GM Chevy Volt

[Saghost]

I only just realized that, and my disappointment over what was supposed to be GM's entry in to the EV market grew substantially... I thought someone had finally figured out how to build a hybrid at least, but it appears even that was too much to ask for. I used to think Tesla was 10 years ahead of the competition... I'm starting to realize it's even more.

How exactly does GM's decision to improve the fuel economy during certain portions of the gas powered extended range drive harm you or the car in any way?!? I've seen a few folks say things like you did (mostly in 2011...) - but none have been able to explain this one.

It doesn't make the engine run when you could otherwise be driving on electricity. It doesn't add weight to the Volt. It doesn't make the car less completely electric for the majority of the miles that are driven on battery. As implemented, it doesn't even allow the car to drive without electricity under any circumstance.

So why would anyone be disappointed that GM found a way to stretch their gas 10% further? You'd think using less gas for the same task would be a good thing...

(Notice how the 30% lighter, narrower but slightly taller i3 REx gets only 2 mpg (<5%) better in EPA testing despite being rated as ~20% more efficient on battery power? Although the engine is adjacent to the electric motor, it adheres to your non-sensical standard and does not allow the engine to provide power mechanically.)
Walter

 

[JRP3]

The engine and gas tank in my Volt aren't presently designed to be routinely removed and put back either. I see no reason why it couldn't be designed to support that even though it's impractical in reality. Similarly, the Model S pack could be redesigned to allow almost 1/3 of it to be removed when not needed for routine commuting. In both cars you would probably drop about 300-400 pounds.

The extra power and performance provided by that removable section is not used by many drivers on routine commutes. I'm frequently surrounded by Teslas whenever I'm on the road since I live in San Francisco and work in Silicon Valley. I never see them accelerate faster than 200 kW worth of power. Removing that section of the pack would reduce an 85 kWh pack down to a 60 kWh pack. Less weight. Increased efficiency. It's all doable but nobody would actually want to do it on their car. It's rhetorical.

As for battery life, it probably would put a little extra stress on the permanent 60 kWh section but the removable section would have no stress and could be stored at 30-40% SOC in a cool environment so it would calendar age slowly. Or, you could put it to work as stationary storage for your home in order to save money through buying all your utility grid power at off-peak rates and reinstall it in your car for vacation road trips when you are using little power at home. If and when the 60 kWh portion needs replacing it would be cheaper to replace than an entire 85 kWh pack....

I assume you're joking since not only would it be impractical it would also severely unbalance the pack and cause a nightmare for the BMS. My point was simply that the entire battery pack in an EV is always being used to move the vehicle, even if it's not being drained near zero. Your argument is more along the lines of buying the smallest battery pack you need, which is fine, but not relevant. One could similarly argue that no cars need more than 4 cylinders, but an 8 cylinder engine in a car is still using all components to move the vehicle even when not under full power, and since it's more lightly loaded should theoretically last longer than a smaller engine.

 

[ggies07]

How exactly does GM's decision to improve the fuel economy during certain portions of the gas powered extended range drive harm you or the car in any way?!? I've seen a few folks say things like you did (mostly in 2011...) - but none have been able to explain this one.

It doesn't make the engine run when you could otherwise be driving on electricity. It doesn't add weight to the Volt. It doesn't make the car less completely electric for the majority of the miles that are driven on battery. As implemented, it doesn't even allow the car to drive without electricity under any circumstance.

So why would anyone be disappointed that GM found a way to stretch their gas 10% further? You'd think using less gas for the same task would be a good thing...

(Notice how the 30% lighter, narrower but slightly taller i3 REx gets only 2 mpg (<5%) better in EPA testing despite being rated as ~20% more efficient on battery power? Although the engine is adjacent to the electric motor, it adheres to your non-sensical standard and does not allow the engine to provide power mechanically.)
Walter

You know why? Because they shouldn't be focused on making the engine better, they should be focued on making the battery better! Thats why. They should be pushing foward, but they are not.

This is trying me nuts. Its not 2010 anymore. Someone one-upped them (Tesla) and came out with an amazing electric car. Where's the competition from GM? I posted a link days ago in this thread that said they are not going to push the Volt and just make it a niche market.

 

[dhrivnak]

I posted a link days ago in this thread that said they are not going to push the Volt and just make it a niche market.

The reason for this is few people are buying plug-ins. Yes we believe but plug in sales last month were nowhere near 1% of auto sales. If people buy they will build. But few people are buying. Now that gasoline prices appear to be falling even fewer will buy plug ins.

And it is not just GM no EV'S have really caught on. Yes the Model S is a great car but it's sales are WELL behind the sales of any major car line. It looks like the auto industry will sell 15 million cars this year and not sure even 100,000 will have a plug and only about 45,000 will be full battery.

