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BR4DOKYBrazil

macrumors 6502a
Original poster
Jan 25, 2018
786
1,934
Londrina - PR / Brazil
I bought my iPhone 12 Pro Max and gave my old 11 Pro Max to my wife. Since the new device doesn't come with a charger, I'm using a Mophie wireless charger that I used only when traveling. I notice that every morning I remove my device from the wireless charger, the iPhone is a little warm. Doesn't this damage the battery in the long term? I know that this heating is normal because of the technology used in this type of charging, but I'm afraid to use it every day, since I used it only a few times a year during my travels.
 

akash.nu

macrumors G4
May 26, 2016
10,818
16,896
This will come down to the bottom line of how often you replace your devices. If it’s every couple of years like most then you shouldn’t see any issues with your day to day use generally.

If you keep it for longer then you might need an out of warranty battery replacement.

Personally, unless you’re planning to use the same device for a decade to come I won’t worry about it much. iPhone battery circuits only trickle charge after 80% so that users don’t need to worry about all this.
 
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ericwn

macrumors G4
Apr 24, 2016
11,817
10,396
Theoretically it will have an impact. To give you an anecdotal data point, I didn’t care with my 8+ at all and charge wirelessly everyday for almost two years prior to that mostly fast chargers. Battery health after 3.5 years is 87%. Fine with me. I’ve stopped worrying about it.
 

seezar

macrumors 6502a
Jan 18, 2018
567
582
I charged a XS Max for 2 years almost exclusively wirelessly and the battery health was down to 93%. Still a pretty decent percentage after two years in my opinion.

Perhaps if I made a point of not doing that I could have made the battery health not drop by quite that much but then I would have lost the convenience of every night just putting the phone on the upright wireless charging stand on my night stand.

All that to say, if it were me contemplating your question, I wouldn’t worry about it that much.

Another data point I have, my daughter has an iPhone 11 that she’s never wirelessly charged (didn’t use a wired rapid charger either) and after a year it’s down to 81%. One thing she does a lot is let the phones battery drop to near depleted levels. I think doing that can have a bigger impact than the additional heat of wireless charging.
 

The Game 161

macrumors Nehalem
Dec 15, 2010
30,217
19,449
UK
yeah the battery won't be damaged certainly if your phone is lasting you all done and charging at 50% as that will help it over time. never been able to get my pro Max below 30% by the end of the day I must admit.
 
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firoze

macrumors regular
Jul 3, 2011
239
83
I bought my iPhone 12 Pro Max and gave my old 11 Pro Max to my wife. Since the new device doesn't come with a charger, I'm using a Mophie wireless charger that I used only when traveling. I notice that every morning I remove my device from the wireless charger, the iPhone is a little warm. Doesn't this damage the battery in the long term? I know that this heating is normal because of the technology used in this type of charging, but I'm afraid to use it every day, since I used it only a few times a year during my travels.
I used my iPhone X with a Samsung wireless charger for three years, after which the battery capacity dropped to 83%. Which is not bad at all considering I am a heavy user and frequently let the battery drop below 20% charge. Letting the battery drop below 20% frequently will reduce the capacity far more than using a wireless charger.
 
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now i see it

macrumors G4
Jan 2, 2002
10,582
22,071
Actually charging a Lithium battery when it's cold is harder on it than charging it when it's warm. Warm is good (but not too warm) but hot is not. If the back of the phone feels warm during charging, that's totally fine. It's not harmful. When the phone feels HOT, that's when it should be taken off the charger or not charged or a smaller 5 watt charger should be used.
Typically that scenario only happens in the summer in a non air conditioned room in warmer climates (95°F and hotter days)
 

firoze

macrumors regular
Jul 3, 2011
239
83
Actually charging a Lithium battery when it's cold is harder on it than charging it when it's warm. Warm is good (but not too warm) but hot is not. If the back of the phone feels warm during charging, that's totally fine. It's not harmful. When the phone feels HOT, that's when it should be taken off the charger or not charged or a smaller 5 watt charger should be used.
Typically that scenario only happens in the summer in a non air conditioned room in warmer climates (95°F and hotter days)
Correct! If you really want to maximise the battery life of your phone then the best way would be to use the good old Apple 5watt wired charger. That will heat up the phone the least and will comfortably charge your 12 Pro Max overnight.
 

BR4DOKYBrazil

macrumors 6502a
Original poster
Jan 25, 2018
786
1,934
Londrina - PR / Brazil
The charger I use is the Mophie indicated by Apple. If I'm not mistaken, it is 7.5w. I believe it's at a cool speed, since I don't need a faster charger (more watts). I was only worried about why the device, even after it finished charging (100%), it remains a little hot, but nothing worrying.
 
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