arnis
Posts: 751
Joined: Sat Jan 23, 2016 3:21 pm
Delivery Date: 23 Jul 2014
Leaf Number: 015896
Location: Estonia, Europe

Re: Replacement Battery with low cell Voltages

Mon Jan 09, 2017 12:28 pm

It just seems that way. From 3V to 2.6V there is hardly a percent of capacity difference.
It translates to 0,01V difference at top end. Aka same capacity difference (a percent).

If any cellpair drops below 2.5V it kills the contactor. Even during acceleration. This is why
power bubbles disappear a mile before dead.
Short range EVs <30kWh -- Medium range: 30-60kWh -- Long range: >60kWh
Charging: Trickle <3kW -- Normal 3-22kW -- Fast 50-100kW -- Supercharging >100kW

User avatar
Marktm
Gold Member
Posts: 359
Joined: Thu Jan 21, 2016 10:49 am
Delivery Date: 09 Jan 2016
Leaf Number: 022737

Re: Replacement Battery with low cell Voltages

Fri Jan 20, 2017 2:58 pm

Update - new battery has about 1200 miles on it and about 1-1/2 months. AH has dropped from 66.14 to 63. SOH dropped to 98%. Temp bars always mid-range, one QC, one "VLBW". At this rate, a I'll be back to my old batteries final reading of 43 AH in a little over a year.

I'd guess that as the pack balances better this will level off - but no sign yet.
2012 Leaf SL; 36,000 miles. Battery replaced November 1st, 2016.
Rural cabin with 6750 watts Grid tied PV. Off-grid solar Leaf charging capable (level II).

Cor
Posts: 158
Joined: Sun Jun 30, 2013 6:53 am
Delivery Date: 07 Jul 2015

Re: Replacement Battery with low cell Voltages

Thu Apr 20, 2017 5:45 pm

Marktm wrote:Update - new battery has about 1200 miles on it and about 1-1/2 months. AH has dropped from 66.14 to 63. SOH dropped to 98%. Temp bars always mid-range, one QC, one "VLBW". At this rate, a I'll be back to my old batteries final reading of 43 AH in a little over a year.
I'd guess that as the pack balances better this will level off - but no sign yet.

Mark,
Please note that the fabled 66.14Ah is just a magic number, not actual capacity of the battery, but rather something that gets programmed into the BMS as a starting point. Initial change can be fast, due to BMS learning the *real* capacity of the pack. Once that is found, degradation follows its normal course.
Cor.

User avatar
Marktm
Gold Member
Posts: 359
Joined: Thu Jan 21, 2016 10:49 am
Delivery Date: 09 Jan 2016
Leaf Number: 022737

Re: Replacement Battery with low cell Voltages

Thu Apr 20, 2017 8:35 pm

Yes, I've found that the AHrs and SOH has varied quite a bit since the new battery in place - went through a period of rapid drops and then would recover. I have a section of (10) cells that are about consistently 20 mv (after a full charge) below all the other cells. The lowest mv range I've seen is 24. I don't know if that is common, but makes me wonder if the original cells were not well selected or it just takes more time to "balance" properly.
2012 Leaf SL; 36,000 miles. Battery replaced November 1st, 2016.
Rural cabin with 6750 watts Grid tied PV. Off-grid solar Leaf charging capable (level II).

GerryAZ
Gold Member
Posts: 1481
Joined: Mon Nov 22, 2010 6:47 pm
Delivery Date: 12 Jun 2011
Location: Phoenix, AZ

Re: Replacement Battery with low cell Voltages

Thu Apr 20, 2017 10:02 pm

Try changing the shunt order to 8421 in Leaf Spy settings and see if it then shows the higher cells being shunted instead of the lower ones. I had 160 mV difference deep into VLBW last night and 16 mV difference at full charge this morning on my 2015 so I'm not too concerned to see 112 mV difference in your first screenshot. I suggest you drive and charge as you need and see if the cells balance better after more cycles.
Gerry
Silver LEAF 2011 SL rear ended (totaled) by in-attentive driver 1/4/2015 at 50,422 miles
Silver LEAF 2015 SL purchased 2/7/2015

SageBrush
Posts: 1483
Joined: Sun Mar 06, 2011 2:28 am
Delivery Date: 13 Feb 2017
Location: Colorado

Re: Replacement Battery with low cell Voltages

Fri Apr 21, 2017 1:19 am

@marktm,
You may find a thread from a few months ago informative that described a manufacturing defect in a new 2017 car. A couple cells were defective from the get go and IIRC voltage deltas over 200 mv easily logged. I don't think a MIL was ever set.

I agree with an earlier poster that Nissan is not going to care. You can keep logging for your own interest and ours, or just drive the car and hope for the best. My fingers are crossed that this sorts itself out, and that it is not a harbinger of what to expect in future replacement packs but Nissan's history leaves me antsy on your behalf.
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

User avatar
Marktm
Gold Member
Posts: 359
Joined: Thu Jan 21, 2016 10:49 am
Delivery Date: 09 Jan 2016
Leaf Number: 022737

Re: Replacement Battery with low cell Voltages

Sat May 06, 2017 11:16 am

Update on 11/3/16 battery replacement:
5/3/17:
64.76 ahrs
100.00 SOH
97.15 HX
386.07 VDC
222 GIDS
32539 miles (~2800 miles on new battery)

Appears things have settled down and "Lizard" is alive and well.
2012 Leaf SL; 36,000 miles. Battery replaced November 1st, 2016.
Rural cabin with 6750 watts Grid tied PV. Off-grid solar Leaf charging capable (level II).

Return to “Batteries & Charging”