evnow said:
...Let us look at it differently - how exactly would I use this new info from the lab ?
IMO, the first thing we can conclude, is that it is even more foolish now to try to establish a single “new” available kWh capacity value for a LEAF, than was the case before these results were available.
We already had a lot of evidence that capacity varies with recharge temperature, and the results from the three constant speed tests seem to indicate that even where the recharge temperatures are closely controlled, the recharge capacity the test LEAF’s LBC allowed appeared to have varied by at least ~3%.
The most important new information, IMO, is that I think we can now find the available capacity for the LEAF’s 100 mile EPA rating, and relate it to the constant speed and recharge capacity tests, which I think is very useful.
Since the UDDS (LA4) methodology was replicated in the baseline dynamometer test, resulting in 90.2 miles of range, and this testing criteria Is designed to be constant for available battery capacity, I believe we should be able to use the same ratio to determine ranges from the (close to) constant average kW use from the constant speed tests.
And since the 60 mph constant speed test (for example) resulted in 65.3 miles range, I believe we may tentatively conclude that a “new” 2011 (as defined by one allowing the same available battery capacity shown by the EPA 100 mile rating) should get ~72.4 miles, (+/_ at least ~3%, due to variable LBC operation) of range,
if you are able to accurately replicate all the test conditions.
That 72.4 mile range, BTW, looks to be well within the range that Nissan says it should be, if your trip computer actually accurately displayed the ~3.7 m/kWh that the 60 mph test did show.
http://mynissanleaf.com/wiki/index.php?title=File:NTB11-076a.jpg" onclick="window.open(this.href);return false;
And corresponds quite closely to the highway range performance Nissan promises, both on their website and in the sale/lease battery disclosure:
Highway driving in the summer: 112km (70 miles)
Speed: Average 88km/h (55 mph)
Temperature: 35 degrees Celsius (95 degrees Fahrenheit)
Climate control: On
Though we do not know exactly how much the lower speed and higher ambient and battery temperatures should increase the range, as opposed to the range decrease due to the AC use in this example.
http://www.nissan.ca/vehicles/ms/leaf/en/range-fundamentals.aspx#/range-fundamentals" onclick="window.open(this.href);return false;
So you could try to run your own constant speed range test, at any of the three test speeds, to assess your own battery capacity compared with 100 mile LA4.
Remember however, that neither a range test or a recharge test will determine your batteries level of “degradation”. They can only show you the level of battery capacity your LEAF is allowing you to access, out of the total capacity, as compared to that capacity level allowed the LEAFs the EPA used in it’s testing to get the 100 mile L4 rating.
And you may find attempting a constant-speed range test may not be the best use of your time and energy.
We have numerous examples on MNL of amateur attempts to get accurate constant-speed range test/capacity results, but failing, due to their inability to understand and adequately control all relevant test variables. If you want to give it a try, at least you now have an accurate reference test for comparison, and a 29 page checklist of methodology you can attempt to replicate, to the best of your ability. Good luck!
I believe you may find that you actually may be able to get more accurate (or at least less inaccurate) capacity results with your own L2 timed recharge tests, compared to the results published from LEAF 0356.
And probably more accurate than either, would be establishing your dash or nav screen m/kWh error rate, by using Carwings and replicating one of the m/kWh test conditions from 0356 over a practical test distance, to find the common error in your m/kWh displays and CarWings kWh use data, and so find the actual kWh use and available battery capacity of your LEAF.
madbrain said:
...The total stats for the day from Carwings are 80.8 miles driven, 20.9 kWh net consumption, 3.9 miles/kWh.
A brand new car with zero degradation is supposed to have 21 kWh usable...
You might want to go to the thread links I posted on Friday on page 3 for more suggestions on using your CW kWh use data.
