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Quote from GM website as of 09-24-2008 provided by member GMUSA. Thank you for the update.

"Unlike traditional electric cars, Chevy Volt has a revolutionary propulsion system that takes you beyond the power of the battery. It will use a lithium-ion battery with a variety of range-extending onboard power sources, including gas and, in some vehicles, E85 ethanol to recharge the battery while you drive beyond the 40-mile battery range."



Link: http://www.edmunds.com/insideline/do/News/articleId=132112

DETROIT — Remember when we wrote that the 2011 Chevrolet Volt would be able to run 40 miles on pure electric power and then fire up an onboard four-cylinder engine to recharge the batteries?

Turns out, that's not at all true.

In contrast to popular (and our) impression, once a driver uses up his 40 or so miles of electric power, the 1.4-liter gas engine generates electricity to power the electric drive motor, but does not recharge the batteries. After the 40 or so miles, the battery becomes 400 pounds of uselessness, at least until the owner can plug the car into the electrical grid for a recharge. This means that regardless of how far one drives the Volt, the driver will only ever get up to 40 miles of electric-only range.

Our confusion and that of much of the media corps might have to do with the fact that the company once wrote this: "When the battery is depleted, a 1-liter, three-cylinder turbocharged engine spins at a constant speed, or revolutions per minute (rpm), to create electricity and replenish the battery."

That was from a press release written for the 2007 Detroit Auto Show, where the Volt concept was unveiled. A release from the day of the production prototype's reveal reads, "a gasoline/E85-powered engine generator seamlessly provides electricity to power the Volt's electric drive unit while simultaneously sustaining the charge of the battery." And by "sustaining" GM says that it means only that no additional power is drained from the batteries. Get it?

What this means to you: It's not a deal-breaker and if you travel less than 40 miles per day, it won't make any difference. But for the record: The Volt's gas engine will not recharge its batteries. — Daniel Pund, Senior Editor, Detroit


MORE VOLT NEWS:

http://www.autonews.com/apps/pbcs.dll/article?AID=/20080923/ANA02/809239978/1128


Senate OKs Volt-friendly plug-in tax credit


Harry Stoffer
Automotive News
September 23, 2008 - 6:35 pm ET


WASHINGTON -- General Motors' hopes for a $7,500 federal tax credit to help it sell plug-in hybrid Chevrolet Volts may soon be realized.

The Senate this evening passed a complex and wide-ranging tax bill, covering everything from extension of credits for wind energy producers to expanded exemptions from the alternative minimum tax.

Riding along is a small provision creating a new tax credit for buyers of plug-in electric vehicles – none of which is on the market yet. The credit would start at $2,500 and rise to as much as $7,500 for a light-duty vehicle, depending on battery capacity.

A buyer of the Volt would appear eligible for the maximum.
 

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Re: IL Corrects Volt Story: Batteries Will NOT Charge When Driving

I thought everyone knew this?
 

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Re: IL Corrects Volt Story: Batteries Will NOT Charge When Driving

So basically after 40 miles the Volt becomes a basic, ordinary high mileage car? I.E., no gas motor off below 25 mph? If this is correct, this is a huge flaw IMO.
 

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Re: IL Corrects Volt Story: Batteries Will NOT Charge When Driving

so in other words basically the car is running on the 1.4 after 40miles,
so if you are using the car for long drives its not that much different from a normal hybrid.

surely after the 40miles, since the engine runs at a constant rpm it can recharge the batteries when the car is driving slow or stopped
 

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Re: IL Corrects Volt Story: Batteries Will NOT Charge When Driving

This is not what I had been thinking. It was my impression that the engine did indeed "charge", as in replenish, the battery.


Also, what about that 3 cylinder thing. I though it was gonna be a small 4 cylinder?


.
 

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Re: IL Corrects Volt Story: Batteries Will NOT Charge When Driving

We've discussed this before. This is the closest to a confirmation I've ever seen. It almost seems like MonaroSS was the one that argued it won't ever charge back up with the gas engine. The reasoning was it will only add to the charge/discharge cycles. If you drive much farther than 40 miles on a regular basis then if the batteries are charged up with the gas engine it creates another charge cycle. Limiting the charge cycle to a plug in environment limits most people to 1-2 charge cycles per day which should increase battery life. I recall the discussion got pretty heated.

Lutz did say something more recently that seemed to go against this however. I don't remember when he said it but I recall him saying that it would be smart enough to know when you were going home and not bother to charge up the batteries. Using GPS it would keep track of where you typically charge the car and if you were heading to that location it would leave the batteries in a lower state of charge when you arrive to minimize gas use and maximize battery use. I suppose this may be true even if the gas engine never fully charges the batteries. Maybe it keeps it in a 30-50% range and will allow it to drop to 30% as you approach home? We'll have to wait and see.
 

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Re: IL Corrects Volt Story: Batteries Will NOT Charge When Driving

It still has electric motors providing 100% of the thrust.
So basically the gas motor is like one big alternator that provides power to the electric motors but doesn't charge the batteries? Sorry, I am really confused on how this system is suppose to work. :D
 

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Re: IL Corrects Volt Story: Batteries Will NOT Charge When Driving

I thought everyone knew this?
I thought so too... Whats new here?
 

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Re: IL Corrects Volt Story: Batteries Will NOT Charge When Driving

Drive 40 miles on power that came from your home and after that you're gettin' ~50mpg.

