Gorge
Posts: 34
Joined: Tue May 31, 2016 7:37 pm
Delivery Date: 01 Jun 2016
Location: Los Angeles, CA

Re: SOH not Dropping compared to AHr?

Fri Dec 09, 2016 1:52 pm

Odd. I just checked LS. AHr at 45.257 and still sitting at 72% SOH. I should hit 41-42 AHr by the end of warranty, but I wonder if my SOH will ever drop.

LeafMuranoDriver
Posts: 325
Joined: Wed May 13, 2015 8:15 am
Delivery Date: 01 May 2015
Leaf Number: 323189
Location: Los Angeles, CA

Re: SOH not Dropping compared to AHr?

Fri Dec 09, 2016 3:02 pm

DaveinOlyWA wrote:well high SOH is always good and your low usage is probably contributing to the lower numbers but I don't think I have ever seen an ahr bounce around like yours. Since I work on the road, my LEAFing varies from 100 to 600 miles a week so pretty extreme so I also see my numbers bounce around but nothing compared to yours. I mean 4-5 ahr is waaaay beyond what I see!

Agreed. The swings can be quite big. All comes down to driving/charging.

I have not seen any other car with similar stats that has anything more than 92-95% SOH. Definitely unique.
2015 Leaf S w/ QC
Mfg: Jan. '15 // Pur: May '15
Best: 6/27/15 - 1,416 Miles - 292 GIDs - 63.11 Ahr - 22.6 kWh - 100% SOH - 97.2% Hx - 4 QC, 29 L2
Worst: 12/12/15 - 4,616 Miles - 259 GIDs - 55.02 Ahr - 20.1 kWh - 99% SOH - 82.8% Hx - 17 QC, 96 L2

Gorge
Posts: 34
Joined: Tue May 31, 2016 7:37 pm
Delivery Date: 01 Jun 2016
Location: Los Angeles, CA

Re: SOH not Dropping compared to AHr?

Thu Feb 16, 2017 11:43 am

Is there any back of the napkin calculation on the correspondence between AHr and SOH?

I've dropped almost 3 AHr (below 45 AHRr now) over the past 9 months and I'm still stuck at 72% SOH per LSP. Getting frustated at the lack of change. I see people with 42-43 AHr and 62-65% SOH. Not sure how I can drop another 4 AHr and see a 7-10% SOH decrease.

SageBrush
Posts: 1247
Joined: Sun Mar 06, 2011 2:28 am
Delivery Date: 13 Feb 2017
Location: Colorado

Re: SOH not Dropping compared to AHr?

Thu Feb 16, 2017 1:31 pm

Dave,
How would you go about trying to charge/rehab weak cell(s) in a LEAF ?

I think you are saying repeat cycles of discharge to level of weakest cell followed by charge to 100%

Is this right ?
2013 Model 'S' with QC & rear-view camera
Bought off-lease Jan 2017 from N. California with 63.9 Ahr after 22k miles
Car is now enjoying an easy life in Colorado

DaveinOlyWA
Gold Member
Posts: 12116
Joined: Sat Apr 24, 2010 7:43 pm
Delivery Date: 10 Nov 2016
Leaf Number: 314199
Location: Olympia, WA
Contact: Website

Re: SOH not Dropping compared to AHr?

Sat Feb 18, 2017 8:04 am

SageBrush wrote:Dave,
How would you go about trying to charge/rehab weak cell(s) in a LEAF ?

I think you are saying repeat cycles of discharge to level of weakest cell followed by charge to 100%

Is this right ?


Can't really discharge to the level of the lowest cell because weaker cells will discharge quicker.

I am not a fan of discharging car to very low levels but had to because of my needs. So I found that yeah, getting to single digit GIDs and recharging to full on L2 created a very well balanced pack for me.

To add; my S30 has only been below 10 GIDs 4-5 times so far and part of that is NCTC which encourages me to not cut it close. I tend to now just stop. Summer driving is always more extreme so we shall see but so far, my S30 is not nearly as balanced as my previous 24 kwh packs were and the depth of cycling is the biggest process change.

