Technology Status of Hydrogen Road Vehicles

Cleghorn, S., et al., “PEM Fuel Cells for Transportation and Stationary Power Generation
Applications,” Los Alamos N.L., New Mexico, USA, pp. 1637-1646.
This paper describes LANL’s efforts to develop a low cost/high performance hydrogen or reformate air stack,
based on ultra-low Pt loadings and on non-machined inexpensive elements for flow fields and bi-polar plates.
On-board methanol reforming is compared to direct methanol FCs in light of significant power density
increases of the latter.
The achievements so far are:
! Thin-film catalyst layer application gives ultra-low Pt loadings of 0.2 g/kW, which in 5,000-h tests
produced 6 kW/m 2 using pressurized H 2/air
! Off-the-shelf stainless steel screens as flow fields, in place of the expensive machined metal ones normally
used, showed relatively good performance;
! A significant increase in CO tolerance at anode to >>100 ppm with reformed hydrocarbon
! The record high performance of polymer electrolyte direct methanol FCs with Nafion as hot as 130ºC,
already achieved by Siemens, has been repeated, and the future of this FC is promising provided that
catalyst loadings can be further reduced or changed, long-term stable performance is demonstrated, and
that methanol cross-over to the cathode can be minimized to acceptable levels.
The authors feel that commercialization is likely to occur for stationary applications first, because of less
stringent requirements on overall cost, space, and nature/source of the H 2 fuel; the PEM FC, even in relatively
small sizes by comparison with molten carbonate or solid oxide FCs, could be attractive in some applications
such as peak power, demand-side management, and dispersed power generation.
Mantegazza, C.; A. Maggiore, “PEFC Activities at DNP,” De Nora, Milan, Italy, pp. 1647-1656.
This paper is a review of the work since 1990 developing 5- and 10-kW PEM FCs, especially for the bus of
Item 6 Table 1 and the car of Item 9 Table 2.
The present approach is to develop a metallic material for the stack structure with good crash resistance, lowcost
production potential, corrosion resistance, commercial availability, and recyclability, compared to the
precise and delicate materials used so far.
The first 5-kW unit had low power density of 40 W/kg, easily improved to about double by going to lowvoltage,
high-current stack design; so far >6000 h in 40 units of various sizes have been accumulated.
A small (0.5-kW) unit with reformed methanol containing 500 ppm CO has also been successfully
demonstrated.
The 10-kW prototype for Item 9 Table 2 was tested in January 1996 at 100 W/kg.
By 1999, a 250-W/kg unit is foreseen, and stack selling prices should drop to $600/kW, opening commercial
possibilities, at least in the stationary field.
Barbir, F., “Control Strategy for a Vehicular Fuel Cell Power System,” Energy Partners, Florida, USA,
pp. 1695-1705.
As part of the FC car development of this company (Item 13 Table 1), various control strategies have been
simulated.
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