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Monday, January 08, 2007

GM's New Electric Vehicle

The automaker tries again, announcing an electric-drive system that can be paired with gasoline generators or fuel cells.

By Kevin Bullis
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Schematics of GM's Chevrolet Volt concept car, which was unveiled today at the North American International Auto Show, in Detroit. The battery pack along the center of the vehicle stores enough energy to give the car an all-electric range of 40 miles. Once this limit is reached, a gasoline engine kicks on to generate electricity, recharging the battery and allowing a total range of 640 miles.
Credit: General Motors

Recently, General Motors (GM) has faced criticism for shutting down production of its EV-1 electric vehicle. Yesterday at the North American International Auto Show, in Detroit, it unveiled the EV-1's successor, an electric-motor-driven concept car called the Chevrolet Volt. It's the first example of a new "E-Flex" vehicle platform that the company is moving toward production.

The concept car runs off electricity from the grid, stored on board in a battery, for the first 40 miles of a drive. For longer trips, a small gasoline-powered generator kicks on to recharge the battery pack, allowing a total range of 640 miles. In between trips, the battery can be recharged in six and a half hours at an ordinary wall outlet. For longer trips, the generator can provide power at the equivalent of 50 miles per gallon.

GM representatives say their reason for including the gasoline generator is to overcome one of the biggest limitations of the earlier electric vehicle: the short range. The original EV-1 had a range of only about 90 miles, and it required an eight-hour recharge at a dedicated 220-volt electrical outlet. The Volt uses lithium-ion batteries that take up one-third of the space of the EV-1's original lead-acid battery pack, while providing the same total energy storage.

 

The new vehicle is an example of what's known as a series hybrid, another in a growing type of hybrid-vehicle variant. In conventional hybrid vehicles, such as the Toyota Prius, the car can be propelled by a gasoline engine, a battery-powered motor, or both. In a series hybrid, the gasoline engine has no direct contact with the wheels. It serves only to recharge the batteries. One of the major advantages of such a system is that any source of electricity can be used to charge the battery. This includes electricity from a wall outlet, but also electricity generated on board by a gasoline-, ethanol-, or diesel-powered generator. Because these generators can run at a constant speed, they are more efficient than an engine that has to ramp up and down to meet demand.

GM is developing a combination electric motor, alternator-like generator, and battery pack that can be used with various power sources. For example, an engine that runs on diesel might be preferred in Europe. An engine that runs on ethanol might be favored in Brazil. In a hydrogen fuel-cell version, the battery pack would be smaller and primarily used to provide a boost of power and to recapture energy lost from braking.

Last year at the Los Angeles Auto Show, GM announced work on a plug-in hybrid. (See "GM's Plug-in Hybrid.") As with the Volt, the plug-in hybrid can recharge from a wall socket. But the electric motor will not be the sole source of propulsion: an internal combustion engine could provide bursts of acceleration or power for climbing hills. The plug-in hybrid would not switch among the different sources of energy as easily as the series-hybrid system could.

For both the plug-in and series hybrids, GM says the timeline for commercializing the vehicles will depend on the development of the battery systems. But such systems may not be far off. GM representatives say that they have already seen lithium-ion cells that have the performance required for both plug-in and series-hybrid applications. What remains to be done is to combine these cells into large, complex battery packs and make sure they work well together in an actual vehicle. Last week, GM announced that it has a contract with two sets of companies for building lithium-ion-based battery packs and control systems for plug-in hybrids.

Comments

  • No excuses for not building now.
    asdar on 01/08/2007 at 8:11 AM
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    The batteries are there now for an all electric 40 mile range.

    Even if the car costs too much to be mainstream just getting something out there would go a long way toward repairing the EV1 damage.

    I hope they lower the windows. I hate driving cars with a slit window.
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    • Re: No excuses for not building now.
      donfleming on 01/08/2007 at 10:38 AM
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      Plus, why are we not doing this with a clean diesel generator, yielding even more equivalent mpg?  Expense?
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    • Re: No excuses for not building now.
      lambdafunds on 01/08/2007 at 11:13 AM
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      The EV-1 failed.  GM sold it at a large loss.  Not enough people wanted to buy at full price.  The car was withdrawn, as no manufacturer would want to offer 20 years of dealer support for a specialized vehicle.

