Mercedes-Benz Leads Industry in Fuel Cell Research
Good Evening Hawkeye -
There's been quite a bit of discussion of late about the problems of hydrogen storage, etc. Here is a press release from Mercedes-Benz, which discusses advances in their fuel cell technology, as well as the fuel issue.
Especially, note how advanced NECAR 3 seems to be. Obviously, press releases attempt to put the best possible face on a story; the truth is doubtless less rosy than portrayed.
But still...
Steve
Mercedes-Benz Leads Industry in Fuel Cell Research
January 29, 1998
Mercedes Fuel Cell Research Cars Already on the Road
STUTTGART - On the heels of its fuel-cell van powered by compressed hydrogen, Daimler-Benz has developed the first-ever fuel cell car using methanol as the fuel. The revolutionary new research vehicle represents a decisive breakthrough in the quest to develop a practical automobile drive system with extremely low emissions.
This latest fuel cell vehicle to emerge from Daimler-Benz laboratories
is known as NECAR 3 (New Electric Car) and, unlike its predecessors, fills up with liquid methanol. With the aid of a steam reformer system located in the rear of the vehicle, methanol fuel is converted on-line into hydrogen through water-vapor reformation. The hydrogen gas is then fed into the Ballard Fuel Cells where it is combined with atmospheric oxygen - but without combustion - to directly produce electrical energy used to power the vehicle.
Hydrogen Tanks and Battery No Longer Needed
Previous fuel cell systems could only operate in conjunction with
bulky hydrogen tanks for fuel storage. With NECAR 3, the entire
process is much more direct: press the accelerator pedal and an
astonishing 90 percent of the system's power is available in just two
seconds. In terms of drive dynamics, this puts proton-exchange
fuel-cell vehicles using methanol on par with conventional gasoline or diesel-powered automobiles.
Dispensing with the hydrogen tanks not only reduces vehicle weight,
but it also greatly improves the everyday practicality for the new
vehicle: the corner gas station can handle methanol, which doesn't
require special safety measures, nearly as easily as gasoline or diesel. What's more, NECAR 3 has a range of some 250 miles (or 400
kilometers on a full tank of 11 gallons (or 40 litres), similar to
conventional vehicles.
Daimler-Benz decided to opt for methanol because it is the best fuel
for generating hydrogen. Although gasoline and diesel fuel were also
considered, their efficiency levels would have been lower. In other
words, there are simply more hydrogen atoms and fewer carbon atoms in every methanol molecule. However, for the introductory phase of fuel-cell powered vehicles at least, Daimler-Benz engineers
are considering the possibility of a multi-fuel concept which, as the
name suggests, would permit using different types of fuel until
methanol is more widely available.
The drive system of NECAR 3 is virtually emission-free. Neither
nitrogen oxides nor soot particles are created during steam conversion of methanol to hydrogen or in the subsequent generating of electrical energy, and carbon dioxide (CO2) emissions are substantially below those of conventional cars.
On-Board Reformer Ideal For Fuel Cell Technology
With the advent of onboard hydrogen generation, a crucial step has
been taken toward developing environmentally-friendly, fuel cell
technology that could eventually power vehicles of the future. An
equally important milestone on the road to this lofty goal is packaging the entire system in a 12-foot-long (3.57 meters) Mercedes-Benz production car. The innovative double-floor sandwich concept employed in the A-Class allows the complete installation of the fuel cells and several auxiliary units underneath the passenger cell. At this interim stage of development, the methanol fuel tank, reformer and control system are located in the rear seat area of the Mercedes research car.
On-Line Conversion and Power Generation
The methanol reformer technology utilized in NECAR 3 has benefited
from a whole range of technological advances at Daimler-Benz. Not only has the system been made smaller and more efficient, but the
performance and dynamic response of the reformation process have also been improved.
The result is a compact unit of some 18 inches (47 centimeters) in
height. Located in the rear seat area, the reformer directly injects
hydrogen "online" into the fuel cells. Hydrogen production occurs at a temperature of some 280 degrees centigrade: methanol and water
vaporize to yield hydrogen (H), carbon dioxide (CO2), and carbon
monoxide (CO).