Thus, drive 60 miles per day and you're getting ~150 mpg (hence the reason GM was advertising 150mpg). How many people drive more than that?
 

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Re: IL Corrects Volt Story: Batteries Will NOT Charge When Driving

How about regen braking? Is that not happening? And I thought the engine would be running at constant RPM -- how would that work if it is not buffering energy in the batteries?
 

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Re: IL Corrects Volt Story: Batteries Will NOT Charge When Driving

oh so very confusing...it just goes to show how easy it is to get the wrong information. there is a simple solution to this...in the future, don't talk circles around the truth. just tell it to the public like your telling a 7 year old, that way everyone will understand.
 

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Re: IL Corrects Volt Story: Batteries Will NOT Charge When Driving

Daniel Pund, Senior Editor, is an idiot media puppet. He probably thinks the VOLT concept is a coupe!
 

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Re: IL Corrects Volt Story: Batteries Will NOT Charge When Driving

this doesn't match the press release which talked about keeping the batteries between 30% and 80%...uhhhh riiighttt mr. journalist.
 

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Re: IL Corrects Volt Story: Batteries Will NOT Charge When Driving

Link: http://www.edmunds.com/insideline/do/News/articleId=132112

DETROIT — Remember when we wrote that the 2011 Chevrolet Volt would be able to run 40 miles on pure electric power and then fire up an onboard four-cylinder engine to recharge the batteries?

Turns out, that's not at all true.

In contrast to popular (and our) impression, once a driver uses up his 40 or so miles of electric power, the 1.4-liter gas engine generates electricity to power the electric drive motor, but does not recharge the batteries. After the 40 or so miles, the battery becomes 400 pounds of uselessness, at least until the owner can plug the car into the electrical grid for a recharge. This means that regardless of how far one drives the Volt, the driver will only ever get up to 40 miles of electric-only range.

Our confusion and that of much of the media corps might have to do with the fact that the company once wrote this: "When the battery is depleted, a 1-liter, three-cylinder turbocharged engine spins at a constant speed, or revolutions per minute (rpm), to create electricity and replenish the battery."

That was from a press release written for the 2007 Detroit Auto Show, where the Volt concept was unveiled. A release from the day of the production prototype's reveal reads, "a gasoline/E85-powered engine generator seamlessly provides electricity to power the Volt's electric drive unit while simultaneously sustaining the charge of the battery." And by "sustaining" GM says that it means only that no additional power is drained from the batteries. Get it?
Sorry, but no I don't. It may be true that the engine never charges the battery, but therefore the battery is not "sustained" after 40 miles, either.

We know the engine can't get it done alone, or we'd not be hearing about a finite 600 or so mile total range. Meaning, once the 40 miles of battery-only propulsion is done, the engine and the battery are working together. If the engine were sufficient to propel the car and "sustain" a constant battery charge from 40 miles onward, then the car wouldn't have any 600 mile limit -- it'd be like the energizer bunny, going and going so long as fuel's in the tank. Therefore, I think this guy's missing the point. The battery must indeed lose charge after 40 miles. The remaining charge after 40 miles is enough so that, when accompanied by the engine's power generation, the car goes about 600 miles. When the battery is done, so is the trip.

One would think that the batteries are indeed getting charge from the engine after 40 miles... Because at times the electricity needed for propulsion will be less than what the engine can deliver, so the battery becomes a reservoir. And regenerative braking would have to add juice to the battery otherwise be lost. But that may be the news ... that the engine never adds anything to the battery and there are no supplemental regenerative systems. The engine and battery power are isolated. In which case, the engine will never add electric-only range to the car. It's 40 miles and no more. Even if you park the car after 40 miles with the engine on, the system may not be programmed or even wired to restore the battery for any additional electric-only range.

And here's where I'll make an educated guess ... the reason they'd do it that way is to extend the life of the battery, which is already the weakest reliability link on the car.
 

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Re: IL Corrects Volt Story: Batteries Will NOT Charge When Driving

this doesn't match the press release which talked about keeping the batteries between 30% and 80%...uhhhh riiighttt mr. journalist.
Sure it does. When the battery reaches 30%, it will start up the engine and will cease using the battery to power the electric motor. Then when you plug it in, it will charge the battery to 80%.

The remaining charge after 40 miles is enough so that, when accompanied by the engine's power generation, the car goes about 600 miles.
GM reduced the size of the fuel tank so it will be more like 360 miles.
 

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Re: IL Corrects Volt Story: Batteries Will NOT Charge When Driving

This is something that has always been known to those who have been following the car's development closely. That said, I do still hold out that there WILL be times when the engine would be able to shut down. That situation will be mountain driving. The batteries range will be altered somewhat by how much regen it receives. The power in regen mode needs to go somewhere, and that will be the battery.

If you are easy on the vehicle going up a hill, it is entirely conceivable that you'll get plenty of extra charge back into the system on the downhill side. As I've stated in a previous posts, I witnessed this very same situation in my '03 Prius. Toyota maintained tight controls on battery charge as well. Still on extended downhill stretches of highway, regen would be sufficient to bring the battery above the softwares normal high limit. In my case, the battery symbol on the video game display would go solid turqoise, and the car's software would then begin using the excess power to propel the vehicle.

The Volt will no more be exempt from physics than the Prius. If the battery SOC gets high enough, the system should conceivably shut down the engine, to allow the car to use this "excess" power to run in EV mode. These situations will however, NOT be considered in the normal range of driving for the vast majority of its owners.
 
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