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GM to pick Volt battery maker in next few months

DETROIT (Reuters) - General Motors Corp (GM.N: Quote, Profile, Research, Stock Buzz) will announce a battery supplier for its all-electric Chevy Volt by the end of the summer, an executive said on Friday.

"My guess is that we'll have an announcement before the end of the summer," Tony Posawatz, the senior engineering executive heading up GM's Volt development program, told Reuters.
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Separately, Posawatz said GM had been approached by utilities interested in using recycled Volt batteries as a power storage system, a secondary market that could bring down the cost of the Volt and other plug-in vehicles for consumers.

For its part, GM is lobbying utilities to offer rebates or cheaper off-peak charging rates and asking for other forms of tax relief to offset development costs expected to keep it from turning a profit on the initial Volt sales.
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Posawatz declined to comment on how much GM would charge for the Volt, saying only that the automaker was certain there was strong enough initial demand to justify a higher price.

"The nature of this technology is that it's going to be expensive, and we will not underprice this vehicle," he said.

GM is designing the Volt to run for 40 miles on a lithium-ion battery pack that can be recharged at a standard electric outlet. The car will also capture energy from braking like a traditional hybrid and feature an on-board engine that will be used to send power to the battery on longer trips.

In the future, GM could offer a battery pack with a 20-mile electric-only range to bring costs down, Posawatz said, part of an effort to cut the cost of such vehicles by half or more.
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GM wants the Volt battery to run at least 150,000 miles and last 10 years. But even after its projected life in the car, engineers estimate that the batteries would still have between 70 percent and 80 percent of their power remaining.

That opens the possibility that a utility could stitch together hundreds or thousands of recycled units to store power and send it back to the electric grid at times of peak demand, GM and supplier executives have said.

Posawatz said California utilities have been particularly interested in that prospect. "They've been very aggressive and they see the bigger picture," he said.
 

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This is great to hear, I'm glad that GM is trying to make these cars as dependable and long lasting as they can, not only to avoid problems down the road, but also for customers. Its great too that they might offer a 20mile battery range model also for a lower end market, and to make it more affordable to make sure that a Volt will be in every drive way in America:)
 

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I think it's a great idea. I think they could eventually have different prices for different ranges of battery packs. That way if someone typically drives less than twenty miles a day they don't have to pay for the unneeded battery distance or carry the unnecessary weight. It would also be nice to be able to easily add a pack to increase distance though. The night before you know that you will be driving a longer distance you could “install” and additional 20mile battery pack and have it charged up by morning. Another benefit to that is if you go to buy a used car in the future and like this particular Volt or whatever car it may be but you want the 40 or 60 mile battery and the car you're looking at has a 20 you could easily add the additional capacity. So much potential I love it.
 

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Its a good idea, but frankly, if you can afford the car at all - you can afford the additional cost for the 40 mile battery, it will pay for itself many times over.

Now, maybe it might make sense for someone with a short commute.

As far as the power grid idea, lithium isn't all that common, I'd rather GM just pay the owner for the battery and recycle it into another e-flex vehicle. Let the power companies use a different battery technology that doesn't have to be lightweight or exceptionally power dense.
 

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The more I hear about these, the more I wonder if a bigger problem with them might end up being bad gas that never gets refreshed cause everyone will you use them primarily for 40 mile or less commutes? Then when they go outside the range the engine won't start because the gas will be old and degraded??
 

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The more I hear about these, the more I wonder if a bigger problem with them might end up being bad gas that never gets refreshed cause everyone will you use them primarily for 40 mile or less commutes? Then when they go outside the range the engine won't start because the gas will be old and degraded??
True, but I would gladly trade that for the problems we have now because of gasoline.
 

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The more I hear about these, the more I wonder if a bigger problem with them might end up being bad gas that never gets refreshed cause everyone will you use them primarily for 40 mile or less commutes? Then when they go outside the range the engine won't start because the gas will be old and degraded??
For gas to go bad, it would have to sit for months, even people who use it mostly for commuting will occasionally make a longer trip. The wise choice would be to only put a small tank, say no more than 10 gallons, so you wouldn't have to go too much further without filling up. Or...maybe some sort of sensor that measures degradation in gas and will start up the engine sooner than it normally would to burn some off. Who knows, but it doesn't seem like something we need to worry too much about.
 

