The use of platinum, a precious metal, is regarded as the biggest cost driver in fuel cells. This is needed as a catalyst to operate the fuel cell. The material is distributed as particles on carbon powder. However, the desired catalytic process only takes place on the surface of the platinum particles, which means that large amounts of the expensive material are wasted.
In a process newly developed by Volkswagen and Stanford University, platinum atoms are specifically placed on a carbon surface to produce an extremely thin layer. The process, a modified version of Atomic Layer Deposition (ALD), allows the required amount of platinum to be reduced to a fraction. In addition, the efficiency of the newly developed fuel cell catalyst is tripled compared to the current technology, while at the same time its durability is increased.
According to professor Prinz from Stanford University, this technology opens up enormous opportunities for cost reduction by minimizing the amount of precious metal used. At the same time, service life and catalyst performance both increase. In addition to the fuel cell, atomic layer deposition also offers a whole range of other applications that require high-performance materials, including next-generation lithium-ion batteries.
According to Volkswagen, the fuel cell has great potential for emission-free mobility. The advantages over current battery electric vehicles are significant. In terms of efficiency, range and refueling time, cars with fuel cells are comparable to conventional combustion engines. The vehicle only emits water and heat as emissions. The new catalyst technology would bring about an enormous increase in economic efficiency, said Thomas Schladt from Volkswagen Group Research. This would make the fuel cell a real alternative to battery electric drives and the classic combustion engine. The researchers' task now is to transfer the results obtained in the laboratory to large-scale industrial production. As to a possible time horizon, Volkswagen did not elaborate.