LeafTaxi
Posts: 27
Joined: Mon Jan 14, 2019 11:54 am
Delivery Date: 14 Jan 2019

deplete a battery for better pack health?

Wed Jul 10, 2019 2:02 pm

Let's say that your car charged to 100% overnight. Then you decide to take a sick day/day off. It's 85F at breakfast, and the car already has "6 temp bars" without any driving (probably get to 7 bars by afternoon).

Do you try to deplete the battery (e.g. turn-on the A/C) to bring the SOC down to 95%? Or just leave it parked at 100% SOC for 24 hours in summer weather?

(I wonder if I could power a garage-window A/C unit from a 2kw inverter off the 12v battery?).

SageBrush
Posts: 4907
Joined: Sun Mar 06, 2011 2:28 am
Delivery Date: 13 Feb 2017
Location: NM

Re: deplete a battery for better pack health?

Wed Jul 10, 2019 2:25 pm

LeafTaxi wrote: Do you try to deplete the battery (e.g. turn-on the A/C) to bring the SOC down to 95%?
Heating up the battery more to lower the SoC is a debatable strategy at best
2013 LEAF 'S' Model with QC & rear-view camera
Bought off-lease Jan 2017 from N. California
Two years in Colorado, now in NM
03/2018: 58 Ahr, 28k miles
11/2018: 56.16 Ahr, 30k miles
-----
2018 Tesla Model 3 LR, Delivered 6/2018

LeftieBiker
Moderator
Posts: 13453
Joined: Wed May 22, 2013 3:17 am
Delivery Date: 30 Apr 2018
Location: Upstate New York, US

Re: deplete a battery for better pack health?

Wed Jul 10, 2019 3:19 pm

Your use of the word "deplete" is misleading here - that implies draining it fully or almost fully. If it were me I'd drive the car to get down to the low nineties - and I have done so quite a few times. Running the A/C might blow hot air on the pack. Still, if you can't drive it, running the A/C (and maybe the heater with it) is better than leaving it at indicated 100% in hot weather.
(I wonder if I could power a garage-window A/C unit from a 2kw inverter off the 12v battery?).
Interesting idea, but then you'd have to connect the car into that setup whenever you wanted to use it. I have an alternate suggestion: if you usually get 100% at about the same time every night, try using a daily charge timer that stops at about 95%.
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.

Oilpan4
Gold Member
Posts: 955
Joined: Wed Jan 09, 2019 10:51 pm
Delivery Date: 10 May 2018
Leaf Number: 004270

Re: deplete a battery for better pack health?

Wed Jul 10, 2019 9:36 pm

The car draws around 700 watts of power continously when you turn it on, leave it in park, no A/C, no heat, no additional lights on.
Leaving it on will run the battery down, it just takes a while.
2011 white SL leaf with 2014 batt.
Chargers: Panasonic brick moded for 240v, duosida 16a 240v and a 10kw setec portable CHAdeMO
Location: 88103

LeafTaxi
Posts: 27
Joined: Mon Jan 14, 2019 11:54 am
Delivery Date: 14 Jan 2019

Re: deplete a battery for better pack health?

Thu Jul 11, 2019 2:25 pm

LeftieBiker wrote:Your use of the word "deplete" is misleading .
You're right; that was the wrong word. I meant "reduce SOC a bit."
Heating up the battery more to lower the SoC is a debatable strategy at best
From what I've read here, the worst thing is the number of hours spent at high temp + high (or low) SOC. Drawing 1.5kw will raise temps a bit, but I've never seen street driving add a temp bar. I can drive Uber on city streets for 120 miles over 4 hours straight, taking SOC from 100% down to 20%, and not see an additional temp bar. But if I do a couple of 20-mile airport runs on the expressway, then I get an extra temp bar.
LeftieBiker wrote: try using a daily charge timer that stops at about 95%.


That would be nice; I have the S, which has no stop timer. Also, my use case is unusual (Uber driver). I usually drive AM rush hour, PM rush hour, then early bar hours, so I charge 2-3 times per day (about 8 hours of driving per day). In summer, the car will go 4+ hours (longer than I care to drive at once), so I don't really need to charge it to 100%. Rather than setting a stop timer two or three times per day, It would be really nice if Nissan had an 80% "mounutain mode" (I'm sure I'm not the first person to say that).

LeftieBiker
Moderator
Posts: 13453
Joined: Wed May 22, 2013 3:17 am
Delivery Date: 30 Apr 2018
Location: Upstate New York, US

Re: deplete a battery for better pack health?

Thu Jul 11, 2019 2:52 pm

Nope, we've been clamoring for them to restore the 80% mode for years - to no avail.
That would be nice; I have the S, which has no stop timer.
You can fudge it: set the start time late enough so it will fail to reach 100% by about 5-10% when you leave in the morning. Charging usually adds about 5-6% per hour, if that helps.
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.

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