      The E-flex vehicle can't be built now, as the batteries do not yet exist!  At least GM is trying to think of the future.
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      • Re: No excuses for not building now.
        bylsma_2000 on 01/08/2007 at 1:18 PM
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        Batteries do exists for this application.  www.teslamotors.com has a car going into production with these exact batteries and has no recharge motor and will go 300 miles to a charge.  www.altairnano.com has SUV they built with similar batteries only they do one better they can recharge in 10 minutes.  I think GM would be better served investing into that type of technology but at least they are learning from their mistakes.  Way to go GM.  Now build them before Toyota and Honda do!
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        • Re: Not true, it's still not ready for mass-production
          colinnwn on 01/09/2007 at 11:10 PM
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          This is simply not true.  I am a little dubious the Li-ion batteries aren't close to being usable.  But they take too many scarce resources and are too polluting to mass produce. 

          However, Altairnano's technology looks to be no where close to ready for mass production.  They have basically created a proof of concept. 

          And the WORST information is that you could recharge their battery in 10 minutes.  Sure the battery might be able to take it, but the power grid can NOT.  Recharging it would blow your residential electrical service.  You would need electrical service equal to a mid-sized company.
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        • Re: No excuses for not building now.
          DrWelly on 01/10/2007 at 1:04 PM
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          Tesla is a full battery-powered electric vehicle, which is a "little" different from the GM's EV (or series hybrid) concept described here.  This version is a more robust and adaptable to the ever-changing energy storage and propulsion technology.

          On another aspect, many high-power battery chemistries can be recharged in 10 minutes, not just Altairnano as claimed.  The key factor is whether it can be recharge efficiently and safely.  Also, if you read between the lines, the 10-minute recharge only implies to 80-90% capacity.  No matter how it is sliced and diced, only mid-60 or 70% of the full Ah capacity can be used in an EV or HEV or PHEV.  Besides, charging a 300V / 50Ah battery pack in 10 minutes or less will require a 100+kW system (or sub-station) that can easily supply for a small city block.  So forget about the fast-charging aspect if this "New EV" is going to fly.  The fast-charge capability in battery is useful however to ensure effective regen.

          Much like the fuel cell vehicle architect, the concept of using series hybrid is to provide a mean of low-rate battery charging and simply the drivetrain to electric only.  But, the big question is if the battery can be recharged fast enough or the generator is big enough, especially, with mostly short trips to maintain a useable vehicle ... because - unlike today's parallel hybrids - there is no "back-up" gasoline engine to drive home even with a full tank of gas.
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      • Re: No excuses for not building now.
        HaPPI on 01/08/2007 at 1:24 PM
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        Of course the batteries exist.  They are in every hybrid on the street today.  Plug in is just larger.

        A correction to the article: Plug-in hybrid can be either parallel or series.  The issue is whether the system allows the electric motor to move the vehicle without the other power source running constantly.

