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Lets say a Volt stays in dealer lot for couple of years in Alaska, is it possible for the traction battery to be completely dead and how can be started if there is no 110v available. This case will be even worst for prius with the smaller battery and no charging option.
 

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Is it possible? I suppose anything is possible. However it is highly unlikely. Some Volts have sat on dealer lots for months (in some cases in certain parts years) and they will still start up and run just fine.

GM has done a good job protecting the HV battery. The 12V battery might die but the HV battery will do just fine. Keep in mind even when the EV range is zero there is still ~30% charge in the battery.
 

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I haven't heard on the Volt. However, with Toyota hybrids this is certainly possible and does happen. Most Toyota dealerships have a special charger that is for the high voltage battery. The trouble is.. If the car sits long enough for it to discharge that far, there's a limit time period that it can be rescued. If it stays in a discharged state too long, it will never charge back up.
 

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I have a 2012 Volt battery I play with that was taken from a wreck in 2013.

It still has lots of voltage, average of 3.83v per cell last I checked. IIRC, it was 3.88v when I bought it.

When the car is parked, the traction battery is disconnected, IIRC. Only the 12vdc battery in the hatch area is active. That battery does die if parked, and should be replaced if the car was sitting. ie - If a 2014-2015 is for sale, they should replace that battery.

EDIT - Note that when a Volt battery is "0 miles left" it's not drained. There is still a huge buffer zone at the bottom. It's how a Volt can produce full HP when the battery is drained. The gas engine is too small to produce full power without electric assist.
 

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New Li-Ion chemistry has a great "shelf-life" as the battery is only active in a live circuit (flowing currect), much differently than the common chemical cells (AA,C, and D) and the lead-acid cell in the 12VDC battery of all automobiles which continue to degrade and use their materials even when the cells are in storage. I found a small Li-Ion "bag" cell that was unused for five years, yet it still had 2.9 VDC, and took a recharge up to 3.9 VDC with no problem.

So a Volt or any Li-Ion EV will have a longer "shelf-life" or survive years of unuse and no charge with little or no degradation. But if there is some active circuit, the battery can discharge, until the protection circuits kick in and disconnect the pack. Then it can still survive more years unused. They can outlast the life of the car or the owner!
 

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I haven't heard on the Volt. However, with Toyota hybrids this is certainly possible and does happen. Most Toyota dealerships have a special charger that is for the high voltage battery. The trouble is.. If the car sits long enough for it to discharge that far, there's a limit time period that it can be rescued. If it stays in a discharged state too long, it will never charge back up.
That may be for the original Nickel-Cadmium (Ni-Cad) cells that will degrade over time, and also suffer a "charge memory" if not conditioned correctly. My dentist has a 2007 Prius and he has already swapped the batteyr pack in it. Newer Prius models should be already using Li-Ion cells, and that battery should be as reliable as for the Volt. I say this because of the Li-Ion cells, not for Toyota's quality which still is bad.
 

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When the car is parked, the traction battery is disconnected, IIRC. Only the 12vdc battery in the hatch area is active. That battery does die if parked
I thought from 2013 and on the 12V battery is charged off the main traction battery? So as long as the main battery has juice the 12V battery will always be charged.
 

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I thought from 2013 and on the 12V battery is charged off the main traction battery? So as long as the main battery has juice the 12V battery will always be charged.
That is if it is plugged in. It will periodically check the 12 volt battery and trickle charge it if necessary.
 

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However, with Toyota hybrids this (the high voltage battery going dead) is certainly possible and does happen. Most Toyota dealerships have a special charger that is for the high voltage battery...
The Toyota Prius uses a Nickle Metal Hydride battery which has a much higher self discharge rate than Lithium batteries like the Chevy Volt uses. And, I believe, the Prius discharges its battery more than does the Volt, due to the different capabilities of the batteries.
 

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The only real problem is IF you got the Li-ion battery to drain to 0% it will probably brick. Lithiums do NOT like going to zero. It's why cellphones, laptops and even the volt cut you off at 10-20% SOC. So there's a buffer that keeps you out of brick territory.

The lead acid/AGM battery by then would definitely be sulfated and dead beyond the point of no return unless it was on a tender.
 

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The volt cells do not have any noticeable real world self discharge.
We're talking parked for years and years on end to get to actual 0.

The most self discharge is when cells are fully charged (they're basically "overcharged" to get that max rate) - it bleeds out quickly after charge completion and settles at a lower voltage.
Volt batteries are never charged this high, so experience very low self discharge rates.
Worst case, with a "dead" battery @ 20% and parked for 2-3 years without topping off, you'd probably still be above 0%.

12V battery will most certainly be damaged by then, though.
 

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I hear the Tesla Roadster, even with LiIon, was another story. Earlier models had a bad scenario where the battery could fully discharge and damage itself to the tune of an out of warranty full battery replacement. Agree, normally LiIon has great shelf life, and with low voltage cut off, can be very reliable.
 

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I hear the Tesla Roadster, even with LiIon, was another story. Earlier models had a bad scenario where the battery could fully discharge and damage itself to the tune of an out of warranty full battery replacement. Agree, normally LiIon has great shelf life, and with low voltage cut off, can be very reliable.
Well first Tesla uses a different Li-Ion battery chemistry than GM that is slightly more prone to self discharge but that's not the main reason. Tesla has always had some difficulties with Vampire draw. The cars systems even when off draw some power from the HV battery. They have greatly improved but still have a noticeable vampire draw. GM has a physical disconnect on the HV battery when the car is turned off and not plugged in.
 
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