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Keep it plugged in if you can. It will automatically run the a/c to cool the battery and keep it healthy (if it's only for a few days). If you were to leave it for months at a time, from my understanding you should park it with the battery at 50% and leave it unplugged.
 

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Keep it plugged in if you can. It will automatically run the a/c to cool the battery and keep it healthy (if it's only for a few days). If you were to leave it for months at a time, from my understanding you should park it with the battery at 50% and leave it unplugged.
The car will cool it's battery when necessary, whether it's plugged in or not - Doesn't it seem really odd that anyone would recommend leaving it plugged in for 'a few days' yet leaving it unplugged for 'months at a time'?

Don
 

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Except no one has ever produced any documentation or evidence of a Volt's battery temperature management system (TMS) cooling the battery pack when the Volt was not plugged in.
 

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The car will cool it's battery when necessary, whether it's plugged in or not - Doesn't it seem really odd that anyone would recommend leaving it plugged in for 'a few days' yet leaving it unplugged for 'months at a time'?

Don
The logic I've heard with leaving it unplugged is that lithium-ion batteries like to be at 50% charge. The higher the charge, the more temperature sensitivity, and the lower the charge, the less temperature affects the cells. Lithium-ion batteries don't like to sit at 100% charge; it's why Tesla has an option to limit how much the battery recharges for days when you don't need the full battery capacity (such as your daily commute).

If you leave it plugged in all the time, yes, it will run the cooling system and such. It's just for long-term storage, the lithium-ion batteries will prefer to be at 50% SOC rather than the ~80% limit the Voltec powertrain keeps it at when "full".

I've left my car for a week before and just left it plugged in. If I were to do longer than that, personally I'd leave it unplugged and around 50% charge. It's probably insignificant whatever you do because of the meticulous design of the battery protection systems, but it helps me sleep at night :)
 

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The logic I've heard with leaving it unplugged is that lithium-ion batteries like to be at 50% charge. The higher the charge, the more temperature sensitivity, and the lower the charge, the less temperature affects the cells. Lithium-ion batteries don't like to sit at 100% charge; it's why Tesla has an option to limit how much the battery recharges for days when you don't need the full battery capacity (such as your daily commute).
I agree with that. On our Mitsu EV's the factory recommends 30 to 35% for long term storage

I try to fully recharge our '17 Volt the night before I need to drive it - Only use it once a week or so. It sits in the garage with a half charge or less most of the time

I have a friend with a Model S P85 which he has never once fully recharged and he's got about 85K on it now

Lots of folks have their own theories on the car and feeding of Lithium packs

Don
 

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so when the screen shows 1/2 full the battery is really about 35 %
you may have to charge it a bit to get to the happy lithium 50 % level.

I am going to go cut each end off a blanket and see if the middle is still in the same spot
 

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The logic I've heard with leaving it unplugged is that lithium-ion batteries like to be at 50% charge. The higher the charge, the more temperature sensitivity, and the lower the charge, the less temperature affects the cells. Lithium-ion batteries don't like to sit at 100% charge; it's why Tesla has an option to limit how much the battery recharges for days when you don't need the full battery capacity (such as your daily commute).
Keep in mind the GM engineers designed it such that when you show 100% SOC, you aren't at the top of the battery's capacity. Same with the bottom end, there's still more charge left when you show 0 miles left on the GOM and you've flipped to gas.
 

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Except no one has ever produced any documentation or evidence of a Volt's battery temperature management system (TMS) cooling the battery pack when the Volt was not plugged in.
Except I heard mine come on when it wasn't plugged in. Same sound it makes when I plug it in and charging the battery. It's warm (80) but not that warm. Only heard it the once though (so far), had the car almost three months.
 

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sure the noise was not the vacuum pump for the fuel emission system.

or a cicadas :)
 

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sure the noise was not the vacuum pump for the fuel emission system.

or a cicadas :)
Not sure what that sounds like or where it comes from or why it would come on. The car had been sitting there for some time, it's not like it had just been used. I do know it sounds just like the whirring sound the car makes when I'm charging it.
 

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How long will you be letting it sit?
Five full calendar days
In June I took a trip overseas for 11 days, and left the Volt in the driveway plugged in charging at 8 amps. It's been a very hot summer and I wanted to make sure the battery would be properly cooled. Here's what my owner's manual says:

Vehicle Storage

Up to four weeks
. Plug in the high voltage battery
charge cord if temperatures will
exceed 35°C (95°F) and keep
the 12-volt battery cables
connected.

Fun fact: After 5 days my Volt must have put itself to sleep because it quit sending data to Volt Stats. Then on day 9, I checked up on vehicle status from France using the app on my iPhone. This seemed to wake it up and it started sending data to Volt Stats again.
 

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For just 5 days I would leave it plugged in. I have left mine plugged in for over 2 months, on the belief that it would cool itself during the summer months, but lately I have read that it will only do this for a week or so. After that it won't cool the battery even if it is plugged in. So if I ever have to leave it for more than a week in the future I will drain it to about 50% and leave it unplugged.

I also usually put a "battery tender jr" on the 12V battery, but for only 5 days I don't think that would be needed.

As a result of spending a lot of time away from home in the past, I have only about 25K miles on my 2013. It still feels like a new car.

The battery had been getting around 9.8 kwh / 42 miles per charge but in the last week or so I ran it all the way to zero before recharging a couple of times and yesterday I was up to about 10.3 kwh 44 miles used when I pulled into the garage, with 3 miles remaining. That's with A/C running on ECO set to 73 degrees the whole time. Pretty good for a 5 year old battery.
 

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The logic I've heard with leaving it unplugged is that lithium-ion batteries like to be at 50% charge. The higher the charge, the more temperature sensitivity, and the lower the charge, the less temperature affects the cells. Lithium-ion batteries don't like to sit at 100% charge; it's why Tesla has an option to limit how much the battery recharges for days when you don't need the full battery capacity (such as your daily commute).

If you leave it plugged in all the time, yes, it will run the cooling system and such. It's just for long-term storage, the lithium-ion batteries will prefer to be at 50% SOC rather than the ~80% limit the Voltec powertrain keeps it at when "full".
True, but not applicable. The Voltec system in the Volt and ELR doesn't ever charge the battery to "full" the way the Tesla will. It's already always on that "limited recharge" state. The highest real state of charge a Voltec battery pack is at is in the high 80s percent, even when the meter has all the bars lit and says "Fully Charged", it's still not.
 
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