Toyota Jidosha Kabushiki Kaisha

Hideyuki Kumei

Tomohiko Kaneko

Masayuki Ito

Manabu Kato

Shuya Kawahara

Satoshi Watanabe

Kohei Oda

Yoshiaki Tsuruta

Masato Nakajima

Tsuyoshi Maruo

Kazutaka Kimura

Tomoaki Uchiyama

Norihiko Haraikawa

Michihito Tanaka

Hiromichi Satou

A fuel cell system includes a first fuel cell stack having a discharge manifold, a second fuel cell stack having a discharge manifold, a first auxiliary machine used for power generation of the first fuel cell stack, a second auxiliary machine used for power generation of the second fuel cell stack, and a controller configured to control operation of the first auxiliary machine and the second auxiliary machine. The controller is configured to control operation of the first auxiliary machine and the second auxiliary machine, such that one of the first fuel cell stack and the second fuel cell stack, of which a discharge direction of reaction gas discharged from the discharge manifold forms a smaller angle with a vertical downward direction, starts generating power earlier than the other fuel cell stack, after power generation of the first fuel cell stack and the second fuel cell stack is stopped.

Fuel cell system

A fuel cell system includes: a fuel cell unit; first and second supply systems; a switching device; a switching control unit, when required power of the fuel cell unit is equal to or smaller than a threshold; an open circuit voltage obtaining unit; and a supply system control unit.

A fuel cell system includes: first and second injectors; first and second ejectors; a first circulation passage configured to circulate anode gas that has passed the first ejector between the first fuel cell and the first ejector; a second circulation passage configured to circulate the anode gas that has passed the second ejector between the second fuel cell and the second ejector; a communication passage communicating with the first and second circulation passages; a switching valve configured to switch the communication passage to a communication state where the first and second circulation passages communicate with each other or to a cutoff state where the first and second circulation passages are cut off; and a controller configured to scavenge the first fuel cell by injecting the anode gas with the first injector, while the first fuel cell stops power generation in the communication state.

A fuel cell system includes a fuel cell, a supply device configured to supply a cathode gas to the fuel cell; and a control unit configured to execute recovery processing of causing a catalyst of the fuel cell to recover from performance deterioration by lowering an output voltage of the fuel cell. The control unit is configured to, when the recovery processing that has been executed is completed, control the supply device to place the fuel cell in a power generation paused state while making a stoichiometric ratio of the cathode gas lower than a stoichiometric ratio of the cathode gas in a normal operation state that is a state before execution of the recovery processing.

A fuel cell system includes: a fuel cell unit; first and second supply systems; a switching device; a switching control unit; an open circuit voltage obtaining unit; and a supply system control unit.

A fuel cell system includes: a secondary battery; first and second fuel cells; first and second scavenging devices configured to scavenge the first and second fuel cells, respectively; and a control device configured to perform a first scavenging process of scavenging the first fuel cell by driving the first scavenging device using a charged power of the secondary battery when the first and second fuel cells are in a power generation stopped state and to perform a second scavenging process of scavenging the second fuel cell by driving the second scavenging device using a generated power of the first fuel cell when the first fuel cell is in a power generation state and the second fuel cell is in the power generation stopped state.

A fuel cell system according to one embodiment performs refresh control of an electrode catalyst of a fuel cell, by reducing a stack voltage as a voltage of the fuel cell to a refresh voltage at which the electrode catalyst is activated. The system includes the fuel cell that generates electric power by an electrochemical reaction using fuel gas and oxidation gas, a stack voltage sensor that sensors the stack voltage, and a controller that controls power of the fuel cell. When a high load demand that makes the stack voltage lower than a given voltage is made on the fuel cell, the controller causes the fuel cell to deliver power commensurate with the high load demand, and performs refresh control when the stack voltage becomes lower than the given voltage through the above control.

A fuel cell system comprising: a fuel cell stack including: a stacked body in which unit cells are stacked, the unit cells including first and second unit cells; a reactant gas flow path; and a cooling water flow path; a pump that supplies cooling water to the cooling water flow path; a supply device that supplies reactant gas to the reactant gas flow path; and a control device configured to include: a bubble detection portion configured to detect an accumulation of bubbles in the cooling water flow path; and a cause determination portion configured to determine whether or not the accumulation of bubbles is caused by leakage of the reactant gas from the reactant gas flow path, when the bubble detection portion detects the accumulation of bubbles.