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Guys, GM doesn't let slip something like the 20 mile battery on a project as important as Volt without a good reason.

Do you think that reason is that they want you to know that the Volt can also not go 40 miles? Or is it that they can nearly halve the cost of the Volt by it not going 40 miles but 20 miles?

I think that this statement has more to do with GM not being able to bring down the cost of the battery pack and realising that they will not be able to sell many Volts at $40+K after the first year of rich enviro-leading edge tech buyers who can and do pay through the nose to be first and be seen to be first. Then when Volt sales collapse in year 2 they can offer the 20 mile battery deal to bring the price of the car down to say $25K (as the car itself would sell for say $16K if it were a traditional 1.6 I4 FWD). But by then there will be a 20 mile plug-in Prius on sale to go head to head with.

Food for thought. This may just be GM preparing us for bad news. Up until a month ago GM thought they would have 25% more high profit truck and SUV sales to help subsidise losses on Volt sales. Now they don't have that luxury and only $21 Billion in cash reserves and a burn rate in excess of a billion a month, with $9 billion in debt falling due soon. Things have changed.


;)
 

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Awesome news. Even if you always use the gas engine and never recharge the Volt from your electrical outlet, remember that it will still get very good mileage (~50mpg). If GM sold a stripped Volt getting 50 MPG for around $20K, I still think people would buy one. Given this, anything from a 0 mile battery-only range at $20K up to 40 miles for no more than $40K will sell. The more variants to get to volume profitability, the better.

I hope GM keeps both (all?) battery suppliers on board so that as they reach maximum capacity, Chevy won't be limited by a company unaccustomed to the automotive supply world. That, and it would protect them if one decided to hike up prices or suffered a supply interruption.
 

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Awesome news. Even if you always use the gas engine and never recharge the Volt from your electrical outlet, remember that it will still get very good mileage (~50mpg). If GM sold a stripped Volt getting 50 MPG for around $20K, I still think people would buy one. Given this, anything from a 0 mile battery-only range at $20K up to 40 miles for no more than $40K will sell. The more variants to get to volume profitability, the better.

I hope GM keeps both (all?) battery suppliers on board so that as they reach maximum capacity, Chevy won't be limited by a company unaccustomed to the automotive supply world. That, and it would protect them if one decided to hike up prices or suffered a supply interruption.
As optimistic as you seem to be about this, there are some caveats that need to be considered, and I think many people have not fully thought through what the Volt will be.

The Volt is an 120kW (160hp) electric motor electric car with a range extender engine of 1.0L turbo 3-cylinder for a 53kW (70hp) generator. It's theoretical highway range is 640 miles. However, and even considering that it would be quite a bit lighter with a half battery pack or a small near zero battery pack capable of merely brake regeneration and an accelerating reserve, the Volt is not a car most here would want to drive on gasoline only. It is primarily a commuter car that can also travel sedately and occasionally on a highway for a long trip as well. It is not designed to run beyond 40 miles in stop start city traffic other than as an emergency get-me-home.

You can’t get something for nothing and you can’t get 50 mpg unless you have a small engine in a car the size of the Volt and drive very slowly and timidly, which is all you could do with 70 hp.

Now most here will say, but wait, you have the electric engine to add 160 hp to that and I say, yes – if you are doing highway constant speed most of the time with little acceleration. You can’t have the little 70 hp engine giving the 160hp motor sufficient power for acceleration AND give it a constant 70hp for driving in city traffic. A big chunk of that 70hp has to be going into recharging the battery for the engine to draw 160hp out in stop start driving if it is to feel like a normal car.

So 50hp could go to the wheels for driving in traffic while 20 hp is being banked in the batteries for the next set of lights as regenerative braking alone won’t cut it for American driving styles. People would need to brake much slower so the conventional brakes don’t come into play and accelerate away sedately.

So in real world stop start city traffic running on the range extender engine only will be more like a car with a 90hp IC engine. Not that there is anything wrong with that, as the Europeans and Asians will attest as they do that all the time. But Americans have so far refused to have weak small hp in even their commuter cars. And the Volt engine will be screaming flat out all the time, even at the lights, without relief in order to achieve that 90hp average.

I do not say this lightly so please try to understand. If your Volt battery is low you can start the ICE and run it to recharge for 30 minutes, say before you leave work. In other words; the Volt's ICE will ONLY recharge the battery while the car sits stationary.

