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poakenfold

macrumors newbie
Original poster
Jan 24, 2016
6
4
Hi guys,

I know this question has been asked many times but i still haven't been able to get a solid answer.

If i keep iPhone plugged in to the wall charger at 100%, will it still draw power from the battery or from A/C? Will I be able to save a charging cycle and is this a good habit according to Apple?

Thanks in advance.
 

Newtons Apple

Suspended
Mar 12, 2014
22,757
15,253
Jacksonville, Florida
You would save a cycle by leaving on the charger. But a partial cycle will add up to equal a whole cycle after a while. While plugged in you device run on the battery so when you battery drops to like 97% the charging circuit kicks in and charges back to 100%.
 
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poakenfold

macrumors newbie
Original poster
Jan 24, 2016
6
4
You would save a cycle by leaving on the charger. But a partial cycle will add up to equal a whole cycle after a while. While plugged in you device run on the battery so when you battery drops to like 97% the charging circuit kicks in and charges back to 100%.
"You would save a cycle by leaving on the charger."
Thanks for your reply. I got what you said.
This means if:
Power being consumed by iPhone < Power being supplied by Adapter (Considering a scenario where no processor intensive tasks are being run) the charging circuit won't kick in..Right?
 

Mlrollin91

macrumors G5
Nov 20, 2008
14,120
10,106
"You would save a cycle by leaving on the charger."
Thanks for your reply. I got what you said.
This means if:
Power being consumed by iPhone < Power being supplied by Adapter (Considering a scenario where no processor intensive tasks are being run) the charging circuit won't kick in..Right?

No. Your iPhone is designed to charge to 100% then stop charging. It will discharge down to 97% and then it will start to charge back up to 100%. Then it will discharge to 97% and then recharge to 100%. This will go on and on all night long.

Now if you keep your phone in airplane mode, with absolutely nothing running, it will probably not discharge to 97% so it will not have to recharge back to 100%, but just know when you unplug your phone in the morning and it says 100%, it may not truly be at 100%.

I use an app called CoConut battery, and it gives you a more accurate battery readout vs. the % in the status bar. This uses current vs. max mAh to give you an accurate readout. Typically when I wake up in the morning my device says Its at 100%, but CoConut battery gives me a number between 98-99%. Therefore, I am losing 1-2% overnight even though the phone is plugged in because its discharging on its own so it doesn't overcharge.
 

Newtons Apple

Suspended
Mar 12, 2014
22,757
15,253
Jacksonville, Florida
"You would save a cycle by leaving on the charger."
Thanks for your reply. I got what you said.
This means if:
Power being consumed by iPhone < Power being supplied by Adapter (Considering a scenario where no processor intensive tasks are being run) the charging circuit won't kick in..Right?

The charger only charges the batteries and does not supply power to the device. Like the above poster said, it will slowly drain the batteries until the charging circuit detects it and kicks in the bring the battery back up to 100%.

You are worrying to much about battery cycles and if you can just forget about it and enjoy your phone. Worst care in a couple of years get the battery replaced but do not let the fear of battery cycles ruin your ownership of the iPhone.
 
Last edited:
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