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I have around 26,000 EV miles over 26 months and haven't noticed a capacity loss yet. It may be because I almost always have it plugged in at home and work. Has anyone noticed any drop, and if so how many EV miles do you have?
The Volt is supposed to lose roughly 10-30% after about 9 years. I recall Tony Farrah, the main Volt engineer, saying that several times....

Thanks,
MrEnergyCzar
 

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I feel like I've lost 5 to 10 % capacity. Even though I'm only at 2.5 years, I've accumulated over 50k total and 40k EV. The warranty on the battery is 8yr 100k miles. I'll hit 100k in 5 yrs, so guess I'm on track for that 10 to 30%. I need to borrow my friends dash daq again to see where my SOC window is ranging.
 

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I am at 31k EV on my car (41k total). "Feels" like a loss of ~5% - 10% like @techtom. I used to have driving range of 41 miles in summer. Now runs more like 37-38. My best range used to hit 50 and this fall I could only get 46 on the same route with the same cruise control settings. Not exactly precise and scientific but I am on track to hit 100k in mid '16 and expect range will be down by around 20% by then.
 

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Guaranteed you've lost capacity. Argonne is testing the battery and so far the testing has shown a drop in capacity but not any drop in range or performance. As Henry says, the capacity loss isn't visible to the user.

Having a Leaf, I can tell you that lost range is very easy to detect. If you have to think about it then you probably have lost any.
 

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My car is now about 3 years old with 66,000 miles overall and 43,000 miles in EV driving. I haven't noticed any significant drop in range that I can attribute to the battery . My EVSE records indicate it still draws about the same 11.5 - 12.0 kWh at 240V to fully charge an empty battery. Back in September when it was warmer and I had my old original tires I was routinely getting 50+ miles of EV range.
 

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getting close to 40k miles. No noticeable loss of range. I fully charge the car 5 days/week (a 60 mile RT commute will do that).
 

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I'm at 40,000 EV miles over 24 months. I have only 139 gas miles. I actually have not used the CS mode in 1.5 years and have noticed absolutely no drop in range. I am trying to get the absolute most out of the Voltec warranty so I plan on having it still under warranty when I hit 99,500 EV miles.

About the widening of the SOC window, it was confirmed by I think WopOnTour that that does not happen.
 

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No loss here (26K). Even so, if G.M. were to cancel the Volt, I would consider ordering a replacement battery from the dealership (for use in the distant future).
 

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32k EV miles here. No detectable change to range or performance through 2 spring, summer, and fall seasons, and already had some extreme cold testing this fall. Same summer/winter ranges of 50+/42 (unless someone else drives:))

3 full seasons and 50k+ EV miles would be a better metric, so ask me again in a year and a half. Anyone at that point yet?

These testaments speak volumes for the value in a used Volt coming off lease...seen some going for as little as $17k! (Trade in value due to decal/paint issues)
 

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The Volt is supposed to lose roughly 10-30% after about 9 years. I recall Tony Farrah, the main Volt engineer, saying that several times....
I think you mean Volt Chief Engineer Andrew Farah.

I have 28,799 EV miles on my 2011 Volt and I haven't noticed any difference; if there is, I can't tell because mileage will vary for a number a reasons, including temperature, climate control usage and driving style. In the springtime I can get still 45 EV miles if I try. In the winter, EV miles can be in the low 20's, even if I try watching it - I usually don't and just drive it like a regular car with the automatic climate control on 73 / comfort / auto, which doesn't seem to affect the bottom end of range much. But it's been that way since the car was new, so I feel I can get my 16 years of battery life, living in Michigan where we don't get all the hot parking lot soaks, and the car is often garaged during the day.
 

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27,044 electric miles with no noticeable loss in mileage. I picked mine up on the last days of winter 2011 (March), so have been through three complete springs, summers and falls, and two complete winters.

The loss is not visible to the user, the car just widens the SOC window
About the widening of the SOC window, it was confirmed by I think WopOnTour that that does not happen.

