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iPhone 13 Pro Max Does Fast Charging decrease battery life?

BR4DOKYBrazil

BR4DOKYBrazil

macrumors 6502a
Original poster
Jan 25, 2018
887
2,260
Londrina - PR / Brazil
It's my old question since I received my iPhone 11 Pro Max with the 18W charger at its launch.

I currently own Apple's 20w charger and use it every night and when I travel, I use my 7.5w Mophie Wireless Charging.

I'm afraid I'm shortening the battery life of my iPhone's, even though I know that neither Apple nor other companies would put this option if it really shortened battery life.

Once I read that the battery recharges fast to 80%, then the speed is reduced precisely so as not to harm the battery.
 
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It may decrease battery life a bit faster on the long run, but Apple optimizes the software to give a longer longevity to your battery. The battery will be good for a few years, even with fast charging. I'd say, use your iPhone as you intend to. Battery replacement is cheap and the difference in battery longevity between fast charging and regular charging doesn't justify to not take advantage of the convenience of fast charging in my opinion. Of course, if you know you'll never need fast charging, you can always use a 5W-7.5W charger for overnight charging. Wired charging will be better for battery longevity than wireless, because of the heating you get wireless
 
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BR4DOKYBrazil said:
It's my old question since I received my iPhone 11 Pro Max with the 18W charger at its launch.

I currently own Apple's 20w charger and use it every night and when I travel, I use my 7.5w Mophie Wireless Charging.

I'm afraid I'm shortening the battery life of my iPhone's, even though I know that neither Apple nor other companies would put this option if it really shortened battery life.

Once I read that the battery recharges fast to 80%, then the speed is reduced precisely so as not to harm the battery.
Click to expand...
The high voltage burst stops once it reaches 50%. After that it usually drops to around 10W and keeps slowing down as it gets closer to 80%.
After that it’s usually trickle charging at 0.7W.

You’re fine with using 20W adapter or higher as long as you don’t have a case on. Cases make it harder for the heat to dissipate during the high voltage burst which is the primary reason for battery deterioration. I sometimes look for excess heat during fast charging and would remove the case if I find it getting warmer than I’d like.
 
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fwmireault said:
It may decrease battery life a bit faster on the long run, but Apple optimizes the software to give a longer longevity to your battery. The battery will be good for a few years, even with fast charging. I'd say, use your iPhone as you intend to. Battery replacement is cheap and the difference in battery longevity between fast charging and regular charging doesn't justify to not take advantage of the convenience of fast charging in my opinion. Of course, if you know you'll never need fast charging, you can always use a 5W-7.5W charger for overnight charging. Wired charging will be better for battery longevity than wireless, because of the heating you get wireless
Click to expand...

OhMyMy said:
The high voltage burst stops once it reaches 50%. After that it usually drops to around 10W and keeps slowing down as it gets closer to 80%.
After that it’s usually trickle charging at 0.7W.

You’re fine with using 20W adapter or higher as long as you don’t have a case on. Cases make it harder for the heat to dissipate during the high voltage burst which is the primary reason for battery deterioration. I sometimes look for excess heat during fast charging and would remove the case if I find it getting warmer than I’d like.
Click to expand...

I really appreciate your help! Thank you for answering my question!
 
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Multiple threads on this but yes wireless charging is largely inefficient and generates excess heat which is not good on the battery. 20W charging also generates heat but in my opinion, I rather fast charge the device than wireless charge it and waste energy. I have been 20W charging for a while and it is still at good battery health.
 
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Natzoo said:
Multiple threads on this but yes wireless charging is largely inefficient and generates excess heat which is not good on the battery. 20W charging also generates heat but in my opinion, I rather fast charge the device than wireless charge it and waste energy. I have been 20W charging for a while and it is still at good battery health.
Click to expand...
Tks for reply, Nat!
 
BR4DOKYBrazil said:
Tks for reply, Nat!
Click to expand...
I don’t think i buy this claim based on my anecdotal experience. I have an 8plus with nearly 1000 cycles and the health is 80%. I’ve been using wireless charging 2 1/2-3 years and have noticed a very gradual decrease in bat health. I don’t do any of that pedantic 40-80% stuff either. Charge to 100% and will go down to 10%. I’ve had the phone for 3 1/2 years.

I do think some batteries are probably better samples than others. Usage patters also play a part.

Battery replacement is relatively inexpensive compared the the cost of the phone. I’m puzzled why people obsess over this issue so much. ?
 
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BR4DOKYBrazil said:
It's my old question since I received my iPhone 11 Pro Max with the 18W charger at its launch.

I currently own Apple's 20w charger and use it every night and when I travel, I use my 7.5w Mophie Wireless Charging.

