Temperature Regulation in Fuel Cells

Hydrogen generation electricity system that allows precise control of water content in hydrogen gas to optimize fuel cell performance. The system uses a reaction chamber to convert a hydrogen carrier substance like formic acid into hydrogen gas. By controlling pressure and temperature in the chamber, the water vapor concentration in the hydrogen gas stream can be adjusted. This avoids the need for expensive membranes to extract water vapor from the gas for fuel cell use.

Hydrogen storage unit and fuel cell system configurations that can heat or cool the hydrogen storage containers containing metal hydride alloys to enable efficient hydrogen release and absorption for the fuel cell. The hydrogen storage unit has a housing with hydrogen cylinders and an internal temperature control member that circulates a heat medium to heat or cool the cylinders. The fuel cell system uses the same heat medium circuit from the fuel cell stack cooling system to regulate the hydrogen storage temperature. This allows low-cost and efficient temperature control without additional heaters or coolers.

Fuel cell power generation system with a fuel cell, radiator, hydrogen storage, power boosting, distribution units, and partition. The fuel cell is cooled by the radiator. Hydrogen storage supplies the fuel cell. The power boosting unit increases the fuel cell power output. The power distribution unit routes the boosted power. The partition isolates heat from the radiator. This system can be mounted in a vehicle or cargo box and moved to charge an electric vehicle, or used as a stationary power supply with heat isolation.

Cooling system for hydrogen fuel cells in vehicles like aircraft that uses auxiliary cooling during peak power demands. The fuel cell includes a gasifier to convert liquid hydrogen to gas. The cooling system has a regular coolant circuit sized for normal power levels and an auxiliary bypass circuit that diverts coolant around the gasifier. During peak power, the auxiliary circuit is activated to bypass coolant, using the heat of hydrogen gasification to supplement fuel cell cooling. This prevents overcooling and enables a smaller main coolant system for cruise conditions. A controller manages the cooling systems based on power demand and conditions.

A fuel cell system for vehicles like tractors and backhoes that adjusts the temperature inside the hydrogen tank based on the amount of hydrogen remaining. When the hydrogen level gets low, the system increases the tank temperature to release more available gas. This allows quick response to load changes without reducing fuel cell output. It also reduces unused hydrogen left in the tank.

Efficiently heating a coolant in a fuel cell system using a catalytic heater to prevent coolant freezing without using electric resistance heaters. The catalytic heater combusts hydrogen in the anode exhaust, at low concentrations, to provide heat to the coolant storage tank. The catalytic heater contains a catalyst material that spontaneously ignites and combusts hydrogen. This enables using the waste hydrogen from the fuel cell to heat the coolant.

Cooling and heating system for hydrogen fuel vehicles that uses the waste heat and cooling energy from the vehicle's fuel cell power system to provide vehicle cabin heating and cooling. The system utilizes the fuel cell's hydrogen heat exchanger to pre-heat air for the cabin and the fuel cell coolant heat exchanger to provide cabin cooling. It also has radiators to selectively provide additional heating or cooling as needed. The system leverages the fuel cell's existing cooling circuit to capture waste heat and uses the hydrogen's phase change for heating, thus reducing additional energy consumption compared to conventional vehicle HVAC systems.

A high-temperature unitized regenerative fuel cell (URFC) that overcomes the temperature limitations of existing URFCs to improve efficiency. The URFC operates at 120-200°C using a phosphoric acid-doped polybenzimidazole (PBI) membrane. During water electrolysis, water vapor is supplied to the first electrode. This allows higher temp operation and avoids water flooding. The URFC also uses specific catalysts like Pt/Ir2O for the OER electrode.

Fuel cell operation stop process to improve fuel efficiency, prevent carbon deposition, and protect system components during shutdown. When stopping the fuel cell system, it intermittently supplies the fuel and reforming reactants to the reformer, supplies an oxidizing gas to the cathode, and ignites the combustor to burn any remaining fuel. This prevents unburned fuel from being discharged, avoids carbon deposition, and stops oxidation/reduction reactions at appropriate temperatures. The reformer temperature is monitored to determine if fuel/reforming supply should be intermittent.

Controlling a fuel cell stack to recover performance after sustained high-output operation by thermally managing the fuel cell stack. The cooling system is configured to further cool the stack after power generation stops if the stack temperature is above a preconfigured degradation threshold. This uses the cooling system to recover performance and reduce degradation after long high-power runs.

An apparatus for cooling and humidifying fuel cells using bubbles to provide efficient cooling, humidification and impurity removal without dedicated pumps or additional components. The apparatus focuses on novel features and configurations to improve fuel cells efficiency and reliability by using bubbles for cooling, humidification and impurity removal. This is instead of pumps, humidifiers, and complex cooling systems. The key design features are using bubbler cooling to remove heat, provide humidification and impurity removal from the fuel cell, reducing contact resistance between bipolar plates using foam or surfactant additives, and optimizing the foam structure to enhance bubble generation and gas removal.

A fuel cell module design that reduces thermal stress and degradation in the fuel cell stack when operating at high temperatures. The design includes mechanisms like springs, wedges, loose flanges, and matching coefficients of thermal expansion to absorb and compensate for thermal expansion differences between components. This reduces the stress on the fuel cell stack and insulating materials, improving module durability and performance at elevated temperatures.

Regulating the temperature of a fuel cell stack in a vehicle. The method involves pre-heating the stack by temporarily bleeding hydrogen to the cathode side at a calibrated percentage to generate waste heat. The bleed percentage is determined based on the stack's pre-start temperature. After a set time, if the stack has reached the minimum operating temperature, the heating is suspended. If not, the bleed percentage is increased and checked again. This maximizes waste heat generation while minimizing hydrogen waste.

A fuel cell system that improves cooling efficiency and minimizes heat loss compared to conventional systems. The system uses a flow channel switching device to optimize the heat exchange between the fuel cell and a heat storage tank. The switching device redirects the coolant flow through a bypass line when the fuel cell is off, preventing heat loss from the tank, rather than allowing the coolant to cool inefficiently through the storage tank.

Operating a fuel cell system with a proton-conducting membrane to avoid coking and degradation when the system is not fully warmed up. The system measures the stack temperature and fuel supply then limits the current output to prevent excessive carbon deposition. This prevents performance loss due to coking while still allowing dynamic power output adjustments to match load needs.