Second propulsion system planned for Chevrolet Volt
E-Flex hydrogen fuel cell continues move toward
GM has unveiled the next iteration of the E-Flex
electric architecture, configured with GM’s newest,
most efficient hydrogen fuel cell system to date.
This second variant of the E-Flex system uses GM’s
new fifth-generation fuel cell propulsion technology
and a lithium-ion battery to provide up to 300 miles
of petroleum and emissions-free electric driving.
The fuel cell E-Flex is a true Zero Emission Vehicle
(ZEV) and operates all-electric from both hydrogen
fuel cell-generated electricity and grid electricity.
It is plug-in capable, adding up to 20 additional
miles each time it is charged, further reducing
trips to the refueling station.
The E-Flex system is a flexible all-electric production
vehicle architecture that can be configured to run
on electricity from a number of sources. It was
first shown in January at the North American International
Auto Show in the Chevrolet Volt concept vehicle.
The Volt is an electric battery vehicle with 40
miles of all electric-range and uses a small bio-fuel
engine with a generator to extend its range to 640
The General Motors E-Flex Fuel Cell variant - the
second propulsion system developed for the Chevrolet
Volt - is configured with GM’s most efficient hydrogen
fuel cell system to date.
“The beauty of our E-Flex strategy is that it allows
us to package various propulsion systems into the
same space depending on what energy is available
locally,” said Larry Burns, GM’s vice president
of Research and Development and Strategic Planning.
“It also provides flexibility in the sources of
energy. We can obtain hydrogen or electricity from
a myriad of renewable sources - wind, solar, geothermal,
hydroelectric and biofuels - or from traditional
sources such as natural gas, clean coal, nuclear
or even gasoline.
“E-Flex provides flexibility in two ways: in the
propulsion systems that can be used, and in the
sources of energy that can be commercialized to
compete with oil and meet global transportation
growth in a sustainable way.”
Independent studies indicate hydrogen fuel cell
vehicles offer superior overall efficiency and fewer
greenhouse gas emissions compared to internal combustion
engines running on gasoline, when considering both
the creation of the energy and its use in the vehicle.
GM’s fifth-generation fuel cell system is half the
size of its predecessor, yet it provides the same
power and performance. The fourth generation currently
powers the Chevrolet Sequel concept vehicle. The
Sequel stores 8 kg of hydrogen and delivers a range
of 300 miles. The fuel cell Volt will also deliver
300 miles of range, but with only 4.0 kg of hydrogen.
GM’s advancements are a strong indication that our
fuel cell technology has the potential to be a competitive
alternative to the internal combustion engine in
size, performance and cost.
“Our progress has made us increasingly confident
that our fuel cell propulsion system will be automotive-competitive,”
said Burns. “But before this technology can be made
widely available, governments, energy suppliers
and infrastructure companies around the world need
to collaborate with GM and the auto industry to
develop a market for fuel cell vehicles and hydrogen
A variety of technological advancements and lightweight
materials contribute to the efficiency of the Volt.
With an estimated curb weight of 3,500 pounds, it
weighs 30 percent less than the Sequel. The fuel
cell propulsion system is packaged entirely under
the hood and is equivalent in size to a four-cylinder
engine with automatic transmission. The Volt features
molded GE plastic panels on the fenders, window
glazings, instrument panel and steering wheel, which
offer between 30 percent and 50 percent weight reduction
The E-Flex fuel cell variant also showcases GM’s
third-generation wheel hub motors, packaged inside
the rear wheel to add considerable torque for all-wheel
electric drive capability. The new coreless motor
technology reduces mass and produces more power
compared to the first generation shown in 2003.