Aug 24

NEW FACT: Chevy Volt Generator Starts When Battery Power Hits 50%, Stops Again at 80%

 

a123_batt_80.jpg

After a lengthy and healthy discussion about costs of driving the Volt we needed to know at what battery state of charge (SOC) the onboard generator would kick in. GM was kind enough to let us know that was intended to be 50%.

The next question to arise was that once the generator started at what SOC would it stop again as the car continued to drive.

Once again GM has been very helpful and informative and tells us the answer is 80%.

So what do these numbers mean? Mainly it tells us they wish to be very conservative with the batteries. Although A123 Li-ion cells are very robust and can handle repetitive deep discharges to below 20% and up to 100% again, up to 7000 times, GM clearly doesn’t want to take any chances with this very expensive (and possibly leased hardware). By keeping it in this limited range, the hope will be increased reliability and longevity I would have to assume.

Lets see what happens when one drives the Volt.

For the first 40 miles, as we’ve discussed, the battery will drain from full (16 kWh energy) to 50% (8 kWh), this 8 kWh will cost you roughly 85 cents in electricity. If you drive that distance or less, NO GAS.

If you keep driving, the generator will start. It will generate 53 kW of electricity. It needs to restore the pack by 30%, which is 4.8 kW, that would take ~5.4 minutes if the generator was only charging the battery. But at the same time, as the car continues to drive, the battery would continue to drain, so the generator would have to run longer.

GM estimates that in this condition, the combustion engine would provide 50 mpg efficiency.

From what engineering experts in the PHEV/EV field tell me, the battery pack, electric engine, and generator are all on the same bus (not yellow or greyhound folks), which means that one can have current flowing into the battery from the generator at the same time it is leaving to run the powertrain.

This is great stuff, and an engineering process never before witnessed by humankind. Let’s hope it works.

In the coming weeks GM will have the Volt “mules” (cobbled-together, rough and ugly engineering experimental prototypes) up and running with the first gen A123 packs (and CPI). Then these issues will be testable under driving conditions.

Right now, as per Rob Peterson of GM, “the engineers are still working out the optimum charge cycles and control systems”. As per Bart Riley of A123, “The key will be to achieve the life target for the battery across the all operational requirements (temperature, cycling, storage, SOC range)”.

Remember folks, you just can’t get this stuff anywhere else!

This entry was posted on Friday, August 24th, 2007 at 7:21 am and is filed under Battery, Electric Motor, Engineering. You can follow any responses to this entry through the RSS 2.0 feed. Both comments and pings are currently closed.

COMMENTS: 106


  1. 1
    Tim

     

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    Aug 24th, 2007 (9:29 am)

    More GREAT information.

    Thanks, Lyle!


  2. 2
    Estero

     

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    Aug 24th, 2007 (9:47 am)

    Lyle,

    You said it again — the possibly exists that the battery pack could be leased hardware. Can you ask GM about this?

    If the has the option to purchase or lease, that is OK. But, if the battery pack is ONLY going to be available through a lease agreement, then GM is likely to lose a significant customer base from the comments elsewhere on this forum. That includes me!

    I typically keep a car for several years and drive it over 100,000 miles before trading or selling it outright. My current car, for example, is a 1999 DeVille with 179,000 miles which I purchased new in Aug 1999. Even though my car is now 9 model years old, it is still in top notch condition because it has always had loving care and been well maintained.

    My plan is to do the same with a Volt and I simply do NOT want to deal with lease issues for all those years!


  3. 3
    Estero

     

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    Aug 24th, 2007 (9:58 am)

    Oops, bad grammar! The 1st sentence in the 2nd paragraph should have said:

    If the purchaser has the option purchase or lease the battery pack, that is OK…


  4. 4
    Nick D

     

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    Aug 24th, 2007 (10:01 am)

    Does anyone know if the IC engine and electric motor will have seperate odometers as well as one for the vehicle as a whole?


  5. 5
    OptimisticMF

     

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    Aug 24th, 2007 (10:07 am)

    Probably something to measure hours of operation for the generator and an odometer for the electric drivetrain???

    Anyway, GM should make the lease/buy optional. If you want to lease the battery pack, then you might as well lease the vehicle. Since the battery will likely be the most expensive and “iffy” component of the vehicle, GM could create a very robust certified, pre-owned market by taking in leased vehicles, replacing the battery and re-selling them.

    I am typically a “buy and hold” guy like Estero, but for a new concept like this, I have to think that they will only improve it in the first 2-3 years.


  6. 6
    Mike

     

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    Aug 24th, 2007 (10:13 am)

    If I understand correctly, the battery drains only 50% @ 40 miles drives, does that mean the Volt will be able to go further than 40 miles before a recharge? The reason that I ask is that I have a 27 mile one-way commute (total of 54 miles per day) and a limit of 40 miles before charging will prohibit me from buying the Volt. But if I can push it 14 more miles without major damage then I am good to go.


  7. 7
    Estero

     

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    Aug 24th, 2007 (10:14 am)

    Since the IC engine will turn on/off based upon the battery state of charge (SOC), it might be better to measure the IC engine in HOURS (like aircraft engines) rather than in MILES with a separate counter for the IC engine ON/OFF cycles.


  8. 8
    Brian

     

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    Aug 24th, 2007 (10:16 am)

    Mike:

    The Volt’s range is 650 miles. You will have no problem on your commute. The gas generator will turn on at some point to run the motor and recharge the batteries.


  9. 9
    Michel

     

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    Aug 24th, 2007 (10:18 am)

    Seems to me that one of the easiest ways to improve the battery life would be to have the current going directly from the motor generator (with excess going to recharge the battery), instead of always having the current coming from the battery!

    Not only would this improve the batteries lifecycle, but it would also allow a lower SOC before the generator would have to kick on which would also allow for a potentially longer driving distance.

    I’m thinking that with the A/C running (or the heater in winter) we’re going to need more than a 40 mile EV only range (if that range is based on driving without A/C or heat! Lowering the SOC would seem to be necessary to also keep the quantity of batteries to an affordable level.


  10. 10
    Estero

     

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    Aug 24th, 2007 (10:26 am)

    GM has probably included the heating and A/C into all their Volt equations. I could be wrong on this, but at this time I’m not the least bit concerned about these issues.


  11. 11
    Steve

     

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    Aug 24th, 2007 (10:27 am)

    I agree that the LEASE issue can be a deal killer… I buy, maintain, love, and hold.
    I do not lease. I also believe that those
    who want a “Green” or Eco friendly car have
    the same values:
    * Fiscal Conservative
    * Ecological Progressive
    * Rational Decision
    * Personal Control.
    They are not to be led into unsound personal purchase decisions, although they will pay a premium (limited) for the chance to live their values of reducing Global Warming and
    slowing the depletion of the earth’s resources. They will put solar panels on their roof to power their vehicles even though this costs more than coal fired
    electricity. They are focused on doing the right thing for the long term and have
    a view which is not USE and Throw Away.
    They are consumers with a small “c” rather
    than CONSUMERS with all caps.
    They reserve the Capital “C” for Conserve.
    Steve


  12. 12
    Estero

     

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    Aug 24th, 2007 (10:29 am)

    Michel said – Seems to me that one of the easiest ways to improve the battery life would be to have the current going directly from the motor generator (with excess going to recharge the battery), instead of always having the current coming from the battery!

    Doesn’t that defeat the whole concept of a series hybrid? Or, am I missing something here?


  13. 13
    voltman

     

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    Aug 24th, 2007 (10:38 am)

    So if I am one mile from home and sitting in traffic, my generator will kick on and nearly recharge my battery to full? The generator should just go to 60% not 80%.

