A electrochemical battery including: a battery module including one or more metal air cells which use oxygen gas as a positive electrode active material; an air supply configured to supply air to the battery module and to adjust an oxygen concentration in air supplied to the battery module; and a control unit configured to control an oxygen concentration adjusting operation of the air supply unit. Also a method of operating the electrochemical battery including: supplying air to a battery module using an air supply unit, the battery module including one or more metal air cells which use oxygen in air as a positive electrode active material; and controlling the air supply unit to adjust an oxygen concentration in the air supplied to the battery module.

Disclosed are a safety system of a fuel cell vehicle and a control method for the safety system. A safety system of a fuel cell vehicle using a fuel cell and a high voltage battery as a power source may include: a power switch disposed on a power wire connecting the power source and a power load to each other; an insulation resistance measuring device measuring an insulation resistance between the power wire and a chassis; and a controller controlling an operation of the power switch based on a measured insulation resistance measured by the insulation resistance measuring device. When the measured insulation resistance is equal to or less than a reference resistance, the controller enters a safe mode and the power switch is turned off to thereby block power supplied to the power load.

A power conditioning system includes a fuel cell connected to a load, a fuel cell converter connected between the fuel cell and the load and converting an output voltage of the fuel cell at a predetermined required voltage ratio, and a battery connected to the load in parallel to the fuel cell and serving as a power supply source different from the fuel cell. The power conditioning system includes an impedance measuring device configured to measure an impedance of the fuel cell by outputting alternating currents between a positive electrode and an intermediate point of the fuel cell and between the intermediate point and a negative electrode of the fuel cell, and a current bypass path configured to couple the fuel cell and the load while bypassing the fuel cell converter. The power conditioning system includes a current cut-off unit configured to provide on the current bypass path, the current cut-off unit electrically cutting off the current bypass path when the impedance of the fuel cell is measured by the impedance measuring device.

A power conditioning system includes a fuel cell connected to a load, a fuel cell converter connected between the fuel cell and the load and converting an output voltage of the fuel cell at a predetermined required voltage ratio, a battery connected to the load in parallel to the fuel cell and serving as a power supply source different from the fuel cell, and a battery converter connected between the battery and the load and converting an output voltage of the battery at a predetermined required voltage ratio. The power conditioning system includes a current bypass path configured to couple the fuel cell and the load while bypassing the fuel cell converter, an alternating-current voltage application unit configured to apply an alternating-current voltage signal to an output side of the fuel cell converter, and an internal state estimation unit configured to estimate an internal state of the fuel cell on the basis of a predetermined physical quantity when the alternating-current voltage signal was applied by the alternating-current voltage application unit.

A state determination device for a fuel cell for generating power upon receiving the supply of anode gas and cathode gas, comprising: an internal impedance measurement unit configured to measure an internal impedance of the fuel cell on the basis of an alternating-current signal of a predetermined frequency output from the fuel cell; and an anode reaction resistance estimation/calculation unit configured to calculate an estimation value of a reaction resistance of an anode electrode of the fuel cell on the basis of a measurement value of the internal impedance, wherein: the predetermined frequency is selected such that a difference between the estimation value of the reaction resistance of the anode electrode during hydrogen starvation and the estimation value of the reaction resistance of the anode electrode during oxygen starvation is not smaller than a predetermined value.

A state detection device for fuel cell includes a supposed high-frequency impedance value setting unit configured to set a supposed high-frequency impedance value on the basis of an impedance measurement value belonging to an arc region of an impedance curve of the fuel cell, an actually measured high-frequency impedance value calculation unit configured to obtain an actually measured high-frequency impedance value on the basis of an impedance measurement value belonging to a non-arc region of the impedance curve of the fuel cell, and an ionomer resistance estimation unit configured to estimate a value obtained by subtracting the actually measured high-frequency impedance value from the supposed high-frequency impedance value as an ionomer resistance value. The supposed high-frequency impedance value setting unit sets a value of an intersection of an equivalent circuit impedance curve set on the basis of the impedance measurement value belonging to the arc region and a real ads as the supposed high-frequency impedance value.

An integrated DC/DC converter includes a first DC/DC converter, a second DC/DC converter, a first voltage sensor, a second voltage sensor, a first current sensor, a second current sensor, a third current sensor, and a controller. The first DC/DC converter has an input end and an output end. The input end of the first DC/DC converter is to be electrically connected to an output end of an electrochemical energy storage apparatus. The output end of the first DC/DC converter is to be electrically connected to an input end of an electrical load. The second DC/DC converter connects the first DC/DC converter in parallel.

A fuel cell internal state detection system includes estimation object state quantity setting unit for setting a suitable estimation object state quantity as an index of an internal state, an impedance value acquisition unit configured to obtain an impedance value of a fuel cell, an impedance usability judging unit configured to judge whether or not the obtained impedance value is usable for the calculation of the estimation object state quantity, estimation object state quantity calculation unit for calculating the estimation object state quantity set by the estimation object state quantity setting unit on the basis of the obtained impedance value when the impedance value is judged to be usable for the calculation of the estimation object state quantity by the impedance usability judging unit, and an unusable-scene process execution unit configured to perform an unusable-scene process when the impedance value is judged not to be usable for the calculation of the estimation object state quantity by the impedance usability judging unit.

A fuel cell system, comprising: a fuel cell stack including a stacked body provided by stacking a plurality of cells in a stacking direction; a compressor configured to feed a purge gas to a cathode of the fuel cell stack; a controller configured to control the compressor, such as to perform stop-time purging that purges the cathode of the fuel cell stack when operation of the fuel cell system is stopped; a first temperature gauge configured to measure a first temperature value that reflects temperature of a cell placed near a center in the stacking direction among the plurality of cells constituting the stacked body and to input the measured first temperature value into the controller; and a second temperature gauge configured to measure a second temperature value that reflects temperature of a cell placed near an end in the stacking direction among the plurality of cells constituting the stacked body and to input the measured second temperature value into the controller, wherein the controller is configured to suspend the stop-time purging when the first temperature value is equal to or higher than a first reference temperature and the second temperature value is lower than a second reference temperature.

A power supply device for the electrical power supply of at least one consumer has a primary power grid, in which a fuel cell device is present, having a secondary power grid, in which a battery is present, having an operating voltage range bounded at the top by a maximum voltage and at the bottom by a minimum voltage, and having an operating current strength range for powering the at least one consumer. An open circuit voltage of the fuel cell device corresponds at most to the maximum voltage of the battery, while there is present in the primary power grid an impedance spectroscopy device, which is designed to perform an impedance spectroscopy measurement on the fuel cell device or on individual fuel cells of the fuel cell device. A fuel cell vehicle has such a power supply device and a method for starting a power supply device.