Nissan Motor Company Limited

Motohisa Kamijo

Hiroshi Akama

Katsuo Suga

Yasuhisa Kitahara

Yasunari Hanaki

Hiromichi Miwa

Hiroaki Kaneko

Maki Shimada

Takao Izumi

Takashi Aoyama

Tatsuya Yaguchi

Motohiro Shinzawa

Hironori Wakamatsu

Hiroto Kikuchi

Maki Kamikubo

Junji Itou

Hajime Kokusyo

Jyunji Itou

Luc Rouveyre

Tsuguhiro Ohnuma

The present invention comprises a plurality of fuel cells connected to each other in series, and a reformer configured to reform raw fuel, wherein reformed fuel by the reformer is supplied to a first stage of the plurality of fuel cells, and the fuel cell on the first stage is provided with a methane reaction suppressing function which suppresses reaction of methane included in the reformed fuel to a larger extent than at least one fuel cell on a second and later stages. Suppressing temperature drop due to endothermic reaction in the fuel cell on the first stage can improve the efficiency of electric power generation of the fuel cell system having the plurality of fuel cells arranged in series.

Fuel cell system

Disclosed is a fuel cell system which comprises a power generation means that includes a plurality of fuel cells that are connectable to one another in series or in parallel through connecting terminals, a fuel gas supply conduit through which fuel electrodes of all or part of the fuel cells are connected in series and an oxidant gas supply conduit through which air electrodes of all or part of the fuel cells are connected in series; a switching means that switches an electric connection condition between the connecting terminals and connecting means of an external load device; a fuel gas supply means that supplies the fuel gas supply conduit with a fuel gas and an oxidant gas supply means that supplies the oxidant gas supply conduit with an oxidant gas; a load detecting means that detects a load of the external load device; and a control means that selects, based on an already derived relation between overall electric power output curves corresponding to the number of the fuel cells that are mutually connected and an operation temperature zone, one of the power output curves in accordance with an input from the load detecting means and selects the number of mutually connected fuel cells that brings about the highest voltage of the fuel cells thereby to control the switching means, the fuel gas supply means and the oxidant gas supply means.

Fuel cell system and method for controlling same

A fuel reformer includes a reforming element () having at least one reforming catalyst passage () supporting a reforming catalyst which generates reformate gas from fuel; and a combustion element () having at least one combustion gas passage (), which heats the reforming element () by the heat of combustion gas generated by burning the generated reformate gas supplied in air introduced in said at least one combustion gas passage (). The reforming element () and combustion element () are laminated in the fuel reformer. The fuel reformer further includes plural supply holes () arranged in a line along said at least one combustion gas passage (), each supply hole () communicating with said at least one combustion gas passage (). At least part of the generated reformate gas is supplied to each supply hole, and is burnt downstream of each supply hole.

Fuel reformer suppressing uneven temperature distribution in reforming element

A fuel cell system comprises a fuel cell including an anode and cathode, a fuel reformer, and a water gas shift reactor. The fuel cell system is shutdown by shutting down electrical generation and then supplying air to the water gas shift reactor to oxidize CO and Hremaining in the water gas shift reactor after shutdown of electrical generation. The introduction of air to the water gas shift reactor controls CO poisoning of the fuel cell and the emission of flammable and poisonous gases from the fuel cell system after the shutdown of electrical generation.

Fuel processing system and its shutdown procedure

A fuel processing system including a filter for reforming a hydrocarbon fuel and its operation is disclosed. The system includes a first chamber for receiving a hydrocarbon fuel and combining it with air or water; a reformer in fluid connection with and down stream of the first chamber, which receives the hydrocarbon fuel combined with either air or water to reform the fuel to a reformate stream, which contains a hydrogen rich atmosphere; a second chamber in fluid connection with the reformer which is capable of receiving the reformate stream from the reformer; a water inlet connected to the second chamber capable of introducing water to the reformate stream; and a filter in fluid connection with and down stream of the second chamber, which is capable of preventing a substantial portion of any solid particles contained in the reformate stream from passing therethrough. The filter can be regenerated by introducing water as an oxidant to the reformate stream to oxidize any collected soot on the filter in the hydrogen rich atmosphere of the reformate stream.

Fuel processing system for reforming hydrocarbon fuel

An exhaust gas purifying catalyst for purifying exhaust gas discharged from an internal combustion engine of an automotive vehicle. The exhaust gas purifying catalyst comprises a substrate on which a catalytic coat layer containing a catalyst component is formed. The catalytic coat layer is formed by coating a slurry containing the catalyst component on a surface of the substrate. A crack-preventing coat layer is formed on an upper-most surface of the catalytic coat layer. The crack-preventing coat layer has a thickness of not larger than 50 &#x3bc;m.

Exhaust gas purifying catalyst and method of producing same

Hydrogen-rich reformate gas is produced by a fuel reformer () from fuel vapor containing hydrocarbon, which is produced by a fuel vaporizer (), by means of a partial oxidation reaction and a steam reforming reaction. A fuel injector () supplies fuel to the fuel vaporizer (), and an air injector () supplies air to the fuel vaporizer (). A glow plug () partially oxidizes the air-fuel mixture inside the fuel vaporizer (). By controlling the air supply amount in relation to the fuel supply amount to obtain an excess air factor corresponding to a predetermined rich air-fuel ratio, a part of the air-fuel mixture in the fuel vaporizer () is partially oxidized, and the remaining fuel vapor is heated by the oxidation heat. As a result, the partial oxidation reaction and steam reforming reaction in the fuel reformer () are performed with a favorable balance.