GM is selling to the market. And a market that is skewed due to tax credits and HOV passes.

 

[Jeff N]

You know why? Because they shouldn't be focused on making the engine better, they should be focued on making the battery better! Thats why. They should be pushing foward, but they are not.

This is trying me nuts. Its not 2010 anymore. Someone one-upped them (Tesla) and came out with an amazing electric car. Where's the competition from GM? I posted a link days ago in this thread that said they are not going to push the Volt and just make it a niche market.

If they are making plugin hybrids like the Volt that still often spent 1/3 of their miles driving on gasoline then, yes, I think they should spend a little time integrating their newer engine technology into the platform.

They are serious about batteries. They have built one of the largest battery testing facilities in the world in Michigan. They are actively investing in battery startups. They are even doing some of their own battery chemistry and design R & D like a practical and effective way to build silicon-enhanced carbon anodes with high cycle lifetimes that they developed a year ago.


Here's part of a Wall Street Journal article 5 days ago:

"We are definitely working on making a 200-mile-range battery electric vehicle at around the $30,000 to $35,000 price target," said Prabhakar Patil, the chief executive officer of LG Chem Power Inc., a U.S.-based research arm of the South Korean battery company.
"It's more than a possibility."....

GM, which contracts with LG Chem to supply the Chevrolet Volt plug-in hybrid, has said it plans to introduce a 200-mile range electric vehicle starting as low as $30,000.
A GM official said the project is on track, although he declined to offer details on the timing. Former CEO Dan Akerson first mentioned the vehicle last year.

Similarly, GM invested in and worked with Envia last year in an attempt to bring to market cheaper and more energy-dense batteries within the 2017 timeframe but the effort failed due to some apparently fraudulent claims by Envia that eventually unraveled.

Last week GM filed a trademark application for the name "Chevrolet Bolt" which seems like a possible name for a new BEV.

GM shows multiple signs of seriously working on improved near-term battery technology with an intent on building long-range all-electric vehicles -- certainly far more serious intent than Ford, Honda, Toyota, Chrysler-Fiat.

 

[ggies07]

Here's part if a Wall Street Journal article 5 days ago:

Similarly, GM invested in and worked with Envia last year in an attempt to bring to market cheaper and more energy-dense batteries within the 2017 timeframe but the effort failed due to some apparently fraudulent claims by Envia that eventually unraveled.

Last week GM filed a trademark application for the name "Chevrolet Bolt" which seems like a possible name for a new BEV.

GM shows multiple signs of seriously working on improved near-term battery technology with an intent on building long-range all-electric vehicles -- certainly far more serious intent than Ford, Honda, Toyota, Chrysler-Fiat.

ah, well there ya go. Good to hear. I knew about Envia, but didn't know about this new update. I hope it works out this time.....

 

[Jeff N]

I assume you're joking since not only would it be impractical it would also severely unbalance the pack and cause a nightmare for the BMS.

Yes, I am joking and no it would not necessarily be a problem with the BMS or balancing. The 25 kWh detachable pack can be balanced separately from the "permanent" main pack much like a future Tesla could have a two-level battery (one power-dense Lithium-ion pack combined with an energy-dense Lithium Air pack that keeps the Lithium-ion pack charged). But, yes, I am joking.

 

[dsm363]

Yes, I am joking and no it would not necessarily be a problem with the BMS or balancing. The 25 kWh detachable pack can be balanced separately from the "permanent" main pack much like a future Tesla could have a two-level battery (one power-dense Lithium-ion pack combined with an energy-dense Lithium Air pack that keeps the Lithium-ion pack charged). But, yes, I am joking.

How exactly would this work. A swap station? Seems easier to simply carry around extra kWh and charge.

 

[Jeff N]

How exactly would this work. A swap station? Seems easier to simply carry it around and charge.

Agreed, just as it would be easier and more practical to carry around an ICE and gas tank on regular commuter days when they aren't needed for longer distance driving. So it's a silly argument to say that plugin hybrids like the Volt are a poor design because they are wastefully carrying around unnecessary gasoline propulsion when driving electric.

 

[dsm363]

Agreed, just as it would be easier and more practical to carry around an ICE and gas tank on regular commuter days when they aren't needed for longer distance driving. So it's a silly argument to say that plugin hybrids like the Volt are a poor design because they are wastefully carrying around unnecessary gasoline propulsion when driving electric.

But power is related to size of pack in kWh. Could the P25kWh still go 0-60 in 4 seconds? Don't think it would.

Your analogy doesn't quite work. The Volt isn't a poor design because it has an ICE but if you never ever use it then why have it.