I'm afraid I'm shortening the battery life of my iPhone's, even though I know that neither Apple nor other companies would put this option if it really shortened battery life.

Once I read that the battery recharges fast to 80%, then the speed is reduced precisely so as not to harm the battery.
Click to expand...
My ideal setup is

5W wired charging when I sleep ~8hrs

30W wired car charging to top up to 50% within a 30 min drive

Avoid wireless charging as it generates more waste heat than actual input energy received to battery.

My view on wireless charging is as a luxury for those who cannot be bothered to use wired charging. It's cool to show to other people though. so there's that.
 
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tedley said:
I don’t think i buy this claim based on my anecdotal experience. I have an 8plus with nearly 1000 cycles and the health is 80%. I’ve been using wireless charging 2 1/2-3 years and have noticed a very gradual decrease in bat health. I don’t do any of that pedantic 40-80% stuff either. Charge to 100% and will go down to 10%. I’ve had the phone for 3 1/2 years.

I do think some batteries are probably better samples than others. Usage patters also play a part.

Battery replacement is relatively inexpensive compared the the cost of the phone. I’m puzzled why people obsess over this issue so much. 😀
Click to expand...
I watched a video that they confirmed that some iPhone's actually come with 102 or 104% battery life. That's why some devices take a long time to get out of 100%.
 
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Yes compared to the 5w. Because the heat genereted.. usually i attach peltier phone cooler when i must use fast charging to decrease the temp..
 
BR4DOKYBrazil said:
It's my old question since I received my iPhone 11 Pro Max with the 18W charger at its launch.

I currently own Apple's 20w charger and use it every night and when I travel, I use my 7.5w Mophie Wireless Charging.

I'm afraid I'm shortening the battery life of my iPhone's, even though I know that neither Apple nor other companies would put this option if it really shortened battery life.

Once I read that the battery recharges fast to 80%, then the speed is reduced precisely so as not to harm the battery.
Click to expand...
Apple battery's are tested to fully charge cycle 1000 times before 50% capacity. This would get about 3 years of useful life if your device was drained to 0% every night. If you typically end with 25%... well, it will last longer. Often the devices last much longer 6 - 7 years.

Here is a bit more information:
www.apple.com

Batteries

Maximize the life and lifespan of the lithium-ion battery in your iPod, iPhone, iPad, or MacBook. Learn how to service and recycle it, too.
www.apple.com
 
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There's definitely something that's changed in the last few years. My iPhone 6S was at ~85% health after 4 years of use. I wasn't careful, just used the phone as I needed: typically down to ~30-40% by the end of the day and then charge back to/sit at 100% overnight (using an iPad 12 W charger). This model did not support fast charging or Qi.

I'm now seeing a lot of second hand iPhone 12 (inc mini/pro/max) models with battery health down to 85-90% after just 12-15 months use.
 
I have been studying Li-Ion batteries a lot lately. My conclusion is that fast charging with ~20W should not be a problem, as long as it happens while the cell temparture is in the optimal window of between 0 to 45 degrees Celsius. The battery-management-system of the iPhone should be able to monitor the temperature of the battery cell and adjust the charging rate accordingly. Although I haven't tested if this is the case. Just assuming Apple's battery tech is state of art.

One thing I would try to avoid is overnight charging to 100%. Li-Ion cells should not stay at 100% charge for long periods of time. If you regularily charge overnight, your battery is at 100% for most of the night. That is going lead to a higher degradation rate for sure.
 
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I’m sticking to using a 12 watt charger with a HomeKit smart plug and a Shortcuts Automation script to control the charging. I stick to the 80/20 rule. When I charge overnight the script will turn off the smart plug at 80% charge and turn on Low Power mode.
 
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I think it’s intentional coding targeting older devices. No way to audit the validity of that claim of course.

Free iOS updates have three purposes. (There’s a reason why they’re free).
1: To break features that used to work properly in a prior release so that users become desperate for bug fixes throughout the year.
2: To roll out new features
3. To slowly kill off older devices so that a person has to eventually purchase a new device.

Yes that sounds pretty cynical, but nothing in those three points conflicts with reality.
 
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This never happened to me. I still have an iPhone 6S on iOS15 which works flawlessly. Same with an 8. They always work better with newer iOS versions in my experience.
 
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planteater said:
I've been using my 140w MBP charger on my 13 Pro Max recently. Talk about fast charging! Anyone else doing this? Am I destroying my battery life?
Click to expand...
Wouldn’t matter if you’re using a 500w charger, apple has a limit in place on how much watts a iPhone can receive while charging.

1647567982804.jpeg
 
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