Prolonging Fuel Cell Service Life

Designing gas diffusion layers (GDLs) for hydrogen fuel cells that improve efficiency and stability. The GDLs have a porosity gradient along their length to enable uniform oxygen distribution over the fuel cell cathode catalyst layer. This prevents hotspots, water accumulation, and uneven reactions that reduce fuel cell performance.

Improving the durability and conductivity of fuel cell membranes by adding a nanofiber antioxidant, cerium hydrogen phosphate (CeHPO4), to the membrane. The antioxidant scavenges destructive radicals produced in the fuel cell to protect the membrane without reducing proton conductivity like conventional antioxidants. The nanofiber form provides high dispersibility in the membrane. The membranes with dispersed CeHPO4 show improved proton conductivity and durability in fuel cells.

Designing gas diffusion layers (GDLs) for fuel cells that improve efficiency and stability by providing custom porosity gradients. The GDLs have non-uniform porosity along the oxygen flow direction to distribute oxygen evenly over the catalyst layer. This reduces hotspots and water accumulation that can decrease fuel cell efficiency.

Improving the durability and lifespan of fuel cells by avoiding stack deterioration due to mixed potential and reverse currents when the fuel cell is restarted after being stopped. The fuel cell deterioration avoidance method involves selectively recirculating air and hydrogen, controlling anode hydrogen pressure, and managing cooling water temperature based on diagnostic criteria like open circuit decay time and current distribution deviation. This prevents degradation by avoiding conditions prone to mixed potential and reverse currents when restarting the fuel cell.

Fuel cell system that enhances fuel cell lifetime by controlling hydrogen partial pressure in the cell membrane. The system calculates the optimal target hydrogen partial pressure based on the catalyst location in the membrane. A controller adjusts the gas supply to achieve the target. This reduces chemical degradation of the membrane. The catalyst suppresses hydrogen peroxide formation when hydrogen is over-rich. By limiting hydrogen partial pressure, the catalyst location maximizes the suppression effect.

An electrode for a polymer electrolyte membrane fuel cell that contains an antioxidant to improve the durability of the fuel cell. The antioxidant is cerium hydrogen phosphate dispersed as nanofibers. Adding this antioxidant to the catalyst layer of the fuel cell electrode helps protect the membrane from chemical degradation during operation. The antioxidant scavenges radicals that can attack and degrade the electrolyte membrane, thereby minimizing performance loss over time.

A system and method for purging condensate water and hydrogen from a fuel cell stack in a way that improves operation stability and efficiency by accurately and adaptively managing the purging process. The system includes a purge valve that selectively directs the purged water/hydrogen to either the atmosphere or back into the fuel cell humidifier based on stack pressure and conditions.

Fuel cell system design that protects hydrogen system components from damage due to loads like impacts. The design uses a layout where hydrogen system components are placed between the fuel cell stack and air system components. This ensures that if the fuel cell system receives a load, it is possible to suitably protect auxiliary devices which are present at positions where the pressure of the hydrogen gas is high. The upstream hydrogen auxiliary device is placed farther away from the air system component than the downstream hydrogen auxiliary device. This protects the upstream device from impacts.

Fuel cell system that can detect poor quality hydrogen fuel and prevent irreversible degradation of the fuel cell performance. The system uses a pressure sensor to monitor the hydrogen gas pressure in the fuel cell. If, after a certain amount of time, the pressure does not reach expected levels based on the amount of hydrogen supplied, it indicates impurities in the gas. The system then disables power generation to avoid damaging the fuel cell.

A coating for bipolar plates of fuel cells or electrolyzers that provides improved performance and durability compared to previous coatings. The coating is a solid metallic solution containing iridium or iridium and ruthenium in concentrations of at least 99%. The iridium-rich coating has low electrical resistance like gold but is more stable and less prone to corrosion/dissolution. It can also contain small amounts of other noble metals like platinum or gold. The coating may also have an undercoat layer system containing elements like titanium or niobium. The coating is applied to bipolar plates of fuel cells or electrolyzers to improve their corrosion resistance and electrical conductivity.

Process and system to mitigate overpressure in fuel cell anodes to prevent damage in the event of injector failure by detecting a stuck open injector and closing the hydrogen valve to prevent excess supply. The fuel cell stack continues to run and consume hydrogen to deplete the anode pressure. Other actions include opening the anode bleed valve, increasing cathode air pressure, and modulating load to maintain pressure balance.

A fuel cell system that prevents oxygen corrosion and hydrogen safety risks when the system is stopped. The system has dedicated spaces for oxygen and hydrogen to stay when the system is stopped. A control unit adjusts the oxygen-to-hydrogen ratio in those spaces to prevent issues.

Solid oxide fuel cell (SOFC) system that maintains a reducing anode environment after shutdown to reduce anode oxidation. It automatically provides hydrogen to the anode, thermally integrated into the SOFC system and plumbed to deliver hydrogen to an anode flow stream. The hydrogen supply is activated after a transition from steady-state to shutdown, using residual heat to produce hydrogen from a tank and prevent anode oxidation.

Controlling the draining of water from a fuel cell in order to prevent freezing and damage. The fuel cell has a gas-liquid separator to remove water from the exhaust gas. By monitoring the pressure and capacities, the control system can determine how much water is present and open the hydrogen circulation valve to displace the water with gas. This prevents water from remaining in the separator where it could freeze and damage the cell.

Fuel cell with an anode catalyst layer containing a catalyst and electrically conductive material that has a higher electrical resistance when exposed to oxygen compared to hydrogen. The cathode catalyst layer contains a separate catalyst and electrically conductive material. The resistance difference suppresses anode reactions when fuel is replaced with air, which prevents cathode catalyst degradation.