Continuing from:
http://www.mynissanleaf.com/viewtopic.php?f=30&t=8802&start=6800" onclick="window.open(this.href);return false;
drees wrote:
Drained my car to turtle (5 GIDs) on a 80% charge (188 GIDs) driving 51.6 mi at 3.5 mi/kWh (About half surface streets, half freeway at ~70 mph). LBW came on a bit over 40 miles and VLBW came on around 48 miles. Pulled into garage with 12 GIDs and drained the rest using the heater/defroster on max. Turtle came on at 6 GIDs. Lowest cell-pair around 3.1V, average 3.3V, max 3.45V. Finishing battery temp around 90F, started the morning with the battery around 80F.
Charged to 80% immediately after that which took 4:18:35 drawing 16.157 kWh according to my Blink EVSE...
Not trying to cast doubt on the
reliability of any Blink device, but...
If you have 240 V, shouldn’t the EVSE pull ~16.55 kWh over that period of time?
Is your voltage lower than 240?
For that matter, anyone seen any variation from 16 A (L2) for a 2011-12 LEAF charger?
I've been wasting my time keeping time records, if it is not a constant.
drees wrote:
I didn't charge all the way to 100% as I wasn't planning on going anywhere soon this morning, but my last five 80-100% charges in the last 3 months ought to be good enough to take an average. Here they are in descending order from most recent to oldest:
1:08 3.567 kWh
1:00 3.268 kWh
1:04 3.116 kWh
1:10 3.683 kWh
1:00 3.300 kWh
Average time was 64 minutes, average energy 3.39 kWh.
So we can safely assume a full charge would have taken about 5h 22m and drawn 19.5 kWh.
We know that a new LEAF will pull about 24.5-25.0 kWh from the wall. Mine pulls less than 20 kWh.
In conclusion, my current Ah reading of 53.6 is 81% of a new LEAF's ~66 Ah. My energy used to charge is about 78-80% of what a new LEAF pulls from the wall to charge from turtle to 100%. If anything, the car is over-estimating capacity, not under.
Were all the “80%” to “100%” sessions at ~the same high battery temperatures?
IMO, due to the imprecision of LBC instrumentation, the exact percentage of total battery capacity when the LBC determines
every marked or set SOC (at least the ones I've seen, VLBW, LBW, "80%" and "100%") so the kWh accepted on any recharge between any two of these SOCs, as a percentage of total battery capacity, can probably vary significantly.
I believe this been shown, in my LEAF, by differences in both kWh charge accepted, and kWh discharge allowed, from VLBW to "100%" and back, even with near-identical battery temperatures when charging.
So I don't believe that you can reasonably expect to approximate capacity loss from any single charge session, or any single range test.
And trying to assemble a composite capacity with an average of previous sessions throws additional uncertainty into the question. You are, in effect, giving the LBC two chances to miscalculate the two charge-end SOCs, and while different LBC errors estimating "80%" and "100%" in two separate sessions could offset each other, they could also produce a higher cumulative error than you could get in a single charge event.
drees, I believe your LEAF has lost a significant amount of capacity, and mine has too.
As should be expected after ~3 years and ~27,000 miles.
I just think you are stretching to claim that your LBC's accuracy has been validated by what you have posted.
BTW, even if you can show that your:
drees wrote:
...own measurements of energy used to charge the car have directly correlated with the car's reported capacity loss...
The
part of your statement I found without support was:
drees wrote:
...own measurements of energy used to charge the car have directly correlated with the car's reported capacity loss and so has everyone else's...