Disclosed is a method and a device configured to control deterioration avoidance operation of a fuel cell system. In one aspect, the method may include starting the deterioration avoidance operation when an operation of a fuel cell is restarted in a state where an energy storage device is operating, and the fuel cell is stopped; controlling anode hydrogen pressure based on a predetermined condition, the condition indicating that the anode hydrogen pressure needs to be increased; determining hydrogen recirculation and supplying hydrogen including a process to determine whether to recirculate hydrogen based on a predetermined condition, the condition indicating that hydrogen needs to be recirculated, before supplying hydrogen; determining air recirculation and supplying air including a process to determine whether to recirculate air based on a predetermined condition, the condition indicating that air needs to be recirculated, before supplying air; and terminating the deterioration avoidance operation and starting operation of the fuel cell.

The subject matter of this specification can be embodied in, among other things, a hydrogen fuel cell anode control system including a hydrogen inlet configured to receive pressurized hydrogen, a hydrogen outlet configured to be fluidically coupled to an anode manifold of a hydrogen fuel cell, a recirculation inlet configured to receive overflow hydrogen from the anode manifold, a hydrogen pressure regulator configured to receive pressurized hydrogen from the hydrogen inlet, a hydrogen recirculation module configured to mix hydrogen received from the hydrogen pressure regulator and the recirculation inlet, and provide a hydrogen mixture to the hydrogen outlet, a differential pressure measurement module configured to measure a differential pressure between the anode manifold and a cathode manifold of the hydrogen fuel cell, and a controller configured to control at least one of the hydrogen pressure regulator or the hydrogen recirculation module based on the measured differential pressure.

Systems and methods for operating an electric energy storage device are described. The systems and methods may generate a state of charge estimate that is based on negative electrode plating. An overall state of charge may be determined from the state of charge estimate that is based on negative electrode plating and a state of charge estimate that is not based on negative electrode plating.

A fuel cell system includes a fuel cell generating electric power by a reaction between a fuel gas and an oxidant gas, an injector supplying the fuel gas to the fuel cell, a discharge line in which an off-gas discharged from the fuel cell flows, an ejector recirculating the off-gas flowing in the discharge line to the fuel cell using a flow of the fuel gas from the injector, a discharge valve discharging the off-gas flowing in the discharge line to the outside, and a control device controlling supply of the fuel gas by the injector and opening and closing of the discharge valve. When supply of the fuel gas by the injector is stopped, the control device opens the discharge valve while the off-gas is recirculated to the fuel cell and closes the discharge valve before supply of the fuel gas by the injector is restarted.

A state detection device for a fuel cell for generating power upon receiving a supply of anode gas and cathode gas, including an impedance acquisition unit configured to acquire a high frequency impedance based on a frequency selected from a high frequency band and a low frequency impedance based on a frequency selected from a low frequency band, the high frequency band including a frequency band which shows responsiveness at least to a state quantity of an anode electrode, the low frequency band including a frequency band which shows responsiveness at least to a state quantity of a cathode electrode, and an internal state quantity estimation unit configured to estimate each of the state quantity of the anode electrode and the state quantity of the cathode electrode by combining the acquired high frequency impedance and low frequency impedance, the state quantity of the anode electrode and the state quantity of the cathode electrode serving as internal states of the fuel cell.

A method of operating a fuel cell assembly comprising a plurality of fuel cells connected together for collectively providing power to a load, each fuel cell including an anode and a cathode, the method comprising selectively providing an electrical connection between the anode and the cathode of at least one of the fuel cells of the assembly for lowering the voltage across the fuel cell independent of the load.

A method for calculating voltage loss of a fuel cell is provided. The method includes sensing an open circuit voltage that is generated in a stack when the switch is opened and detecting an operation voltage and an operation current that are generated in the stack when the switch is closed. A first change graph of voltage data over time is calculated using the voltage data and current data from a time when the switch is opened in a state where the switch is closed. A first voltage of a point at which a trend line for an interval where the voltage data linearly varies with the time meets the first change graph is sensed and then an ohmic resistance voltage loss is calculated using a difference between the first voltage and the operation voltage.

A method of shutting down a fuel cell system includes a fuel cell includes generating power via an electrochemical reaction between a fuel gas and an oxidant gas. A shutdown command is output to the fuel cell to stop generating power. The fuel cell is controlled to continue generating power during an oxygen consumption process to consume oxygen in the oxidant gas remaining in a cathode system of the fuel cell even when the shutdown command is output to the fuel cell. At least one of voltage, current, and power output from the fuel cell is detected during the oxygen consumption process. Whether an abnormality occurs during the oxygen consumption process is determined based on at least one of the voltage, the current, and the power. The fuel cell is controlled to stop generating power during the oxygen consumption process when it is determined that abnormality occurs.

The present disclosure generally relates to systems and methods for purging water or gas from a fuel cell system. The fuel cell system may include a multi-phase valve system and/or a separate valve system. The opening and closing of the valve systems for removing gas and water is controlled by a controller,

A system and method for controlling power for a fuel cell are disclosed. The system includes: a fuel cell; a load device electrically connected to the fuel cell; a stack controller configured to set a stack limit current on the basis of a current output current of the fuel cell, the stack limit current configured to limit an output current of the fuel cell on the basis of an output voltage of the fuel cell; and a load controller configured to set a consumption limit current on the basis of the set stack limit current, the consumption limit current configured to limit a consumption current of the load device, the load controller being configured to control the consumption current of the load device to a value equal to or lower than the set consumption limit current.