BRUSSELS Volkswagen today (Oct. 31) introduced a fuel cell type that in some years could fit for automotive drives, the company said. Fuel-cell-driven cars, however would require a complete different architecture for the control circuits.
The company showed a high-temperature fuel cell (HTFC) with an output power of 5 kW, developed in a seven-year in-house research project. The cell presently would allow for the design of automotive drives with an efficiency of about 45 percent, equaling the efficiency of Diesel motors at its optimum engine speed. However, in more realistic load cycles, the HTFC has the potential to offer a better overall efficiency, a company spokesperson said. "We expect to exceed 50 percent efficiency in the mid-term", he explained.
According to Volkswagen, the new high-temperature type is superior to the approach of low-temperature fuel cells (LTFCs) presently preferred in the industry in that it is far less susceptible for temperature variations: While a conventional low-temperature cell must not exceed temperatures of about 80 degrees Celsius and hence has to rely on a complex, expensive and heavy cooling system, the HFTC operates at temperatures up to 120 degrees which could result in far cheaper and simpler cooling systems.
Volkswagen is aiming at using the fuel cell as energy source for electrically-driven cars that finally could do away with combustion engines. Basically, the fuel cell drive has similarities with today's hybrid drives, "but without combustion engine", said Christoph Kohnen from Volkswagen's technology communication. For instance, a fuel cell-driven vehicle could use energy recuperation processes to improve the energy balance. But while the company believes the HTFC in principle is fit for mass production, the electronic controls would require an extensive redesign. "In such a car, basically everything would be controlled by wire", Kohnen explained. The control circuitry is not yet in place, he said.
Thus, the starting signal for HTFC-driven cars in series production is still a lot of years away - Volkswagen does not expect that affordable reliable vehicles equipped with such a system to hit the streets before 2020. However, first research vehicles will be powered with HTFC fuel cell by 2010.