If you don't believe me read the excerpt below from gm-volt.com which clearly shows in the graph and in the text that the ICE WILL NOT recharge the battery on the go and the ICE will effectively only provide peak efficiency at 30kW (39hp). Also in order to avoid the little 3 cylinder ICE screaming it's head off, as I pointed out would be a problem, it will run at around just over half throttle and artificially modulate to mimic a conventional engine.

Check out GM's own graph, it shows what I've been saying that the Volt will drag along the bottom of the 30% capacity of the battery using ONLY the ICE running at an effective 39hp to run the car. The Volt WILL DEFINITELY feel like driving a Euro econo car after 40-miles.

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Article from gm-volt.com

Latest Chevy Volt Battery Pack and Generator
Details and Clarifications
Posted in: Battery, Design, Engineering, PHEV

In some recent posts, we were able to find out and discuss some important details about how the Volt’s li-ion battery pack is intended to function. One of the most critical facts we obtained from GM is that the 40 mile all-electric driving range will occur within 50% of the batteries maximum charge, or 8 kWh out of 16 kWh total. This translates to 200Wh/mile of energy consumption.

We also looked at the ability of the combustion engine (53 kW maximum) to keep the battery charged and how it might operate to do so. This generated some very intriguing discussion and further questions.

I went back to GM and had some discussion with other sources familiar with the Volt’s engineering, and have been able to elucidate the following more accurate facts:

As per Rob Peterson, GM spokesman, the battery will operate in the 50% “swing” zone, but actually, the batteries full point will be 80% (not 100%). So its charge state will actually vary between 30% SOC and 80% SOC. This translates to the following analysis of battery capacity:

theoretical capacity 100% 16.0 kWh (not realized under normal conditions)

highest recharged level 80% 12.8 kWh (after being plugged in)

charge sustaining level 30% 4.8 kWh (after ~40 miles of driving)

empty 0% 0.0 kWh (not realized under normal conditions)

In terms of the on-board generator, the peak power of 53 kW will rarely be used, only in extreme conditions. Peak efficiency will be at around 30 kW, which is what the car should require at 65 mph slightly uphill, although the actuals of mass and energy requirements are not final yet.

The engine’s job will be to maintain the battery at a SOC of 30%, and will do so by continuously matching the average power requirement of the car once it is turned on. Those energy requirements will roughly be about 8 kWh in the city, and 25 kWh on the highway.

Another interesting note is about the time course of recharging the battery on the road. If one tried to recharge it by maxing engine output, the cells’ temperature would get too high, so the idea of rapidly “refilling” it on the fly and then cutting off the generator wont apply. Rather, it seems, the engine will continue to run, constantly matching the needs of the car to keep the battery at 30% until you stop driving.

Interestingly, the motor will likely be programmed to increase rpm when you step on the gas and quiet down when you stop to “simulate” the driving effect people are already used to. This will avoid the sudden unexpected ons and offs.



The graph above illustrated how the pack shall operate.

__________________________________________________

So this article confirms exactly what I have been saying, that the Volt's ICE after 40-miles will act exactly like a diesel-electric train with the ICE providing all the power needs of the Volt for driving. And it will do so using mostly 39hp in a 4 seat car that, even though GM is spending lots to make it light, still has a 400 pound battery pack to haul around. And with only a 1.0 litre 3 cylinder turbo engine doing all the work it will be no different to any other small 4 seat small engined Euro econo car that gets 50mpg.

I'm sorry for all the Americans who thought the Volt would let them have their cake and eat it too, but if more of you studied engineering you wouldn't have sustained this level of delusion about the constraints of real world physics. You don't get something for nothing. You don't get 50mph in a Volt after the battery goes flat without the car driving like any other econo car that gets 50mpg.

PS. The reason that GM will not have the ICE recharge the battery on-the-run (apart for the heat build-up issues), and why it will have to wait until you get home to recharge it, is because the life on the battery depends on how many times it has gone through a charge cycle. So a small recharge on-the-run and then a discharge followed by another recharge on-the-run and further discharges all count towards the chemical deterioration that result in charge cycles limiting the life span of the batteries.



