IL Corrects Volt Story: Batteries Will NOT Charge When Driving; GM Website Differs

[GMusa]

Ok im really confused here.. this is directly from the Chevy website.

"Unlike traditional electric cars, Chevy Volt has a revolutionary propulsion system that takes you beyond the power of the battery. It will use a lithium-ion battery with a variety of range-extending onboard power sources, including gas and, in some vehicles, E85 ethanol(3) to recharge the battery while you drive beyond the 40-mile battery range. And when it comes to being plugged in, Chevy Volt will be designed to use a common household plug."

Heres the link to the web page - http://www.chevrolet.com/electriccar/

So is this thing going to be able to recharge while driving?? The way GM/Chevy states it on the Chevy web page it makes one think that the engine will recharge the batteries while driving.

[FenwickHockey65]

Originally Posted by GMusa

Ok im really confused here.. this is directly from the Chevy website.

"Unlike traditional electric cars, Chevy Volt has a revolutionary propulsion system that takes you beyond the power of the battery. It will use a lithium-ion battery with a variety of range-extending onboard power sources, including gas and, in some vehicles, E85 ethanol(3) to recharge the battery while you drive beyond the 40-mile battery range. And when it comes to being plugged in, Chevy Volt will be designed to use a common household plug."

Heres the link to the web page - http://www.chevrolet.com/electriccar/

So is this thing going to be able to recharge while driving?? The way GM/Chevy states it on the Chevy web page it makes one think that the engine will recharge the batteries while driving.

That's what I thought as well...

GM better clear this up or there's going to be some negative publicity...

[chevydlrmn]

If the gas engine powers the electric motor, or recharges the batteries, is it not still as electric only as it was before this silly post. Is it not still electric drive since the electric motor is powering the wheels, coming from batteries powered by engine or motor powered by engine?

[AMERICA 123]

There two ways this can go - and some variations within one.

Either way , Edmund's article - and this thread's title are wrong - its a miscorrection at best.

They are for sure wrong because regenerative braking is definitely part of it.

So, the batteries will be charging while driving - at least from that - in almost all scenarios.

Worth noting, with greater capacity than the Prius.

What really matters after initial charge depletion are the results and not the details of the method per se.

Most likely there are several 'modes' this thing runs in and whatever the case, you can bet your bottom dollar that GM evaluated all that and is going with what works best.

If the vehicle has a 40 mile plug in range and achieves excellent fuel economy from that point on with decent or acceptable performance then we're there.

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

Personally, since it somewhat appears more certain that the Volt is not going to be dependent on a heavy - constant IC battery recharging stratagem I'd be really glad to see this 'story' pan out - nothing out there is more inefficient than recharging a battery pak with a gasoline generator set and then running the power out to the wheels from the battery.

Basically this is a sort of good news not bad - it means GM's getting good results with the IC to wheel portion of the PT - and the regen system and use.

[rob2299usa]

Wow... ok, there is a ton of misconceptions in this thread. Ok here's my try at explaining this:

On ANY E-REV vehicle the point is to MINIMIZE fuel usage. You never want to use a drop of fuel more than you need to. For this reason, the gas engine in the Volt will be used only to maintain the minimum state of charge of the battery (in this case 30%). Charging the battery off of gasoline energy is not only less efficient than plugging it in, it completely defeats the purpose of this vehicle. Ideally you want to arrive at your destination with the batteries fully depleted so that you can maximize your off the grid energy usage.

The other point is battery life. You never want energy from the gas engine going "through" the battery. Not only are you suffering losses in energy due to the battery heating up (ever felt your cellphone or laptop battery after a good charge??), but you would also be needlessly cycling the battery. We should all know that batteries have a finite amount of charge/discharge cycles from our cellphone and laptop batteries dying after 6 months or whatever. It is MUCH more efficient to power the drive motor directly off of the energy coming from the generator connected to the gas engine.

Also, whoever said that "once you get to 600 miles your trip is done before you plug in again" is dead wrong. As long as you keep gasoline in the tank, the car will be able to continue to drive. Doing this often, however, would be stupid because then you're not taking advantage of the cheaper electric energy.

The author of that article does not know what he's talking about. Typical media... they just have no grasp of technology like this. The battery once depleted is not 400 lbs. of uselessness. It will be used as a buffer for high demand situations where additional energy is needed than the engine can provide, and it will also be used as a energy storage medium for regen. Theoretically you could regen enough if you were going down hill to kick back into engine off / ev mode so I would assume it will work something like that.

[MonaroSS]

Originally Posted by WishIhadatruck

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

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

WishIhadatruck, thanks mate for remembering that.

I explained how it all worked in detail and nobody in that thread believed a word I said......