Fuel vaporizing device

A fuel reforming system has a reformer () for reforming a fuel to produce a reformate gas; a shift converter () for reacting carbon monoxide (CO) contained in a reformate gas with water to produce hydrogen (H); a CO oxidizer () which removes CO discharged from the shift converter; and a startup combustor () for supplying combustion gas to the reformer (), a shift converter () and CO oxidizer () to warm up them. An NOx trap () is disposed downstream of the startup combustor so as to adsorb nitrogen oxides (NOx) in combustion gas. A fuel reforming system further has a controller for controlling warm-up operations. When the warm-up operation for the reformer, the shift converter and the CO oxidizer is completed, the reformate reactions are commenced in the reformer (). The NOx trapped by the NOx trap is decomposed by the reformate gas which contains CO gas and Hgas.

Fuel reforming system and control therefor

A combustor having a filter used to trap soot generated during its operation that is arranged upstream of a fuel reformer, is disclosed. During a startup period, the combustor functions to regenerate the filter by burning the trapped soot with a lean fuel-air mixture thereby regenerating the filter while continuously heating downstream components.

Startup combustor for a fuel cell

An exhaust gas purifying system for an automotive internal combustion engine. The exhaust gas purifying system comprises a flow-through monolithic catalyst disposed in an exhaust gas passageway through which exhaust gas flows. The monolithic catalyst functions to adsorb and oxidize a soluble organic fraction in exhaust gas, to adsorb nitrogen oxides in exhaust gas in a condition in which a temperature of exhaust gas is not higher than 200&#xb0; C. and to allow carbon particle in exhaust gas to pass through the monolithic catalyst. Additionally, a filter catalyst is disposed in the exhaust gas passageway downstream of the flow-through monolithic catalyst. The filter catalyst functions to trap the carbon particle and to oxidize hydrocarbons, carbon monoxide and nitrogen monoxide in exhaust gas.

Exhaust gas purifying system and method

In order to improve performance of NOx reduction, an additional fuel injection immediately after a main fuel injection is performed. By such additional fuel injection, hydrogen (H ) is supplied to a NOx trap catalyst. And in order to prevent engine output torque from varying by the additional fuel injection, the main fuel injection is controlled by whether the additional fuel injection is performed.

Exhaust gas purification device and method for diesel engine

An exhaust gas purifying system for an internal combustion engine mounted on an automotive vehicle. The exhaust gas purifying system includes an exhaust gas component concentration regulating device disposed in an exhaust gas passageway of the engine, for regulating concentrations of gas components in exhaust gas discharged from the engine such that the concentrations of carbon monoxide and hydrogen are respectively not more than 2.0% by volume and not less than 0.5% by volume and such that a volume concentration ratio of &lsqb;hydrogen/carbon monoxide&rsqb; is not smaller than 0.5, in rich and stoichiometric conditions of exhaust gas. Additionally, a NOx adsorbing and reducing catalyst is disposed in the exhaust gas passageway downstream of the exhaust gas component concentration regulating device, for adsorbing nitrogen oxides in a lean condition of the exhaust gas and reducing the nitrogen oxides into nitrogen in the rich and stoichiometric conditions.

Exhaust gas purifying system

An exhaust gas purifying system for an internal combustion engine mounted on an automotive vehicle. The exhaust gas purifying system may include an exhaust gas component concentration regulating device disposed in an exhaust gas passageway of the engine, for regulating concentrations of gas components in exhaust gas discharged from the engine such that the concentrations of carbon monoxide and hydrogen are respectively not more than 2.0% by volume and not less than 0.5 by volume and such that a volume concentration ratio of hydrogen/carbon monoxide is not smaller than 0.5, in a first exhaust gas condition in which air/fuel ratio of exhaust gas is within a range of from a rich value and a stoichiometric value. Additionally, a NOx adsorbing and reducing catalyst is disposed in the exhaust gas passageway downstream of the exhaust gas component concentration regulating device, for adsorbing nitrogen oxides in a second exhaust gas condition in which the air/fuel ratio of exhaust gas is at a lean value, and reducing the nitrogen oxides into nitrogen in the first exhaust gas condition.

A nitrogen oxide absorbing material ( ) which absorbs nitrogen oxide when the reduction component concentration of exhaust gas in the exhaust passage ( ) of an engine ( ) is lower than a predetermined concentration, and discharges nitrogen oxide when the reduction component concentration of exhaust gas in the exhaust passage ( ) of the engine ( ) is higher than the predetermined concentration, and a catalyst ( ) which promotes reduction of the discharged nitrogen oxides by a reduction component are provided. A controller ( ) first reduces the reduction component concentration of the exhaust gas over a first predetermined time period by, for example, advancing the fuel injection timing. The controller ( ) then increases the reduction component concentration of the exhaust gas over a second predetermined time period by, for example, retarding the fuel injection timing.

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Yokohama, Japan

Motohisa Kamijo