henrydehoja
Posts: 83
Joined: Sun Sep 16, 2018 6:40 pm
Delivery Date: 12 Sep 2018
Leaf Number: 317129
Location: Metro Boston, MA

Re: Key-off battery drain

Fri Jan 31, 2020 10:55 am

GerryAZ wrote:
Wed Jan 29, 2020 10:01 pm
That is much more loss of charge than I typically have. Did you leave something plugged in to the OBDII port? I typically see either the same SOC or 1% to 3% loss of charge when I return to the car after as much as a month.
Is that what you see on your 2019 model?
2018 Nissan Leaf S w/QC
Placed in action: 9/2018

henrydehoja
Posts: 83
Joined: Sun Sep 16, 2018 6:40 pm
Delivery Date: 12 Sep 2018
Leaf Number: 317129
Location: Metro Boston, MA

Re: Key-off battery drain

Fri Jan 31, 2020 10:55 am

Nubo wrote:
Thu Jan 30, 2020 11:27 am
GerryAZ wrote:
Wed Jan 29, 2020 10:01 pm
...I typically see either the same SOC or 1% to 3% loss of charge when I return to the car after as much as a month.
This is my experience as well.
Is that what you see on your 2018/2019 model?
2018 Nissan Leaf S w/QC
Placed in action: 9/2018

User avatar
Nubo
Posts: 5728
Joined: Fri May 28, 2010 11:01 am
Delivery Date: 31 Oct 2014
Location: Vallejo, CA

Re: Key-off battery drain

Fri Jan 31, 2020 11:18 am

henrydehoja wrote:
Fri Jan 31, 2020 10:55 am
Nubo wrote:
Thu Jan 30, 2020 11:27 am
GerryAZ wrote:
Wed Jan 29, 2020 10:01 pm
...I typically see either the same SOC or 1% to 3% loss of charge when I return to the car after as much as a month.
This is my experience as well.
Is that what you see on your 2018/2019 model?
No, with a 2012 and 2015.
I noticed you're still working with polymers.

lorenfb
Posts: 2464
Joined: Tue Dec 17, 2013 10:53 pm
Delivery Date: 22 Nov 2013
Leaf Number: 416635
Location: SoCal

Re: Key-off battery drain

Fri Jan 31, 2020 9:07 pm

For those that are interested in the energy consumed by a 50ma standby current drain on the 12 volt battery over one month:

Energy (12V battery) = .05 amps X 12V X 24 hrs X 30 days = 432 Whrs = .43 kWhrs

Assuming 80% conversion efficiency on the converter, the load energy loss on the main battery is about .5 kWhrs.
For a 24 kWh battery in one month, that's about 2% loss.
#1 Leaf SL MY 9/13: 76K miles, 47 Ahrs, 5.0 miles/kWh (average), Hx=70, SOH=73, L2 - 100% > 1000, temp < 95F, (DOD) > 20 Ahrs
#2 Leaf SL MY 12/18: 10.3K miles, SOH 109Ahrs/115Ahrs, 5.2 miles/kWh (average), DOD > 20%, temp < 105F

nlspace
Posts: 204
Joined: Mon Jun 05, 2017 10:21 pm
Delivery Date: 06 Jun 2017

Re: Key-off battery drain

Fri Jan 31, 2020 9:58 pm

@ Henry,

i would guess that your USB chargger has an internal power supply that is always ON, even if nothing is plugged on the cable, and that accounts for your higher drop in SOC. The 12V aux battery was being drained at higher than nominal, and the DC-DC was operating more frequently and using energy from the pack.

+1 on the good analysis by loren

LeftieBiker
Moderator
Posts: 15296
Joined: Wed May 22, 2013 3:17 am
Delivery Date: 30 Apr 2018
Location: Upstate New York, US

Re: Key-off battery drain

Fri Jan 31, 2020 10:06 pm

It's also becoming clear that the 2018+ Leaf is only slightly better at keeping the 12 volt battery charged, so if the car "forgets" to top it off with a phantom drain, or if the period between top-offs is too long to compensate for the drain, the 12 volt battery has less reserve capacity available to keep everything working properly. IOW you're almost as likely to see a 12 volt battery failure as you are with earlier Leafs.
Scarlet Ember 2018 Leaf SL W/ Pro Pilot
2009 Vectrix VX-1 W/18 Leaf modules, & 3 EZIP E-bicycles.
BAFX OBDII Dongle
PLEASE don't PM me with Leaf questions. Just post in the topic that seems most appropriate.

henrydehoja
Posts: 83
Joined: Sun Sep 16, 2018 6:40 pm
Delivery Date: 12 Sep 2018
Leaf Number: 317129
Location: Metro Boston, MA

Re: Key-off battery drain

Sat Feb 01, 2020 4:32 pm

As mentioned, it looks like the USB charger (Aukey CC-S1) was a significant parasite.

I rigged up some batteries to get 12 Vdc, hooked up my multimeter inline with the batteries & USB charger, and measured a current draw of 0.169A on the input side of the unloaded charger (w/ or w/o the USB cable).

Using lorenfb's method, for this USB charger:
Energy (12V battery) = 0.169A X 12V X 24hrs X 21days = 1022.11 Wh = 1.02 kWh
Assuming 80% efficiency on the converter, the load energy loss on the main battery = 1.02 kWh / 0.8 = 1.28 kWh
For my 40 kWh battery, that's about a 3.2 % loss.
2018 Nissan Leaf S w/QC
Placed in action: 9/2018

GerryAZ
Gold Member
Posts: 2593
Joined: Mon Nov 22, 2010 6:47 pm
Delivery Date: 12 Jun 2011
Location: Phoenix, AZ

Re: Key-off battery drain

Mon Feb 03, 2020 12:09 pm

henrydehoja wrote:
Fri Jan 31, 2020 10:55 am
GerryAZ wrote:
Wed Jan 29, 2020 10:01 pm
That is much more loss of charge than I typically have. Did you leave something plugged in to the OBDII port? I typically see either the same SOC or 1% to 3% loss of charge when I return to the car after as much as a month.
Is that what you see on your 2019 model?
The SOC same or 1% to 3% loss is what I saw for both the 2011 and 2015. The 2019 has only been parked long term a couple of times, but so far the SOC has stayed about the same.
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; traded 8/10/2019 at 82,436 miles
White LEAF 2019 SL Plus purchased 8/10/2019

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