I'm really curious which one of these statements is correct. I'm pretty sure that I had read that the SOC window does increase as the battery ages.
 

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Very reassuring, my 2012 Volt is appraching 17K miles with no noticeable loss of range and my 2013 is too new to worry about it.
 

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These testaments speak volumes for the value in a used Volt coming off lease...seen some going for as little as $17k! (Trade in value due to decal/paint issues)
They sure aren't going for 17k used at dealers, that's for sure. I did a search on cars.com, and the cheapest used volt within a 100 mile radius of me is a 2011 for 22k. I would actually consider swapping my other car for a used Volt if they were 17k....not 22k though.
 

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I'm really curious which one of these statements is correct. I'm pretty sure that I had read that the SOC window does increase as the battery ages.
I'm no professional electrical engineer, but my basic understanding of batteries, voltage, and SOC would indicate to me that there really is no need to expand any window.

That's because the software already shifts the window automatically, relative to the absolute amount of energy in the whole battery.

For example, with made up tech numbers (so don't nitpick the numbers), let's a say a brand new Volt's battery charges up the battery to 280 Volts, which is ~80% SOC, where as 100% charge let's say it's an even 300 Volts.

Then the software simply tracks a discharge of approx 10 kWh + 0 - before automatically triggering CS or "hybrid" mode. In the brand new battery, this equates to stopping at ~20% SOC.

Now let's say that some 50,000 EV miles later, the battery has degraded ~3%. Or in other words, if it could be fully charged, it would only make it to 290 Volts.

But the software doesn't care, it just charges up the battery until it reads 280 Volts, then discharges ~10kWh, rinse and repeat.

But in effect the window is shifting down (not widening) as the overall capacity lessens. This could be illustrated more clearly with a stacked bar chart.
 

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They sure aren't going for 17k used at dealers, that's for sure. I did a search on cars.com, and the cheapest used volt within a 100 mile radius of me is a 2011 for 22k. I would actually consider swapping my other car for a used Volt if they were 17k....not 22k though.
$17K used Volt was leased by a utility and they had decals on the side that probably causes some faded paint issues, so they were going to offer it at Kelly Blue Book trade-in price - but apparently had very low miles - a steal!
 

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... in effect the window is shifting down (not widening) as the overall capacity lessens. This could be illustrated more clearly with a stacked bar chart.
Thanks for the information! Would it be correct to say that the window is widening and shifting down? At new, with 16 Kwh capacity, using 10.5 Kwh would be a 'window' of 65.6% of total capacity (10.5/16). Let's say the total capacity drops to 14 Kwh, and the Volt is still using 10.5 Kwh, that means that the Volt is using 75% of the battery capacity (10.5/14).

This is how I understand the concept of 'widening the window' - using a larger percentage of the available battery capacity. For example, going from 65.6% of battery capacity up to 75% of battery capacity. Or am I just confused? :confused:
 

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so is the degradation purely on the miles and number of charges accumulated and not by any amount of years gone by? Also as it degrades let say it hits 30% degradation, will the green charge battery bar say show an equal percent NOT green once fully charged? Or does GM just move some of the spare capacity it does not allow us to use into that full charge bar observation so even though the battery is degrading they are giving up some of the spare compacity to show a full charge?
 

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This is how I understand the concept of 'widening the window' - using a larger percentage of the available battery capacity. For example, going from 65.6% of battery capacity up to 75% of battery capacity. Or am I just confused? :confused:
"Shifting down" if the stacked bar charts are different heights represent battery voltage, "widening" if they are the same height and represent % SOC (state of charge).

You say tomato, I say potato. ;)

But in either representation or way of looking at it, no sofware adapdation required, the middle "slice" is still simply a discharge of ~10kWh.

Again, just an edumacated guess, I'm not an expert.

Man I wish gm-volt had a bar chart feature. :)
 
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