    What happens if I have no gas in the tank? Will it keep going or just die at 40 miles even though it can go more?


  14. 14
    Brian

     

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    Aug 24th, 2007 (10:41 am)

    Estero:

    You are right, that’s how it works. See Lyle’s original post where it says the motor, generator, and batteries are all on the same bus. That means it works just the way you described.


  15. 15
    voltman

     

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    Aug 24th, 2007 (10:42 am)

    50% oversizing of the battery is kinda retarded. A123 batteries can DEEP discharge 7000 times, thats 21 years. In 21 years these batteries will be the size of a book and cost a hundred bucks.

    What was the cost of a computer in 1986? And now?


  16. 16
    Jon

     

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    Aug 24th, 2007 (10:45 am)

    Here’s my take on leasing…if the leasing included a promise to take the battery back and recycle it (cradle to cradle design), that would be a great comittment from GM. If you understand the idea of products needing to be designed for recyclability, then the idea of GM taking my Volt back and making another one from the component pieces would be laudable.

    My question for the moderator: how recyclable will this car be?


  17. 17
    Dan

     

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    Aug 24th, 2007 (10:46 am)

    Great Post, begs a question though: If I drive 41 miles a day and “force” the recharge, then I get little to no advantage with my home electric charging. Right?

    In this scenario, the Volt will always charge itself and not use my home electric. I would be pulling into the driveway with the generator running and charging me back up to 80%.


  18. 18
    Mike

     

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    Aug 24th, 2007 (10:57 am)

    In reply to Dan’s comment about not getting the full advantage of the home re-charge because the generator will force a recharge at 80%.

    I have two suggestions.

    1. The Generator should stop if it detects an alternative re-charge (as in a home re-charge).

    2. There should be an easy manual cut off switch in the car to override the on-board generator for just such a condition as Dan stated.


  19. 19
    Michel

     

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    Aug 24th, 2007 (11:18 am)

    Estero says: ‘Doesn’t that defeat the whole concept of a series hybrid? Or, am I missing something here? ‘

    Nope. The driving motor allways runs on electricy so it would still be a series hybrid. My suggestion was for a way to improve the life cycle of the battery and thus allow a lower SOC so that more miles could be driven using just battery mode.


  20. 20
    Brian

     

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    Aug 24th, 2007 (11:19 am)

    Dan:

    Also remember that GM claims the Volt will get 50 mpg on the gas generator, so it is still better than a regular car (about the same as the Prius, with undoubtably better styling). So it wouldn’t be the end of the world to recharge a little bit with the generator before you plug in.


  21. 21
    Michel

     

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    Aug 24th, 2007 (11:22 am)

    I also agree with what others seem to be suggesting here, that the driver be allowed to override when the battery begins it’s recharge cycle. This would also allow those of us that have a slightly longer commute to still be able to make it back home using only battery contained electricity then plug in and get the most out of grid electricity instead of having the engine kick in and reduce the plug in benefit.


  22. 22
    Estero

     

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    Aug 24th, 2007 (11:23 am)

    voltman said – What was the cost of a computer in 1986? And now?

    There is no question that the cost of the Volt battery packs will come down over time with 1) the economies of scale, 2) the development of new materials and 3) engineering solutions. But, I’m not sure it is valid to make a comparison with the cost computers in 1986. It is like comparing apples to oranges.

    The lithium ion batteries represents a tremendous challenge. They might very well be the best solution over the short term, but their continued use over the long term is a very big question. Here is how I see it!

    The prospects are good for the lithium ion battery in terms of improved power, extended life and safety. But, the achilles heel of the lithium ion battery is its size and weight. Is there anyone out there that is predicting the lithium ion battery size or weight will be reduced in the future. If so, I’m not aware of it. So, from my perspective, the only hope for reduction in cost for the lithium ion battery is the economies of scale.

    The situation is quite different for companies like Firefly Engergy who are developing new materials for batteries which show much promise in size, weight, power, life, safety and COST.

    My bet is companies like Firefly Energy will be the winner over the lithium ion battery over the long haul.


  23. 23
    Estero

     

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    Aug 24th, 2007 (11:26 am)

    Further, the best opportunity for reduction in the cost of battery packs lies more in other technologies than with the lithium ion battery.


  24. 24
    Darren

     

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    Aug 24th, 2007 (11:33 am)

    Just a thought about the 50% SOC before the generator kicks in. This is also probably a safety factor so that if you do run out of gas or don’t have any in the tank it prevents you from getting stranded and allows you to get the advertised 40 miles and then a safety buffer to recharge or get gas. If it ran to 20% or less at 40 miles you would be SOL if you didn’t have gas. Also for those that have access to a plug at work you could charge there even if it’s just enough to get the extra few miles to extend the electric range beyond 40 miles.

    And depending what the output of the generator would be it might be too high a voltage to run the motors directly so rather than have 2 converters they have opted for one converter to simultaneously charge the batteries and drive the motors. That’s how any piece of electronics I have ever used works.

    And I do remember that in a discussion GM mentioned that they are not required to factor AC into fuel consumption figures so running the AC would decrease the advertised mileage.


  25. 25
    Tim S

     

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    Aug 24th, 2007 (11:35 am)

    A lease is okay if it is not expensive and I can turn the dead batteries in for new ones.
    But I have a question.
    Picture this: It’s summer, raining, it’s dark outside. I have my high beams on, A/C, wipers, rear defrost, and radio all turned on.
    How far will the fully charged battery take me until the gas motor turns on?


  26. 26
    Sazqwatch

     

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    Aug 24th, 2007 (12:02 pm)

    Tim S Says: Picture this: It’s summer, raining, it’s dark outside. I have my high beams on, A/C, wipers, rear defrost, and radio all turned on. How far will the fully charged battery take me until the gas motor turns on?

    Tim…who cares? The gas engine will be getting 50 mpg. That blows away most any car on the road. If/when it kicks in, so what? You still saving lots of money and helping to curb pollution.


  27. 27
    Sazqwatch

     

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    Aug 24th, 2007 (12:04 pm)

    I can’t wait until they come out with a full sized truck hybrid with enough power to put a camper in the bed and still pull a boat. I’ll be first in line for one of those.


  28. 28
    Steve F

     

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    Aug 24th, 2007 (12:24 pm)

    Comment on the leasing the battery. I have never leased a car and also a “buy and hold” type of guy. Also I want to be one of the first to get a Volt. Only I realized that no matter how hard GM works to get all the bugs out, but because it is so new technology, there will be problems and issues with the first or second year of the the car. So maybe leasing a Volt for first 3 years may not be that bad. Then after three years purchase a new Volt and keep that for 10 years or longer.


  29. 29
    Mike Hanlon

     

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    Aug 24th, 2007 (12:31 pm)

    I am sooo pumped about the mules being tested. I can’t wait to hear the outcome.
    Go GM Engineers!!! Future heroes of ability to kick our dependence of foriegn oil!!!


  30. 30
    Seaquake2

     

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    Aug 24th, 2007 (12:46 pm)

    I might be doing my math wrong here but if the battry goes to 50% (40 miles) and it only recharges to 80%, does that mean that technically the battery can go around 120 miles? 80% – 50% = 30% so 30% = 40 miles. So 100%/30% is around 3 times so around 120 miles? If that is the case then i hope in the 2nd or 3rd and beyond generations of the volt they give us more then 40 miles!!! Cause 120 miles is pretty sweet!!!


  31. 31
    Matt986

     

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    Aug 24th, 2007 (12:52 pm)

    Tim, calculate like this:

    HIDs, such as the ones in my Porsche are 35W bulbs. Both would have a 70W draw on the battery. High beams usually use halogen bulbs, not HIDs, since HIDs take a second or two to ‘start up’. Calculate about 140W for that.

