Chinese Scientists Quadruple Hydrogen Fuel Cell Power With New Proton Interface

Scientists at the Beijing Institute of Technology (BIT) have found a way to roughly quadruple the power output of hydrogen fuel cells, an advance they say could extend their use from road vehicles to space missions. The study was published in the peer-reviewed journal Science.

Fuel cells convert the chemical energy in hydrogen directly into electricity, producing only water as exhaust. The team worked with proton-exchange membrane fuel cells (PEMFCs), the type already used in many hydrogen-powered vehicles, which typically convert 50-60% of their hydrogen fuel into electricity. The bottleneck, researchers say, is how fast protons can move through the fuel cell's catalyst layer — industry-standard materials tend to form tightly packed structures at the nanoscale that slow this movement.

The BIT team designed a new interface that works like a relay race: instead of travelling directly to the catalyst surface, protons hop between intermediate "islands," an arrangement called a Brønsted acid-Lewis base interface. Laboratory tests found the new material increased proton diffusion tenfold, improved proton conductivity by a factor of 6.5, and more than halved the energy barrier protons must overcome.

Under standard conditions, the new design produced four times as much power as conventional fuel cells while using only a small amount of platinum, the expensive catalyst metal fuel cells typically require. Measured per gram of platinum, the device delivered 6.9 kilowatts, outperforming current state-of-the-art technology. After 30,000 cycles of accelerated stress testing, it retained 63% of its initial peak power, versus about 30% for conventional systems.

"The power stack of a fuel cell vehicle can be made smaller and lighter, and the vehicle can get stronger continuous output and a longer driving range," said Li Jie, an assistant professor at BIT and one of the paper's authors. She said the composite material is suited to mass production — the lab can currently make about 100 grams in three days, enough for ten 100-kilowatt-class stacks — and that the efficiency gains could be especially useful for space missions using liquid oxygen.