15 patents in this list

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Modern fuel cell systems operate at power densities of 1-2 W/cm², but face significant challenges in thermal management, water balance, and catalyst degradation. Field data shows that stack efficiency can drop by 10-15% over time due to catalyst poisoning and membrane degradation, while water management issues account for nearly 20% of system failures in real-world applications.

The core engineering challenge lies in maintaining high energy conversion efficiency while simultaneously managing thermal loads, water production, and catalyst longevity across varying power demands.

This page brings together solutions from recent research—including advanced water vapor management systems, integrated methane reforming techniques, CO-tolerant catalyst designs, and thermal optimization strategies. These and other approaches focus on extending operational lifetimes while improving system reliability in commercial applications.

1. High Altitude Aircraft with Thermodynamic Fuel Cell System Utilizing Compressed and Cooled Hydrogen and Air

Joby Aero, Inc., 2023

A hydrogen fueled high altitude aircraft using a thermodynamic fuel cell system that maximizes efficiency and minimizes environmental impacts. The system compresses inlet air using multiple compressors and cools it using liquid hydrogen to maintain low temperature for the fuel cell. The hydrogen is also compressed and expanded before the fuel cell. The exhaust is cooled to condense water that is collected and expelled as ice. The high efficiency hydrogen conversion enables long range flight with lower fuel volumes. The VTOL aircraft can fly at high altitude with reduced environmental impact.

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2. Fuel Cell System with Dilution Air Introduction for Hydrogen Concentration Reduction in Exhaust Gas

HYUNDAI MOBIS Co., Ltd., 2023

Fuel cell system that can reduce hydrogen concentration in exhaust gas. It does this by selectively introducing dilution air into the exhaust gas discharge line from the fuel cell stack. This reduces the hydrogen concentration to safer levels. A bypass line connects the air supply and exhaust discharge lines with an adapter having separate flow paths. The air inlet is larger than the outlet, creating lower pressure in the outlet region so air flows from the supply into the exhaust gas.

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3. Fuel Cell System with Pneumatic Air Integration for Exhaust Hydrogen Dilution

HYUNDAI MOTOR COMPANY, KIA CORPORATION, 2023

A fuel cell system that can reduce the hydrogen concentration in the exhaust gas from a fuel cell stack without adding expensive filters or fans. The system connects the exhaust discharge line to the pneumatic air supply for the vehicle. This allows air from the pneumatic system to be selectively supplied to the exhaust line to dilute the hydrogen concentration when needed, to prevent flammability issues.

4. Fuel Cell Fabrication via Methane Dissociation Using High-Power Microwave Plasma Reactors

Lyten, Inc., 2023

Fuel cell fabrication process that provides zero emissions and even offsets greenhouse gas emissions through the complete and permanent dissociation of methane that would otherwise be either burned or released. The process involves dissociating methane using high-power microwave plasma reactors to separate it into hydrogen gas and solid carbon. The carbon is used to produce fuel cells while the hydrogen fuels clean energy applications. It sources methane from landfill sites, natural gas deposits, etc.

5. Exhaust Water Removal System Using Rotating Sorbent Wheel and Heat Exchanger

Hamilton Sundstrand Corporation, 2023

A method to remove water from hydrogen fuel cell exhaust gases. The method uses a rotating sorbent wheel, heat exchanger, and evaporator in the exhaust flow path. The wheel absorbs water vapor from the exhaust in one section and releases the water into a different section as it rotates. The heat exchanger recovers waste heat from the exhaust. This integrated system aims to capture over 99% of the water content from fuel cell exhaust gases.

6. Fuel Cell System with Water Vapor-Assisted Fuel Gas Mixing and Reforming Catalyst

Kabushiki Kaisha F.C.C., 2022

Fuel cell system that can uniformly supply fuel gas and prevent soot formation. It uses water vapor generated during power generation and mixes it with fuel gas using a reforming catalyst. The water vapor retention member has exhaust ports to allow uniform gas flow and prevent concentration that can cause soot.

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7. Integrated Fuel Cell System with Steam Methane Reformer and CO2 Recycling for Hydrogen and Electricity Production

FuelCell Energy, Inc., 2022

High efficiency, low emission integrated system that produces hydrogen and electricity using a fuel cell with an integrated steam methane reformer (SMR) to convert natural gas to hydrogen. The system includes a water-gas shift reactor, absorber column, PSA purification system, and other components to increase the hydrogen concentration from the SMR and remove impurities. The system also recycles CO2-rich flashed gas and anode exhaust to the SMR to increase heat production.

