A control method for a fuel cell system with a gas supplying device configured to supply fuel gas and oxidant gas to a fuel cell, includes a power generating operation step of performing a power generating operation for causing the fuel cell to generate power by controlling the fuel gas and the oxidant gas to be supplied to the fuel cell on the basis of a load required of the fuel cell. Further, the control method includes an autonomous operation step of performing an autonomous operation of the fuel cell when the load drops to or below a predetermined value. In the autonomous operation, power supply from the fuel cell system to the load is stopped and the fuel gas is passed to an anode of the fuel cell.

A battery system control device includes a load, a secondary battery connected to the load via a first power converter converting a voltage by a switching operation, a fuel cell, and a control unit. The battery discharges power supplied to the load. The fuel cell is connected to the load and to the battery and the first power converter, via a second power converter converting a voltage. The fuel cell generates low voltage power. The control unit charges the battery using the generated power from the fuel cell. The control unit includes fuel cell and secondary battery controllers. The fuel cell controller steps up the power generated by the fuel cell to a voltage chargeable by the battery to be supplied to the load by the second power converter. The secondary battery controller directly connects the load and the battery by stopping the switching operation of the first power converter.

The disclosed embodiments relate to the design of a portable and cost-effective fuel cell system for a portable computing device. This fuel cell system includes a fuel cell stack which converts fuel into electrical power. It also includes a fuel source for the fuel cell stack and a controller which controls operation of the fuel cell system. The fuel system also includes an interface to the portable computing device, wherein the interface comprises a power link that provides power to the portable computing device, and a bidirectional communication link that provides bidirectional communication between the portable computing device and the controller for the fuel cell system.

A fuel cell stack includes a cell stack body including a plurality of stacked power generation cells together. A metal plate and an elastic seal member are overlapped with each other at a position facing a bead seal formed on an end metal separator. A support member includes a recess accommodating the metal plate. A gap is provided between an inner peripheral end of the metal plate and the recess, or between an outer peripheral end of the metal plate and the recess, for absorbing thermal expansion difference between the metal plate and the support member.

A fuel cell system configured to supply electric power to load includes: a fuel cell; and a control unit configured to set target electric power to be generated by the fuel cell and control electric power generation by the fuel cell such that the fuel cell generates the target electric power. The control unit is configured to, when setting the target electric power using request electric power that the load requests the fuel cell to generate, execute a fluctuation suppression process for making a fluctuation of the target electric power smaller than a fluctuation of the request electric power.

A Reversible Solid Oxide Fuel Cell (RSOFC) system includes a Reversible Solid Oxide Fuel Cell (RSOFC) unit, a bi-directional alternating current/direct current (AC/DC) converter, coupled to the RSOFC unit, a common bus, coupled to the bi-directional AC/DC converter and to a power grid, and a plurality of RSOFC subsystems, coupled to receive power only through the common bus. The RSOFC unit has a fuel cell mode, wherein the RSOFC unit produces electrical power from fuel, and an electrolysis mode, wherein the RSOFC unit consumes electrical power to produce the fuel. The bi-directional AC/DC converter is coupled to the RSOFC unit, and is configured to convert direct current (DC) electrical power produced by the RSOFC unit into outgoing alternating current (AC) power, and to convert incoming AC power into DC power for consumption by the RSOFC unit in electrolysis mode.

A fuel cell device is improved for operating conditions during a partial load operation. The fuel cell device comprises a cell stack formed by electrically connecting fuel cells for generating power by fuel gas and oxygen-containing gas; a fuel gas supply unit for supplying the fuel gas to the fuel cells; and a power adjustment unit for adjusting the amount of current that is supplied to an external load and a controller for controlling the fuel gas supply unit and the power adjustment unit. The controller adjusts, during the partial load operation of the fuel cell device and when the fuel gas supplied to the cell stack is at a low flow rate. The relationship between a fuel utilization rate of the cell stack and the amount of power generated by the cell stack can be nonlinear.

When electric power requested from a load exceeds a predetermined reference value, an operating state of the fuel cell system is controlled so as to enable a normal operation mode where the fuel cell generates electric power corresponding to the requested electric power. When the requested electric power is the reference value or less, the operating state is controlled to enable an intermittent operation mode. A refresh process for sweeping current from the fuel cell and lowering the voltage of the fuel cell to a reduction voltage is executed during a shift from the intermittent operation mode to the normal operation mode. The current swept from the fuel cell at the start of the refresh process is reduced more as an oxygen amount in the fuel cell at the end of the intermittent operation mode is smaller.

A method for power control of a fuel cell system in a vehicle is disclosed. The requested fuel cell system power by the vehicle is converted into a power request made of the fuel cell by an expected power of auxiliary drives of the fuel cell system at the requested fuel cell system power being added to the requested fuel cell system power. A media supply of the fuel cell which corresponds to the power request made of the fuel cell is requested. The electrical loading of the fuel cell with current is performed in accordance with a model of the cathode dynamics such that a control variable of the control operation is matched to the media dynamics, and the power release is performed such that the fuel cell is loaded only when the adequate media supply is ensured.

Disclosed is a fuel cell system that stops producing electricity and exhausts residual electricity in an emergency situation. The fuel cell system includes a stack receiving a reactive gas including a hydrogen and/or an oxygen to produce the electricity, a pump supplying the reactive gas to the stack, a discharge circuit including a resistor that discharges a residual power in the stack and a first relay that electrically connects or disconnects the resistor to or from the stack, a generator connected to a rotational shaft of the pump to convert a driving energy of the rotational shaft of the pump to an electric energy, and a first controller controlling the first relay. The first controller receives the electric energy from the generator and controls the first relay to electrically connect the stack and the resistor such that the residual electricity in the stack is exhausted in the emergency situation.