camasleaf said:
edatoakrun said:
My first question whether is the 0.4 m/kWh variation between your cars dash and nav screens, as shown in the photos below, is normal for both your LEAFs.
My LEAF, both before and after the update, never has displayed a variation between those two m/kwh reports other than the nav screen always reading 0.0 to 0.2 higher m/kWh, on all longer trips in the normal (~3 to ~7 m/kwh) usage range, always conforming with the statement I quoted above.
AFAIK, all other LEAFs have reported the same. So, if both your LEAFs showed the 0.4 m/kWh variations between the dash and nav screen as shown below, the photos were taken ~simultaneously, and that is normal for both your LEAFs, I can't understand what is going on.
I am sorry I was not clear on that: the dash screen miles/kWh was never reset since we had the cars. Only the navigation screen miles/kwh was reset on Friday morning before the test (the dash trip miles was reset). It just happened that the difference between the life average and trip average is the same for both cars.
OK.
First, had you reset the dash m/kWh, I believe the 2012 would have displayed 4.3 m/kWh, as indicated by the 4.4 m/kWh nav screen, and the 4.3 m/kWh of both of the two individual trips reported by CarWings for that LEAF, exactly as my LEAF (and all other CarWings capable LEAFs?) would.
Both your LEAFs' nav screen m/kWh reports indicate that your 2011 got ~ 6% to 7% higher (4.4/4.7) m/kWh than your 2012 on this range test.
IMO, this result is very unlikely in a test with all known efficiency variables controlled. So, IMO, it is strongly indicative of error in one or both of the kWh reports used in that equation.
I suspect that your 2011 is responsible for most of this error, reporting nominal "kWh" that actually contain greater than 1,000 Wh content, on both its dash and nav screen m/kWh reports.
And your 2011 will report the same error,
but you will be able to discern its magnitude with much greater accuracy, after you have the NTB-11-041 update.
Your 2012 CarWings reports ~18.9 kWh between "100%" and ~VLBW (this would be more accurate if you had the day report or a single trip report, rather than adding up the two trips) which is very close to the ~18.7 kWh my LEAF reported at ~the same age and miles driven. Look what has happened to my CW use reports over the subsequent 18 months:
Below is how Carwings has reported the total energy use from "100%" to ~VLBW on my warm climate LEAF two years from the factory and with ~16,000 miles on the odometer.
While the reported kWh use has dropped quite a bit, My LEAF has displayed no significant loss of range from my first test, to most recent, on range tests of 95-113 miles, when corrected for all test variables, including speed, temperature both when charging and when driving, and my own driving efficiency (as reflected in the regen kWh reported by CarWings).
Of course my battery has lost capacity in the last 18 months, it just not yet a large enough loss to show up clearly in a range test, and is, IMO, nearly certainly far less than the kWh use results below, showing capacity loss approaching 15% just over the last 18 months (when adjusted for battery temperature) would indicate:
All charges prior to testing were to “80%", battery allowed to return to ambient temperature, and then charged @ 16 A 240 V to “100%”, two to three hours before range/capacity test begins, and then left plugged into the EVSE until departure.
IMO The distance driven at the point where the battery temp bars increased, when that has occurred, is useful data as to the relative battery temp and temperature the (temperature variable) battery capacity when the "100%" charge was completed.
9/7/11 18.7 kWh from "100%" to VLBW, 6 dash battery temp bars constant (as recalled later)
5/10 12 17.2 kWh, 5 to 6 temp bars ~mile 73
5/31/12 17.5 kWh, 5 to 6 temp bars ~mile 5
6/17/12 17.5 kWh, 6 temp bars constant
8/18/12 17.0 kWh, 6 temp bars constant
8/30/12 16.8 kWh, 6 temp bars constant
9/08/12 16.7 kWh, 5 to 6 temp bars ~ 4.6 miles
10/1/12 16.6 kWh, 6 temp bars constant
11/3/12 16.2 kwh, 4 to 5 temp bars ~mile 14
1/31 15.7 kWh, 4 to 5 temp bars ~mile 24
2/16/13 15.8 kWh, 4 to 5 temp bars ~mile 18
3/1/13 15.6 kWh, 4 to 5 temp bars ~mile 18
3/13/13 16.0 kWh, 5 bars temp constant
I think it is nearly certain, that the LEAF "gauge error" that has shown up in premature battery capacity bar loss and Wh/gid error in other LEAFs is also displaying itself in the dash and nav screen m/kWh, and also in the (more accurate) CarWings kWh use reports, from my LEAF, as I have posted above.
IMO, any LEAFer who can learn to use CarWings, may see the same sort of results I have, and also be able to largely differentiate any range loss due to real battery capacity loss, from their LEAF's questionable kWh use reports, as I believe I have been able to do.
http://www.mynissanleaf.com/viewtopic.php?f=31&t=11987&start=40" onclick="window.open(this.href);return false;
The problem of course, is that your 2011 was not updated, and so its CW kWh reports do not match its dash, nor the nav screen after applying the ~2.5% correction for the CW and dash odometer errors.
However, if you take what
probably would have been your nav screen m/kWh had you reset it) 4.6 and divide by the 5.6 indicated by CW, you get ~0.82, but with a large uncertainty, due to using the relatively inaccurate dash as your data source. Check your other CW reports for the 2011 against the dash, and I think they also probably will show that none of your other pre-update CW report numbers are "nonsense", they also seem to show the same constant error, though somewhat camouflaged by the inaccuracy from cycling it through the dash m/kWh.
Look at my comment from last fall:
Your earlier "nonsense" (pre-update Carwings) reports might not be so much so as you think.
IIRC, it always seemed to me that mine seemed like they might have read "off" by a constant coefficient, something close to 80%.
Unfortunately, I was "surprised" by the accuracy that came from the update, and never had a previous trip or trips logged accurately enough to compare to the (nearly) accurate (~2.5% miles driven error) post-update reports.
If you have trips or days of drives with all the m/kWh from dash/nav screen noted prior to the update, and repeat them now, you might figure out a way to recover data from the "nonsense".
Or maybe not...
http://www.mynissanleaf.com/viewtopic.php?f=30&t=9195&start=20" onclick="window.open(this.href);return false;
So, if you have the CW update done promptly on your 2011, and use the more accurate total kWh use report from CW for the same range of battery capacity, "100%" to ~ the same SOC at or beyond VLBW, you may be able to get a better estimate of what the kWh report error was, in your recent test.
The true moral of this story, IMO, is that it is not possible to get the most accurate estimate of your LEAF's kWh use report from any range test, and determine whether your dash, nav screen and CW may be reporting a common and significant error in these reports (as I think is likely in your 2011 LEAF, and almost certainly in my LEAF) unless you have CarWings capability.
And please reset the dash gauge at the start of the test, and either do the test in a single "trip", or alternately make no other trips on the same day (as I do) so you can get a single report of kWh use (and miles driven) from CarWings, rather than having to add up several "trips" with the kWh use reported with only 0.1 kWh resolution.
