Page 1 of 3

How important is charging only to 80%?

Posted: Sun Jun 25, 2017 3:08 pm
by ByeFO
Is there a problem if I need to charge the Leaf to 100% for the one day a week I have an after-work errand to run?

I usually charge it to 80% most work days. I get the Leaf "low battery warning" just a few miles from home, so no big deal. I prob couldn't add the after-work errand on 80% charge day, though.

Thanks!

Re: How important is charging only to 80%?

Posted: Sun Jun 25, 2017 3:22 pm
by alozzy
No problem at all, in fact just the opposite - doing a full charge periodically is good for the pack. Just don't leave the car at 100% SOC for more than an hour or two and try to avoid charging when it's hot out

Re: How important is charging only to 80%?

Posted: Sun Jun 25, 2017 3:23 pm
by Dooglas
The same people who advise you to not charge above 80% also warn you to not discharge below 20%. Sounds like you are going to break one "rule" or the other. My advice is to use your car in whatever way meets your needs.

Re: How important is charging only to 80%?

Posted: Sun Jun 25, 2017 4:25 pm
by hackdroot
I charge my leaf to 100% 4-5 days a week. It finishes charging about 30 minutes before I leave in the morning. I bought the car as a commuter and use it as such.

Re: How important is charging only to 80%?

Posted: Sun Jun 25, 2017 5:21 pm
by ByeFO
Thanks!

Re: How important is charging only to 80%?

Posted: Sun Jun 25, 2017 6:26 pm
by GerryAZ
I have always charged to 100% (both 2011 and 2015). I also typically discharge to LBW or VLBW and battery deterioration on both vehicles was and is commensurate with others in Phoenix who tried to "baby" their batteries so I recommend that you charge it and drive it as you need. If you can avoid charging when the battery is hot and minimize the time that it sits at 100%, those are probably good ideas. Unfortunately, I would never be able to charge in the summer if I worried too much about charging when at 8 temperature bars or higher. I just started a QC at 9 bars and expect it to be 10 or 11 bars when finished.

Re: How important is charging only to 80%?

Posted: Sun Jun 25, 2017 6:42 pm
by Jedlacks
hackdroot wrote:I charge my leaf to 100% 4-5 days a week. It finishes charging about 30 minutes before I leave in the morning. I bought the car as a commuter and use it as such.


+1

That is exactly what I do.

Re: How important is charging only to 80%?

Posted: Sun Jun 25, 2017 9:24 pm
by LeftieBiker
Dooglas wrote:The same people who advise you to not charge above 80% also warn you to not discharge below 20%. Sounds like you are going to break one "rule" or the other. My advice is to use your car in whatever way meets your needs.


Who exactly advises people "to not charge above 80%"?

Re: How important is charging only to 80%?

Posted: Sun Jun 25, 2017 9:45 pm
by EVDRIVER
Dooglas wrote:The same people who advise you to not charge above 80% also warn you to not discharge below 20%. Sounds like you are going to break one "rule" or the other. My advice is to use your car in whatever way meets your needs.


Those are apples and oranges comparisons that leave out the relevant details.

Re: How important is charging only to 80%?

Posted: Sun Jun 25, 2017 11:39 pm
by cwerdna
LeftieBiker wrote: Who exactly advises people "to not charge above 80%"?

The '13 Leaf manual (last US model year to have a setting to charge to 80%) does.

OP can download a copy from https://owners.nissanusa.com/nowners/na ... nualsGuide and search for 80%. It's all over the place, besides referring to 80% mode as long life mode and "improves battery longevity".

Some bits from page EV-24
To maximize vehicle range, NISSAN recommends
using the default setting, long distance
mode (100% charge). To maximize the battery’s
useful life, use the following driving and charging
habits where possible:
...
Avoid sustained high battery state of charge
(caused, for example, by frequently charging to
100% state of charge and/or leaving the battery
above 80% state of charge for long periods of
time).
• Allow the battery charge to be below at least
80% before charging

Unfortunately, Nissan has never publicly provided us with any battery degradation info for 80% vs. 100% or any other % SoC vs. temp and/or temp. Nor have they said how much better it is (if any) to only charge to 80% or if it's bad to run below 20% or whatever %.

The only warnings I quickly found about low SoC are along these lines:
To prevent damage to the Li-ion battery:
...
Do not leave your vehicle for over 14
days where the Li-ion battery available
charge gauge reaches a zero or near
zero (state of charge).

Avoid leaving your vehicle for over 14 days
where the Li-ion battery available charge gauge
reaches a zero or near zero (state of charge).