    Per another discussion, someone found that a window AC unit you’d see in a house or trailer home use about 1-1.4kW.

    Wipers probably won’t take more than a couple hundred watts.

    So, you’d probably be able to sit there with your AC on, your high beams on, and the wipers going for about, oh, 12 hours or so.

    As far as range, the reduction will be noticeable, but minimal. Probably a reduction in range of 5-8 miles?


  32. 32
    Dr. Dan

     

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    Aug 24th, 2007 (1:04 pm)

    Lease is good! I can always use more tax deductions!…


  33. 33
    Tim S

     

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    Aug 24th, 2007 (1:12 pm)

    Sazqwatch, I was only curious, that is all. I want this car so much, I am nurse maiding
    my 140,000 mile Elantra until 2010. My commute is 101 miles per day, but should
    be able to plug-in both at home and at work.

    Matt986, Thank you for your helpful reply. It seemed logical to me to lose some mileage, but 5-8 miles is pretty minimal. I hope that GM does this car right.
    It is really something the entire world (minus OPEC) needs.


  34. 34
    Dave

     

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    Aug 24th, 2007 (1:15 pm)

    Seaquake2 Says: “does that mean that technically the battery can go around 120 miles?”

    The 40 miles assumes that you have just recharged to 100% by pluging in to the electrical grid. So, if you’re out of gas, you can theoretically go 80 miles on battery alone. But then when you did get some gas, you wouldn’t be able to start the engine since the battery is totally dead.


  35. 35
    Matt986

     

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    Aug 24th, 2007 (1:16 pm)

    Tim, maybe with the threshold of the battery SOC at ‘discharge’ being at 50%, GM will allow it to cycle a little bit more to compensate for accessories?

    We’ll see what they do with it, but it would be nice to still get that 40 miles regardless of what extra stuff is running.


  36. 36
    Dan

     

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    Aug 24th, 2007 (1:26 pm)

    Hi Brian,

    You have a good point about the 50 MPG, but I was hoping for a car that ran on electric from my home, not electric from a gasoline generator.

    I predict that the visual clues as to when the generator will start will not be all that specific, so we’ll be guessing most of the time.

    If you guess wrong, then you burn gasoline. I doubt that you will be able to dissuade the car from charging once it starts.

    Oh well.


  37. 37
    Nick D

     

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    Aug 24th, 2007 (2:01 pm)

    It would be nice if they put a human interface in there that would allow you to charge based on estimated miles, if you were almost to 50% charge (“dead”) and were 4 miles from home you could tell the car somehow that you needed a charge to get you 5 more miles and it would charge that much.

    But with all the technology already in this car, some of these requests may seem petty. Maybe its something that they will see demand for in future models.

    Keep in mind that the average Joe who trades in his H2 for this thing probably does not care if he only gets 20% of his electricity from the grid.


  38. 38
    Tai

     

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    Aug 24th, 2007 (2:09 pm)

    Mike Says: \Mike Says: “I have two suggestions.

    1. The Generator should stop if it detects an alternative re-charge (as in a home re-charge).

    2. There should be an easy manual cut off switch in the car to override the on-board generator for just such a condition as Dan stated. ”

    This must surely be the case. If we parked the Volt in the garage and shut the door with the generator running, the garage would fill up with exhaust! It would only be a matter of time before somebody kills their dog, cat or worse! LOL (actually that’s not very funny) That just simply will not do…

    I’m sure GM has already thought of this.


  39. 39
    NeHigh

     

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    Aug 24th, 2007 (2:34 pm)

    First post for me. Anyway, what’s all this about how far the Volt will go after running out of fuel for the generator? I’ve been driving since 1973 and have never run out of gas. How hard will it be to stop and dump some liquid fuel in every three weeks?

    I think the Volt is the best compromise yet when it come to cutting our umbilical cord to the middle east. It’s not a perfect solution but it’s a good start. I will miss my manual transmission though.


  40. 40
    RB

     

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    Aug 24th, 2007 (2:42 pm)

    What is the source of the phrase “and possibly leased”? As the phrase has only shown up recently, I assume that it comes from some kind of guidance from GM.


  41. 41
    Nick D

     

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    Aug 24th, 2007 (3:27 pm)

    NeHigh: I think the discussion is actually refering to how to use the least amount of Gas, by maximizing the use of energy stored in the battery generated from the electrical grid as opposed to energy gererated from the IC engine.

    People are concerned that if they hit the 50% threshold the engine will turn on and completely charge the battery using gasoline (in other posts the time to top off the battery was estimated to be less than 6 minutes.) Then coming home to your garage with less gas and a fully charged battery, when the most desirable option would be to have the gas engine charge the battery only partially allowing the user to charge up the battery using electricity, not gasoline, or in my case ethanol.


  42. 42
    Mike G.

     

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    Aug 24th, 2007 (5:14 pm)

    GM doesn’t want to take any chances with the battery. Keep that in mind. A switch to turn of the generator isn’t likely if GM has anything to say about it. I just hope that there is a switch that will turn off the generator until you reach 50%! Sort of a reset button.

    This would allow you to tell the generator not to charge but wouldn’t risk damage to the batteries because the generator would override the switch when it reached 50% discharge.


  43. 43
    Paul M

     

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    Aug 24th, 2007 (5:19 pm)

    I am one of the individuals Nick D says will be concerned if I do not have some control over when the IC engine starts to recharge the battery. I do not want the engine to start and recharge my battery if I am close enough to my house to drive there electrically with only a slight decrease of the SOC below 50%. Even though I feel GM is treating their batteries too conservatively, what I think and want and what GM decides to provide are two different things.

    I would prefer to discharge the battery well below 50% SOC before the engine begins recharging it so as to maximize battery life as measured in numbers of recharges. The fortunate owners of the Toyota RAV4 EV are discharging their NiMH batteries below 20% and recharging them to at least 80%, and some of these batteries have driven their RAV4 EV’s well in excess of 100,000 without battery refurbishment.


  44. 44
    Hoang

     

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    Aug 24th, 2007 (6:30 pm)

    To the 40+ miles and recharge problem, I think they can add GPS so that the car knows when you are near your home or wherever you can plug it in( custom settings ), the generator will shut off and let the battery deplete to 50% or whatever level. Nowadays, $300 can buy you a good GPS. And I don’t think adding about $300 to the car’s price tag is that bad.

    My 2 cents


  45. 45
    kent beuchert

     

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    Aug 24th, 2007 (6:57 pm)

    I suspect that GM will have a “kill” switch to turn off the IC engine so that you can motor into the garage with the battery as close to the 50% mark as possible, so that you can fill the battery off the grid as much as possible.
    Just heard that the plug-in Dodge that they are using to test the “plug-in concept” (apparently the Dodge folks can’t grasp the notion) has a 220 voly input. Let’s all urge GM to do the same and allow both 110 and 220. Remember, with a 220V/50AMP circuit, you can stream 8 kilowatt hours worth of juice for a complete fill up in only 44 minutes. That means plug in after work and ready to go again after a short dinner. Could easily refill 3 times a day if schedule permits and get 120 miles of all-electric cheap travel. A 12,000 mile per year car averages 33 miles per day, a 15,000 mile per year car averages 41 miles per day.


  46. 46
    stormc

     

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    Aug 24th, 2007 (7:21 pm)

    I have an electric car. You guys should get off the 40 mile kick. The range on battery power depends on how you drive it. Jack rabit starts and high speeds will reduce it drasticly. On the other hand, driving conservatively will increase it.