A fuel cell system of the present disclosure performs a first and a second catalyst activation process, and the first catalyst activation process is performed where a flow rate of the air supplied to the fuel cell by the air compressor is reduced to be less than that before the refresh control is performed while keeping an amount of a current drawn from the fuel cell by the fuel cell converter at the same value as that before the refresh control is performed, and the second catalyst activation process is performed where the value of the current drawn from the fuel cell by the fuel cell converter is increased to be greater than that before the refresh control is performed while keeping the flow rate of the air supplied to the fuel cell by the air compressor at the same value as that before the refresh control is performed.

A fuel cell comprises: a membrane electrode assembly configured to have an electrolyte membrane joined between an anode electrode and a cathode electrode; a flow path-forming member configured to form a flow path that is adjacent to one electrode out of the anode electrode and the cathode electrode and makes a flow of a reactive gas to the one electrode; and a plate-like member made of a material of blocking the reactive gas and stacked on a portion of a flow path-side surface of the one electrode to be adjacent to the flow path. The plate-like member has a gas permeation structure allowing for permeation of the reactive gas in a part where the anode electrode and the cathode electrode are placed in a stacking direction of the plate-like member on the one electrode.

Fuel cell

A fuel cell system and a control method therefor are provided. The fuel cell system includes: a fuel cell formed of a plurality of stacked power generating elements; a cell voltage measuring unit detecting negative voltage in any one of the power generating elements; a control unit controlling electric power output from the fuel cell; and an accumulated current value measuring unit measuring an accumulated current value obtained by time integration of current output from the fuel cell. The control unit prestores a correlation between accumulated current values and current densities that are allowable for the fuel cell in a period during which negative voltage is generated. When negative voltage has been detected, the control unit executes output restricting process of restricting electric power output from the fuel cell so as to fall within an operation allowable range defined by the accumulated current values and current densities of the correlation.

Methods and systems for controlling power output of a fuel cell

A fuel cell system has a fuel cell that includes at least one cell with an electrolyte membrane, an index value acquirer and a controller. The index value acquirer obtains a temperature index value correlated to temperature of a short circuit area in each cell. The controller controls a control parameter of the fuel cell affecting the temperature of the short circuit area, such that the temperature index value is within a predetermined range set to make the temperature of the short circuit area lower than a decomposition temperature of the electrolyte membrane.

Controlling fuel cell

In a fuel cell system, a controller is programmed to control a first gas supply mechanism to deliver a first gas containing a fuel gas to a cathode in a pre-stop process performed at a system stop of the fuel cell system. The controller is programmed to control the first gas supply mechanism to stop the delivery of the first gas in a first state where a partial pressure difference between an anode and the cathode with respect to at least the fuel gas of remaining gases in the anode and in the cathode is reduced to or below a preset reference value.

Fuel cell system and method of stopping fuel cell system

An IR resistance of each of unit cells is measured, and a highest unit cell voltage as a threshold voltage is set based on the IR resistance and load current. The setting of the highest unit cell voltage uses map data that approximates current-voltage characteristics of a unit cell when the fuel gas is insufficiently supplied. In that case, the highest unit cell voltage is determined based on the voltage with respect to the load current obtained from the map data, and the IR loss calculated from the IR resistance and the load current. This highest unit cell voltage is compared with the measured unit cell voltage. If the unit cell voltage is below the highest unit cell voltage, the power generation of the fuel cell is stopped or restrained.

A fuel cell system includes a fuel cell; a cathode inflow water amount determining portion that determines a cathode inflow water amount after activation of the fuel cell; an obtaining portion that obtains a pore total volume of the cathode side catalyst layer; an operating condition determining portion that determines, based on the determined cathode inflow water amount and the obtained pore total volume, an operating condition of the fuel cell that includes a current value of current that flows through the fuel cell and an upper limit value of a period of time for which the current flows, for bringing the cathode inflow water amount within a range that is equal to or less than the pore total volume; and an adjusting portion that adjusts the current value and the period of time for which current of the current value flows, such that the determined operating condition is realized.

Growing community of inventors

Sunto-gun, Japan

Hideyuki Kumei