A fuel cell system includes a fuel cell a current sensor that detects a current of the fuel cell, a plurality of cell voltage sensors that detects a voltage in a unit of one or two or more cells of the fuel cell among the cells, a pump that adjusts a flow rate of the cooling medium, and a controller. The controller estimates, in a first case, a calorific value of the fuel cell using each detected cell voltage value and the detected current value, decides the flow rate of the cooling medium based on the estimated calorific value, and controls the operation of the pump such that the flow rate of the cooling medium is lower than that of a case where the estimated calorific value is the same in a normal operation of the fuel cell.

A self-powered system and a method for power extraction and measurement of energy-generator units are disclosed. The system comprises an energy generator unit (10) providing an electrical current I.sub.FC and a voltage V.sub.FC; an instrumentation block (20) to measure the electrical current I.sub.FC; and a power management unit (30) connected to the energy generator unit (10) via a first input that collects the electrical current I.sub.FC, extracting an electrical power provided by the energy generator unit (10). The power management unit (30) also has a second input which is connected to a feedback element (40) connected to a voltage reference V.sub.REF, to the voltage V.sub.FC and to the instrumentation block (20). A variation of an equivalent input impedance of the power management unit (30) sets a given parameter of the energy generator unit (10) to a controlled given value and the instrumentation block (20) assists in the control of the parameter.

The invention relates to a device (1) having at least one fuel cell (2) and a DC/DC converter (3) assigned to the latter. A variable voltage generated in the fuel cell (2) is converted, by means of the DC/DC converter (3), into a DC voltage for a system (4) to be supplied. The DC/DC converter (3) is designed to capture internal characteristic variables of the fuel cell (2). Operating states of the fuel cell (2) are captured and/or controlled in dependence on these characteristic variables.

A fuel cell system includes an oxygen-containing gas supply that supplies air to a fuel cell module, a fuel supply that supplies a fuel gas to a fuel cell, a power regulator that regulates supply of a generated current to a load, and a controller. The controller includes a plurality of relational expressions predefined and representing a relationship between a generation current level of the fuel cell and at least one of an air utilization or a fuel utilization, and selects at least one of the plurality of relational expressions based on an increase rate of the current set by the power regulator to increase the generation current level for an independent operation to be performed in, for example, an outage.

The fuel cell system is a fuel cell system wherein, when the amount of power generated by a fuel cell is determined to be equal to or less than a predetermined threshold, a controller issues an intermittent supply command to intermittently supply fuel gas to the fuel cell; wherein the intermittent supply command includes a first intermittent supply command and a second intermittent supply command; wherein the first intermittent supply command increases the flow rate of the fuel gas by setting the opening degree during pressure rise of a linear solenoid valve to relatively more than the second intermittent supply command; and wherein, after the first intermittent supply command, the second intermittent supply command decreases the flow rate of the fuel gas for a predetermined time by setting the opening degree during pressure rise of the linear solenoid valve to relatively less than the first intermittent supply command.

To provide a fuel cell system configured to suppress the occurrence of partial fuel gas deficiency in a fuel cell. A fuel cell system wherein at least one injector selected from the group consisting of a first injector and a second injector is driven by duty ratio control to maintain a fuel gas pressure to the fuel cell within a predetermined range, in accordance with an output current value; wherein a controller determines whether or not the output current value is larger than a predetermined first threshold; and wherein, when the controller determines that the output current value is larger than the predetermined first threshold, the controller drives the first injector by duty ratio control, and the controller drives the second injector by duty ratio control to open a valve of the second injector at least while a valve of the first injector is closed.

A fuel cell system includes first and second fuel cells, first and second coolers cooling coolant, first and second coolant supply path from the coolers to the fuel cells, first and second coolant discharge paths from the fuel cells to the coolers, a detour path connecting the first coolant supply path and the first coolant discharge path bypassing the first cooler, an adjusting device adjusting a flow rate of coolant of the detour path, first and second connection paths connecting the coolant supply paths and the coolant discharge paths, first and second opening/closing valves in the connection paths, and a controller configured to, when there is a possibility of flooding, suspend power generation of the first fuel cell and control the adjusting device or the first cooling device such that a temperature of the coolant of the first fuel cell increases, and open the opening/closing valves.

A unit cell for a fuel cell stack including an anode catalyst layer separated by a polymer electrolyte membrane from a cathode catalyst layer, a first cell end plate separated by a first gas diffusion layer from the anode catalyst layer, and a second cell end plate separated by a second gas diffusion layer from the cathode catalyst layer, wherein the first cell end plate, the second cell end plate, or both include a matrix of electrically-conducting protrusions thereof.

The present disclosure provides a flow battery module for improving energy efficiency of flow battery during dynamic load conditions. The flow battery module comprises a plurality of stacks connected in any or a combination of parallel and series. One or more pumps are configured to circulate electrolyte to the stack where ion exchange between the electrolyte occurs and a current is generated. A series of switches are configured between the flow battery and an external load or source. Based on the load or charging power stacks can be electrically and fluidically isolated thereby decreasing parasitic power consumption and self-discharge current, and as a result improving energy efficiency

A method of predicting a life of a membrane electrode assembly (MEA) of a fuel cell for electric power generation includes: deriving an operating condition for accelerated degradation, which is applicable to the fuel cell; operating the fuel cell for a specific time under the derived operating condition for accelerated degradation and under a normal operating condition, and identifying the degree of degradation of the fuel cell under each of the operating conditions; calculating an acceleration multiple based on the degree of degradation identified under the operating condition for accelerated degradation and under the normal operating condition; and predicting the life of the membrane electrode assembly based on the acceleration multiple.