jbuntz said:
Currently my stats are 50.44 Ah 63.46 SOH 60.59 Hx 21622 Odo 230Gid 4 bars down. Appmt for Tuesday to get tested for replacement.
I did a test yesterday drove 77 miles to 6 GIDs. 70 miles were at 70 mph and the rest at less than 30. LeafSpy reported 17660 Wh used .5kWh remains...
You're on the right track, but first thing, throw out all the LBC ("LeafSpy reported") data.
jbuntz said:
I then charged to 100%. EVSE total input was 25 kWh. Input was at 6737 Watts...
At 90% charger efficiency that would add about 22.5 kWh...
But It is unlikely your discharge/recharge efficiency was anywhere near 90%.
Nissan's EPA submission for your pack reports:
Recharge Event Energy (kiloWatt-hours) 31.7807
https://iaspub.epa.gov/otaqpub/display_file.jsp?docid=36671&flag=1
Which is consistent with a ~30 kWh total pack, with 90% (27 kWh) available, and discharge/recharge efficiency of 85%.
jbuntz said:
I also noticed that the car displayed 3.5 mi/kWh avg...
First, use mapping software to find your odometer error in your CW/NC
miles driven reports to correct the
mi in
3.5 mi/kWh.
Funny but carwings is reporting zeros for the 17th....
Then, use your expected discharge/recharge efficiency to correct the
kWh used error, as reported by CW/NC in
3.5 mi/kWh.
If your 30 "kWh" LEAF has the same error in kWH use reported on the Dash/NaV screen and CW/NC as do 2011 LEAFs, then you could calculate capacity loss from this
consistent error, without having to do full discharge/charge tests.
My 2011's LBC currently reports ~36% capacity loss, but the kWh use report error is close to a consistent 12%, meaning each nominal kWH reported on my dash/nav screen and CW/NC, actually contains ~1,120 WH, and my available pack capacity is now ~24 % below spec.
However, the
3.5 mi/kWh. you report (you're sure that was for the entire 77 miles, and only those miles? From the from dash or Nav screen?) suggests the kWh used, as reported by CW/NC was about 22 kWh (77/3.5) ~88% of the 25 kWh accepted on the recharge, close to the expected expected discharge/recharge efficiency and not nearly the ~20% error (see below) that seems to be shown by your 25 kWh recharge report.
jbuntz said:
So what do you think the true capacity is and what are they going to tell me Tuesday?
I have no idea what Nissan will tell you, but since your pack apparently accepted almost 79% of its specified capacity (25/31.7807) after a less-than-complete discharge, I think with further observation you would probably find that your pack still has between 75% and 85% of its specified capacity, as opposed to the ~63% your LBC is reporting.
One big problem is my power meter only reads whole kWh so it could have been 24.6 - 25.5 so 77-80% of rated capacity.
The big variable you did not mention is battery temperatures during the previous charge, the discharge, and the recharge. The warmer the pack, the higher the available capacity,
and also the higher the efficiency of the charge and discharge cycles.
The battery was at ~105F at the end of the trip.
Unfortunately (and unlike for the "24 kWh" packs) we have virtually no temperature data reported for the "30 kWH" packs.