Become a MacRumors Supporter for $50/year with no ads, ability to filter front page stories, and private forums.

Septembersrain

Cancelled
Original poster
Dec 14, 2013
4,347
5,451
I know I used to read that it was good to let a lithium battery die all the way once a month or so for battery calibration.

Is this still the case? Will it do more harm than good? It will likely be traded in or sold within 2 years but if not, I'm okay with paying for a replacement through Apple.

I know Apple considers a charge cycle to be 50% up to 100% (What I read online).

I'm curious as it appears my battery sometimes dies much more rapidly even with the exact same use as always. Then it stays at 99% for over two hours.

Is the calibration off?
 

C DM

macrumors Sandy Bridge
Oct 17, 2011
51,392
19,460
I know I used to read that it was good to let a lithium battery die all the way once a month or so for battery calibration.

Is this still the case? Will it do more harm than good? It will likely be traded in or sold within 2 years but if not, I'm okay with paying for a replacement through Apple.

I know Apple considers a charge cycle to be 50% up to 100% (What I read online).

I'm curious as it appears my battery sometimes dies much more rapidly even with the exact same use as always. Then it stays at 99% for over two hours.

Is the calibration off?
A full discharge once in a while can help keep the battery meter calibrated properly or at least better. It doesn't really help the battery itself, and if it only happens once in a while it won't really do anything noticeably bad to the battery. If it happens fairly often or on a regular basis it can actually make the battery worse over time.

A full cycle is a 100% charge or multiple charges that add up to it, whether it's one 0 to 100 charge, two 50 to 100 charges, one 20 to 70 and one 40 to 90 charges, etc.
 

Septembersrain

Cancelled
Original poster
Dec 14, 2013
4,347
5,451
A full discharge once in a while can help keep the battery meter calibrated properly or at least better. It doesn't really help the battery itself, and if it only happens once in a while it won't really do anything noticeably bad to the battery. If it happens fairly often or on a regular basis it can actually make the battery worse over time.

A full cycle is a 100% charge or multiple charges that add up to it, whether it's one 0 to 100 charge, two 50 to 100 charges, one 20 to 70 and one 40 to 90 charges, etc.

Thank you. I haven't had my 7+ die all the way as of yet. I've had it since the second week of December so it's been over a month. Lately it has just started acting strange by charging up to 99% real fast but then sitting on 99% for about two hours. I don't think it's the new beta because it didn't do it right away after updating. It was about a week later.
 

Tech Fun

macrumors member
Apr 3, 2016
57
41
I would run the phone down 10 - 20% should be enough and then charge back up to 100% and charge for a further 2 hours to make sure it is fully charged.
If that fails to work maybe run the phone down to 1% try not to let it shut down and then charge back up like I described.
I do this with my phone roughly every 6-8 weeks and all seems good.

Good Luck
 
  • Like
Reactions: Septembersrain

Mlrollin91

macrumors G5
Nov 20, 2008
14,151
10,157
I would avoid letting your battery die completely if possible. Letting a lithium ion battery completely die can increase the rate at which it will degrade. Same goes for overcharging as well.
 
  • Like
Reactions: Septembersrain

deano1972

macrumors 6502a
Sep 16, 2016
557
239
United Kingdom
I would charge it when it's between 20 and 50% as a rule but maybe once every couple of months let it drain to 1% to calibrate .. but put it on charge before it switched itself off if possible
 
  • Like
Reactions: Septembersrain

Septembersrain

Cancelled
Original poster
Dec 14, 2013
4,347
5,451
I would plug it into the charger before I went to sleep every night and not worry about it. No need to do all this discharge stuff unless you are having trouble. Too much worry about the battery!

I am having trouble though. =(

It oddly gets stuck for two hours at 99% charged. When it's fully charged and being used, it'll lose a huge amount quickly. Then it'll taper off and start regulating properly.
 

Tech Fun

macrumors member
Apr 3, 2016
57
41
I would plug it into the charger before I went to sleep every night and not worry about it. No need to do all this discharge stuff unless you are having trouble. Too much worry about the battery!
I would read the post again
[doublepost=1486331299][/doublepost]iPhones typically stay at 100% for a while before starting to drop
 

Septembersrain

Cancelled
Original poster
Dec 14, 2013
4,347
5,451
Using my 6s right now. I went ahead and risked it dying. It stayed at 1% for almost an hour. So something definitely seems off. Hmm.

We shall see when it's fully charged if this issue is solved for me.
 

imagineadam

macrumors 68000
Jan 19, 2011
1,702
876
I would plug it into the charger before I went to sleep every night and not worry about it. No need to do all this discharge stuff unless you are having trouble. Too much worry about the battery!
I agree! I used to be obsessed with my battery and percentages but ever since I turned off the percentage and just use the phone and plug it in every night before bed everything is fine and no worries. I suggest OP does the same along with everyone else! And yes it's normal for the meter to stick at 100% or 99 for an hour or two after you stop charging and then eventually the meter will catch up. This is just the way iOS's algorithm is set up with how it reads the voltage of the battery and to give you the illusion you have more battery than you actually do at the beginning of a full charge.
 

Septembersrain

Cancelled
Original poster
Dec 14, 2013
4,347
5,451
It's better. No more issues with quick drain. It has the normal behaviour of staying at 100% for a while, then gradually going down. No more 100% to around 80% rapidly. It seems to be fixed to me. I'll have to see when I charge it again if it gets stuck at 99% for hours but I doubt it will.
 

M_Johnson

macrumors newbie
Feb 7, 2017
8
3
Mine also stays on 99% for a long time while charging! I hope it wont affect the battery life over time, if I unplug it before it get to 100%.
 

Septembersrain

Cancelled
Original poster
Dec 14, 2013
4,347
5,451
Mine also stays on 99% for a long time while charging! I hope it wont affect the battery life over time, if I unplug it before it get to 100%.

Hmm. I hope not. I'm about to have to charge my 7+ again. I'll see if it does the same issue with staying on 99% for one and a half to two hours.
 

decafjava

macrumors 603
Feb 7, 2011
5,388
7,769
Geneva
I would avoid letting your battery die completely if possible. Letting a lithium ion battery completely die can increase the rate at which it will degrade. Same goes for overcharging as well.
I was under the impression that the firmware prevents a complete discharge anyway? Not that is' a good thing to do.
 
Register on MacRumors! This sidebar will go away, and you'll see fewer ads.