DaveinOlyWA
Gold Member
Posts: 12085
Joined: Sat Apr 24, 2010 7:43 pm
Delivery Date: 10 Nov 2016
Leaf Number: 314199
Location: Olympia, WA
Contact: Website

Re: Dramatic Ahr rise after quick charge?

Fri Sep 22, 2017 4:31 pm

I know this will seem counterintuitive especially in light of what you are seeing but some realities;

Known Degradation Mechanisms

Time
Cycling
Heat
extended periods of time at extreme High/Low SOC

So those are your tools.

sounds like time is the least convenient and in light of Nissan's new battery exchange policy for out of warranty packs, could be your downfall

So Heat is one thing. you only need to QC a lot. Like 5 times in a day. That will take a lot of driving but I am guessing the cycling/miles you have plenty of...

So despite what appears to be happening when you QC, its not. Your pack still must be tested for degradation no matter what the car says. I can only remember one for sure, maybe a few more that had lost their bars, took it in and failed the degradation test. (they did pass the test a short time later) There are other cases when the last bar disappeared only to reappear a few days later. rarer, but not unheard of.
2011 SL; 44,598 miles. 2013 S; 44,840 miles.2016 S30 (build 10/2016)"low water marks" 24,261.3 miles.363 GIDAhr 80.66Hx95.95%kwh28.1QCs205,L2's 226
My Blog; http://daveinolywa.blogspot.com" onclick="window.open(this.href);return false;

sandeen
Posts: 113
Joined: Fri May 12, 2017 1:45 pm
Leaf Number: 026685
Location: Minnesota

Re: Dramatic Ahr rise after quick charge?

Fri Sep 22, 2017 7:06 pm

One other factor that I had read is "time spent under charge" - the idea that the chemical reactions happening while the car is charging are also responsible for deterioration, and the longer time under charge, the more degradation occurrs. Unfortunately I'm not finding that reference now. I understand that there are many factors involved, though, sure - and that heat seems to be near #1.

It got unseasonably warm here today, 94F, with 88 and 87 for predicted the next two days. I'm at 43.45Ahr today after dropping another 0.08; nearly 7% of reported 2011/2012 4-bar losers lost their bar at 43.45Ahr or above. We'll see what the next couple days bring. At this point I'm not willing to risk the DCQC "bump" but when the weather gets colder, if things stabilize or start going in the wrong direction, I'll hit the quick charger and roll the dice if I have to, probably with enough time for the effect to fade, if it will fade.

If only I lived in Arizona. ;)
2012 SL from TX, (mfg 8/12), used, dropped to 8 bars at 43.50 Ahr, 40,601 miles. my daily stats =/= my collected data on 4-bar losers

sandeen
Posts: 113
Joined: Fri May 12, 2017 1:45 pm
Leaf Number: 026685
Location: Minnesota

Re: Dramatic Ahr rise after quick charge?

Fri Sep 22, 2017 7:08 pm

Actually, time may be #1. If I take my best fit line and extrapolate back to the date of manufacture, it's darned near 66Ahr. As if its' been declining at a near-constant rate ever since it was built. :)
2012 SL from TX, (mfg 8/12), used, dropped to 8 bars at 43.50 Ahr, 40,601 miles. my daily stats =/= my collected data on 4-bar losers

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