They were probably referring to the "drain every once in a while" thing. These ain't cadmium
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Is it harmful to keep iPhone always plugged in to save battery cycles?
- Thread starter Aneef
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A somewhat related question: I bought the iPhone 8, but I am outside the country and the phone will remain in the box for two months brand new and unused. Should it be a problem with potential battery drain? I can have my folks open the box, turn on the phone and check charge status, and top it up if necessary.
I’ve seen negative effects on several laptops of always being plugged into the wall. My dad’s laptop battery has gone almost completely flat because it rarely ever leaves the desk, always being plugged in. For years.
I’d say it’s not harmful unless you’re never using the battery. I wouldn’t worry about it though, just keep it above 20% and you’ll be fine.
I’d say it’s not harmful unless you’re never using the battery. I wouldn’t worry about it though, just keep it above 20% and you’ll be fine.
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lol wut
Yes it is. All modern electronics batteries are. Apple’s batteries are lithium polymer, but still lithium. Long term, a battery that is constantly full and never used will degrade. OP should just use his phone and charge when it hits 20%, or any time before that.
Dell Inspiron 15” of some sort from ~2012 ish. Any laptop made in the last 15 years or so has a Li-ion battery.
if your battery health degrades faster than normal I would think the battery is defective and there is no way to prevent that.
Hopefully a defective battery is caught while still under warranty or in other cases Apple will still replace it after warranty if they feel that it degraded faster than it should have
Hopefully a defective battery is caught while still under warranty or in other cases Apple will still replace it after warranty if they feel that it degraded faster than it should have
The drain every once in awhile is meant for those who leave their devices plugged in 100%. 10 years ago li-ion batteries kept at 100% all the time would fail quickly (you'd find out cuz you'd unplug and only last 30 minutes). Today, batteries handle this much better than they did in the past.
These quotes come from Isidor Buchmann in his book "Batteries in a Portable World" (author of batteryuniversity.com):
These quotes come from Isidor Buchmann in his book "Batteries in a Portable World" (author of batteryuniversity.com):
If it works anything like MacBook Pros, it will charge it to true 100% once, and still show 100% until it drops to the low 90s, and then charges it to 100 again. None of this is shown, it just says 100% the whole time.
Correct. The iPhone battery reader is really vague between 95% and 100%. So that cycling when at 100% is a 5% cycle, from what I can tell via coconutBattery - that is not visible to the user (unless the user can see the exact mAh). The phone will always report 100% but stop charging at true 100%, drop to 95% (while displaying 100%) then charge again - repeating this over and over if plugged in all the time.
This is why, if you are charging your phone, and at 96% unplug your phone and quickly plug it back in, sometimes it will say 100%. And why if you leave your phone on the charger for hours after it says 100%, it seems to take FOREVER to move off of 100%.
I kept my 6+ plugged in at my desk basically every work day for almost 2 years. It went from 103% design capacity to 99% after 240 cycles. I think Apple does a much better job than Dell at keeping their batteries healthy at 100%.
I too had a Dell Laptop that I kept plugged in all the time, the 65whr battery barely kept a 20 min charge after just a year.
[doublepost=1506627759][/doublepost]
This is the best advice. Don't worry about the battery. Apple does a great job of taking care of it for you. My wife lets her phone drain to 0%, just uses it like normal while I baby my battery - her design capacity after 300 cycles was almost identical to mine.
So @Newtons Apple has the best advice here.
If you do want to care for your battery... keep it out of the heat, try not to let it go below 20% charge, and enjoy your phone.
Correct. The iPhone battery reader is really vague between 95% and 100%. So that cycling when at 100% is a 5% cycle, from what I can tell via coconutBattery - that is not visible to the user (unless the user can see the exact mAh). The phone will always report 100% but stop charging at true 100%, drop to 95% (while displaying 100%) then charge again - repeating this over and over if plugged in all the time.
This is why, if you are charging your phone, and at 96% unplug your phone and quickly plug it back in, sometimes it will say 100%. And why if you leave your phone on the charger for hours after it says 100%, it seems to take FOREVER to move off of 100%.
I kept my 6+ plugged in at my desk basically every work day for almost 2 years. It went from 103% design capacity to 99% after 240 cycles. I think Apple does a much better job than Dell at keeping their batteries healthy at 100%.
I too had a Dell Laptop that I kept plugged in all the time, the 65whr battery barely kept a 20 min charge after just a year.
[doublepost=1506627759][/doublepost]
This is the best advice. Don't worry about the battery. Apple does a great job of taking care of it for you. My wife lets her phone drain to 0%, just uses it like normal while I baby my battery - her design capacity after 300 cycles was almost identical to mine.
So @Newtons Apple has the best advice here.
If you do want to care for your battery... keep it out of the heat, try not to let it go below 20% charge, and enjoy your phone.
Indeed, just thought I’d mention my experience with it.
We have an office phone for the on call person to take home. It was left plugged in for 2 weeks straight unbeknownst to me. It was shot and couldn’t hold a charge for more than 15 minutes after that. I charge overnite every nite and I’m good all day long. That’d be 365 charges per year. I generally keep it a couple years, longer now with these crazy prices but have never depleted a battery yet. If I do I’ll either get it replaced or it’s new phone time. But don’t leave it plugged in to try and save cycles. Not a good idea, just enjoy and use often.
Looks like it’s this one:
https://itunes.apple.com/gb/app/battery-life-check-batterys-runtimes/id1219864349?mt=8
I wouldn’t trust it......here’s the reading for my 1 year old 7 plus:
I’ve switched from every year to only when it’s necessary and I feel like category.