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Discussion Starter #1
I found this article on the GreenCarCongress web site:
http://www.greencarcongress.com/2008/04/gm-provides-sna.html#more

Several interesting tidbits:
"Provide sufficient power to accelerate the vehicle from 0 to 60 in 8.5 seconds; deliver passing capability; and deliver “predicted driveability”."
So again the 8.5 seconds number, not the 9 seconds, or Lutz's 7 seconds number. I'm not sure what the predicted driveability means.

"Provide sufficient energy to support a 40-mile all electric range under city and highway driving conditions."
First time I've seen 40 mile range on highway driving.

"Although the pack is sized overall at 16 kWh, GM plans to only use 8kWh in operations—i.e., a state of charge depletion window of around 50% (the pack won’t be charged fully to 16 kWh, because with a full pack, the first regen event would begin overcharging the battery). That 8 kWh needs to be deliverable at the end of the battery’s 10-year life, so GM is providing itself with a buffer with the 16 kWh pack."
If this is right, then at the end of the 10-year life the pack would no longer have a 80% to 30% cycle, but a deeper one to compensate for the degradation of the pack.

"With future iterations of the powertrain, GM might begin expanding the SOC window, or also begin implementing minor changes in the batteries."
Makes sense to vary the SOC window and see how it affects the battery life.

"GM has yet to finalize its selection of the combustion engine component of the power train, although the engine will be from its Family 0 of European small-displacement engines (1.0-, 1.2- and 1.4-liter)."

"GM is opting for a smaller fuel tank than originally conceived to reduce vehicle mass. The tank under consideration will still provide a 400-mile combined range, and GM decided to do as much as possible to ensure its 40-mile all electric range rather than go overboard in other areas, such as extended vehicle range."
I think GM is fixating too much on that 40 mile range, I think they could have made the pack slightly larger, or provided two versions, with the base model having a smaller electric range.
 

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Discussion Starter #2
Hmm, interestingly the yahoo article has a different opinion:
http://news.yahoo.com/s/nm/20080404/bs_nm/gm_volt_dc_1

"Meanwhile, GM engineers are counting on braking to capture energy that will deliver some 20 percent of the power needed for the Volt's 40-mile battery range. Without any braking -- in perfectly traffic-free highway driving -- the range would be closer to 32 miles, GM engineers said."

This statement does not make much sense, as you never recapture all of the energy. I think they mean that driving at or below 35 mph Volt can do 40 miles, but if you go at highway speeds, your range will be shorter.
 
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