Incheon, Harvard Researchers Improve Fuel Cell Durability With Innovation

Incheon, Harvard Researchers Improve Fuel Cell Durability With Innovation

Scientists from the Incheon University in South Korea and Harvard University have developed a fatigue-resistant electrolyte membrane with an interpenetrating polymer network, which prolongs the lifespan of fuel cells.

In hydrogen fuel cells, electrolyte membranes frequently undergo deformation and develop cracks during operation. The research team from these universities has recently introduced a fatigue-resistant polymer electrolyte membrane for hydrogen fuel cells, employing an interpenetrating network of Nafion (a plastic electrolyte) and perfluoropolyether (a rubbery polymer).

“This innovation will not only improve fuel cell vehicles but also promises advancements in diverse technologies beyond transportation, spanning applications from drones to desalination filters and backup power sources,” Incheon University said in a statement.

A novel approach to addressing environmental challenges is developing and commercializing robust hydrogen fuel cells. These cells contain a polymer electrolyte membrane that serves as a barrier between the electrodes (the conductors that enable the flow of electricity through a substance). This membrane conducts protons but inhibits the movement of electrons, hydrogen molecules, and oxygen molecules.

When a vehicle speeds up or slows down, the fuel cell operates inconsistently, leading to varying water production and causing the membrane to expand and contract. The repetitive deformation over time results in the formation of cracks, accelerating the undesired transport of hydrogen through the membrane and ultimately causing operational failure. Some methods employed to address these cracks include radical scavengers and hydrocarbon electrolyte membranes. However, while these approaches offer some defense, they cannot entirely prevent the formation and propagation of these cracks.

Now, in a recent study published in the journal Advanced Materials on 31 December 2023, led by Associate Professor Sang Moon Kim from Incheon National University and Professor Zhigang Suo from Harvard University, a team of researchers has developed a polymer electrolyte membrane that is resistant to fatigue.

Dr. Kim said, “To ensure the long-term stable operation of fuel cells, it is essential to develop an electrolyte membrane with high resistance to repetitive fatigue failure that reflects the actual operating environment and degradation process of fuel cells. In our study, we utilized an interpenetrating network to distribute repetitive stress intentionally.”

In this study, the researchers created a category of fatigue-resistant electrolyte membranes consisting of an interpenetrating network of Nafion and perfluoropolyether (PFPE). Nafion is a commonly utilized plastic electrolyte with proton-conducting properties, while PFPE creates a durable, rubbery polymer network. The incorporation of the rubber slightly diminishes electrochemical performance but markedly enhances fatigue threshold and lifespan.