764GM Moves Ahead on Batteries for Volt; What To Call PHEVs
- Jun 10, 2007In a most welcome step, GM has moved several
steps closer on selecting lithium-ion batteries
for its Volt series plug-in hybrid. Below we
include our overall comments, the news, an
analysis by Technology Review, and links to other
places where you can learn more and post
comments. We conclude with a related light but
significant story from the Detroit Free Press: as
Detroit's media realize that PHEVs are coming,
they raise a new issues: the urgent need for a
consumer-friendly name for plug-in hybrids!
The reports below project that full battery packs
from two suppliers will be tested in labs and
vehicles between now and June 2008. One year from
now, GM will choose a vendor. GM continues to
maintain artificially high requirements, as it
has since announcing the Volt, despite pointed
questions from many directions. GM's management
remains convinced that a car with less than a
40-mile range will be attractive to only a small
niche of consumers. (Even though the round-trip
commuting "sweet spot" is around 25 miles.) And
the need to confirm in advance a 100,000-mile
battery lifetime prolongs the development timetable.
In public and private forums, GM has implied that
those who suggest starting with long-proven (but
heavier) nickel-metal hydride batteries don't
understand the complexity of the design process.
NiMH proponents understand that GM will design
the car's physical space around the lithium-ion
battery's requirements. They do suggest GM use
that space for a similarly-sized NiMH battery
with less range (and of course, design the
appropriate charger and other software.) Yes,
this is more work, but it could get a
demonstration fleet on the road much faster, and,
we think, improve the chances that this vehicle
will succeed. For a graphic depiction of our view
of Prius and GM versions, see a new slide taken
from our presentation, <http://www.calcars.org/calcars-versions.pdf>.
The first five paragraphs of the company press
release give the basic
General Motors has awarded two contracts for
advanced development of lithium-ion batteries for
its electric drive "E-Flex System," it was
announced today at GM's annual shareholder meeting.
GM selected two companies out of the 13 technical
proposals it considered to provide advanced
lithium batteries for both range-extender
electric and fuel cell variants of the E-Flex
architecture. The E-Flex electric vehicle
architecture underpins the Chevy Volt concept car
shown earlier this year and is being developed as
part of GM's strategy to diversify transportation away from petroleum.
One contract will go to lithium-ion battery
supplier Compact Power, Inc., based in Troy,
Mich. CPI is a subsidiary of Korean battery
manufacturer LG Chem. A second contract has been
awarded to Frankfurt, Germany-based Continental
Automotive Systems, a division of Continental
A.G., a tier one automotive supplier that will
develop lithium-ion battery packs. GM continues
to assess other solutions to quickly bring lithium-ion batteries to production.
"The signing of these battery development
contracts is an important next step on the path
to bring the Volt closer to reality," said GM
Chairman and CEO, Rick Wagoner. "Given the huge
potential that the Volt and its E-Flex system
offers to lower oil consumption, lower oil
imports, and reduce carbon emissions, this is a top priority program for GM."
MUSICAL CHAIRS ON BATTERIES
For those who have been following all the
candidates for batteries for PHEVs, for the Volt,
Contintental Automotive will be working with
batteries from A123Systems. (A123, in a
partnership with Cobasys, is also contracted to
develop batteries for the Saturn VUE PHEV.) For
the Volt, CPI/LG-Chem is a new entry. (Not being
considered for the Volt is Johnson-Controls-SAFT,
still in contention for batteries for the VUE.)
Note that the announcement says the company
hasn't foreclosed other options as well.
To follow this issue further, you can read
postings by Denise Gray, Director, Hybrid Energy
Storage Systems, and comments at the GM Fastlane
Blog <http://fastlane.gmblogs.com/archives/2007/06/charging_ahead_1.html> .
At Green Car Congress
you can read technical details on both battery
vendors' products, and read viewers' comments.
Below we've reprinted a longer report from
Technology Review. Among the viewer comments
you'll see some responses that will interest
those who write us asking about AltairNano's
long-cycle batteries and EEStor's
ultracapacitors. (Quick answer: Altair's products
are only beginning to be evaluated by third
parties and EEStor has not released anything.)
Technology Review, Thursday, June 07, 2007 By Kevin Bullis
New Batteries Readied for GM's Electric Vehicle
The technologies behind the battery packs for the
GM Volt are being tested and could be ready within a year.
