separating a part of product water from a fluid containing unconsumed oxidant and product water and discharging the remainder to outside; and a product water discharge path for leading the separated product water to the effluent tank. The gas-liquid separation mechanism has: a vent hole communicating with the oxidant outlet and outside; a porous filter for closing the vent hole; and a water-absorbent material for partially covering the surface of the porous filter on the oxidant outlet side.

Abstract: A fuel supply apparatus for supplying a liquid fuel to a device having a fuel cell which uses the liquid fuel is provided. The fuel supply apparatus includes: a container containing the liquid fuel and being configured to be detachably attached to the device; and a joint for connecting the container and the device. The joint has a double tube structure including an outer tube and an inner tube. One of the outer tube and the inner tube forms a flow path through which the liquid fuel in the container flows into the device by gravity, while the other tube forms a flow path through which a replacement fluid spontaneously flows into the container to replace the liquid fuel.

Abstract: A fuel cell system has a separation unit for separating gas-liquid mixed fluid discharged from the fuel cell stack. The separation unit has a tank for storing the separated liquid. A pair of metal electrodes is disposed on the side surfaces of the tank opposed to each other. The electrodes are used to measure the amount of the liquid in the tank and also promote the heat dissipation of the liquid in the tank. This can suppress the transpiration of the liquid in the tank and cool the liquid to a temperature suitable for the reuse in the fuel cell stack.

Abstract: The amount of fuel supplied to a fuel cell is set to a second set value Qm2 smaller than a first set value Qm1 determined based on a load. Then, an output current Ifcr of the fuel cell with the fuel supply amount set to the second set value Qm2 is detected. The output current Ifcr is compared with a reference value Iref for determining mild deterioration to determine whether the fuel cell has deteriorated from the comparison result. If a determination that the fuel cell has deteriorated is made, the fuel supply amount is reset to a third set value Qm3 larger than the second set value Qm2.

Abstract: A connector unit includes a communication line connecting a receiving port of a physical layer unit of a node to one adjacent node, and a communication line connecting a transmitting port of the physical layer unit to the one adjacent node via a capacitor, and a connector unit includes a communication line for connecting a receiving port of a physical layer unit of the node to the other adjacent node, and a communication line for connecting a transmitting port of the physical layer unit to the other adjacent node via a capacitor, wherein the connector unit is connected to a connector unit of the one adjacent node, so that the communication line of the node is connected to the communication line of the one adjacent node, and the communication line of the node is connected to the communication line of the one adjacent node.

Abstract: A fuel cell system includes: a fuel cell; a power storage unit for storing power generated by the fuel cell; a tank for storing a fuel to be supplied to the fuel cell; a remaining fuel sensor for detecting the amount of fuel remaining in the tank; an SOC detector for detecting the state of charge of the power storage unit; and a control unit for controlling the operation of the fuel cell. (i) When the remaining amount of fuel is larger than a predetermined value A, the control unit is configured to perform: (a) an operation for stopping the power generation of the fuel cell or an operation for decreasing the amount of power generated if the state of charge is equal to or more than a predetermined value X; and (b) an operation for starting the power generation of the fuel cell or an operation for increasing the amount of power generated if the state of charge is equal to or less than a predetermined value Y where Y<X.

Abstract: In a method for controlling a flow rate of fuel supplied to a fuel cell, a voltage change is examined while the flow rate of the fuel is increased step by step in a state in which a constant current is output. Conversely, when the voltage change becomes small, the flow rate of fuel is reduced step by step. When the voltage change becomes large, the flow rate of the fuel in the previous step is employed. Thus, the flow rate of fuel can be optimized in accordance with an operating state of the fuel cell.

Abstract: A fuel cell system for optimally controlling an amount and temperature of liquid component stored in a gas-liquid separator, and its control method. The fuel cell system includes a fuel cell, a pump for supplying gas to the fuel cell, a gas-liquid separator for storing a liquid component discharged at least from a cathode side of the fuel cell, a cooler for cooling the stored liquid component, a temperature detector for measuring temperature of liquid component, a liquid level detector for measuring an amount of liquid component, and a controller for controlling a flow rate of gas from the pump and heat discharge by the cooler. The controller controls at least heat discharge by the cooler or a flow rate of gas supplied from the pump based on an output of the temperature detector and an output of the liquid level detector.