Nissan Fuel Cell Stack Achieves World-Beating Power Density

Toyota is to hybrids what Honda is to fuel cell vehicles, and what Nissan is to EVs. Or at least that is the traditional view. Perhaps Honda has more fuel cell patents, but that does not mean that companies like Nissan are not also working on their own solutions – and catching the leaders up rapidly.

Nissan has made significant strides forward from the fuel cell stack that it fitted to its 2005 test vehicle, the X-Trail FCV. The latest version revealed to the public on October 13th has a power density 2.5 times greater than this earlier model, putting it at the top of its class for an automotive fuel cell. What this means in practice is that a much more compact unit can provide the same power output, allowing it to be fitted under the floor of the vehicle.

The new fuel cell stack has a power output of 85 kW from a unit that weighs 43kg and has a volume of 34 liters. In comparison, although the 2005 X-Trail FCV lease vehicle fuel cell had a power output of 90kW, it weighed in at 120kg and took up 90 liters volume of space.

A big factor in this downsizing has been the change in design from a unit that had 3 layers of 150 cells in each, to a  single layer of 400 cells. This was achieved by molding the supporting frame of the Membrane Electrode Assembly integrally with the MEA and the separator flow path.

Also reducing the cost is the fact that the new fuel cell stack uses only 1/4 of the platinum required in the 2005 version, which has been a major factor in Nissan being able to reduce the cost of the fuel cell to 1/6 of its predecessor.

Hiromasa Sakai who heads up the fuel cell research effort at Nissan states, “We will be continuing to make improvements based on this new stack.” He went on to state that it is their aim to bring a fuel cell passenger vehicle to market in the sub-10 million Yen price range sometime after 2015.

Sources: Nissan (English), Nissan (Japanese), Nikkei BP (Japanese), Response (Japanese)