This week, General Motors (GM) announced its
selection of battery makers to develop and test
battery packs for use in its proposed electric
vehicles. The selected battery makers, Compact
Power, based in Troy, MI, and Continental
Automotive Systems, based in Germany, say that
they've overcome the performance and cost
limitations that have been an obstacle to electric vehicles in the past.
Over the next 12 months, researchers from,
Compact Power, Continental Automotive Systems and
GM will be testing the battery-pack designs in
the lab and in vehicles to confirm that the packs
can work for the life of the car--at least 10
years, says Denise Gray, director of hybrid
energy storage devices at GM. Initial tests of
individual battery cells, along with projections
about the performance of battery packs that can
contain hundreds of these cells, have Gray
optimistic that her company will have proven packs by June 2008.
If the packs perform well, they are slated for
use in the proposed Chevrolet Volt, an electric
concept car announced by GM in January. The Volt
marks a change in emphasis for GM, which
previously focused on more distant plans to bring
hydrogen-fuel-cell-powered cars to market. The
Volt could be ready within a few years. Until
now, however, it has been unclear who would develop its advanced batteries.
There are a number of design variations for the
Volt, but they will all be propelled by electric
motors. In one version, the battery pack, which
can be recharged by plugging it in, will provide
40 miles of range. Then an onboard gasoline- or
ethanol-powered generator will kick in to
recharge the battery, providing an additional 600
miles of range. A proposed hydrogen-fuel-cell
version would have a smaller battery pack and no onboard generator.
To make batteries that are up to GM's
specifications, battery makers have had to
redesign the chemistry of lithium-ion batteries,
a type of battery widely used in mobile phones
and laptops. While lithium-ion batteries are
light and compact, the type of lithium-ion
battery typically used in electronic devices
relies heavily on cobalt, an expensive metal. The
cobalt oxide used in one of the battery's
electrodes isn't thermally stable, making the
batteries prone to bursting into flame if damaged
or poorly manufactured--a shortcoming that led to
the massive recall of millions of laptop computer
batteries last year. (See "Safer Lithium-Ion
Batteries.") This could be a problem in vehicle
battery packs, which would be much larger than
those in portable electronics, so an accident could be more dangerous.
One alternative is to replace cobalt with
manganese. Mohamed Alamgir, director of research
at Compact Power, says that manganese-oxide
electrodes are significantly more thermally
stable than cobalt oxide, and less expensive. The
battery maker has also developed a new material
for keeping the electrodes separate: the material
remains stable at higher temperatures than
conventional materials, further guarding against
the runaway heating that causes batteries to
catch fire. What's more, the company makes the
batteries in a flat shape rather than in the
typical cylindrical design. Alamgir says this
flat shape prevents heat from building up at the
center of the cell, making it easier to keep the
battery at an even, cool temperature.
A123 Systems, a company based in Watertown, MA,
that will supply battery cells to Continental,
has taken a different tack, turning to an
iron-based cathode that is even more thermally
stable than manganese oxide. Better still, iron
is cheap and abundant. (See "More Powerful Hybrid
Batteries.") The electrodes are not oxide
materials but phosphates, a chemistry that more
closely binds oxygen, preventing it from being
freed from the material, which would allow the
battery's flammable electrolyte to catch fire.
Such materials do not allow for fast charging or
delivery of big bursts of power, so researchers
modified them, in part by doping the material and
by forming the material as nanoparticles. The
A123 batteries were developed for use in power
tools but have since been modified to store more
energy, making them better suited for use in
electric vehicles such as the Volt.
The battery packs for the Volt must include
complex electronics for ensuring that each cell
is charged and discharged properly. If individual
cells are overcharged, for example, the pack can
fail. Unlike measuring the gas in a tank, it can
be tricky to monitor the exact amount of charge
in a cell. So battery makers often include more
cells to provide a margin of safety, as a hedge
against both running out of power and
overcharging the batteries. The pack makers are
developing better electronic equipment and
algorithms for measuring charge, which could
allow them to use closer to the bare-minimum number of cells.
Even as the new battery packs are being tested,
GM is developing the rest of the vehicle,
especially making sure that it meets targets for
weight. Ultimately, Gray says, there could be
tradeoffs between vehicle weight and battery
size, depending on how the tests go. There's even
a chance that expectations for the battery pack's
lifetime could be lowered if necessary, although
she emphasizes that the goal now is to have
battery packs with 10-year lifetimes.
In June 2008, after analyzing the data from a
year of testing, GM will evaluate if the
technology is where it needs to be and pick a production supplier, Gray says.
