drees said:
...The NREL advanced vehicle testing typically gives a full report of motor/vehicle efficiency at some point in time (look at the Sonata hybrid data in the first PDF). I couldn't find any such report yet, so hopefully they publish additional information at some point in time.
Of course
the full report was presented the day after you wrote that drees, and is available here:
http://www.transportation.anl.gov/D3/data/2012_nissan_leaf/AVTALeaftestinganalysis_Major%20summary101212.pdf" onclick="window.open(this.href);return false;
Unfortunately, it doesn't seem many of those commenting on LEAF battery capacity and range, or maintaining the Wiki, have full comprehension of it.
And since widespread misconceptions RE the LEAFs battery capacity and range seem to have originated in this thread, maybe the actual report should be discussed here.
The wiki repeats the misnomer of this thread, that the "Benchmarking of Competitive Technologies" data is:
...Further confirmation of the range of a new Leaf comes from a teardown of a Leaf by the NREL which revealed usable energy of a new Leaf at 21.381 kWh...
http://www.mynissanleaf.com/wiki/index.php?title=Battery_Capacity_Loss" onclick="window.open(this.href);return false;
Which also misstates that the two sources on the first page of this thread:
http://www1.eere.energy.gov/vehiclesandfuels/pdfs/merit_review_2012/adv_power_electronics/ape006_burress_2012_p.pdf" onclick="window.open(this.href);return false;
http://www1.eere.energy.gov/vehiclesandfuels/pdfs/merit_review_2012/veh_sys_sim/vss030_lohsebusch_2012_o.pdf" onclick="window.open(this.href);return false;
Were reports of "NREL LEAF Teardown and Detailed Testing".
Which they clearly are not.
The "Leaf Recharge System Efficiencies Defined" diagram on page nine of the link closest above does not identify the condition, temperature, or actual battery capacity at the time the available battery capacity 21.381 kWh was found.
In contrast,
the actual report states
available battery capacity on p. 21:
Advanced Powertrain Research Facility
AVTA Nissan Leaf testing and analysis
Measurement point Average value
A) Wall Plug energy 21.722 AC kWh
C) DC energy to pack 18.529 DC kWh
E) DC Test energy * 17.957 DC kWh
Analysis Note:
Values are based on
13 level 2 battery
charge events from
completely depleted
to fully charged...
Obviously, the averages above cannot be for "new" batteries, as they are for multiple charge/discharge events. They also could be for LEAFs with packs that have already suffered significant total capacity loss, but I don't see any indications in the report that that is the case.
Multiple charge/discharge cycles are necessary to give an accurate picture of available battery capacity, given the LBC's well documented use of inconsistent percentages of the total battery capacity, either due to instrument error, or by design, as suggested by the reference on p.17 of the report to:
...Two different Leafs, two different voltage cutoffs
which could contribute to the battery
capacity difference...
IMO, the inference from the rest of the report is that the battery testing might have been conducted at widely ranging temperatures, from 20 F to 95 F, which could explain the relatively low average available battery capacity of 17.957 kWh.
Unfortunately, the battery temperature (and other test conditions) for the
merit review 21.381 kWh available capacity which started off this thread, have (AFAIK) never been reported.
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Are you suggesting that the range test in Arizona, which used the figure of 21 kwh available energy from the battery (leading to a range of 84 miles for a new Leaf) was CORRECT??? Absolutely shocked! Who could have guessed that the guys who obsessed and argued about, tested extensively, etc. would be more accurate than the armchair quarterbacks penning articles for the internet??? Looks like vindication to me.