        I'm glad to see GM getting it.  Too bad they took such a thrashing to learn, though.
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    • Re: No excuses for not building now.
      theBike45 on 01/09/2007 at 9:43 AM
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        The idea that an automaker could start building what is nothing but a concept car tomorrow shows extreme ignorance of the industry. The Pontiac Solstice  was created in record time by taking a calculated risk and not building interim test vehicles. It took more than 2 years to bring that car to market, a car that used many off te shelf parts. Now this bright feloow is claiming that GM can start building this al new, unproven technology tomorrow. Unbelievable the lack of kowledge around here about the automotive world - but it doesn't sem to prevent some mensa types from oholding strong opinions. And oh, by the way, Toyota and Hoda both killed their electric cars,
      but a lying Chris Paine never bothered to mention that in the film - one reason is that he extroted promises from Toyota in return for not including them in thefilm. And the EV1 was a piece of useless crap that never should have been brought to market - $45,000 for a car that can't get you out of the county, and needs a new $20,000+ battery pack every 5 years. Only those gullible fools that believe Paine's fictitious documentary
      think the EV1 was anthting other than the automotive flop of the century. It was no advance over the Detroit Eelectric car, produce before WW1 in 1907. There's no excuse for people being so uninformed.
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      • Re: No excuses for not building now.
        bylsma_2000 on 01/15/2007 at 1:55 PM
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        Hmmm. I think you need to watch the movie again, but I think it would get in the way of buying stock in oil companies.  They did say that Toyota and Honda were crushing them as well.  There is like 10 to 15 minutes on that subject, let alone a part of the trailer.  As far as their being enough power to recharge in 10 minutes.  This would only be necessary at an old crappy gas station, which is a small business, not needed at your home.  The technology in the nanosafe battery allows this to be much safer.  It is not as out of reach as say a Hydrogen fueling station (which I think is more mythological than any other idea).  As far as weather or not producing that sort of battery is possible in a mass market, it is totally possible.  They only need money and time; we have a lot of that in this county.  Take all the wasted money into hydrogen research that the Bushies have blown on and push it to the battery people.  The battery powered drive train wins hands down with how many resources it would take to produce it.  I work in the plastics industry; I see a ton of potential in driving that cost down.  I want the big three to do well.  I want them to create jobs and new energy is the only way...  I repeat the only way that we will ever be a viable entity in the consumer auto industry is with new energy.
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      • Re: No excuses for not building now.
        bylsma_2000 on 01/15/2007 at 2:21 PM
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        Oh yeah I forgot to mention your ignorance about the Pontiac Solstice.  They didn't need to build a test car because they didn't develop the car.  It took two years to get it to market because they have people who analyze the market and produce and sell the car when they think they can sell the most cars.  The car was originally designed by Lotus for Vauxhall.  It was dropped and Lotus had it in their arsenal so GM picked it up and slapped their badge on it.  Some cars are brought to market in 8 to 9 months; this is done without any prototype tooling.  Sure they build prototype cars but they do it with custom made parts.  Thus allowing developers to build production part data as they are testing the proto car.  The funny thing is that I don’t believe anyone thinks this car could be out next year.  I didn’t say that, I don’t believe anyone else said that.  How could you argue about only positive things, that I don’t understand.  That is the true sign of ignorance, being negative in a positive situation.
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      • Re: No excuses for not building now.
        bigoilman on 10/25/2007 at 12:36 PM
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        Corrections: the EV-1 was NOT a "flop" nor was it under "sold". The Ev-1 was never sold, they were leased. GM made only so many and stopped after realizing they would not be profitable, i.e. too efficient. State of CA even started setting up charging stations. It was mothballed by GM intentionally. They recalled all EV-1 from leasees w/o option to buy. See documentary "Who Killed the Electric Car?"
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  • multi-source
    asdar on 01/08/2007 at 11:00 AM
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    I can't fault them for going gasoline in the U.S.

    They're a business and they have to sell what people are buying.

    I think they mentioned that they envision having a diesel for Europe and Ethanol for Brazil, fitting the generator type to the most plentiful fuel supply.
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  • Batteries are key--and not so far away
    felix kramer on 01/08/2007 at 12:48 PM
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    Excellent report. Kevin Bullis confirms that GM has already seen batteries at the cell level that can do the job. For CalCars' analysis of all this, see CalCars' 16 Points about GM's PHEVs at http://www.calcars.org/gm-phevs-faq.html.
    -- Felix Kramer, Founder, The California Cars Initiative
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  • Don't be distracted by 1 concept car
    mleonard on 01/08/2007 at 3:04 PM
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    It's great to see a major automaker finally moving forward on what small companies have been proving possible for several years (see Energy CS, CalCars and HyMotion). But while the announcement is exciting, GM still isn't giving any solid timeline on WHEN we can see these cars on the road or HOW MANY cars are actually going to be produced - at best they say 3-4 years if the battery technology is available. There is a demand for plug-in hybrids NOW - there are hundreds of cities, counties, utility districts and fleets already placing "soft orders" for such vehicles. Such early-adopters of these vehicles would provide test markets for GM to refine the technology and build public confidence and interest in these cars.

    I have to admit I'm a little concerned that they will use the announcement of these concept cars more to clean up their image than clean up their product line. There is a lot GM can do between now and when we may see these concept vehicles actually on the road.

