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I have to leave my car outside tonight and can't plug in on a 200 mile road trip. Should I save some battery for the night or is it ok to leave it parked overnight in temps form 0-10 degrees with a depleted battery?
 

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I have to leave my car outside tonight and can't plug in on a 200 miles road trip. Should I save some battery for the night or is it ok to leave it parked overnight in temps form 0-10 degrees with a depleted battery?
You won't damage the battery, the car won't let it get so far depleted that it will hurt it. The main issue with cold lithium ion batteries is they can't provide much power.

What you might find is it engages "deep cold ERDTT mode", which basically makes the car drive on gas power until the battery is warmed up enough to provide power. It will drive a little differently in that mode (feels more like an ICE car than a hybrid and regen braking might be disabled).
 

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I have to leave my car outside tonight and can't plug in on a 200 mile road trip. Should I save some battery for the night or is it ok to leave it parked overnight in temps form 0-10 degrees with a depleted battery?
It's not temp related, but when I take long road trips I run it on Mountain Mode at the end so that I have some battery available on the streets.
 

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You won't damage the battery, the car won't let it get so far depleted that it will hurt it. The main issue with cold lithium ion batteries is they can't provide much power.

What you might find is it engages "deep cold ERDTT mode", which basically makes the car drive on gas power until the battery is warmed up enough to provide power. It will drive a little differently in that mode (feels more like an ICE car than a hybrid and regen braking might be disabled).
And, eventually, there's the "Battery too cold, plug in to warm" message. But that requires the HV battery to be cold-soaked to below -17F or something, and it would take a lot colder than that to do it only overnight. The battery is a huge thermal mass and it's moderately well-insulated in the cabin tunnel.
 

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And, eventually, there's the "Battery too cold, plug in to warm" message. But that requires the HV battery to be cold-soaked to below -17F or something, and it would take a lot colder than that to do it only overnight. The battery is a huge thermal mass and it's moderately well-insulated in the cabin tunnel.
I had my Gen I Volt sit unplugged in an airport parking lot for four days with zero EV range in temperatures as low as -26F overnight. Fired up with no problems.

I believe the battery too cold plug in to warm message comes on when the cells are cooled below -22F.
 

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It's not temp related, but when I take long road trips I run it on Mountain Mode at the end so that I have some battery available on the streets.
Do you find that your MM approach is more efficient than just running in CS mode on the streets? Have you experimented?
 

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Do you find that your MM approach is more efficient than just running in CS mode on the streets? Have you experimented?
I use MM on the highway where the engine is most efficient and more importantly the engine noise isn't noticeable. At low speeds there is a noticeable difference in noise between the battery and the ICE.
 

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Do you find that your MM approach is more efficient than just running in CS mode on the streets? Have you experimented?
Oh no, not another try at volting!!! No, MM is not more efficient than CS mode. I have tried many times and couldn't find any situations which worked.

(in before the lock)
 

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Oh no, not another try at volting!!! No, MM is not more efficient than CS mode. I have tried many times and couldn't find any situations which worked.

(in before the lock)
Intuitively, I think that on very long trips setting the threshold higher at which CS mode is engaged, in order to have a battery reserve at the end to use at low speed, may actually be more efficient. How much more efficient and how long a trip is needed are the variables that make me conclude that the pennies saved ain't woyth it. I've tried this experiment in the past and just don't think that there is that much to be saved (but no hard data). I do agree that having a quiet ride may make it worth doing for those who are really annoyed with the occasional running of the generator when driving in town. To each his own...:p:confused::cool:
 

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I forgot to plug my car in overnight and still had three bars left on the battery. I park mine outside and it was 17 degrees F this morning. When I started it, the gas engine turned on even though I have the ERDTT set to 15 degrees. The dash showed the battery as empty in the top left corner but still showed how many miles it had left. The engine ran for a few minutes and then the car switched back to battery power with the dash returning to normal with the green battery gauge. I was surprised the engine had to run but I didn't mind since the heat felt good.
 

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I forgot to plug my car in overnight and still had three bars left on the battery. I park mine outside and it was 17 degrees F this morning. When I started it, the gas engine turned on even though I have the ERDTT set to 15 degrees. The dash showed the battery as empty in the top left corner but still showed how many miles it had left. The engine ran for a few minutes and then the car switched back to battery power with the dash returning to normal with the green battery gauge. I was surprised the engine had to run but I didn't mind since the heat felt good.
This is a situation where the car needed to quickly warm the batteries before it allowed you to discharge them. It's perfectly normal in colt temps. Had you plugged the car in, the batteries would have been kept warm all night. If you ever just hang out with the car, you'll hear it do all sorts of whirring and pumping throughout an evening.
 

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I forgot to plug my car in overnight and still had three bars left on the battery. I park mine outside and it was 17 degrees F this morning. When I started it, the gas engine turned on even though I have the ERDTT set to 15 degrees. The dash showed the battery as empty in the top left corner but still showed how many miles it had left. The engine ran for a few minutes and then the car switched back to battery power with the dash returning to normal with the green battery gauge. I was surprised the engine had to run but I didn't mind since the heat felt good.
It's by design.
http://gm-volt.com/forum/showthread.php?152121-Engine-running-due-to-battery-temp-observations

Unusual for it to happen above ERDTT threshold, but it was likely colder overnight and outside just warmed to 17F, but your battery was still below -10C.
 
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