    FWIW, I volunteer to test the beta model!


  47. 47
    Dave

     

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    Aug 24th, 2007 (7:38 pm)

    To everyone asking for a ICE kill switch:

    WHY?

    Yes, If you are only a few minutes from home, then you could probably get there safely on batteries alone. But if you are only a few minutes from home and the ICE kicks in, it will only be on for a few minutes. So what’s the big deal? You’re still running 95% on electricity. If this happens every day, then you might have to go to the gas station every 3 months. I could deal with that!

    If you did have a kill switch, and then forget to switch it back on, then you are stuck! The battery is dead. The ICE engine won’t start.

    Let’s keep this thing simple. If it’s made for us geeks, no one will want it.


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    Aug 24th, 2007 (7:55 pm)

    I think the 50% battery threashold is there for a reason. For example, if it gets really cold outside, 50% may change to 25%. Or what if you park your car for a month without charging, the batteries will drain during that time. I’m sure there are many other examples. The bottom line is that you always want to have enough juice to start the ICE engine. Engineering margins are there for a reason.


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    Aug 24th, 2007 (8:10 pm)

    I think a lease would actually SAVE us money compared to a complete buyout. Here’s why:

    1) The current tax credit for each PHEV is $4000-$6000 depending on your state. In 3 years when the Volt is release, the tax credit will probably be even more due to instability in the oil market, middle east, more terrorism, a pissed-off recently bombed Iran, etc. Having such a massive tax credit on a *leased* vehicle will be very attractive because you can put that cash toward the one you *buy* 2 years later.

    2) For all of the reasons listed above, oil will probably be more expensive than it is now so even a leased Volt would be more economical than a purchased Accord.

    2) Versions 2.0 and 3.0 of the Volt will be magnitudes better than version 1.0 (and that is saying a LOT because the Volt 1.0 is going to be amazing from so many aspects). 2.0 and 3.0 vehicles will last longer and be even more energy efficient and therefore be able to save us even more at the plug (screw the pump).

    So buying a 2.0 or 3.0 will, in the long run, probably SAVE us money as opposed to buying a 1.0


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    Aug 24th, 2007 (8:35 pm)

    I would expect that the production model of Volt will allow you to return home with a SOC around 20% to maximize the fuel savings of a PHEV over those of a HEV. To achieve this low SOC, the generator cycle should only boost the SOC by 10%. Such a recharge cycle should also increase the battery life in terms of aggregate kWh of charge. A123 claims 3,000 cycles at 100% DOD, which equates to 3,000 times the battery energy storage capacity, and 7,000 cycles at 80% DOD (20% to 100% SOC), which equates to 5,600 times the battery capacity.

    So what is the battery life in aggregate kWh when the generator recharge cycle runs from 20% to 30% SOC, with a nightly recharge to 100% SOC? Are there engine emission issues with an1.5 minute vs. a 4.5 minute generator cycle? Will you be able to buy a Volt with a different battery storage capacity tailored to your commute?


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    Aug 24th, 2007 (9:05 pm)

    Pete Says: “I would expect that the production model of Volt will allow you to return home with a SOC around 20% …”

    OK, let’s say I have 80K miles on the car, and then park somewhere I can’t plug in, and it’s really cold outside. Suddenly the 20% goes down to maybe 5% or less. At that amount of storage, the gas engine may not start.

    I’m sure there are many other operational requirements that dictate the 50% engineering margin. Remember in the original post from Lyle:
    As per Bart Riley of A123, “The key will be to achieve the life target for the battery across the all operational requirements (temperature, cycling, storage, SOC range)”.


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    Aug 24th, 2007 (10:05 pm)

    Stormc is right.

    40 miles is not cast in stone. If you drive leisurely, Volt may get 50 miles on batteries. Or maybe 30 if you have a lead foot.

    But one neat thing (not discussed yet AFAIK) is that GM can EASILY control the max power that can go to the wheels. So just in case someone from GM is reading this…

    Maybe GM could let the Volt run in one of two modes. The mode already described (with the generator operating between 50% and 80% SOC), could be called the “performance” mode. It uses all the power available, for when you want to impress your friends, or at least prove that a Volt is not just an awesome looking golf-cart.

    Also introduce an “economy” mode. In this mode, the generator could run between 20% and 50% SOC. Also, the amount of power available to drive the wheels would be reduced, say by 50% of max. The reduced power would both prevent lead-foot driving (more economy) and prevent Volt from being driven so as to completely deplete the batteries.

    It’s a simple enough solution (one toggle button) that even Grandma can use it. And it also lets you easily utilize (if you choose to) about twice as much grid electricity. Obviously, my percentages above were made up as an example. GM would need to conduct some tests to determine what values make sense. Who know … maybe even three modes: “Performance”, “Standard”, and “Economy”. I think Grandma could handle a button with three settings also.

    So what would this do for electric range?

    In economy mode (with reduced power usage as described above), the range from 50% of the battery capacity will probably be 50 miles, not just 40. And in economy mode, you can use 80% battery capacity before the charger kicks in. That would be 80 miles on pure electricity folks! I think it’s possible.


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    Aug 25th, 2007 (12:02 am)

    This is good and bad news because the battery pack will be a lot more expensive if it contains 80+ miles of electricity vs. 40. But obviously more EV-only range is a good thing for those who want to use a kill switch and run it exclusively as a pure EV. That kind of range is more than enough for an average commute, errangds, and some joyriding.


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    Aug 25th, 2007 (2:10 am)

    A kill switch? A GPS to kill engine (ICE) near home??? Back to reality!!! The car needs to be SIMPLE are DURABLE. A “no brainer” besides remembering to plug-in and un-plug! Remember “Who Killed The Electric Car” when they interviewed people off the street filling up their SUVs saying they don’t think EVs will work? People in general are scared of electric cars because they are “different” and different = scary right? :)

    1) General public fears the batteries will die in 3 years just like their laptop or cell phone battery. Who wants a $30K car that dies in 3 years? Smaller battery cycles *should* equal longer battery life. Let’s say they add your kill switch… you will arguably have to replace expensive batteries sooner and this will hurt future Volt sales. (Though, someone will probably make an aftermarket modification chip and sell online)

    2) Regular people (that don’t check this site daily like me) also fear the car will not start in the bad part of town or in extreme weather conditions i.e. below freezing. So 50% minimum charge = peace of mind. Peace of mind = sales! Sales = money for GM to make better Volts! “Econo mode” (previous posts) sounds cool, but the trade off may be less durability? (another idea for the mod chip)

    Once GM proves “different is good” the Volt will catch on like wild fire! Bravo GM!


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    Jean-Charles Jacquemin

     

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    Aug 25th, 2007 (2:23 am)

    OK Keith, I agree with all your arguments.

    May I add another one. People will not be scared if GM sells the Volt with a special warranty of complete mobily (like Toyota here in Belgium of 5 years and 100.000 miles).
    Both Opels that I own have a special all-in GM insurance that I bought with the cars valid until they reach 150.000 km (+/- 100.000 miles) and I ensure you that the service I get from the Opel deales is perfect (replacement vehicle, no discussion on parts, etc.)

    If this can be done for commun cars in Belgium, why not for the Volt in the US ?


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    Aug 25th, 2007 (9:01 am)

    Another option to manage battery recharge and believe is better than a manual kill button. By default Volt will start recharge at 50% and recharge to 80%. Have another option to set the range of the recharge cycle. Allow change recharge to start at 50% but stop at 60% or 70%. The result is if drivers just need a smaller recharge to get to home at a max of 60% then they have control over recharge and can max home plug-in charge. The good point is that it still handles drivers that mis-calculate the range or have different driving styles. If for example, it recharges to 60% but then they drive back down to 50%, then ICE would once again recharge to only 60% and then finally get home to plug-in. Then maybe when they turn it off for the night it reset to default 50% to 80% recharge. I think this would be better than some manual kill button that each driver would have to figure out and give impression on system complexity.


