A fuel cell system and a method for operating the fuel cell system, wherein the fuel cell system includes a fuel cell, a controller, a switch, an oxygen supply device and an output circuit. The fuel cell includes an anode and a cathode. The fuel cell is a cathode enclosed fuel cell. The controller is used to drive control signal for adjusting the electrochemical metering ratio of oxygen flow, supplied by the oxygen supply device, to output current, wherein the electrochemical metering ratio is ‘a’, and ‘a’ satisfies: 1≤a≤4. The method of the present disclosure uses the fuel cell system of the present disclosure, which optimizes the performance of a fuel cell and makes the output interruption time very short; hence it is highly beneficial for providing a more stable output.

A fuel cell system includes a fuel cell stack and a control device. The control device raises the voltage of the fuel cell stack until a predetermined voltage condition is met, by supplying a cathode with an oxidant gas before current sweep is started when the fuel cell system is started and a value measured by a temperature sensor is equal to or less than a temperature determined in advance. The control device executes stand-by control, in which a current command value is kept constant, when a measured voltage value reaches a control start voltage value smaller than a voltage command value in a transition period, and ends the stand-by control by permitting a change in the current command value when the measured voltage value reaches a permission voltage value equal to or more than the voltage command value during execution of the stand-by control.

Provided are method and device for predicting service life and remaining life of a fuel cell. The method includes: activating the fuel cell, obtaining an initial polarization curve of the fuel cell, and selecting a first point having a first current in the initial polarization curve; determining a life end point of the fuel cell according to the initial polarization curve and a decay ratio; obtaining a current polarization curve, and determining a second point having a second current and a same voltage as the first point in the current polarization curve; and determining the service life of the fuel cell according to the first current, the second current, a current relationship between two polarization curves and a service life algorithm of the fuel cell, and obtaining the remaining life of the fuel cell according to the service life and a time of the current polarization curve.

A fuel cell system includes: a first fuel cell; a second fuel cell having a greater maximum power output than the first fuel cell; and a controller configured to cause the first fuel cell to generate greater electric power greater than the second fuel cell when the requested power is smaller than a first threshold, cause the second fuel cell to generate greater electric power than the first fuel cell when the requested power is a second threshold, which is the first threshold or greater and smaller than a third threshold that is greater than the second threshold, is 70% of the maximum power output of the second fuel cell or grater, and is 100% of the maximum power output of the second fuel cell or smaller, and cause both the first and second fuel cells to generate electric power when the requested power is the third threshold or greater.

A fuel cell system includes: a fuel cell; a voltage regulator that regulates an output voltage of the fuel cell; and a controller configured to perform a refresh process of decreasing the output voltage of the fuel cell to a reduction voltage at which an oxide film formed on the cathode is reduced, by controlling the voltage regulator. The controller, before the refresh process, calculates a first amount, the first amount being an amount by which the oxide film is to be removed from the cathode. The controller determines, as the output voltage of the fuel cell, a refresh voltage that enables the first amount of the oxide film to be removed within a preset reference time. The controller operates the voltage regulator so as to cause the output voltage of the fuel cell to become the refresh voltage when the refresh process is performed.

According to one embodiment of the present disclosure, a redox flow battery is provided comprising an ionically conductive separator, a working side flowing electrolyte, a working electrode in ionic contact with the working side of the ionically conductive separator and the working side flowing electrolyte, a counter electrode, and an auxiliary electrode peripherally circumscribed by the working electrode in a common layer of the flow battery. The auxiliary electrode is in ionic contact with the working electrode, an electrically insulating peripheral gap separates the auxiliary electrode from the working electrode. A working electrode terminal is conductively coupled to the working electrode, an auxiliary electrode terminal is conductively coupled to the auxiliary electrode, and a counter electrode terminal is conductively coupled to the counter electrode. An auxiliary power source is configured to establish an auxiliary circuit voltage differential between the counter electrode terminal and the auxiliary electrode terminal, control an auxiliary electrode voltage such that the auxiliary electrode voltage is within an electrochemical window of the working side flowing electrolyte, and establish a voltage differential between the working electrode terminal and the auxiliary electrode terminal. A method of operation of the redox flow battery is further provided.

A voltage is applied between an anode and a cathode in a fuel cell. The voltage is increased to a predetermined upper limit, and then decreased to a predetermined lower limit. The voltage increase and decrease are repeated a predetermined number of times. The voltage is applied to the fuel cell while supplying a hydrogen-containing gas to an anode and supplying an inert gas to a cathode.

The present disclosure provides a method of shortening an aging period of a polymer electrolyte fuel cell immediately after production to increase shipping inspection speed and production speed of the polymer electrolyte fuel cell. The present disclosure relates to an aging method of a fuel cell which comprises a membrane electrode assembly comprising a fuel electrode, an electrolyte membrane, and an oxidant electrode, wherein the method comprises applying a potential cycle, wherein the lowest cell potential when a load is applied and OCV are alternately repeated between the fuel electrode and the oxidant electrode, and in the potential cycle, fuel gas is supplied to the fuel electrode, and oxidant gas and carbon monoxide gas are supplied to the oxidant electrode.

A fuel cell system includes: a fuel cell; a reaction gas supplier which supplies a fuel gas and an oxidizing gas to the fuel cell; a first converter which converts the output voltage of the fuel cell; a secondary battery; a connection line connecting the first converter and the secondary battery in parallel to a load; and a controller. The controller includes a first operation mode and a second operation mode. In the first operation mode, the first converter is operated with a step-up capability that is able to be realized by the first converter. In the second operation mode, the first converter is operated with the maximum step-up capability that is able to be realized by the first converter and in which the reaction gas supplier is used to control the output current of the fuel cell.

An apparatus for sensing voltage information of a fuel cell includes: a sensing unit configured to sense voltages of each cell and all cells included in a fuel cell; a controller configured to control the sensing unit to sense the voltages of each cell and all the cells of the fuel cell according to a command of an upper controller, or to transmit information of the sensed voltages of each cell and all the cells to the upper controller; and the upper controller configured to detect an error cell by calculating output power of the fuel cell based on the information of the voltages received from the controller, to substantially prevent damage to a surrounding cell by stopping an operation of the error cell, and to control the output power in real time in correspondence with a state of the fuel cell.