8. Fuel Cell Membrane Electrode Assembly with Specific Platinum Ratio and Homogeneous Catalyst Distribution

Greenerity GmbH, 2022

A fuel cell membrane electrode assembly with high catalytic activity and improved tolerance to carbon monoxide. The assembly has a cathode with a highly active oxygen reduction catalyst distributed homogeneously in an ionomer. The anode has a hydrogen oxidation catalyst and a CO oxidation catalyst. The ratio of platinum in the hydrogen oxidation catalyst to the CO oxidation catalyst is greater than 3:1. The total platinum loading is less than 0.4 mg/cm2.

9. Fuel Cell System with Current Limitation Based on Temperature, Fuel Supply, and Hydrogen Consumption

Panasonic Intellectual Property Management Co., Ltd., 2022

Operating a fuel cell system to reduce carbon deposition and coking by limiting current output from the fuel cell stack based on temperature, fuel supply, and hydrogen consumption. The current output is capped to prevent under-fueled conditions that promote carbon buildup.

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10. Air Purification System with Water Electrolysis-Based Hydrogen Power Generation

KWaterCraft Co., Ltd., 2022

An energy-independent air purification system that reduces chemical fuel use and greenhouse gas emissions by using hydrogen produced from water electrolysis as a power source. The system uses a water electrolysis unit to generate hydrogen and oxygen from water. The hydrogen is used to generate electricity for air purification, with excess stored in a battery. The oxygen is released into the room.

11. Fuel Cell Anode Exhaust Processing System with Heat Exchangers and Vapor-Liquid Separation for Carbon Dioxide Removal

FuelCell Energy, Inc., 2021

A system and method to remove carbon dioxide from anode exhaust of a fuel cell to increase the hydrogen recovery from the anode exhaust upstream of the PSA. The system uses feed/effluent heat exchangers and vapor-liquid separators to cool and partially condense the anode exhaust gas. This removes and separates liquid carbon dioxide from the remaining hydrogen-rich anode exhaust to be fed to a PSA.

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12. Fuel Cell System with Selective Gas Recirculation and Continuous Cathode Exhaust Release

THYSSENKRUPP MARINE SYSTEMS GMBH, thyssenkrupp AG, 2020

Recirculating fuel cell system that minimizes reactant emissions by selectively recirculating unreacted gases while continuously releasing a portion of the cathode exhaust.

13. Exhaust Gas Dilution Device with Air Mixing Chamber and Catalytic Hydrogen Reduction

HYUNDAI MOTOR COMPANY, 2020

A device to decrease hydrogen concentration in fuel cell exhaust to prevent fire/explosion risks. The device dilutes the hydrogen by mixing with external air before exhaust. It has an air inlet, exhaust gas path, and air dilution chamber. An air pump sucks in air and sprays it into the exhaust via a nozzle. This mixes with the hydrogen. A catalyst further reduces the hydrogen concentration.

14. Exhaust Gas Diffusion Apparatus with Rear Bumper Integration for Hydrogen Concentration Reduction

HYUNDAI MOTOR COMPANY, KIA MOTORS CORPORATION, 2019

An apparatus for reducing hydrogen concentration in exhaust gas of a fuel cell vehicle to prevent explosion and ignition risks from dense hydrogen exhaust. The apparatus involves guiding the exhaust gas to the streamlined rear bumper where it diffuses and mixes with ambient air to reduce hydrogen concentration. This can be achieved using exhaust gas guiding units, air amplifiers or collecting members installed at the rear bumper.

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15. Exhaust System Apparatus with Rear Bumper Integration for Hydrogen Diffusion

HYUNDAI MOTOR COMPANY, KIA MOTORS CORPORATION, 2019

Apparatus to reduce hydrogen concentration in a fuel cell vehicle's exhaust gas. The apparatus connects the exhaust system to the rear bumper and guides the exhaust towards the streamlined bumper surface. This allows the hydrogen in the exhaust to diffuse into and dilute with the surrounding air, reducing the hydrogen concentration.

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