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    Aug 25th, 2007 (12:07 pm)

    My normal drive is 43 miles pr day total. If the charge starts 3 miles before I get home and I can’t stop it some how It will defeat the purpose of the car. I might as well buy a Yaris. I love the concept of the Volt and am ready to buy but If I can’t take advantage of the home charge it will be a deal killer for me.


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    Aug 25th, 2007 (2:31 pm)

    As Voltman and Steve F. mentioned, the batteries will become the same as cell phones. The first car phones took the entire passenger space in mid-1950s Cadillac (not to mention the Bat-Car), then bag phones, now you can hardly see them and they’re nearly free. I wonder why the generator can’t run like a taillight I had on my bicycle 40 years ago, rubbing a wheel on the tire made it work. Seems the car could charge itself through a reduction gear. This seems like simple technology from years ago. What’s the deal?


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    Aug 25th, 2007 (2:33 pm)

    CW, I think that’s an odd attitude. You MIGHT end up burning gas for 2 minutes, so you might as well just burn gas the whole way?

    I bet GM will make a couple different ‘modes’, and one will allow you to shut off the car completely, so that you’re not burning gas when you get to a destination just beyond that 40 mile range.


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    Aug 25th, 2007 (2:45 pm)

    “Let’s say they add your kill switch… you will arguably have to replace expensive batteries sooner ”

    That’s purely speculation. GM is just being ultra-conservative. They are also planning an active cooling system for LiFiPo batteries that may not even need it.

    The bottom line is if it’s got 80 miles of power in the batteries, the car is going to get hacked to access a the full range of charge whether GM likes it or not.


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    Aug 25th, 2007 (3:15 pm)

    Hi Matt 986,

    I think you missed the point. Let’s say that the car is fully charged. I drive 45 miles. When i get home the car will be charged near 80%. For the last 5 miles the car will try and charge itself using gasoline.

    Same thing the next day, and the day after. In this scenario, I only get to charge the car from my home electric for about 40% of the milage. The other 60% of the milage is being charged by the gasoline engine.

    That is more significant than just burning gas for 2 minutes.


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    Aug 25th, 2007 (4:53 pm)

    Dan, so you’re better off getting a Yaris? I understand what you’re saying, you get home almost fully charged, which doesn’t let you get much power from plugging in.

    Is getting a gas powered car a better solution? Even if the Volt ends up averaging about 50mpg?


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    Aug 25th, 2007 (4:59 pm)

    How about this for round trips a little more than 40 miles:

    You get to your destination, about say 24 miles away. That would leave you with about ~16 miles of range left. Imagine there’s either a mode or a way to have the generator run for just long enough to give you enough juice to get home?

    Would that be a good idea?

    How about even fully charging from the generator while you’re at a destination?


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    Aug 25th, 2007 (5:10 pm)

    Shouldn’t it be possible to run the generator at a level that would maintain the current level of charging. Basically only provide enough power to prevent the battery from discharging below 50% but not charge it any more than that. I would think it would be as simple as running the generator at lower RPMs.

    Perhaps the ICE could use an HCCI mode at this charging state as the ICE wouldn’t need to run under full load and could benefit from HCCI.


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    Aug 25th, 2007 (5:26 pm)

    pstoller,

    Running the generator at any other output level will result in off peak efficiency running. The amount of energy you’d get for the amount of gas you’d burn would be reduced.

    Incorporating HCCI may be possible, but it may increase the cost of the generator. One has to understand the phenomena of detonation to understand how HCCI works. Getting it to work in an engine is tricky. It has to be set up at the right speed, temperature, compression ratio, and the amount of air, the temperature of the air, and the octane rating of the fuel all have to be compensated for.

    The simpler and more cost effective solution is a generator that runs at one output – it’s most efficient.

    The better way to reduce the amount of gasoline you end up burning will have to come from being able to control when and how long it runs.

    I’d think perhaps a GPS interface where a trip could be planned and monitored, then running the generator can be controlled to get the best and most efficient use, maximizing the use of plug in recharging.

    I’d see it like this: You’d have a GPS system in the car with a touchscreen display. Set your ‘home’ location and your ‘work’ location, and set the route you normally take. If this is more than 40 miles, the vehicle calculates when the best time to run the generator would be, and for how much charge you would need to make it back from your destination. One off destinations could be programmed with a ’round trip’ option to let the computer know you’re going there and coming back.

    For other driving, a couple driver selectable modes would be good, as well as options to manually start the generator (to top off) or stop the generator (to prevent it from running when you’re close to being able to plug in).

    We’ll have to wait for GM to divulge how it will manage this system, whether or not it will have options like this, ‘modes’, or if it will just do it’s own thing, since for most of us, it will almost never have to engage the generator.


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    Aug 25th, 2007 (11:03 pm)

    CW Says:

    “My normal drive is 43 miles pr day total. If the charge starts 3 miles before I get home and I can’t stop it some how It will defeat the purpose of the car”.
    _________________________________________

    Turning the ignition switch to the “off” position will solve that problem.


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    Aug 25th, 2007 (11:30 pm)

    To begin, the 50% – 80% figures are preliminary, the numbers could change before production begins. Even the 40 mile EV range should be considered preliminary.

    Why start the range extender at 50%? Several reasons: Battery power is needed to start the range extender. The range extender is small, producing just enough power for steady freeway cruising, but additional power from the battery is needed for rapid acceleration – SOC could drop as low as 30% under certain circumstances. Power output from the battery drops dramatically below 50% SOC, extra power from the range extender assures consistant performance. Battery life can be shortened by deep discharge, preventing excessive discharge and overcharging dramatically improves battery life.

    Most of the power from the range extending generator goes directly to the motor, bypassing the batteries, as that is more efficient. The battery is recharged during regenerative braking, or when the range extender produces more power than the motor needs (slower speeds, downhill, tailwind, etc.) It is highly unlikely for the SOC to climb from 50% to 80% in just a few miles!

    While I’m sure someone may hack into the E-Flex controls to run longer in EV mode, it would almost certainly void the warranty, and might possibly even shorten the life of the battery pack. Hardly worth it. On the other hand, GM might decide to offer extra battery capacity as an option, to increase range and power.


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    Aug 25th, 2007 (11:36 pm)

    Dave,

    Based on the reliability of electric motors and the low temperature performance of Li-ion batteries, your concern about being stranded after parking in cold weather is not warranted. However, there would be a concern about being stranded due to design flaws which can happen with any new product. This is the reason that some people will wait for Volt II.

    The 50% engineering margin is far too much and, for a 40-mile all-electric range (AER), it would require 16 kWh of battery capacity or 60% more than the 10 kWh needed with a 20% margin. A 20% margin is quite sufficient for over 15 years and 250,000 miles of battery life based on A123’s claim of 7,000 cycles at 80% depth of discharge (DOD) – from 100% to 20% SOC. The cost of a 60% increase in expensive battery capacity would certainly be passed on to the consumer and would severely impede the Volt’s market acceptance much to the delight of Toyota, the oil companies and luddites in GM.


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    Aug 26th, 2007 (6:59 am)

    CM says: ‘Most of the power from the range extending generator goes directly to the motor, bypassing the batteries, as that is more efficient.’

    I had offered this previously as a suggestion of a way to improve battery life cycle, however several folks have noted that this is not the current plan.


