The invention relates to a method (1) for leakage monitoring of a fuel cell system (200). According to the invention, it is provided that the leakage monitoring is carried out before or during shut-down of the fuel cell system (200) and during or after restarting of the fuel cell system (200).

According to at least one aspect, a hydrogen gas dispensing system is provided. The hydrogen gas dispensing system includes a source configured to provide a hydrogen gas, a storage device configured to store the hydrogen gas up to a first pressure level, a dispenser configured to dispense the hydrogen gas up to a second pressure level that is higher than the first pressure level, and a compressor configured to compress the hydrogen gas from the source up to the first pressure level for storage in the storage device and configured to compress the hydrogen gas from the storage device up to the second pressure level for dispensing via the dispenser. According to at least one aspect, the dispensing system comprises an input power port configured to receive input power and an output power port configured to deliver output power derived from the input power to charge an electric vehicle.

A fuel cell system includes a fuel cell stack that generates electricity using fuel and oxidant gases, a reformer that produces the fuel gas by reforming a raw material, a raw material feeder that supplies the raw material to the reformer, a combustor that combusts anode off-gas discharged from the anode of the fuel cell stack, and a controller that controls the raw material feeder. The period of a load-following operation in which the power output of the fuel cell stack shifts from a lower level to a higher level, is divided into multiple sub-periods. For each sub-period, a ratio is determined from the increase amounts in the flow rate of the raw material during the sub-period and the length of the sub-period. The controller controls the raw material feeder to make a ratio on the higher output side smaller than another on the lower output side.

The present disclosure provides systems and methods for producing a hydrogen storage vessel that is lightweight. The hydrogen storage vessel may comprise an inner body and an outer body structured as concentric rings with a conic interface. The vessel may have four material layers, including a barrier layer, an insulation layer, a fiber knit, and an abrasion layer. The fiber knit may be braided to trap the hydrogen, as the barrier layer may not be completely impermeable. Additionally, the fiber braid may be clamped to the outer body, enabling pressure pushing on the inner body to wedge and seal the storage vessel.

In a fuel cell system, when filling hydrogen into a hydrogen tank is determined to be started, a transmitter configured to transmit a signal indicating pressure in the hydrogen tank to a hydrogen filling device transmits a first signal indicating that the pressure in the hydrogen tank is a first sensor value when the first sensor value detected by a first pressure sensor configured to detect pressure in a filling flow path connecting a filler port and the hydrogen tank is equal to or higher than a reference pressure predetermined to exceed the atmospheric pressure. Moreover, when the first sensor value is lower than the reference pressure, the transmitter transmits a second signal indicating that the pressure in the hydrogen tank is a second sensor value detected by a second pressure sensor configured to detect pressure in a supply flow path connecting the fuel cell and the hydrogen tank.

Provided is a method of controlling a fuel cell system having a fuel cell stack, a reformer configured to reform a raw fuel and supply the reformed raw fuel to the fuel cell stack, a fuel flow rate control unit configured to control a flow rate of the raw fuel supplied to the reformer, an air supply pipe configured to supply oxygen to the raw fuel, and a combustor configured to mix a cathode discharged gas and an anode discharged gas discharged from the fuel cell stack and combust the mixed gas. The method of controlling the fuel cell system includes detecting at least one of a current value generated from the fuel cell stack and an oxygen supply amount supplied from the air supply pipe; estimating a composition of the anode discharged gas on the basis of at least one of the current value and the oxygen supply amount; and controlling a temperature of the combustor by adjusting the flow rate of the raw fuel using the fuel flow rate control unit on the basis of the estimated composition of the anode discharged gas.

Provided are a method and system for correcting an offset of a hydrogen pressure sensor. The method includes constantly supplying the hydrogen to the fuel cell stack, determining whether an offset of the hydrogen pressure sensor needs to be corrected based on a stop time before the fuel cell stack starts and a magnitude of an output voltage of the fuel cell stack, calculating an offset correction value when the offset of the hydrogen pressure sensor needs to be corrected, and correcting the offset of the hydrogen pressure sensor and performing the starting of the fuel cell stack.

The present invention concerns a system and a fuel ejector for controlling the fuel flow in proton exchange membrane fuel cells. The ejector comprises a nozzle receiving pressurized fuel from a first inlet into said ejector and including a first tapered section narrowing towards the outlet end of said nozzle in order to provide a flow of fuel, a second inlet for receiving recirculated fuel from a proton exchange membrane fuel cell, a diffuser comprising at least a second tapered section receiving fuel from said nozzle and said second inlet, and an outlet for delivering fuel from said diffuser to the anode system of said proton exchange membrane fuel cell. A shaped elongate rod having a butt end and an opposite pointed is movable lengthwise along its axis to engage with said first tapered section in order to provide a fuel flow control means for the fuel at the outlet of said nozzle. The rod is extending to said at least one second tapered section in order to provide a restriction means for a fuel flow through said diffuser, and wherein said rod is provided at its butt end with a control mechanism arranged to move said rod lengthwise in order to vary the fuel flow path geometry at the outlet of said nozzle and at said diffuser.

According to one aspect of the present invention, a hydrogen production apparatus includes a hydrogen production mechanism configured to produce a hydrogen gas from a raw material by using a catalyst; and an operation control circuit configured to input a parameter value as an index indicating a state of the catalyst, and configured to control an operation maximum load of the hydrogen production mechanism to be variable in correspondence with the parameter value.

A hydrogen generation electricity system for producing electricity from hydrogen using a hydrogen carrier substance, comprising: a reaction chamber arranged for generating a H2 gas stream by converting the hydrogen carrier substance; wherein the reaction chamber comprises an inlet arranged for receiving the hydrogen carrier substance; an output conduit for exiting the H2 gas stream; a fuel cell arranged for producing electric energy by converting hydrogen; the output conduit is arranged for supplying the H2 gas stream from the reaction chamber to the fuel cell; the system further comprising: a humidity determining unit arranged for determining a humidity level of the H2 gas stream; a water providing means for providing H2O to the reaction chamber; and a water vapour control means arranged for controlling the water vapour level in the reaction chamber, in response to the determined humidity level, wherein the generated H2 gas stream comprises hydrogen and water vapour.