;)
 

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The more I hear about these, the more I wonder if a bigger problem with them might end up being bad gas that never gets refreshed cause everyone will you use them primarily for 40 mile or less commutes? Then when they go outside the range the engine won't start because the gas will be old and degraded??
I'm wondering if the Volt won't have a little reservoir under the hood or in the trunk that holds fuel stabilizer, and based on the last fill-up, or fuel usage, would dump the stabilizer into the fuel tank?

Either that, or the engine would go into an auto-cycle mode based on hours since last used that would run the engine just enough to ensure that the fuel wouldn't go bad. Just thinking out loud.
 

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As optimistic as you seem to be about this, there are some caveats that need to be considered, and I think many people have not fully thought through what the Volt will be.

The Volt is an 120kW (160hp) electric motor electric car with a range extender engine of 1.0L turbo 3-cylinder for a 53kW (70hp) generator. It's theoretical highway range is 640 miles. However, and even considering that it would be quite a bit lighter with a half battery pack or a small near zero battery pack capable of merely brake regeneration and an accelerating reserve, the Volt is not a car most here would want to drive on gasoline only. It is primarily a commuter car that can also travel sedately and occasionally on a highway for a long trip as well. It is not designed to run beyond 40 miles in stop start city traffic other than as an emergency get-me-home.

You can’t get something for nothing and you can’t get 50 mpg unless you have a small engine in a car the size of the Volt and drive very slowly and timidly, which is all you could do with 70 hp.

Now most here will say, but wait, you have the electric engine to add 160 hp to that and I say, yes – if you are doing highway constant speed most of the time with little acceleration. You can’t have the little 70 hp engine giving the 160hp motor sufficient power for acceleration AND give it a constant 70hp for driving in city traffic. A big chunk of that 70hp has to be going into recharging the battery for the engine to draw 160hp out in stop start driving if it is to feel like a normal car.

So 50hp could go to the wheels for driving in traffic while 20 hp is being banked in the batteries for the next set of lights as regenerative braking alone won’t cut it for American driving styles. People would need to brake much slower so the conventional brakes don’t come into play and accelerate away sedately.

So in real world stop start city traffic running on the range extender engine only will be more like a car with a 90hp IC engine. Not that there is anything wrong with that, as the Europeans and Asians will attest as they do that all the time. But Americans have so far refused to have weak small hp in even their commuter cars. And the Volt engine will be screaming flat out all the time, even at the lights, without relief in order to achieve that 90hp average.


;)
Monaro, have you ever driven an electric car? I have only ridden in one many, many years ago..but from my knowledge of electric motor torque bands (max torque immediately) and several articles I have read specific to the ev1 and other electric cars, it seems that your posting is trying to compare apples to oranges. Because electric motors are significantly more efficient than an internal combustion engine(ICE), all the power goes to making the car go and not to heat and drivetrain losses. As such, the 160 hp will feel significantly more powerful than an equivalent engine with the same output. The most memorable example is an article on the EV1 in a magazine where the author out accelerated a Mustang. Now I can't disagree with you about the lack of care with which we here in America accelerate and brake. Accelerating to a light and slamming on the brakes will need to become a thing of the past if people really want their cars to become more fuel efficient, regardless of the fuel. However, the fact that the volt will be all electric, I think that the driving experience with the provided battery/ICE generator combination will have a drivability and feel a lot closer to a standard car such as a Malibu and not feel like the gutless economy cars of europe.
 

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the ev1 out accelerating may be based more on the torque, than anything else. electric motors are a beast off the stop. their torque curve consistently drops off throughout rpm range, more significantly than a gas engine.

as for the theory that most of the engine horsepower would go towards keeping the car moving at highway speeds, i'm not sure that i buy that. in a hybrid system like a prius, yeah. with the motor decoupled in the volt, the only time it runs should be to charge the the battery. based on the recharge times quoted (believe it was 20 min while driving) the generator is applying a much greater charge than the engine alone will eat at the time. granted, recharging will be slower at highway speeds, but it shouldnt' be as much of a dog as predicted.
 

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Its a good idea, but frankly, if you can afford the car at all - you can afford the additional cost for the 40 mile battery, it will pay for itself many times over.
Uhh, not necessarily. Lithium ions are massively expensive. And the Volt has 400 lbs worth of the stuff. I wouldn't be surprised if lowering the range 20 miles would lower the price $10,000 or more.

Batteries are the reason the EV1 cost $80,000 to make. And why the Tesla costs $100,000.
 
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