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    Aug 26th, 2007 (3:33 pm)

    # Tim S Says:
    August 24th, 2007 at 11:35 am Quote

    A lease is okay if it is not expensive and I can turn the dead batteries in for new ones.
    But I have a question.
    Picture this: It’s summer, raining, it’s dark outside. I have my high beams on, A/C, wipers, rear defrost, and radio all turned on.
    How far will the fully charged battery take me until the gas motor turns on?
    ==================================

    Is this common summer weather where you live?
    If not, why does it matter?

    Furthermore, assuming it isn’t a perpetual summer, why does it matter if this is your mileage situation for 3 months or so out of 12?

    Which proposition would be better than the Volt? Furthermore, why does it matter if the engine comes on for two or three miles a day (assuming these conditions)?

    Is the engine never to come on at all–ever, in the life of the car?

    If you think so, why not buy an electric car instead?

    40 miles is good enough on the vast majority of days for the vast majority of people. It may even be more than enough.

    You can’t always get what you want every day all day.


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    Aug 26th, 2007 (4:48 pm)

    # Tai Says:
    August 24th, 2007 at 2:09 pm Quote

    Mike Says: \Mike Says: “I have two suggestions.

    1. The Generator should stop if it detects an alternative re-charge (as in a home re-charge).

    2. There should be an easy manual cut off switch in the car to override the on-board generator for just such a condition as Dan stated. “

    This must surely be the case. If we parked the Volt in the garage and shut the door with the generator running, the garage would fill up with exhaust! It would only be a matter of time before somebody kills their dog, cat or worse! LOL (actually that’s not very funny) That just simply will not do…

    I’m sure GM has already thought of this.
    =======================================

    Switches, buttons, schlitzes, muttons, my foot!

    (Some people need to try to understand what it is they are getting excited about, before they get excited. I guess that is what this forum is for.)

    Where are some of these ideas coming from?

    The car is a normal car with a normal engine (albeit at constant RPM). The engine has been formally called a range extender.

    What that means is that after the first 40 miles of your 650 mile trip, the engine will come on in order to re-charge the batteries because that is the only source of electrical power left at that point.
    The car runs on electricity only, remember?

    It is not a Honda Generator that just comes on willy-nilly to charge the batteries at all times of day and night. It is an engine, whose sole purpose is to keep you running after 40 miles on the road–not to simply “charge the battery” (although that is what it will have to do).

    Therefore, like all normal car engines, it will turn off when you pull in to your garage and turn off the car (at the 649 mile mark or 41 mile mark or whatever mile mark).


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    Aug 26th, 2007 (4:59 pm)

    # Paul M Says:
    August 24th, 2007 at 5:19 pm Quote

    I am one of the individuals Nick D says will be concerned if I do not have some control over when the IC engine starts to recharge the battery. I do not want the engine to start and recharge my battery if I am close enough to my house to drive there electrically with only a slight decrease of the SOC below 50%. Even though I feel GM is treating their batteries too conservatively, what I think and want and what GM decides to provide are two different things.

    I would prefer to discharge the battery well below 50% SOC before the engine begins recharging it so as to maximize battery life as measured in numbers of recharges. The fortunate owners of the Toyota RAV4 EV are discharging their NiMH batteries below 20% and recharging them to at least 80%, and some of these batteries have driven their RAV4 EV’s well in excess of 100,000 without battery refurbishment.
    ==================================

    1. You can’t always get what you want. What is 2 minutes of charging in one day? One week? One month?
    It’s a car that runs on eectricity. It is not an all-electric car.
    I hope people aren’t looking out for an all-electric EV!

    2. Which car company in the world has ever let the customers set performance parameters?
    Toyota? Honda?
    Why should it be any different with GM?
    They warranty the battery (at your insistence–and wisely, since you couldn’t afford the battery at cost anyways), they get to set the parameters.

    I am sure they’ll extend the range down the road when the battery technology improves.

    3. These are not NiMH batteries, they are Li-Ion and brand new at that.
    So what RAV-4 people allegedly do with their batteries is irrelevant really.


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    Aug 26th, 2007 (5:03 pm)

    # Hoang Says:
    August 24th, 2007 at 6:30 pm Quote

    To the 40+ miles and recharge problem, I think they can add GPS so that the car knows when you are near your home or wherever you can plug it in( custom settings ), the generator will shut off and let the battery deplete to 50% or whatever level. Nowadays, $300 can buy you a good GPS. And I don’t think adding about $300 to the car’s price tag is that bad.

    My 2 cents
    ==========================================

    I am sure someone will be able to hack this one. Of course, “near home” is relative.

    For sure, your warranty will be shot (as well).


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    Aug 26th, 2007 (5:05 pm)

    # kent beuchert Says:
    August 24th, 2007 at 6:57 pm Quote

    I suspect that GM will have a “kill” switch to turn off the IC engine so that you can motor into the garage with the battery as close to the 50% mark as possible, so that you can fill the battery off the grid as much as possible.
    Just heard that the plug-in Dodge that they are using to test the “plug-in concept” (apparently the Dodge folks can’t grasp the notion) has a 220 voly input. Let’s all urge GM to do the same and allow both 110 and 220. Remember, with a 220V/50AMP circuit, you can stream 8 kilowatt hours worth of juice for a complete fill up in only 44 minutes. That means plug in after work and ready to go again after a short dinner. Could easily refill 3 times a day if schedule permits and get 120 miles of all-electric cheap travel. A 12,000 mile per year car averages 33 miles per day, a 15,000 mile per year car averages 41 miles per day.
    =========================================

    My math may be off, but 44 minutes is not a “short dinner”.

    At 110 volts, 88 minutes would be just fine. I get your point though.


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    Aug 26th, 2007 (5:11 pm)

    # stormc Says:
    August 24th, 2007 at 7:21 pm Quote

    I have an electric car. You guys should get off the 40 mile kick. The range on battery power depends on how you drive it. Jack rabit starts and high speeds will reduce it drasticly. On the other hand, driving conservatively will increase it.

    FWIW, I volunteer to test the beta model!
    =========================================

    That’s right. Everybody wants everything for free.

    You will have to change some of your habits of you are to get the most out of your vehicle.
    I cannot wait to hear complaints about variation in mileage from the clueless:

    Lead Foot 1: “I am very angry at GM! I will never buy another again! Last night I only got 20 miles out of my battery! It’s defective! The dealer says it’s my fault!”


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    Aug 26th, 2007 (5:18 pm)

    # Paul Says:
    August 24th, 2007 at 10:05 pm Quote

    Stormc is right.

    40 miles is not cast in stone. If you drive leisurely, Volt may get 50 miles on batteries. Or maybe 30 if you have a lead foot.

    But one neat thing (not discussed yet AFAIK) is that GM can EASILY control the max power that can go to the wheels. So just in case someone from GM is reading this…

    Maybe GM could let the Volt run in one of two modes. The mode already described (with the generator operating between 50% and 80% SOC), could be called the “performance” mode. It uses all the power available, for when you want to impress your friends, or at least prove that a Volt is not just an awesome looking golf-cart.

    Also introduce an “economy” mode. In this mode, the generator could run between 20% and 50% SOC. Also, the amount of power available to drive the wheels would be reduced, say by 50% of max. The reduced power would both prevent lead-foot driving (more economy) and prevent Volt from being driven so as to completely deplete the batteries.

    It’s a simple enough solution (one toggle button) that even Grandma can use it. And it also lets you easily utilize (if you choose to) about twice as much grid electricity. Obviously, my percentages above were made up as an example. GM would need to conduct some tests to determine what values make sense. Who know … maybe even three modes: “Performance”, “Standard”, and “Economy”. I think Grandma could handle a button with three settings also.

