Jahresbericht 2003/2004 - Biba - Universität Bremen

Mobile elektrische Energieversorgung
für Fahrzeuge mit
großer Reichweite und
hoher Beschleunigung
Lead Project “Mobile Power Supply for
Vehicles with Large Cruising Range and
High Acceleration”: The power supply of
electric road vehicles is an alternative
drive-train solution for the reduction of air
pollution in metropolitan areas. Electric
vehicles unfortunately are not as efficient
as conventional vehicles in regard to
cruising range, acceleration, reliability
and market price.
Research is necessary for the development
of more efficient and compatible
energy storage systems. The basic idea
behind the project is the combination of
several energy storage systems with high
energy density on the one hand and high
power density on the other hand and thereby
achieving large cruising range and
high acceleration at the same time. The
combination of different storage systems
will allow the project to greatly enhance
the performance characteristics of electric
vehicles.
An energy storage system with a very
high energy density is used to achieve
the cruising range. High performance
storage systems (e.g. UltraCap, NiMH)
with long service life are used for the high
electric currents needed for the acceleration
and deceleration. The combined
use of energy storage systems requires
the mechanical integration as well as
an adaptable battery management
system (BMS). Therefore a modular, RISC
microcontroller based BMS was developed
at BIBA. The strategies for the energy
management system developed at BIBA
allow for the optimal use of each energy
storage system. To enhance the dependability
of the vehicle the BMS has to be
robust enough to compensate for the
failure of subsystems and has to inform
the driver timely.
In the course of the project the technical
feasibility was demonstrated with two
prototype vans and simulations lead to
an optimised energy management strategy
for the three energy storage systems
(UltraCap, NiMH battery, zinc-air battery).
The manufacturer of the UltraCap
(Epcos) has made preparations to bring
UltraCaps to the mass market to ensure
the availability of the technologies to
marketable prices. The companies Varta
and KU-Tec developed together the recycling
technology for the NiMH battery. The
double-layer capacitor UltraCap is being
improved for peak power performance
and long service life. The components
will be integrated into Mercedes Sprinter
Vans at the DaimlerChrysler Competence
Center for Zero Emission Commercial
Vehicles (KEN) together with BIBA.
Jan Westerkamp
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