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During my mini-roadtrip to PA this weekend, I took a photo of the energy display in the car (car charged fully to 100% prior to departing home).
I then updated my remotelink app to get a SOC% remaining figure.


43.1 kWh used / (1 - 0.31) = projected kWh used to full depletion = 62.5 kWh!

Now we know the kWh used estimator in the car is just that, an estimate. However, we've seen the Volt and Spark EV GOMs to be pretty accurate, so the Bolt's GOM should be just as accurate.

I did a computation earlier that day, and I got a 61.4 kWh used projection to 0%.

Seems that the usable capacity is definitely at least 60 kWh, that's for sure.
 

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Interesting. Sometimes fresh batteries "overperform" specs. IIRC this was the case with the Leaf. Might also be the case with the Bolt EV.

FYI I can't see your avatar or call up threads you've started from the Front Page. Any ideas on what that might be or is it just a problem I'm encountering?
 

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I collected about 125 data points using the same method in my Spark EV. The results varied by +5 and -8%. I was never able to isolate the cause. YMMV

 

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I collected about 125 data points using the same method in my Spark EV. The results varied by +5 and -8%. I was never able to isolate the cause. YMMV
Cool chart! Looking on line I see people saying the 2014 Spark has a 21kWh battery, other places it says the 2016 Spark has a 19kWh capacity! <edit> looking at wiki I see they changed battery supplier</edit> Did GM officially announce the capacity of the battery or did they just put out the EPA range data and car reviewers guessed at battery capacity based on range? Looks like with one month exception you had between 17.5KW and 18KW of usable capacity.

Keith
 

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Cool chart! Looking on line I see people saying the 2014 Spark has a 21kWh battery, other places it says the 2016 Spark has a 19kWh capacity... I doubt that GM made the battery smaller in the newer car! Did GM ever officially announce the capacity of the battery or did they just put out the EPA range data and car reviewers guessed at battery capacity based on range? Looks like with one month exception you had between 17.5KW and 18KW of usable capacity.

Keith
The 2014 Spark EV used a completely different battery than the 2015-2016 Spark EV. The 2014 used cells from A123 with a Lithium Iron Phosphate cathode chemistry whereas the 2015-2016 used cells from LG Chem that were similar to the 2nd generation Chevy Volt cells that used a blended Lithium Nickel Manganese Cobalt cathode chemistry. The total pack size did indeed go down from a bit over 21 kWh in 2014 to around 19 kWh in 2015-2016. GM has published battery size numbers but they have varied somewhat so the exact numbers are a bit unclear. GM press releases issued for the 2016 Spark EV say that the battery pack is 18.4 kWh.
 

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Yes, my understanding is that the LG cells allowed GM to use a smaller battery while maintaining the same usable capacity.
 

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I collected about 125 data points using the same method in my Spark EV. The results varied by +5 and -8%.
Nice chart. I think I'd use medians not averages. Even better might be to toss the two end points and then use the median. Just eyeballing it, that would flatten things a big but there would still be some variation, which might correlate to something like temperature (charging or operating).

Yes, my understanding is that the LG cells allowed GM to use a smaller battery while maintaining the same usable capacity.
I think they said same range. I doubt the capacities were the same. The A123 cells were beasts and could tolerate a lot of abuse.
 

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Interesting numbers bro1999. This is akin to car companies saying the gas tank holds 20 gal, but you can only use 17... Maybe the bolt has a use able KWH of 60, but the pack is actually bigger? Really all I care about is how much can I use vs. how big it is. If the the 1st Gen Volt was allowed to use more KWH out of the pack, we would have seen a higher rated EV range from the beginning. Of course, we don't know how that would have affected battery life.
 

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Too large a margin for error without multiple data points, I would think.

However, you can reasonably say it is 60+ usable as opposed to volt "16-18.4" which is really 10-14.
 
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