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Kendo

macrumors 68020
Original poster
Apr 4, 2011
2,228
686
I don't wear it when I sleep and I don't want it to perpetually charge at 100% overnight. I noticed when I take off my watch and just let it lie on my desk, it loses 20% over the course of 8 hours. Is it best to just power it down?
 

revmacian

macrumors 68000
Oct 20, 2018
1,745
1,461
USA
I have the Apple Watch series 4, and I had a series 3 prior to that. I only remember actually powering my watches down once. They always remained on their chargers overnight, every night, and I’ve not seen any problem with them. My current s4 is working perfectly as far as I can see and battery life is great.
 

deeddawg

macrumors G4
Jun 14, 2010
11,347
5,332
US
I don't want it to perpetually charge at 100% overnight.
Why not? You know these things have smart charging circuitry nowadays, yes? It's not like last century's constant-current trickle chargers.
 

Kendo

macrumors 68020
Original poster
Apr 4, 2011
2,228
686
Why not? You know these things have smart charging circuitry nowadays, yes? It's not like last century's constant-current trickle chargers.

Just seems like a waste no? I mean if my watch normally drops 30% over the course of 9 hours (10pm to 7am), then obviously it is charging it 30% every night to get it to a constant 100. So over the course of 7 days, that is 210% extra charging (or two full cycles a week), or basically 100 full cycles a year. That seems like a waste to me especially when I don't use the watch at night when I am sleeping.
 

Akrapovic

macrumors 6502a
Aug 29, 2018
858
1,783
Scotland
Why not? You know these things have smart charging circuitry nowadays, yes? It's not like last century's constant-current trickle chargers.

Best for long term battery life to not keep it at 100% for an extended period. Idealy the watch would have the Optimise battery charging option from the iPhone.

--

I just wear mine at night. Full charge in an hour during the day. Works amazing as a silent morning alarm.
 
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Kraizelburg

macrumors 6502
Nov 10, 2018
430
108
Spain
Just seems like a waste no? I mean if my watch normally drops 30% over the course of 9 hours (10pm to 7am), then obviously it is charging it 30% every night to get it to a constant 100. So over the course of 7 days, that is 210% extra charging (or two full cycles a week), or basically 100 full cycles a year. That seems like a waste to me especially when I don't use the watch at night when I am sleeping.
I was in the same situation as you and what I ended doing is putting my AW series 4 to airplane mode every night. It saves lots of battery.
 

ReardenMetal

macrumors regular
May 1, 2015
239
104
Los Angeles
I tend to finish the day with my S4 somewhere around 30-50%, depending on the day.
I don’t like the idea of an overnight trickle charge either.
What I do is leave it powered on overnight because powering it off and on every day is slow and adds senseless friction to my routine.
When I first wake up, I place the watch on the charger while I’m getting ready. It tops off quickly, somewhere in the 80%-100% range. Problem solved. Helps extend overall battery life. People can debate that.
 

deeddawg

macrumors G4
Jun 14, 2010
11,347
5,332
US
Just seems like a waste no? I mean if my watch normally drops 30% over the course of 9 hours (10pm to 7am), then obviously it is charging it 30% every night to get it to a constant 100.

You're also assuming the watch is as "active" when on the charger as when it is not. I'm not so sure that it the case.

Do whatever you think best, my point is only to convey information as many tend to have some carryover ideas of battery charging that don't apply to today's smart charging systems.

As for me, a turned-off watch doesn't work as an alarm. Phone is downstairs and not in the bedroom. Dresser-top clock radio doesn't do fancy per-day alarm schedules like the watch does.
 

Jim Lahey

macrumors 65816
Apr 8, 2014
1,180
2,014
Sunnyvale
Just seems like a waste no? I mean if my watch normally drops 30% over the course of 9 hours (10pm to 7am), then obviously it is charging it 30% every night to get it to a constant 100. So over the course of 7 days, that is 210% extra charging (or two full cycles a week), or basically 100 full cycles a year. That seems like a waste to me especially when I don't use the watch at night when I am sleeping.

No. When the watch is on charge, power is taken directly from the mains source and so doesn't drain the battery. It's probably more complicated than that, but that is my understanding of how these modern devices handle constantly being connected to power (the device doesn't use the battery).
 

deeddawg

macrumors G4
Jun 14, 2010
11,347
5,332
US
Best for long term battery life to not keep it at 100% for an extended period. Idealy the watch would have the Optimise battery charging option from the iPhone.
I don't believe the charging circuitry keeps it at a full 100% -- my watch is always ambient temp in the morning, so it's been relatively quiescent in terms of any charging. Acts pretty much just like my phones have been.

With my S2, S3, and S4 watches I never noticed any battery degradation in the year I'd owned them.

Spec for the watch is retain 80% capacity at 1000 full charge cycles. Twice the spec for phones. My iphone7 was three years old when I bought my XS - didn't show any apparent battery degradation and also saw the same overnight charge behavior.

It's my opinion that it really doesn't matter, especially if your expected lifetime of the device is under three years. Worst case, battery replacement is $79 by Apple.
 
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Otflyer

macrumors 65816
Nov 14, 2017
1,431
968
SF Bay Area
Put my S0 watch on the charger every night for 2.5 yrs. battery still charged to 100% when sold. My S3 and Current S4 go on the charger every night also. Not to worry.
 

Killbynumbers

macrumors 6502
May 29, 2019
266
188
Just use your watch how you want and don't worry about the battery. You won't ruin the battery no matter what you do.

I like to wear a watch 24/7 so every year, I buy 2-3 Apple watches. This year, I have two series 4 watches and a series 3 watch paired to my phone. When one needs charging, I put on another and charge the other one. It stays on the charger until the next day or two and the battery still lasts today just as it did on day one. My series 3 watch is two years old now and it too still lasts as good as it did on day one. It even sits on the charger for sometimes a week or two before I wear it and it's never ruined the battery.
 
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TrueBlou

Contributor
Sep 16, 2014
4,418
3,280
Scotland
I don’t think any of my Apple Watches have ever been switched off, I just pop them on the charger - never been an issue.
But I suppose if it bothers you, you could try putting it on airplane mode overnight to save some juice.
 
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