    So what would this do for electric range?

    In economy mode (with reduced power usage as described above), the range from 50% of the battery capacity will probably be 50 miles, not just 40. And in economy mode, you can use 80% battery capacity before the charger kicks in. That would be 80 miles on pure electricity folks! I think it’s possible.
    ============================================

    Now this is an idea I like.
    I like it a lot.

    That is a way to give people meaningful control without making a car for the requirements of geeks.

    Maybe they could add speed limiters, retard acceleration etc.


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    Aug 26th, 2007 (5:28 pm)

    # Steve F Says:
    August 25th, 2007 at 9:01 am Quote

    Another option to manage battery recharge and believe is better than a manual kill button. By default Volt will start recharge at 50% and recharge to 80%. Have another option to set the range of the recharge cycle. Allow change recharge to start at 50% but stop at 60% or 70%. The result is if drivers just need a smaller recharge to get to home at a max of 60% then they have control over recharge and can max home plug-in charge. The good point is that it still handles drivers that mis-calculate the range or have different driving styles. If for example, it recharges to 60% but then they drive back down to 50%, then ICE would once again recharge to only 60% and then finally get home to plug-in. Then maybe when they turn it off for the night it reset to default 50% to 80% recharge. I think this would be better than some manual kill button that each driver would have to figure out and give impression on system complexity.
    ========================================

    The engine provides electricity to charge the battery to run the car.
    However far the re-charge has gone when you pull into the garage and shut off the car, is how far it will re-charge.

    Your comments show that you think this is an immediate-recharge battery. No such thing exists (not in this sector for sure).

    It will only get to 80% if you’re out and about long enough for it to get there. If you get home by the time it gets to 50%, then it will stay there (no switch needed).


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    Aug 26th, 2007 (5:40 pm)

    # CW Says:
    August 25th, 2007 at 12:07 pm Quote

    My normal drive is 43 miles pr day total. If the charge starts 3 miles before I get home and I can’t stop it some how It will defeat the purpose of the car. I might as well buy a Yaris. I love the concept of the Volt and am ready to buy but If I can’t take advantage of the home charge it will be a deal killer for me.
    ======================================

    You could not be serious!

    Are you kidding us here or what?

    3 miles at 50 miles per gallon is 0.06 gallons of gas.

    The Yaris would be driving 43 miles at 37 miles per gallon (average of 34 city/40 highway). That would be 1.2 gallons of gas–approximately 20 times more gas per trip with the Yaris.

    Did you do any of the math at all?


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    Aug 26th, 2007 (5:43 pm)

    # Dan Says:
    August 25th, 2007 at 3:15 pm Quote

    Hi Matt 986,

    I think you missed the point. Let’s say that the car is fully charged. I drive 45 miles. When i get home the car will be charged near 80%. For the last 5 miles the car will try and charge itself using gasoline.

    Same thing the next day, and the day after. In this scenario, I only get to charge the car from my home electric for about 40% of the milage. The other 60% of the milage is being charged by the gasoline engine.

    That is more significant than just burning gas for 2 minutes.
    ========================================

    Where did you get the idea that the car will reach 80% charge in 5 miles?


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    Aug 26th, 2007 (5:53 pm)

    # pstoller78 Says:
    August 25th, 2007 at 5:10 pm Quote

    Shouldn’t it be possible to run the generator at a level that would maintain the current level of charging. Basically only provide enough power to prevent the battery from discharging below 50% but not charge it any more than that. I would think it would be as simple as running the generator at lower RPMs.

    Perhaps the ICE could use an HCCI mode at this charging state as the ICE wouldn’t need to run under full load and could benefit from HCCI.
    ==========================================

    HCCI is new. I am sure any future Volt will get HCCI simply because HCCI is ideal for constant RPMs.

    I still don’t know why people are nitpicking. What is 3 miles a day of the engine running? It most certainly will not charge to 80% from 50% in 1 minute. Has anyone here ever used power tools before?

    Even if your commute is a constant 43 miles a day, you’ll still be better off with the Volt. You live too far from work anyways (way more than most Americans).
    At that point of pickiness, you’d be better off taking public transport (which is better for the environment than even the Volt).


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    Aug 26th, 2007 (6:11 pm)

    # Pete Says:
    August 25th, 2007 at 11:36 pm Quote

    Dave,

    Based on the reliability of electric motors and the low temperature performance of Li-ion batteries, your concern about being stranded after parking in cold weather is not warranted. However, there would be a concern about being stranded due to design flaws which can happen with any new product. This is the reason that some people will wait for Volt II.

    The 50% engineering margin is far too much and, for a 40-mile all-electric range (AER), it would require 16 kWh of battery capacity or 60% more than the 10 kWh needed with a 20% margin. A 20% margin is quite sufficient for over 15 years and 250,000 miles of battery life based on A123’s claim of 7,000 cycles at 80% depth of discharge (DOD) – from 100% to 20% SOC. The cost of a 60% increase in expensive battery capacity would certainly be passed on to the consumer and would severely impede the Volt’s market acceptance much to the delight of Toyota, the oil companies and luddites in GM.
    ==========================================

    GM has been making cars for maybe close to 100 years. What on earth are you talking about “being stranded because of design flaws”?

    GM is a brilliant car company with some of the most brilliant engineers in the business (as anyone with a proper knowledge of the car industry knows). Your views about GM were always misguided and are almost certainly outdated.


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    Aug 26th, 2007 (10:24 pm)

    Forget all this nit-picking.. bring on the Volt, I\’ll buy it… Then bring on Volt-II, I\’ll buy that one also.


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    Aug 26th, 2007 (11:01 pm)

    You could not be serious!

    Are you kidding us here or what?

    3 miles at 50 miles per gallon is 0.06 gallons of gas.

    The Yaris would be driving 43 miles at 37 miles per gallon (average of 34 city/40 highway). That would be 1.2 gallons of gas–approximately 20 times more gas per trip with the Yaris.

    Did you do any of the math at all?

    You missed my point and yes I can do the math. In my Solstice the fan continues to run after I shut the engine off. If the Volt continues to recharge the battery after the car is shut off it would be a problem. But I don’t think that will happen. And no I’m not going to buy a Yaris. :) CW


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    Aug 27th, 2007 (9:49 am)

    I have been reading everyone’s comments over the past 2 days. It would be nice for GM to build the Volt with all these things in mind but it’s probably not possible. They are building the car to specification to comply with approximately 75-80% of American driving.I personally would like a longer range, but it’s not in the equation. One comment I saw was wanting a kill switch so they could get home without using gas. Look at it from this perspective. If you drove home say the last 10 miles on gas and the battery recharged to a certain point, you not only got approx 50 miles to the gallon but also the mileage the electricity produced when it was rechaging. Better than 50 mpg counting both. There are a lot of good ideas here and maybe GM will incorporate a few. Let’s wait and see. Either way I think GM has a winner. Oh Lyle by the way keep up the good work.


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    Aug 27th, 2007 (6:05 pm)

    Here is how you beat the lack of a kill switch with no hacking required. Just don’t put any gas in it, period. Do you think they are going to make the car stall at 50% battery capacity??