 

[JRP3]

Also a smaller pack slows down your charging speed, so there is that as well.

 

[Jeff N]

But power is related to size of pack in kWh. Could the P25kWh still go 0-60 in 4 seconds? Don't think it would.

First, few commuters go 0-60 at a 4 second acceleration rate. I've been in a Model S who's driver did that to show off the car for grins but I've never seen anyone do that on my long commute and I probably see a dozen Teslas a day on highway and city streets.

Second, with the silly detachable 25 kWh pack removed you would be driving a 60 kWh Model S and I haven't seen many complain that it is underpowered for daily commute purposes. With the 25 kWh pack installed you would be back to having a full 85 kWh pack with 300-400 kW of output.

- - - Updated - - -

Also a smaller pack slows down your charging speed, so there is that as well.

Somewhat, but only when supercharging with 60 kWh and in any case not too many people depend on supercharging for the regular daily commute when they would have this silly 25 kWh pack detached and stored outside their car. After being re-installed for a road trip you would be back to having 85 kWh and could charge at full speed.

 

[qwk]

How exactly do you detach and reattach a 300-400 lb section? Where does one put it? This is a pretty bad idea.

If you want/need only a smaller pack, buy a car with one. With 30k miles of 85kwh pack driving, I want a bit more, not less. 100-120kwh would be the sweet spot for me.

 

[Jeff N]

How exactly do you detach and reattach a 300-400 lb section? Where does one put it? This is a pretty bad idea.

If you want/need only a smaller pack, buy a car with one. With 30k miles of 85kwh pack driving, I want a bit more, not less. 100-120kwh would be the sweet spot for me.

I think you are missing the full context -- go back 2-3 pages to see where this silliness started. It is not a serious proposal.

 

[stopcrazypp]

I think you are missing the full context -- go back 2-3 pages to see where this silliness started. It is not a serious proposal.

From what I got from this discussion, the ICE system is just extra weight while a "EREV" is in EV mode, but extra battery capacity is still serving a useful function (more discharge / charge power and less battery stress). Actually the Volt illustrates the point quite well, it only uses about 10kWh out of a 16kWh battery, but the 6kWh that is not "usable" still serves an important function for the rest of the pack.

 

[dsm363]

From what I got from this discussion, the ICE system is just extra weight while a "EREV" is in EV mode, but extra battery capacity is still serving a useful function (more discharge / charge power and less battery stress). Actually the Volt illustrates the point quite well, it only uses about 10kWh out of a 16kWh battery, but the 6kWh that is not "usable" still serves an important function for the rest of the pack.

Exactly. Not even a good analogy that is attempted here right Volt extra weight vs Model S.

 

[dsm363]

First, few commuters go 0-60 at a 4 second acceleration rate. I've been in a Model S who's driver did that to show off the car for grins but I've never seen anyone do that on my long commute and I probably see a dozen Teslas a day on highway and city streets.

Second, with the silly detachable 25 kWh pack removed you would be driving a 60 kWh Model S and I haven't seen many complain that it is underpowered for daily commute purposes. With the 25 kWh pack installed you would be back to having a full 85 kWh pack with 300-400 kW of output.

So you point is that if it's something that isn't done on a normal commute we shouldn't have it?

The detachable pack is not really a good idea. Tesla would have to totally redesign the pack system and build out swap stations at a higher cost than Superchargers. Sure carrying around extra battery capacity is 'wasteful' but so is driving a car that seats 5 when you drive yourself to work. Why not get a tiny two seater econobox with a 2 stroke law mower engine for your commute? Would be less wasteful.

 

[Breezy]

No one, ever....is going to drive more electric miles in a Volt, than they would in a vehicle that is a true EV.

Chevy Volt Owners Drive More Electric Miles Than Nissan Leaf Drivers: Why?

 

[Doug_G]

Right then, I have moved a boatload of posts - probably not enough - over to the Pure BEV Dogma thread. If you feel your post was inappropriately moved, well... too bad. This is such a huge mess that I don't have the time to unravel it. If people are better behaved then moderation will be lighter.

No more arguments about PHEV or EREV terminology in this thread. Period.

Also the terminology argument was starting to get snippy. We do not tolerate personal attacks on the forum. Please keep it civil.

For the record, it has been settled that the engine does indeed drive the Volt's wheels if the car calculates that it is more efficient to do so. Discussions about the conditions under which this happens are reasonable; however, the moderators will be watching for signs of devolution into silly terminology arguments!

 

[richkae]

My biggest obstacle to purchasing a Volt is the lack of a 5th seat.
Does anybody think that GM is going to fix that in the next version?