Toyota Jidosha Kabushiki Kaisha

Hironori Noto

Kota Manabe

Takashi Yamamoto

Tomoya Ogawa

Katsuki Ishigaki

Masataka Ota

Hiroyuki Imanishi

Yoshiaki Naganuma

Tomotaka Ishikawa

Keigo Suematsu

Hitoshi Hamada

Kimihide Horio

Hideaki Mizuno

Hideki Kubo

Go Tejima

Koichiro Yamashita

Takanao Tomura

A fuel cell system determines whether an operation condition of a fuel cell corresponds to a fuel gas shortage or an oxidation gas shortage. Upon determining that the fuel gas is in shortage, the system sets a lower voltage limit to be higher than that set when the system determines that the oxidation gas is in shortage. The system further controls an output voltage from the fuel cell so as to prevent output voltage from the fuel cell from decreasing below the lower voltage limit.

Fuel cell system

A fuel cell system includes: a fuel cell; a secondary cell that receives and stores surplus power by which output of the fuel cell is greater than power demanded of the system if the output is so, and that compensates for shortfall by which the output of the fuel cell is less than the power demanded of the system if the output is so; a voltage measurement portion that measures voltage of the fuel cell; a current measurement portion that measures current of the fuel cell; and a control portion that performs a control such that the voltage of the fuel cell does not exceed or equal a pre-set high-potential avoidance voltage. If a current-voltage characteristic of the fuel cell declines by at least a pre-determined amount from an early-period level, the control portion re-sets the high-potential avoidance voltage to a value that is smaller than an early-period set value.

Fuel cell system, and control method for fuel cell system

Output voltage of a fuel cellis decreased by a converterto conduct an activation treatment to catalyst of the fuel cell, while measuring reduction current by a current sensorwhile scanning output voltage of the fuel cellover a certain range by the converteras measurement of cyclic voltammetry under the condition that supply of oxidation gas to the fuel cellis stopped from a compressor, and this measurement value is integrated by a control device. The control devicefinds a charge amount of electrode catalyst of the fuel cellbased on this integration value, decides whether this charge amount is smaller or not than a degradation decision value, and displays this decision result on a display. A decision can be made precisely as to whether the electrode catalyst of the fuel cell is degraded or not.

Fuel cell system, electrode catalyst degradation judgment method, and moving body

A fuel cell system includes a fuel cell generating electricity through reaction between fuel and oxidant gases; an air compressor supplying air, as the oxidant gas, to the fuel cell; a shut-off valve interrupting exhaust of air as fuel cell exhaust gas; an air flow meter measuring the flow rate of air supplied to the fuel cell; a pressure sensor measuring a supplied air pressure; and a control unit controlling power generation reaction of the fuel cell, calculating a first calculated air flow rate based on a value measured by the air flow meter and a second calculated air flow rate based on a system volume from the air compressor to the shut-off valve, an air pressure increase in the system volume, calculated based on a value measured by the pressure sensor, and an atmospheric pressure, and calculating a ratio of the second to first calculated air flow rates.

Fuel cell system and control method for fuel cell system

There is disclosed a fuel cell system or the like capable of sufficiently reducing an exhaust hydrogen concentration even in a case where a fuel cell is operated in a state of a low power generation efficiency. A bypass valve is arranged between an oxidation gas supply path and a cathode-off gas channel. In a state in which supply of an oxidation gas to a cathode falls short, pumping hydrogen is included in a cathode-off gas. Therefore, a valve open degree of the bypass valve is regulated, and a flow rate of bypass air is regulated to control the exhaust hydrogen concentration.

Fuel cell system, estimation device of amount of anode gas to be generated and estimation method of amount of anode gas to be generated

A fuel cell system includes: a gas exhaust flow path extended in a stacking direction of laminates and configured to have one end located inside a fuel cell stack and the other end located outside the fuel cell stack; and a water discharge flow path provided at a lower position than the gas exhaust flow path and formed to pass through at least part of the laminates. The gas exhaust flow path is interconnected with the water discharge flow path via at least one connecting section in the fuel cell stack. The gas exhaust flow path includes a narrowed flow path having the smaller sectional area than the sectional area of an adjacent flow path in downstream of the connecting section. The water discharge flow path has a downstream end connecting with the narrowed flow path.

Fuel cell system including gas exhaust and water flow paths and insulator

A fuel cell system capable of restraining temperature change in a fuel cell caused by a refrigerant. The fuel cell system has a refrigerant circulating system for circulating the refrigerant. The refrigerant circulating system has flow control means for restraining the inflow of the refrigerant, which has a predetermined difference in temperature from that of the fuel cell, into the fuel cell.

Disclosed is a fuel cell system capable of restraining a temperature change in a fuel cell caused by a refrigerant. The fuel cell system has a refrigerant circulating system for circulating the refrigerant from the fuel cell to the fuel cell. The refrigerant circulating system has flow control means for restraining the inflow of the refrigerant, which has a predetermined difference in temperature from that of the fuel cell, into the fuel cell.

There is provided a fuel cell system capable of warming up a fuel cell while inhibiting generation of a rush current. A control device switches the connection/disconnection between a fuel cell and a short circuit by a shorting relay. The control device spends, before switching the shorting relay from disconnection to connection during starting at a low temperature, an oxidizing gas remaining in the cathode of the fuel cell by driving auxiliary devices to generate an oxidizing gas-deficient state. Then, the control device switches FC relays from ON to OFF and the shorting relay from OFF to ON to thereby complete the preparation for supplying a short-circuit current.

In a fuel cell system in which a fuel cell case () houses a fuel cell stack () composed of a plurality of cells stacked on top of each other and a cell monitor board () for monitoring cell voltages of the fuel cell stack () and in which the fuel cell stack () is connected to a power converter such as an inverter in order to reduce the influence of the electromagnetic noise from the outside of the circuit board or from the circuit board on the outside and to achieve a stable operation of the fuel cell stack. The cell monitor board () is covered with a cell monitor cover () having high electromagnetic shield property. The cell monitor cover () is made of a conductor such as, for example, copper, iron, or aluminum.

Growing community of inventors

Tokai, Japan

Hironori Noto