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    CM

     

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    Aug 27th, 2007 (11:16 pm)

    “Here is how you beat the lack of a kill switch with no hacking required. Just don’t put any gas in it, period.”
    =========================================
    And have a warning chime drive me crazy? No thanks. And why have an engine and tank if you don’t plan to use it? There will be battery only cars available, even GM might decide to offer one!
    =========================================
    “My math may be off, but 44 minutes is not a ‘short dinner’. At 110 volts, 88 minutes would be just fine. I get your point though.”
    =========================================
    Your math is off. The power is Volts X Amps, and a standard 110 volt outlet is limited to 15 amps. That means 1,650 watts, or about 1.6 Kw. That would take nearly 5 hours to transmit 8 Kwh, but the charger isn’t 100% efficient, so figure 6 or 7 hours, maybe a bit longer. GM really should support higher power charging, 220 volt 50 amps would be 11 Kw, making a 1 hour charge a real possibility.


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    Aug 27th, 2007 (11:18 pm)

    Questions says:
    GM has been making cars for maybe close to 100 years. What on earth are you talking about “being stranded because of design flaws”?
    ——————————————
    Lemons, which I must admit could be due to a manufacturing flaws as well as a design flaws. Every car company has them and why should GM be different.

    Questions says:
    GM is a brilliant car company with some of the most brilliant engineers in the business (as anyone with a proper knowledge of the car industry knows). Your views about GM were always misguided and are almost certainly outdated.

    “brilliant car company…brilliant engineers” Give me a break. What are you a GM apologist? As far as the Volt goes, GM has no need for an apologist. Your comments are a severe over-reaction to my allusion to luddites in GM. Are you suggesting that GM does not have people who resist change of any sort?


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    Aug 28th, 2007 (12:57 pm)

    Wait a minute here. Where did the correlation of 50% battery draw = 40 miles of driving. That seems a hasty generalization. I know I read 40 miles on a charge (100% to 0%?), and I read a 50% draw down before the ICE kicks in, but no where did I read that you could go 40 miles using only 50% draw down on the battery…I think we are jumping ahead of ourselves in this category – unless someone can show me where I might find this information…


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    Aug 28th, 2007 (1:10 pm)

    [quote comment="5394"]Wait a minute here. Where did the correlation of 50% battery draw = 40 miles of driving. That seems a hasty generalization. I know I read 40 miles on a charge (100% to 0%?), and I read a 50% draw down before the ICE kicks in, but no where did I read that you could go 40 miles using only 50% draw down on the battery…I think we are jumping ahead of ourselves in this category – unless someone can show me where I might find this information…[/quote]
    Dave
    GM has officially told us that 50% of the batteries’ capacity (8 kWh) will give a 40 mile (avg) driving range.


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    Aug 28th, 2007 (1:57 pm)

    can you offically put a name with this quote? The physics suggested by this is that the Volt can go 40 miles using 8000 watts (40 mile/hour basis). That doesn’t seem likely to me. I’ll do some nerd figuring here until I can wrap my brain around this.


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    Aug 28th, 2007 (2:55 pm)

    Sure Dave
    It comes from Rob Peterson, GM’s E-Flex spokesperson.
    We are talking about a battery that is capable of 200 Wh/mile.


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    Aug 28th, 2007 (10:39 pm)

    Dave,
    To get a quick ballpark figure for miles per kWh use the specifications for the Tesla Roadster – 200+ miles of range from about 55 kWh of energy from 6,831, 8.0 Wh 18650 cells. This would equal 3.6+ miles per kWh, probably at 60 mph.

    Better yet, Calcars claims 5 miles per kWh from its Prius conversions. This seems reasonable for 40 mph, if the Tesla figures are for 60 mph.


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    Aug 29th, 2007 (3:14 pm)

    I think there is reason to think that this could work out. I thought that the rolling resistance (mass, wind, friction) for an average sedan-type vehicle requires 20 horsepower to maintain highway speed. 8 kWh is only 10.78 horsepower hours. If the rolling resistance can be maintained in the 10 hp range, I think this could have a shot at the 40 mile range. If it is closer to the 20 hp, it should be proportionately less. Through an associate, they claim to have read that the rolling resistance for the Honda Accord was in the ball park of 10 hp.


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    Aug 29th, 2007 (7:37 pm)

    If these guys build this, I’m gonna buy one.

    By the way, I work for Chrysler.


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    Mike756

     

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    Aug 30th, 2007 (6:59 am)

    The DOE’s AVTA testing of PHEV converted Priuses shows that they use about 0.2kWH/mile, about the same as the Volt.

    http://avt.inl.gov/phev.shtml


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    Sep 14th, 2007 (11:43 am)

    All the hub-bub about having to go 45 miles and not wanting the ICE come on – I would hope GM would put a \


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    Sep 14th, 2007 (11:46 am)

    Sorry – my last post got cut off…..

    What’s all the hub-bub about having to go 45 miles and not wanting the ICE come on – I would hope GM would put a “snooze” feature on this wonderful concept that would over ride the ICE in 5% or so battery life increments. If you “snooze” too many times – the computer / ICE take over. Hey – if an alarm clock can do it…..


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    Sep 19th, 2007 (12:47 pm)

    Also – what about mounting some solar cells in the roof area so the car can charge while sitting in the office parking lot all day?


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    Sep 19th, 2007 (2:06 pm)

    “Also – what about mounting some solar cells in the roof area so the car can charge while sitting in the office parking lot all day?”

    Solar built into cars, even when charging batteries all day, only works when your car is nothing but a flimsy quadricycle.


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    Jan 15th, 2008 (7:00 pm)

    progressive alarm clock…

    This modern alarm clock wakes you up each morning. On the other…


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    Eric

     

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    Jan 28th, 2008 (4:20 am)

    Eric…

    This is real good info. Thanks for sharing….


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    Apr 24th, 2008 (4:49 pm)

    I would never buy a chevy, ever. Except this. I buy a new car every 2 years, always german or japanese, but if Chevy can produce a vehicle like this I’ll buy it. This is the big chance for US automakers to catch up and start to turn profits again, by leaving behind outdated combustion technologies and jumping into new realms of innovation. Now if only they’d done this 10 years earlier we might have had a chance to save the planet. (yes I’m aware gm killed the electric car once before…)


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    Jan 5th, 2009 (4:54 pm)

    Nick D Says: @41

    “People are concerned that if they hit the 50% threshold the engine will turn on and completely charge the battery using gasoline (in other posts the time to top off the battery was estimated to be less than 6 minutes.) Then coming home to your garage with less gas and a fully charged battery, when the most desirable option would be to have the gas engine charge the battery only partially allowing the user to charge up the battery using electricity, not gasoline, or in my case ethanol.”

    ***************************************************************************************

    The option of reaching home with the battery discharged at it’s maximum,, I believe, will still be available as mention on a prior post. To do this, the driver will have to interact with the computer letting it know you plan to reach home with 80% of the battery discharged. Of course, this will require a GPS working with the car’s computer..


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    BOB

     

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    Feb 20th, 2009 (9:02 am)

    jahklsdjjjjsssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssskjjjjjjjjjjjjsdhfkgjhakljdhfiunkjgjahnjhgnjajhcbn jhgsfkajnbkjacghksjghkdbjhc yaaa chevy rules


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    Feb 20th, 2009 (9:03 am)

    its woundeful=)


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    Aug 17th, 2009 (9:20 am)

    To everyone concerned with mimimizing gas engine ‘turn-on’ time, it’s not such a bargain. Assuming the rough figure of 8kWhr recharge capacity, it’s about a dollar worth of electricity, so you aren’t saving that much–the gas engine would probably use 2-3 $ of gas to cover the same distance. Energy is fungible; you gotta pay one way or the other.

    Sometimes I think that it would be a good idea to replace dollar with Joule as currency—it would make many things related to energy conservation more transparent. Right now, I have a great way of explaining this to my kids: one Watt of power costs one dollar per year. Joule currency would make it very easy to explain.