DaveinOlyWA
Well-known member
DougWantsALeaf said:Ok,
Here is my latest thought on the quarterly adjustments. Safe Harbor warning, no science or methodology sits behinds this hypothesis.
My guess is that Nissan is quarterly tuning the amount of buffer, and with it bringing down the SoH reported to reduce the speed of degradation of the battery. In doing so, the battery post tuning is under reporting true remaining SoH. Then as the battery ages, if the battery underneath stays flatter, it can give back a little of the capacity in line with their internal model. In this way, it can help de-risk its potential battery replacements (under the 8 year / 70% warranty...same as Tesla) as well as help consumers maintain the best battery possible given their usage habits. Almost like how Tesla will throttle back supercharing on cars if its done too much to protect the brand, this is Nissan's way of doing it.
All anecdotal. We are coming up on the 1 year anniversary of our car, and it is doing well. Battery is at 95.67% and I should know in a few days if that is pre or post the last adjustment.
I am thinking the same but the real question becomes what actions cause the adjustment to be more favorable?
I just had my 2nd adjustment on the Plus but had several on the 40 kwh pack and no real conclusions presented here, only observations.
My biggest adjustments came with lighter driving needs including 4 times when charging was more than ¾ DC but only charging 2-3 times a week. This was same for both packs.
Smaller adjustments happens when I drove more.
Increases happened when I drove the most and DC'd a lot frequently 2-3 times in a day. BUT this was a mix as I had one go up, one was a medium down and two adjustments simply didn't happen.
So on my Plus;
First 90 days, relatively light driving (got car mid Nov) nearly all DC charging (did plug into Volta a few hours every time I went to see a movie so maybe 8-10 of those sessions) but the rest was DC (still had NCTC) and those sessions only happened 2-3 times a week. Pack temps spent most of their time in 40's and 50's. A 30-40 minute charge session at 120-124 amps (no knee) would yield temps that sometimes hit the mid 70's.
But that gentleness yielded my largest ever adjustment; 4.15 ahr drop, 2.45% SOH.
2nd 90 days; Pretty much same as above with less movies (obviously) and a lot more driving in last 30 days with DC events bumping to 4 or 5 times per week (one a day for 4 day workweek and occasionally once during 3 day weekend)
Adjustment was "high normal" losing 2.38 ahr, 1.29% SOH.
In the current quarter; I will be doing mostly AC charging at home with target SOC of 75% (I actually hit 76% 3 days in a row...)
I am hoping the pattern holds up after my current work project ends (which is accounting for all the extra driving) the assignments are offered weekly so no real idea how long they will continue but based on our Governor's latest announcements of a tiered "back to the new normal" life, I am guessing at least another 2-4 weeks?
So we shall see.