[urarock76]

Thanks for the post rob2299usa, but your info didn't clear this up for me. I thought the point of the gas engine was that it would be run at a constant, optimum rev while on. If that is so, isn't a whole bunch of gas energy going to be wasted when the Volt is stopped or traveling slowly and not using all the energy the engine is generating? Second, if the point of not charging the batteries with the engine is to reduce the charge/discharge cycles (a worthy endeavor), how does that true up with the use of regenerative brakes to charge the battery during engine on time...or is it that the regenerative brake system is turned off when the gas engine is on? Finally, not from your post, but other posters have said that while in engine only mode the car will get 50mpg? Is that true? That seems pretty high given GM's current models do not come close to that, and they don't carry the extra battery weight.

[edsuski]

Originally Posted by Mcmflow

I think we need to hear something offical......if this is true.....what a waste, I would never spend $35-40K for this

Why in the world would this be a "waste"? You do NOT want to use a 30% efficient gas motor to charge the battery. 78% of us will not use the ICE at all for commuting to and from work. When one needs to travel more than 40 miles - the ICE will kick in and burn just enough fuel to drive the generator enough to provide electricity to the electric motor. When you get to a plug - you can recharge over night. This is the most efficient way to power the Volt. Uses the least fuel and creates the least amount of pollution.

Charging the batteries with a 30% efficient internal combustion engine makes no sense.

[stormwatcher]

Originally Posted by edsuski

Charging the batteries with a 30% efficient internal combustion engine makes no sense.

Well, how much sense does it make using a 30% efficient ICE to drive the generator? How efficient is that?

What type of mileage can be expected when powered by the ICE as many trips could well be over 40 miles?

[AMERICA 123]

Originally Posted by MonaroSS

WishIhadatruck, thanks mate for remembering that.

I explained how it all worked in detail and nobody in that thread believed a word I said......

Because many of your estimates were way wrong as well as your way of thinking it thru.

Quite frankly seemed you were more interested in trying to prove GM didn't know what they were doing more than anything else

Some of the stuff you put up from third party sources was in fact verbatim Toyota material - the old stuff they used when they originally justified the HSD system - and later material when they were defending their at the time decision not to do a PHEV - obviously since reversed - sorta.

[AMERICA 123]

Originally Posted by stormwatcher

Well, how much sense does it make using a 30% efficient ICE to drive the generator? How efficient is that?

- Much better than wasting energy - and 'experiencing' certain types of efficiencies putting it into the battery and then pulling it out .

Don't get confused by all the misinformation concerning HSD etc.

There are many measurements of efficiency that are not good in that PT - but their effects and inefficiencies are overcome by ( primarily) capturing enough brake energy so that in total it comes out ahead . ( with the right duty cycle etc ).

The Volt offers a stronger regen ability plus the advantage of a strong PHEV capability.

[AMERICA 123]

Originally Posted by YupYupYup

EPA testing rules, people...

Writer is so anti-GM it is sad...No wonder nobody respects journalists.

Thats pretty much it. Now look at the enhanced confusion.

[MonaroSS]

Originally Posted by AMERICA 123

Because many of your estimates were way wrong as well as your way of thinking it thru.

Quite frankly seemed you were more interested in trying to prove GM didn't know what they were doing more than anything else

Some of the stuff you put up from third party sources was in fact verbatim Toyota material - the old stuff they used when they originally justified the HSD system - and later material when they were defending their at the time decision not to do a PHEV - obviously since reversed - sorta.

Don't worry I'm patient. It will all prove to come my way in time. When you are correct the slow blossoming of truth is a thing to be savoured.....

And it wasn’t that GM didn’t know what they were doing, but that the accelerated program made them aware of limitations one after the other they needed to jerry-rig around as they learnt new things.

[eaton53]

On ANY E-REV vehicle the point is to MINIMIZE fuel usage.

Only an utter fool would actually want the engine to charge the batteries.
All you want is just enough to keep things moving along until you can plug in again.

[rob2299usa]

Originally Posted by urarock76

Thanks for the post rob2299usa, but your info didn't clear this up for me. I thought the point of the gas engine was that it would be run at a constant, optimum rev while on. If that is so, isn't a whole bunch of gas energy going to be wasted when the Volt is stopped or traveling slowly and not using all the energy the engine is generating? Second, if the point of not charging the batteries with the engine is to reduce the charge/discharge cycles (a worthy endeavor), how does that true up with the use of regenerative brakes to charge the battery during engine on time...or is it that the regenerative brake system is turned off when the gas engine is on? Finally, not from your post, but other posters have said that while in engine only mode the car will get 50mpg? Is that true? That seems pretty high given GM's current models do not come close to that, and they don't carry the extra battery weight.

stopped = engine off for sure. also i would imagine that the engine can run at a point low enough to just keep the vehicle moving. if you were coasting down a hill, then the engine would probably shut off. regenerative braking is not engine power, therefore that energy WOULD be used to charge the battery. That's why I said that I imagine a situation (mountain driving) where you get enough regen to switch the engine off and drive another small distance in engine off mode.

i imagine it is definitely possible to get 50mpg due to the superior aerodynamics, the ability to regenerate energy from braking, engine stop/starts, and the fact that you only run the engine at a few efficient points.