In a humidifier in which an inlet head and an outlet head are connected to one end and another end of a cylindrical housing of a humidifying module, a humidified-fluid inlet joint is connected to the inlet head via a first joint connection, and a fluid-to-be-humidified outlet joint is connected to the outlet head via a second joint connection, clearances that are capable of adjusting connecting positions in directions of the connecting surfaces are provided on the joint connections as well as on connections between the housing and the inlet head and the outlet head.

A method of controlling a hydrogen/oxygen producing system is a method of controlling a hydrogen/oxygen producing system including a water electrolysis apparatus that electrolyzes liquid water by applying current to an anode and a cathode, and a hydrogen gas pressurizing part that pressurizes hydrogen at downstream of the water electrolysis apparatus by applying current to a pressurizing part anode and a pressurizing part cathode. A controller controls current applied to the water electrolysis apparatus and current applied to the hydrogen gas pressurizing part. When the hydrogen/oxygen producing system is stopped, the controller performs first decompression processing such that a decompression speed of the pressurizing part cathode of the hydrogen gas pressurizing part does not exceed a basic decompression speed and performs second decompression processing such that a decompression speed of the anode of the water electrolysis apparatus does not exceed the decompression speed of the pressurizing part cathode.

A humidifier for a fuel cell is provided. The humidifier includes a membrane having a humidifying membrane, a first cap coupled to a first side of the membrane to feed supply air into the humidifying membrane, and a second cap coupled to a second side of the membrane to release humidified supply air. An exhaust air inlet is coupled to the second side of the membrane to inject exhaust air from a fuel cell stack into the membrane, and an exhaust air outlet coupled to the first side of the membrane to release dehumidified exhaust air to an exhaust line. The first cap includes a supply air inflow passage and a variable member that has at least a portion capable of entering the supply air inflow passage. The variable member is moved in an inward direction or in an outward direction based on pressure inside the supply air inflow passage.

The air valve includes a supply valve configured to open and close an air supply passage through which the air gas to be supplied to the fuel cell stack from outside flows; a switching valve configured to switch between a state in which the air gas supplied from the outside flows through the air supply passage and a state in which the air gas supplied from the outside flows through a bypass passage that branches from the air supply passage; and a link mechanism connected to the supply valve and the switching valve and configured to actuate the supply valve and the switching valve. The link mechanism includes an arm portion fixed at the supply valve; and a cam plate fixed at the switching valve, wherein the cam plate includes a guide portion with which the arm portion is to contact.

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.

A fuel cell system includes: an upstream side flow path forming a flow path from an oxidation gas supply apparatus toward a fuel cell; and a downstream side flow path forming a flow path from the fuel cell toward an atmosphere. The fuel cell system includes: an oxidation gas pressure sensor that measures a pressure inside the upstream side flow path; and a controller that can execute a water content estimation mode of estimating a water content in an oxidation gas flow path including the fuel cell. The controller includes: a water content calculation unit that calculates the water content in the oxidation gas flow path including the fuel cell on a basis of an oxidation gas flow rate and an oxidation gas pressure loss.

One or more methods of obtaining an optimal design of a fuel cell having fluid flow networks. In one or more methods, air, hydrogen, and coolant flow networks are simultaneously designed using porous media optimization and Turing pattern dehomogenization.

A method of designing a fuel cell includes executing one or more programs on one or more computing devices having one or more processors to predict a location of one or more liquid regions and one or more vapor regions in microchannels at an air layer of a plate of the fuel cell. Based on the prediction, fluid flow networks for the air layer, a hydrogen layer, and a coolant layer of the fuel cell are simultaneously optimized via homogenized flow optimization. In response to the results of the homogenized flow optimization, one or more multi-scale Turing-patterned microstructures are generated for the air layer and the hydrogen layer. One or more multi-scale Turing-patterned microstructures are generated for the coolant layer by stacking the air layer and the hydrogen layer.

A fuel cell system comprises: a gas-liquid separator separating exhaust gas of a fuel cell stack into a liquid component and a gas component and storing liquid water of the liquid component; a circulation pipe; a drain pipe discharging the liquid water; and a drain valve opening and closing the drain pipe. In an end scavenging process that is executed when operation of the fuel cell system is finished, the control unit opens the drain valve when a valve opening condition for the drain valve is satisfied. The valve opening condition is set such that an amount of the liquid water stored in the gas-liquid separator at the time the drain valve is opened in the end scavenging process is larger than an amount of the liquid water stored in the gas-liquid separator at the time the drain valve is opened during normal operation of the fuel cell system.

A vehicle may include a fuel cell system configured for generating electrical energy used in the vehicle using hydrogen, an engine system including an engine and configured for generating power of the vehicle using hydrogen, an exhaust system that purifies exhaust gas discharged from the engine, and a hydrogen supply system connected to the fuel cell system, the engine system and the exhaust system, and configured for supplying the hydrogen used in the fuel cell system and the engine system, and ammonia (NH3) used in the exhaust system.