    We all know increasing fuel efficiency is the direction automakers need to head – so let’s get past the hype of a handful of concept vehicles and look at what they are doing with the rest of their fleet. Overall average fuel economy from the Big 6 is worse today that it was 10 years ago and GM is still heavily dependent on its gas guzzling truck lines. In addition to that they are still fighting tooth-and-nail against increasing fuel economy regulations, suing states that try to limit greenhouse gas emissions, and in December argued before the Supreme Court that carbon from tailpipe emissions was not even a pollutant. GM is still planning to expand their Hummer line to become 25% of their overall sales. Consumers still have limited options to find fuel-efficient cars that are affordable, well-built, and fun to drive. There are plenty of things automakers can do today to increase fuel economy – and I'm tired of being shown distracting concept cars that we won't see for 3-4 years if ever.

    I've been working with the Freedom From Oil Campaign to make automakers honestly prioritize fuel economy and move beyond oil – check out what we do at http://www.FreedomFromOil.org
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  • Battery Quantity?
    Colin on 01/08/2007 at 8:39 PM
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    Sure, the battery technology exists, but are the batteries produced in sufficient quantity at a reasonable price that makes it possible to sell the automobile to Americans?  I'm betting GM won't retool a factory until they know they can sell a LARGE number of the new automobiles. 

    Of course, no matter how long they wait, a better battery technology will come along as soon as the cars hit the showroom floor....
    Colin
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  • Watts Question
    mkogrady on 01/09/2007 at 12:40 PM
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    Anybody know how many watts of power it will take to move the vehicle 10 miles in normal traffic?
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    • Re: Watts Question
      colinnwn on 01/09/2007 at 11:02 PM
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      Watts is instant power, I think you really want to define it in energy terms or power over time.  You need watt-hours or 1 watt used for 1 hour.  The instant energy use would fluctuate wildly from accelerating and coasting and based on the weight, rolling, and wind resistance of the vehicle. 

      For an estimate, lets say the power requirement in city traffic traveling 30 miles an hour averages 20 horsepower.  20 * 746 = 14,920 watts divided by  the 20 minutes of travel time is 4,973 watt-hours.
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  • Plug in cars
    sbabinchak on 01/09/2007 at 4:45 PM
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    I think this may be the holy grail for the next decade while GM works on hydrogen. In order to be sucessful these things must be present: It must be affordable, it must live up to its expectations, it must not explode or cause some other unwanted unknow to occur in an accident or while driving it, and it must be decent looking. If it is sold to hard-core tree huggers as a "stepping stone" towards hydrogen I think they will go along with it since plug ins still create pollution from fossil fuel buring power plants. Go GM GO!
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    • Re: Plug in cars
      asdar on 01/10/2007 at 10:07 AM
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      Sbabinchak, I couldn't disagree more with your post, at least about the Hydrogen, no disrespect intended.

      Hydrogen is a mirage that's taking money foolishly. The real goal is full electric and this goes about 78% of the way if you trust statistics.

      I think the battery technology is already there. A123's, Saphions, Altairnano and even Firefly's lead acid battery would supply a 40 mile range, with decent cycle life. I wish they'd build it with an open envelope for batteries and if the batteries aren't quite what they want as a final goal, what's the big deal. At least they'd be one step up on the competition.
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  • There is hope
    gabrielg01 on 01/09/2007 at 11:04 PM
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    I used to say that 'GM' stands for the 'Great Moron'...hopefully, these new developments will prove me wrong.

    I'd love to buy an electric car.
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  • Bring the Volt to Showrooms
    silas10961 on 01/10/2007 at 8:08 AM
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    I would purchase this vehicle today. Come all the way through with this one GM. Deliver it to the showroom floor, and it's sold.
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  • We shoud act now to change transportation and not wait for batteries to solve the problem
    Tom on 01/10/2007 at 10:15 AM
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    Existing and future batteries will never have the energy density of a gazoline tank (the quantity energy per unit of volume). Electric vehicles will therefore never be capable of performing the same functions as a conventional car (long range).

    I believe that there is a great potentiel for hybrid/electric vehicles, but we need to rethink the car and what we expect from it (weight, seating capacity, auxiliaries like A/C, etc.).

