A cooling system is provided for use with a fuel cell. The cooling system comprises a first heat exchanger fluidly connected to an outlet passage of the fuel cell. The first heat exchanger can be configured to condense at least a portion of a fluid passing through the outlet passage of the fuel cell into liquid water. The cooling system can also comprise a second heat exchanger fluidly connected to an outlet passage of the first heat exchanger and an inlet passage of the fuel cell. The second heat exchanger can be configured to cool a fluid passing into the inlet passage of the fuel cell. In addition, the outlet passage of the fuel cell and the inlet passage of the fuel cell can be fluidly connected to a cathode of the fuel cell, and the inlet passage of the fuel cell can be configured to supply water to the cathode.

A fuel cell oxygen delivery system, method, and apparatus for full-scale clean fuel electric-powered vehicle having a fuel cell module including a plurality of fuel cells working together that augments gaseous oxygen from ambient air and gaseous hydrogen extracted from liquid hydrogen by pressure change or heat exchangers, with fuel cells containing electrical circuits configured to collect electrons from the plurality of hydrogen fuel cells to supply voltage and current to motor controllers commanded by control units configured to control an amount and distribution of electrical voltage and torque or current for each of one or more motor and propeller or rotor assembly, wherein electrons returning from the electrical circuits combine with both oxygen derived from air and onboard oxygen from the delivery system to form oxygen ions, then protons combine with oxygen ions to form H.sub.2O molecules and heat.

A method of shutting down operation of a fuel cell system is disclosed, comprising a fuel cell stack, the method comprising the sequential steps of: i) ceasing a supply of fuel to the fuel cell stack; ii) closing a shut-off valve on an exhaust line in fluid communication with a cathode system of the fuel cell system, the cathode system comprising a cathode fluid flow path passing through the fuel cell stack; iii) pressurizing the cathode system with an air compressor in fluid communication with a cathode air inlet port in the fuel cell stack; and iv) ejecting water from the cathode flow path.

An apparatus/system for generating a high-purity nitrogen gas using a fuel cell includes; a fuel cell that operates by taking in air or a gas containing nitrogen and oxygen, and a fuel gas; a dehumidification mechanism that reduces moisture or water vapor content in an exhaust gas that is extracted from the fuel cell and has a lower oxygen concentration than air; and a filtering mechanism which includes a filter using fibers having different degrees of permeation for nitrogen and oxygen and converts the exhaust gas having a reduced moisture or water vapor content into a gas having an increased nitrogen concentration. The filter recovery ratio is higher when an oxygen concentration of a gas to be filtered is lower. The dehumidification mechanism is a pump unit including a water seal pump to provide an adiabatic expansion chamber in which the exhaust gas extracted from the fuel cell expands adiabatically.

A water electrolysis and electricity generating system is equipped with a water introduction flow path, an oxygen-containing gas flow path, an oxygen-containing gas introduction flow path, a first gas-liquid separator, and a dilution flow path. The oxygen-containing gas introduction flow path introduces the oxygen-containing gas that flows through the oxygen-containing gas flow path into the first supply flow path. The first gas-liquid separator separates into a gas and a liquid the gas-containing water that is guided from the first lead-out flow path connected to the first outlet port member. The dilution flow path guides the oxygen-containing gas that flows through the oxygen-containing gas flow path to the first gas-liquid separator as a diluting gas.

A fuel cell system includes: a fuel cell with an anode supply port and an anode discharge port; an anode supply pipe connected to the anode supply port; a fuel gas supplier provided in the anode supply pipe; an anode circulation pipe connecting the anode discharge port and the anode supply pipe at a position between the fuel gas supplier and the anode supply port to each other; a pressure sensor that detects an internal pressure in the anode supply pipe at the position between the fuel gas supplier and the anode supply port; a circulation pump provided in the anode circulation pipe; and a controller that controls the circulation pump. In at least one of a condition where an internal pressure in the anode supply pipe acquired from the pressure sensor meets a value equal to or greater than a first pressure value and a condition where a variation of the internal. pressure meets a value equal to or greater than a first variation, the controller feeds a fuel gas in a direction from the anode supply pipe toward the anode discharge port by controlling the circulation pump.

A purging circuit for purging an anodic compartment of a cell of a fuel cell, this circuit including: a capacity, forming a related volume at least equal to 500 ml, for containing and homogenising a recovery gas, including an inlet and an outlet; a first nonreturn valve to prevent the recovery gas from returning through the outlet and allowing gas to flow from the first outlet to an inlet of the compartment; a second nonreturn valve to prevent gas from being discharged from the capacity through the inlet; a pressure sensor able to measure the pressure of a fluid present in the circuit; a valve controlling the flow of a supply gas to and from the compartment as a function of data of the sensor and allowing gas to flow from the first nonreturn valve to the inlet of the compartment.

A method for generating electrical energy by a fuel cell system operated with a reformate gas is provided. According to this method, a fuel cell system is provided. The fuel cell system has a first reactor and a second reactor. A gas separation unit is also provided. A portion of a first fuel gas is fed to the gas separation unit. A target gas including N.sub.2 or CO.sub.2 is separated by the gas separation unit. The separated target gas is fed into a protective housing of the fuel cell system. An H.sub.2-enriched tail gas formed in the gas separation unit is fed as a second fuel gas for operation of the fuel cell.

Devices, systems, and methods for variable flow rate fuel ejection are disclosed. A variable flow rate ejector comprises primary and secondary inlets, primary and secondary nozzles, and a needle. The primary nozzle is connected to receive a first fluid from the first inlet chamber and transmit the first fluid through a primary nozzle opening. The needle is disposed within the primary nozzle opening and is axially movable to vary an area of primary nozzle opening. The primary nozzle opening and the needle are sized to make the flow of the first fluid have a supersonic speed. The secondary inlet opens into a second inlet chamber positioned outside the primary nozzle opening. A portion of the second fluid is entrained in the flow of the first fluid from the primary nozzle. The secondary nozzle opening is sized to make the flow of the first and second fluids have a subsonic speed.

A separator, subassembly for a separator, and method for heating a second outlet of a separator are disclosed. The separator has a housing with an inlet configured for introduction of a fluid stream into the housing, a first outlet configured for discharge of the fluid stream from the housing, and a second outlet configured for discharge from the housing of deposits which have been separated from the fluid stream. The separator also has, within the housing, a heat-conducting element within the housing and arranged in such a way that, an end of the heat-conducting element is arranged in or adjacent to the fluid stream and another end is arranged on the second outlet. The separator can also have a gas line in or on the housing that is connected fluidically to the second outlet so as to guide a heated gas to the second outlet.