Really too early to make any conclusions
2011 SL; 44,598 miles. 2013 S; 44,840 miles.2016 S30 (build 10/2016)"low water marks" 24,858.2 miles.363 GIDAhr 80.66Hx95.95%kwh28.1QCs215,L2's 227
My Blog; http://daveinolywa.blogspot.com" onclick="window.open(this.href);return false;

DaveinOlyWA
Gold Member
Posts: 12116
Joined: Sat Apr 24, 2010 7:43 pm
Delivery Date: 10 Nov 2016
Leaf Number: 314199
Location: Olympia, WA
Contact: Website

Re: SOH not Dropping compared to AHr?

Sat Feb 18, 2017 8:19 am

Gorge wrote:Is there any back of the napkin calculation on the correspondence between AHr and SOH?

I've dropped almost 3 AHr (below 45 AHRr now) over the past 9 months and I'm still stuck at 72% SOH per LSP. Getting frustated at the lack of change. I see people with 42-43 AHr and 62-65% SOH. Not sure how I can drop another 4 AHr and see a 7-10% SOH decrease.


because ahr is a measure of charge capacity, your drop could simply be an indication of a "healthier" battery that is simply way out of balance.
2011 SL; 44,598 miles. 2013 S; 44,840 miles.2016 S30 (build 10/2016)"low water marks" 24,858.2 miles.363 GIDAhr 80.66Hx95.95%kwh28.1QCs215,L2's 227
My Blog; http://daveinolywa.blogspot.com" onclick="window.open(this.href);return false;

SageBrush
Posts: 1247
Joined: Sun Mar 06, 2011 2:28 am
Delivery Date: 13 Feb 2017
Location: Colorado

Re: SOH not Dropping compared to AHr?

Sat Feb 18, 2017 10:42 am

I have no idea what SOH and Hx measure, other than it is nice to see them high :-)
When they do not correlate with remaining Ahr at full charge questions come up but I've only seen guesses as to why.

I do agree with Dave that cell that are unbalanced may be one possible answer and should be remediated if possible with charges up to 100% SOC. This is all black magic, and Nissan is not going out of its way to dispel the mystery.
2013 Model 'S' with QC & rear-view camera
Bought off-lease Jan 2017 from N. California with 63.9 Ahr after 22k miles
Car is now enjoying an easy life in Colorado

Gorge
Posts: 34
Joined: Tue May 31, 2016 7:37 pm
Delivery Date: 01 Jun 2016
Location: Los Angeles, CA

Re: SOH not Dropping compared to AHr?

Sat Feb 18, 2017 9:25 pm

SageBrush wrote:I have no idea what SOH and Hx measure, other than it is nice to see them high :-)
When they do not correlate with remaining Ahr at full charge questions come up but I've only seen guesses as to why.

I do agree with Dave that cell that are unbalanced may be one possible answer and should be remediated if possible with charges up to 100% SOC. This is all black magic, and Nissan is not going out of its way to dispel the mystery.

I charge to 100% every night so I would think it should be calibrated.. but who knows.

oleviking
Posts: 37
Joined: Fri Oct 14, 2016 6:35 am
Delivery Date: 21 Oct 2016
Leaf Number: 301969
Location: Orlando, FL

Re: SOH not Dropping compared to AHr?

Sun Feb 19, 2017 4:39 am

My SOH has shown 83% since the day i leased the 2016 SV, don't know what to think about that, only 3,000 miles on it as of today.

gregn
Posts: 81
Joined: Wed Apr 06, 2016 8:29 pm
Delivery Date: 06 Apr 2016
Leaf Number: 308289
Location: Montpelier, VT

Re: SOH not Dropping compared to AHr?

Mon Feb 20, 2017 4:23 pm

oleviking wrote:My SOH has shown 83% since the day i leased the 2016 SV, don't know what to think about that, only 3,000 miles on it as of today.


See below in the signature my stats on 2016 Leaf SV. Mine went up when I ran it hard a few times. Long trip 6 QC sessions in one day. After each time the SOH went up and stayed. I have 17 k on the car since April. It seems to like to drive. My range has improved it seems as well. I noticed the pack balance seems to have a lot to do with that.
See if you can drive the car more.
2016 Leaf SV Pearl Blue
67 mile daily commute
Bat Stats@15%SOC: AHr=78.23 SOH=98% Hx=93.13% Balance Delta = 15mv
odo=16,820

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