    Promising breakthroughs in battery development encourages to wait.

    http://funboby.blogspot.com/
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  • Series vs Parallel efficiency in gas mode questions
    dara on 01/10/2007 at 9:23 PM
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    I understand the advantages of series hybrids for a plug in design.  You can run pure electric at full power for acceleration and at highway speeds (until your battery pack runs low).  If I were to turn my Prius into plug in (and I won't), I'm limited in what percentage of electric power I can use in that first 40 miles since the electric motor is only 30 kW.

    However, I thought there was a significant penalty to be paid in gas mode if forced to go through a generator, electronics, and motor (and some battery buffering) when compared to driving the wheels directly (albeit with transmission losses).  Is there anything interesting about GM's new design that gets them a 50 MPG gas mode?  Are the electronics or motors more efficient?  Is the engine more efficient?

    Another issue with series hybrids can be their mass.  What size generator and gas engine did they go with?  What size electric motor?  I presume they downsize the gas motor and generator somewhat to use the advantage of battery buffering, and evidently it is enough to keep the mass of this car low enough to still get 50 MPG. 

    In http://www.calcars.org/gm-phevs-faq.html, they say:

    Engineers see series systems as simpler, but say parallel PHEVs create the most optimal combination of weight and power in components, to get the best MPG equivalent."

    So it isn't a trivial thing they've done here.  Where to find more details?

    Dara Parsavand
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    • Re: Series vs Parallel efficiency in gas mode questions
      asdar on 01/12/2007 at 8:47 AM
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      I'm surprised as well that they reached the point of 50 mpg with a generator.

      We knew we'd get some efficiency back because running the ICE at a constant RPM is more efficient, but I don't know how they get the rest to come out so well.

      This has to be some kind of a coup for GM if it's all true. Honda has been the king of generators so I'd expect them to be the first to pull this off.
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  • Why does Detroit drag its feet for so long?
    Ecowriter on 01/22/2007 at 3:31 AM
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    I mean, every year they drag it out, people are forced to choose among alternatives that are often not very satisfactory.  This strikes me as a good baby step forward, and if they'd taken it ten years ago, they could have been heroes.  Instead, they messed around whining for most of that time about how the technology isn't mature.  But Honda and Toyota are already close on a lot of this stuff, and we'll probably end up having the Japanese and Chinese companies eat our lunches yet again.

    Sigh.  I wish Detroit would finally understand that lots of people want good fuel economy and also want to feel they aren't screwing up their kids' lives by driving a polluting vehicle.

    Hello, Detroit, it's the clue phone, and it's for YOU...
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    • Re: Why does Detroit drag its feet for so long?
      Boyceg on 01/22/2007 at 11:32 PM
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      Remember the diesel Olds?  I did 17 years with those things.  I got too old and tired to pull an engine out every 12-18 months.  And, there are a lot of 95HP cars that get 32 miles per gallon.  All of them outrun the diesel Olds, easily.  GM knew the engine was a dog, but we would buy anything with a diesel engine in those days.  GM really never did finish the design.
        So, Detroit does turn out new stuff from time to time, but they do too many of them poorly and then give up and don't see them through.  Honda has something like 21 different concepts active.  But, Honda is run by engineers who use to design and manufacture cars.  The problem is that Honda is run by engineers who use to design and manufacture  cars.  They do seem to know that if they put all their ideas into one car, they can be assured it will fail, but they may learn a lot.  I believe that is called "doing development work on the customer's back."
        Right now, I understand that Ford spends more on R&D than any other company on the planet.
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  • Plug your car into the grid?Might as well have a coal powered car?50-60% of electricity in the us is coal.
    curtismartz on 03/03/2007 at 11:40 PM
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    Hybrids are just forestalling the inevitable and ideal, abandonment of hydrocarbon fuels.
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  • battery charger
    rock47 on 03/28/2007 at 12:44 AM
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    all for all electric cars...any technology out there using the natural wind power to recharge the battery while the vehicle is in motion?? Just a WILD idea?
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  • plug in - will the market accept it
    penman on 04/19/2007 at 12:48 PM
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    GM's NEV is a good idea, but I question if a vehicle they have to remember to plug in every time they go home could gain mass acceptance.  Some type of technology needs to be built in, so this becomes automatic. 
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  • EV1, Dick Cheney INC.
    db_crm on 05/18/2007 at 8:29 PM