WHAT'S IN A NAME?
Last week, GM's Vice Chairman Bob Lutz was on "On
Point," a radio show by Boston's WBUR
You can listen to it online or download the
podcast. Interestingly, as have other GM
representatives, Lutz goes out of his way to say
""We don't know how big this can be yet but it is
a breakthrough car [The Chevy Volt] because it's
not a plug-in hybrid. This vehicle is an electric
vehicle. It's driven electrically; it has a small
gasoline engine that can be used like an
emergency generator set if you run your batteries
down to generate more electricity. We're shooting
for an all electric range of 40 miles including
freeway driving at 70 miles an hour. This thing
will have a top speed of 100 miles an hour so it
will be a fully functional automobile."
Clearly, someone at GM has decided that "EV"
sounds better than "PHEV." In the wake of this
show comes one of the stories we find both
amusing and very encouraging. "PHEV" has always
been awkward -- it describes the feature rather
than the benefit. (Like a "9-inkjet printer"
instead of a "photo-quality printer.") Many
people have tried other names but none have
stuck. We believe that when the marketing people
starting paying attention, PHEVs will make even
faster progress in gaining consumer interest. In
that light, we're delighted the Detroit Free
Press's columnist raises the issue.
The car above is: A: A hybrid B: An electric C: You tell me
MARK PHELAN | BEHIND THE WHEEL June 10, 2007
What's in a name?
Plenty if you're talking about the Chevrolet
Volt, which General Motors would like to put on
the road in a few years. It's been called
everything from the environmental breakthrough
that could redefine GM to a transparent marketing ploy.
The Volt is such a different kettle of fish that
around the newsroom, we can't even agree on how
to describe its propulsion system, which combines
big batteries with a small gasoline engine. The
gas engine charges the batteries, but you can
also charge them by plugging the Volt into a wall outlet.
Depending on how far you drive, gasoline
consumption ranges from zero -- pure electric
power up to 40 miles -- to 50 m.p.g. -- what
you'd get from a single tank of gas on a long
continuous drive with no stops to charge the batteries from an outlet.
GM appears to be serious about building the Volt,
although the die-hard skeptics dismiss it as a
marketing gimmick. They think GM cooked up the
idea to look environmentally aware while it pumps
out a few hundred thousand Hummer H2s.
Whether the idea works or not -- the technical
hang-up is developing a powerful and
sophisticated new kind of battery -- we're going
to be talking and writing a lot about the Volt over the next few years.
That's why we have to figure out what to call it.
Existing terms don't fit, and I'm looking for suggestions.
Here are the names we're stuck with today, and my handicap on them:
Hybrid. Won't do. Technically, only electricity
powers the car when you put your foot on the
pedal. The Volt's system would be far more
elegant and efficient than current hybrids, which
essentially carry around two drivetrains, one
electric and one internal combustion.
Plug-in hybrid. Accurate, but a loser. The name
combines the worst attribute of electric cars --
"You mean I have to plug it in?" -- with a
ho-hum, nothing-to-see-here sense that it's just another hybrid.
Series hybrid. The engineer's choice, which is
all you have to know about what's wrong with it.
It has the virtue of accuracy -- the electric and
gasoline systems work together, rather than as
separate-but-equal systems in current parallel
hybrids. That's swell, but I write about this
stuff all the time, and even I can't keep the
difference between series and parallel hybrids straight.
Electric car. Call out the truth squad. The
gasoline generator may be small and
extraordinarily efficient, but it's there, and it
allows the Volt the long cruising range no pure electric car could offer.
Extended-range electric vehicle. GM's term of
choice has all the zing of calling a wedge of
6-year-old Gouda cheese "stale milk by-products."
Too long and boring for the vehicle that might be
the next big thing. It's got some chops as an
acronym, though. "E-rev" sounds fast and slick
and modern. The downside is continually explaining what it means.
For the moment, at least, the Free Press has
decided to call the Volt electric-powered or
electric-drive. Neither of those exactly sings
the body electric, though, so come up with
something that crackles like a Tesla coil and drop me a note.
Contact MARK PHELAN at 313-222-6731 or phelan@....
How do you think the Volt should be described?
Leave a message in the forum by clicking below or
e-mail me a note at phelan@... with
your suggested name and a brief description of
why you think it captures the essence of what makes the Volt go.
I can't promise to use any of them, but we'll
print the most entertaining and interesting in this space next week.
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Felix Kramer fkramer@...
Founder California Cars Initiative
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