A redox flow battery operation method that performs charge and discharge by circulating an electrolyte between a tank and a first battery cell, the method includes a main process performing the charge at a current density greater than or equal to 250 mA/cm.sup.2.

Ce and Zn doped NiFe2O.sub.4 materials synthesized via a sol-gel method used as a catalyst. The NiFe.sub.2O.sub.4 catalysts doped with Ce and Zn exhibit distinctive electrocatalytic activity towards urea oxidation. The Ce and Zn-doped NiFe.sub.2O.sub.4 catalysts can play a critical role as catalytic moderators, accelerating charge transfer in the anodic part of the urea fuel cell (UFC) and potentially improving the efficiency and cost of UFCs. These materials provide a promising approach for developing novel, non-precious electrodes for next-generation fuel technologies.

A vehicle includes an electric machine, a battery, an inverter, and a controller. The controller switches the inverter at a switching frequency selected to generate an AC current to heat the battery, adjusts a d-axis current of the electric machine to increase a battery heating power, and adjusts a q-axis current of the electric machine according to the adjusted d-axis current.

A fuel cell electric vehicle (FCEV) power control system reduces a power limitation in conditions such as uphill driving and/or high temperature environments. The FCEV power control system utilizes dynamic cooling detection logic and/or predictive convection. The FCEV power control system may be operated in accordance with a method of controlling power of a fuel cell including receiving a plurality of inputs including a heat output of the fuel cell, an ambient temperature, a temperature of a coolant of the fuel cell, and a time of operation of the fuel cell. The method may include calculating an accumulation of cooling from convection, an accumulation of heat generated from the fuel cell, and a cooling ratio. The method may include adjusting a maximum allowable current of the fuel cell based on the cooling ratio. Related apparatuses, systems, techniques and articles are also described.

To provide a fuel cell system capable of evaluating degradation of an electrolyte membrane by quantifying metal ions involved in degradation of an electrolyte membrane instead of evaluating degradation of an electrolyte membrane itself. A fuel cell system comprising a fuel cell, a fuel gas system for supplying fuel gas to an anode of the fuel cell, an oxidant gas system for supplying oxidant gas to a cathode of the fuel cell, a voltage detector for detecting a voltage of the fuel cell, and a controller.

An elevated target amount of electrolyte is used to initially fill a molten carbonate fuel cell that is operated under carbon capture conditions. The increased target electrolyte fill level can be achieved in part by adding additional electrolyte to the cathode collector prior to start of operation. The increased target electrolyte fill level can provide improved fuel cell performance and lifetime when operating a molten carbonate fuel cell at high current density with a low-CO.sub.2 content cathode input stream and/or when operating a molten carbonate fuel cell at high CO.sub.2 utilization.

A method for detecting leakage of a reducing fluid throughout an electrolyte membrane of an electrochemical cell is provided. The method includes the following consecutive steps: supplying the cell with anode and cathode streams; brisk and controlled variation of at least one of the following parameters: the pressure of the anode stream in the anode channel, the pressure of the cathode stream in the cathode channel, the flow rate of the anode stream into the anode channel, the flow rate of the cathode stream into the cathode channel, and the strength of the current exchanged between the two sides of the membrane; measurement of a first reducing fluid concentration in a first stream, including the cathode stream leaving the cathode channel; and deducing the presence or absence of leakage on the basis of the variation in the first measured concentration of reducing fluid over time. A corresponding fuel cell system is also provided.

Systems and methods for managing flow batteries utilize a battery management controller (BMC) coupled between a flow battery and a DC/DC converter, which is coupled to an electrical grid or a photovoltaic device via an inverter. The inverter converts an AC voltage to a first DC voltage and the DC/DC converter steps down the first DC voltage to a second DC voltage. The BMC includes a first power route, a second power route, and a current source converter coupled to the second power route. The BMC initializes the flow battery with a third DC voltage using the current source converter until a sensing circuit senses that the voltage of the flow battery has reached a predetermined voltage. The sensing circuit may include a capacitor, which has a small capacitance and is coupled across each cell of the flow battery, coupled in series between two resistors having very large resistances.

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 vehicle according to the present disclosure includes: a fuel cell; a multiphase converter configured to control an output current of the fuel cell; a current sensor provided in each phase of the multiphase converter; an electric load configured to receive power supplied from the fuel cell; and a control unit. The control unit performs, when it detects an excess or a deficiency of electric energy of the electric load, replacement of phases driven by the multiphase converter while the output current of the fuel cell is kept constant, and determines, when the excess or the deficiency of the electric energy of the electric load is eliminated after the replacement of the phases, that an offset failure has occurred in the current sensor provided in the phase that has been driven before the replacement.