Page 169 - Automotive Engineering Powertrain Chassis System and Vehicle Body

CH AP TER 6 .1 Battery/fuel-cell EV design packages

According to one calculation based on current market a voltage of 90 V, which is transformed up to 250 V for
prices, the energy content of hydrogen generated by powering the synchronous electric motor, at a 92%
electrolysis using solar radiation with photovoltaic cells transformer efficiency and 90–92% motor efficiency.
equals gasoline at roughly $10 a gallon. Nickel–metal hydride batteries are used to start up the
fuel-cell auxiliary systems and for braking energy re-
generation. Some 8 kg of liquid hydrogen is stored in an

6.1.7.2 Ford P2000 on-board cryogenic container, (a), at 253 C to achieve
the excellent range. Renault insist that an on-board re-
Mounting most of the fuel-cell installation beneath the former would emit only 15% less CO 2 than an IC engine
vehicle floor has been achieved on Ford’s FC5, seen as against the 50% reduction they obtain by on-board liquid
a static display in 1999, with the result of space for five hydrogen storage, Fig. 6.1-25.
passengers in a medium-sized package. Their aim is to According to Arthur D. Little consultants, who have
achieve an efficiency twice that of an IC engine. The developed a petrol reforming system, a fuel-cell vehicle
company points out that very little alteration is required thus fitted can realize 80 mpg fuel economy with near
to a petrol-distributing infrastructure to distribute zero exhaust emissions. The Cambridge subsidiary Epyx
methanol which can also be obtained from a variety of is developing the system which can also reform methanol
biomass sources. Oxygen is supplied in the form of and ethanol. It uses hybrid partial oxidation and carbon
compressed air and fed to the Ballard fuel-cell stack monoxide clean-up technologies to give it a claimed ad-
alongside reformed hydrogen. Ford use an AC drive vantage over existing reformers. The view at (b) shows
motor, requiring conversion of the fuel cell’s DC output. how the fuel is first vaporized (1) using waste energy
Even the boot is accessible on the 5-door hatchback so from the fuel cell and vaporized fuel is burnt with a small
much miniaturization has already been done to the amount of air in a partial oxidation reactor (2) which
propulsion system. The vehicle also uses an advanced produces CO and O 2 . Sulphur compounds are removed
lighting system involving HID headlamps, with fibre- from the fuel (3) and a catalytic reactor (4) is used with
optic transmission of light in low beam, and tail-lights steam to turn the CO into H 2 and CO 2 . The remaining
using high efficiency LED blade manifold optics. The CO is burnt over the catalyst (5) to reduce CO 2
company’s running P2000 demonstrator, Fig. 6.1-24, concentration down to 10 ppm before passing to the fuel
uses fuel in the form of pure gaseous hydrogen in cell (6).
a system developed with Proton Energy Systems.
6.1.7.4 Prototype fuel-cell car
6.1.7.3 Liquid hydrogen or fuel
reformation Daimler-Chrysler’s Necar IV, Fig. 6.1-26, is based on the
Mercedes-Benz A-class car and exploits that vehicle’s
Renault and five European partners have produced duplex floor construction to mount key propulsion sys-
a Laguna conversion with a 250 mile range using fuel-cell tems. The fuel cell is a Ballard PEM type, 400 in the
propulsion. The 135 cell stack produces 30 kW at stack, developing 55 kWat the wheels to give a top speed

Fig. 6.1-24 Ford P2000 fuel cell platform with two 35 kW Ballard stacks.

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