Nissan Motor Company Limited

Fumio Kagami

Takahiro Fujii

Keigo Ikezoe

Motoharu Obika

Yousuke Tomita

Kazuya Tajiri

Motoharu Obiki

A fuel cell system that supplies fuel gas and oxidant gas to a fuel cell stack and causes the fuel cell stack to generate power includes a tank that stores aqueous solution containing oxygen-containing fuel, and a reformer that reforms mixed gas obtained as the aqueous solution is vaporized, and generates the fuel gas. The fuel cell system also includes an actuator that supplies the mixed gas to the reformer, a heating device that heats the reformer, a detecting unit that estimates or detects a concentration of the oxygen-containing fuel in the mixed gas that is supplied to the reformer, and a controller programmed to control operations of the actuator and the heating device so that the fuel cell generates power. The controller is programmed to increase a thermal dose to the reformer from the heating device or reduces a supply amount of the mixed gas to the reformer by the actuator when the concentration of the oxygen-containing fuel is high, compared to when the concentration is low.

Fuel cell system and method for controlling same

There is provided a fuel cell system having a fuel cell, which determines whether an operating state thereof is a low-temperature-startup operation or a normal-running operation and performs recovery control for increasing a concentration gradient of water in an electrolyte membrane of the fuel cell to be greater than that in the normal-running operation when it is determined that the operating state is the low-temperature-startup operation.

A fuel cell system for generating electric power by supplying an anode gas and a cathode gas to a fuel cell includes: an idle stop unit adapted to stop extraction of a current from the fuel cell in accordance with an operation state of the fuel cell system; and an idle stop recovery unit adapted to restart the extraction of the current from the fuel cell in accordance with the operation state of the fuel cell system. The idle stop recovery unit limits, on the basis of an output voltage of the fuel cell before recovery from idle stop, the current to be extracted from the fuel cell after the recovery from the idle stop.

Fuel cell system

A fuel cell system includes a cathode gas supply unit, a cathode pressure detection unit, a fuel cell temperature detection unit configured to detect a temperature of the fuel cell, an internal resistance detection unit configured to detect an internal resistance of the fuel cell, a target cathode flow rate calculation unit configured to calculate a target cathode flow rate necessary for supply to the fuel cell based on an operating state of the fuel cell system, a cathode flow rate estimation unit configured to estimate a flow rate of the cathode gas according to the pressure of the cathode gas, the temperature of the fuel cell and the internal resistance of the fuel cell, and a cathode flow rate control unit configured to control the cathode gas supply unit based on the target cathode flow rate and the estimated flow rate of the cathode gas.

Provided is a fuel cell system including: a wetness detecting section for detecting a wetness of a fuel cell stack; a target SR setting section for setting a target SR of the fuel cell stack based on the wetness; a smallest SR setting section for setting, based on a load, a smallest SR necessary to prevent flooding of the fuel cell stack; and an SR control section for performing control so that an actual SR becomes temporarily larger than the smallest SR when the target SR is smaller than the smallest SR.

A startup control device of a fuel cell system includes a fuel cell stack having a plurality of fuel cells stacked together, each of the fuel cells having a membrane electrode assembly including an electrolyte membrane interposed between a cathode electrode and an anode electrode. The device further includes a gas supply unit configured to supply a gas to the fuel cell stack and a controller configured to control the gas supply unit based on a parameter value related to the occurrence of flooding of the fuel cell stack. During startup of the fuel cell stack, the gas is supplied to the fuel cell stack at a first supply pressure for a time period determined based on the parameter value, and after the time period has expired, gas is supplied to the fuel cell stack at a second supply pressure, the second supply pressure being less than the first supply pressure.

Startup gas supply pressure control device of fuel cell system

A fuel cell stack is provided having a plurality of unit cells stacked in a horizontal direction. Each unit cell includes an electrolyte membrane having two surfaces and a peripheral edge, electrodes provided on both surfaces of the electrolyte membrane, frame-shaped members provided on both surfaces of the electrolyte membrane adjacent to the respective electrodes and adjacent the peripheral edge of the electrolyte membrane, separators provided on the electrodes and the frame-shaped members and having a reactant gas passage for supplying a reactant gas to each of the electrodes, and a manifold formed in the stacking direction in fluid communication with the reactant gas passage. The manifold includes a horizontal edge portion in fluid communication with the reactant gas passage.

Fuel cell stack

Voltage rising detection unit detects a voltage rising condition of a fuel cell stack after the supply of reactant gas to the fuel cell stack is started. A control unit determines an internal state of the fuel cell stack on the basis of the detected voltage rising condition of the fuel cell stack, and then decides a subsequent operation of the fuel cell stack in accordance with the determination. This makes it possible to minimize deterioration of the fuel cell stack which is caused by generating power continuously in an unsuitable state.

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Yokohama, Japan

Fumio Kagami