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top-ofs is 420 miles (the gas tank
has an 8.9-gallon capacity).
(The Model X—which is brought
into the picture here primarily
because of the coincidence more
than anything else—is ftted with a
90-kWh battery pack and has 250
miles of all-electric range.)
Speaking of the second-generation
Volt, Fletcher says, "This is an
efciency story." Efciency right
across the board.
The frst-generation vehicle was a
model year 2011 car. And the team
that developed that one pretty much
stayed intact and set to work on
what has become the 2016 model.
Not only were they able to access
vehicle information from OnStar
(drivers were able to opt in to the
program), but Fletcher explains that
they spent a lot of time talking
to customers. "They told us what
they loved," she says. "And they
told us what we needed."
She adds, "We gave them more of
what they loved."
One of the things they loved was
electric range. So that was a key
development target.
You might think that the way to
achieve more electric range would
be to add more batteries in the
5.5-ft long T-shaped housing (like
the one used in the frst-generation
vehicle, albeit one made of a more-
robust and cost-efective SMC
material from Continental Structural
Plastics, which also supplied the
original, and one with an integrated
tray seal). GM engineers along
with those from supplier LC Chem
actually did something more clever
than that: they revised the chemistry
for the lithium-ion batteries. As a
result, they were able to reduce the
number of prismatic cells in the
battery, from 288 to 192, while
increasing the battery capacity,
from 16 kWh to 18.4 kWh. That's
approximately a 20% improvement.
In addition to which, they were
able to reduce the mass of the
overall battery by some 20 lb., and
Fletcher points out that because
there are fewer cells, there are
fewer connections, which can
result in higher reliability.
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