Following catalytic oxidation of CO, the purified hydrogen gas is fed
to the negative pole of the fuel cell. A special polymer membrane,
which is coated with a platinum catalyst and sandwiched between tow
electrodes, is located here. The hydrogen fuel breaks into
positively-charged protons and negatively-charged electrons, while air (containing oxygen) is supplied to the positive pole of the fuel cell on the other side of the polymer membrane. The hydrogen protons travel through the polymer membrane while the electrons travel through an external circuit to arrive at the positive electrode. There, the oxygen, hydrogen protons and electron combine in a relatively slow,
low-temperature chemical reaction to form water. An electric motor
attached to the external circuit of the fuel cell is then used to drive the vehicle.
Four Mercedes-Benz Research Vehicles in Just Three Years
NECAR 3 is in fact the fourth fuel cell vehicle to roll out of
Daimler-Benz laboratories within the last three years. Development
initially began back in 1994 with NECAR 1, which housed the fuel
cell system in the back of a commercial van. Two years later,
advances in reducing the size of the system made it possible, for the
first time, to install the fuel cell engine in a passenger vehicle - the NECAR 2, based on Mercedes-Benz V-Class van (not sold in the
U.S.). At the start of 1997, it was time for NEBUS, the latest in the
line of fuel cell vehicles, to hit the road. Equipped with 10 fuel cell stacks boasting a total output of 250 kw, NEBUS is suitable for
operation as a normal city bus.
While NECAR 1, NECAR 2 and NEBUS store their gaseous hydrogen fuel in large-volume pressurized tanks, NECAR 3 has no need for an auxiliary energy store, thanks to the methanol reformer. While vehicle range still depends upon the size of the fuel tank, NECAR 3 can fill up with higher-density liquid methanol, unlike its predecessors, almost as easily as any conventional car does with gasoline.
$325 Million Investment for the New Drive System
In the drive to develop fuel cell technology for mobile applications,
Daimler-Benz has joined forces with the Canadian company Ballard
Power Systems. The two companies are investing over $325 million
(CAN $450 million) to advance this pioneering and environmentally-friendly technology. The common aim of the alliance
is to become the first manufacturer worldwide to offer vehicles -
including busses, trucks and series-produces passenger cars - with a
fuel cell engine.
Daimler-Benz is the world's most comprehensive provider of
technologically advance transportation products, systems and
services, and has 290,000 employees and revenues of approximately
$70 billion. Daimler-Benz is focused on the development and manufacture of Mercedes-Benz cars and commercial vehicles,
Freightliner trucks as well as Adtranz rail systems, MTU diesel
engines and TEMIC microelectronics. Daimler-Benz Aerospace builds aircraft and space systems and Daimler-Benz Inter Services provides leasing and sales financing, mobile communications and information technologies. North America, where Daimler-Benz employs more than 19,000 people, is the largest regional market outside of Europe and accounts for approximately 20 percent of worldwide revenues. In 1993, Daimler-Benz became the first German company to list its stock on the New York Stock Exchange (symbol:DAI).
A wholly-owned subsidiary of Daimler-Benz, Mercedes-Benz of North America, Inc. (MBNA) is responsible for the sales and marketing of Mercedes-Benz passenger cars and light trucks in the U.S. through a network of over 300 dealers.
Ballard Power Systems is the world leader in the development of
proton exchange membrane fuel cells. At the heart of its products is
the Ballard Fuel Cell, a proprietary zero-emissions engine that
converts natural gas, methanol, or hydrogen fuel into electricity
without combustion. Ballard Fuel Cells are currently being used by
leading international companies to develop zero-emission vehicles and
clean stationary electric power generators. Ballard Power Systems
common shares are listed on the Toronto Stock Exchange under the
trading symbol "BLD" and on the Nasdaq national market system
under the symbol "BLDPF."
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