edatoakrun wrote: johnlocke wrote:
edatoakrun wrote:...Why do those who have such serious anxiety regarding battery temperatures in passively manged packs keep buying LEAFs, and continue sharing their insecurities on this forum?
...I have a 22 mo. old car with 35,000 mi on it and only 73% of its original capacity!..
That is, IMO, extremely unlikely.
How did you determine the original
and present capacity?
Owners of "24 kWh" pack LEAFs are fortunate to have the one BEV for which multiple studies on battery capacity loss have been conducted.
You are claiming that your pack has lost a higher percentage of initial capacity in 35,000 miles, than did the four 2012 LEAFs tested over 50,000 miles, subject to brutally high temperatures (all packs averaging
over 100F for many months at a time) and the most punishing charge/discharge cycles.https://avt.inl.gov/sites/default/files ... et_EOT.pdf
Full report here:https://avt.inl.gov/sites/default/files ... ffects.pdf
It would have required a monumental effort on your part to reproduce those extreme conditions in your relatively moderate climate.
When you state:
johnlocke wrote:...I have a 22 mo. old car with 35,000 mi on it and only 73% of its original capacity!..
Do you really mean that is what your LBC says your capacity loss is?
And why do you want to believe
that Nissan builds a pack with that poor durability, but also that the LBC report is infallible?
My LEAF has a march 2011 build date, over 56,000 miles in a climate only slightly less warm than yours in Summer, and all indications from recharge capacity and range tests are that my pack has now lost close to 20% of its initial capacity (see my six-year-report quoted below) while my LBC now reports over 33.5% capacity loss (44.03 AHr and 66.46%).
...After more than six years, I've never run out of Wh, and never really suffered from "range anxiety" (charge-site anxiety yes, frequently) and largely credit my never relying on my LBC for its estimates of remaining energy capacity or battery capacity loss, for this experience.
Instead of relying on the LBC, I prefer to use only high-integrity data sources, primarily AVTA test results:https://avt.inl.gov/vehicle-button/2012-nissan-leaf
And parameters that can be measured accurately, kWh received from the grid, miles driven, and time.
Knowing the approximate nominal kWh available to LBW and VLB from my initial charge of "80%" or "100%", and watching the Nav screen m/kWh while I drive, I know both my nominal kWh used, and what are the approximate N kWh remaining wherever I drive, and can avoid all anxiety caused by the often "pessimistic" estimates from the LBC, of kWh remaining.
I also have a pretty good idea of what my LEAF's total and available battery capacity loss over time has been.
At six years and 52 k miles, my best estimates are:
My LEAF's pack had slightly under 19 kWh total capacity (as per AVTA test standards) and about 17 kWh available, when warm, at ~80 F.
That's about a 21% reduction from the 24 kWh Nissan specified, and ~18.5% lower than the average capacity Nissan actually delivered in 2012, according to AVTA testing of multiple LEAF packs...
If any of you are really anxious (or even only concerned
) about the "40 kWh" 2018 LEAF's "40 kWh" pack's passive thermal management, just don't buy one.
Unlike seven years ago when the LEAF was the only real
option, there are now several decent BEVs out there with complex thermal management systems.
But I doubt that will still be the case in a few more years, as the path to obsolescence for ATM is already fairly clear, IMO.
I haven't performed your test procedure but this is what I have done. I drive the same commute five days a week with only minor variations. The basic commute is 55 miles round trip. When new, the car used 51-55% of the capacity of the battery as measured by the Nissan % gauge on the dash. Currently it uses 70-75% of capacity. I am currently down 2 bars and expect to lose the third soon..
Just to do the math for you, assuming 28 KWH when new, I use between 14.3-15.5 KWH per trip. Currently then, the battery's max capacity is about 20.5 KWH or about 73% of original capacity. This agrees with reports from Nissan as to when the bars disappear. This also agrees with the readouts from Leafspy. When new, Leafspy reported 363 GID's or 28.13 KWH, it now reports 268 GID's or 21.03 KWH. I don't know about you but that seems pretty close to me.
As to my mild climate, I live in east San Diego County in the mountains at 2000 ft. My climate is closer to Phoenix then San Diego. The weather reports you see for San Diego are from the coast not inland. If you doubt my word, check Weather Underground station CAJAMUL8. That's my personal weather station.
By the way, I never use the guess-o-meter. I always use the percent charge screen. The last 12 miles of my day are always the same. Uphill with a 1500 foot elevation change. I wouldn't attempt it with less than a 30% charge and I'd prefer it to be over 40%. That's why I waited for a 30KWH battery in the first place. At this point I have to plan to DCFC somewhere if I have even a few extra errands to run. A 30KWH battery would suit me fine, it's just that now I seem to have a 20KWH instead.