One embodiment is a redox flow battery system that includes an anolyte; a catholyte; an anolyte tank configured for holding at least a portion of the anolyte; a catholyte tank configured for holding at least a portion of the catholyte; a primary redox flow battery arrangement, and a second redox flow battery arrangement. The primary and secondary redox flow battery arrangements share the anolyte and catholyte tanks and each includes a first half-cell including a first electrode in contact with the anolyte, a second half-cell including a second electrode in contact with the catholyte, a separator separating the first half-cell from the second half-cell, an anolyte pump, and a catholyte pump. The peak power delivery capacity of the secondary redox flow battery arrangement is less than the peak power delivery capacity of the primary redox flow battery arrangement.

The present disclosure is directed to a fuel cell module. The fuel cell module may include a fuel cell having an anode, a cathode, and an electrolyte positioned between the anode and the cathode. The fuel cell module may also include an enclosure housing the fuel cell therein. The enclosure may include an air inlet and an air outlet. The fuel cell module may further include an air pressurizing mechanism fluidly connected to the enclosure. The air pressurizing mechanism may be configured to draw air through the air inlet into the enclosure and from the enclosure to the air pressurizing mechanism through the air outlet. The air pressurizing mechanism may be configured to pressurize the air to form a pressurized air stream that is directed to the cathode.

An atmospheric water generator for extracting water droplets from ambient air includes an insulating substrate, a plurality of electrode film units, and a liquid crystal/polymer composite film. Each of surface regions of the liquid crystal/polymer composite film has a plurality of liquid crystal molecules each having a hydrophilic functional group and a hydrophobic moiety. Each of the surface regions normally has one of hydrophilic and hydrophobic properties. When a voltage is applied to one of the electrode film units, the respective surface region is switched to have the other one of hydrophilic and hydrophobic properties, to thereby allow the water droplets condensed from the ambient air to move on the surface regions.

System and method for fuel-cell and motor trend monitoring including recording signals from fuel-cell and motor system-condition sensors or sets of onboard sensors and periodically analyzing results to examine fuel-cell and motor system performance trends to predict the need for fuel-cell or motor system maintenance. Various analyses can be performed, separately or in parallel, including: comparing the current parameter values with recorded parameter values in previous instances of similar operating conditions; comparing parameter values to predetermined nominal ranges; and detecting sensed parameter values that exceed recommended fuel-cell or motor system operating conditions or that exhibit trends over time that if continued result in exceeding fuel-cell or motor system operating conditions or producing out-of-bound readings. Results of the analyses inform fuel-cell, motor, and aircraft system maintenance scheduling and provide alerts to users regarding recommended fuel-cell, motor, and aircraft system performance trends and/or operating condition exceedances, enhancing safety and improving maintenance efficiency.

A voltage converter arrangement for the electrical coupling of a fuel cell unit is provided, which is connected or can be connected on the input side, to a traction network, which is connected or can be connected on the output side, and which comprises a high-voltage battery may comprise a measuring unit for measuring the input voltage supplied by the fuel cell unit, and a comparison unit, which is electrically connected to the measuring unit and is in turn electrically coupled to a controller unit, which is designed to cause the fuel cell unit to be operated at predeterminable operating points, and which is configured to seek time-varying operating points from the fuel cell unit in an impedance operation. A fuel cell system and a method for operating a voltage converter arrangement is also provided.

A redox flow battery system includes an anolyte having a first ionic species in solution; a catholyte having a second ionic species in solution, where the redox flow battery system is configured to reduce the first ionic species in the anolyte and oxidize the second ionic species in the catholyte during charging; a first electrode in contact with the anolyte, where the first electrode includes channels for collection of particles of reduced metallic impurities in the anolyte; a second electrode in contact with the catholyte; and a separator separating the anolyte from the catholyte. A method of reducing metallic impurities in an anolyte of a redox flow battery system includes reducing the metallic impurities in the anolyte; collecting particles of the reduced metallic impurities; and removing the collected particles using a cleaning solution.

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.

A metal air battery includes a first battery cell module which generates electricity by oxidation of a metal and reduction of oxygen, a second battery cell module in fluid-communication with the first battery cell module and which generates electricity by oxidation of a metal and reduction of oxygen, and an air purifier in fluid-communication with the second battery cell module, where the air purifier purifies external air to supply first purified air to the second battery cell module, and the second battery cell module supplies second purified air generated by the oxidation of the metal and the reduction of the oxygen to the first battery cell module.

A direct isopropanol fuel cell adapted for use in ambient conditions and utilizing as fuel isopropanol and water preferably with isopropanol at relatively high concentrations representing 30% to 90% isopropanol.

A fuel cell system that supplies fuel gas and oxidant gas to a fuel cell stack and causes the fuel cell stack to generate power includes a tank that stores aqueous solution containing oxygen-containing fuel, and a reformer that reforms mixed gas obtained as the aqueous solution is vaporized, and generates the fuel gas. The fuel cell system also includes an actuator that supplies the mixed gas to the reformer, a heating device that heats the reformer, a detecting unit that estimates or detects a concentration of the oxygen-containing fuel in the mixed gas that is supplied to the reformer, and a controller programmed to control operations of the actuator and the heating device so that the fuel cell generates power. The controller is programmed to increase a thermal dose to the reformer from the heating device or reduces a supply amount of the mixed gas to the reformer by the actuator when the concentration of the oxygen-containing fuel is high, compared to when the concentration is low.