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Yeah, that’s why I mentioned wirelessly charging. It generates heat regardless of charger quality. You and I both know that Belkin is good, yet it isn’t enough to prevent your wife’s 15PM from dropping to unacceptable levels. The plate being too hot to touch half an hour later is ludicrous - 5w chargers that heat up are good to go in a few minutes (it has happened to me, though not to the extreme you mentioned earlier). The new battery should perform more normally, even with a fast charger.

Now, the question is… (obviously assuming no fires, of course) what can the consequence of the 5w charger outputting 7-8w be? Can that performance over-capacity do something to the phone, assuming the charger is “strained” but still functioning normally? Apple stated until they sold it, iirc, that it was compatible with every iPhone. Or is it just efficiency loss and in spite of the yellowing it should be “fine”? (Even though it is obviously not performing as intended. I really don’t think yellowing due to heat is expected behaviour).

I just unplugged my 16 Plus, but it is at 100% so it is trickle charging. I’ll touch the Power Adapter next time I charge it from below 80%.


This is something I wonder, too: slower (arguably cooler, in spite of the brick itself) charging for longer, or faster (but not too fast and not too hot, like wireless) charging with more heat but a shorter time charging? Say, like I charge once every year or so, a 20w.

Which of those two options is better?

I am inclined to say that they are the same: after all, even with no scientific test, people have shared results left and right; unlike wireless charging which kills health pretty predictably, neither the 5w or the 20w Power Adapters seem to have a negative result.


The comparison between adapters seems, like you said, luck of the draw.

Yeah, that is pretty much my conundrum. I’ve used the 5w for years on end with no negative results. Should strong evidence arise and conclusively prove that the 20w is better than the 5w for every usage pattern, I’ll gladly switch - after all, were that to be the case, then it would be all benefit: faster charging, no heat, and no health degradation more than that for which my usage pattern is responsible.


So I think the conclusion is very simple: use a 5w if it doesn’t get ridiculously hot; otherwise use a 20w. Regardless of your selection, avoid wireless charging and heat, and your device will probably be completely fine.

Some family members cycle their devices a lot more than me. They’ve charged overnight with a 5w regardless of percentage, and the devices are fine. I’m using an iPhone 8 (which, as I dislike breaking tradition I just keep charging with the 5w). 2261 cycles. 76% health. iOS 14. The device is completely fine.

Had it been charged with a wireless charger, the battery would probably be gone. Perhaps even not updating would not be enough to counteract the massive battery failure.

I would not know, because I haven’t degraded an original device enough to know whether a really low health degrades battery life.

Funnily enough… I have a device with battery failure. A family member’s iPhone 6s on iOS 10. It dropped below 80% after one year and 300 cycles. As my motto is “who cares about battery health and replacements, anyway?”, I have it after my family stopped using it. It shows anywhere between 60 and 70% health today. The battery “failed” eight years ago.

Battery life is like-new. 7-8 hours of light SOT, 6 hours of light cellular. It failed eight years ago. I can’t give a better reason for why I don’t care about health than that one.
Have you tried the new $39 apple dynamic power charger that one could be the best.
 
Been using the 5w charger since my first iPhone 4 all the way up to my 14 pro. Getting the 17 pro at the end of the month and I bought the 20w charger as I didn’t feel like buying a usb-a to c cable as I will just use the one that comes in the box. Planning on plugging in every night overnight like I always have with optimized battery charging on. I’m assuming my health will be fine. Since I’m a 2-4 hour SOT a day user in guessing iOS will probably suggest I set my charge limit to 80%. We will see how the health degrades in the coming years but I have a feeling my obsession with the 5w charging overnight will be put to rest as it should.
 
Slow charging is better for battery as less heat is being generated. If charging overnight, I might consider a 5W charger. However for now, I have decided to go with the 20W charger for my new 17 Pro Max.
 
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Been using the 5w charger since my first iPhone 4 all the way up to my 14 pro. Getting the 17 pro at the end of the month and I bought the 20w charger as I didn’t feel like buying a usb-a to c cable as I will just use the one that comes in the box. Planning on plugging in every night overnight like I always have with optimized battery charging on. I’m assuming my health will be fine. Since I’m a 2-4 hour SOT a day user in guessing iOS will probably suggest I set my charge limit to 80%. We will see how the health degrades in the coming years but I have a feeling my obsession with the 5w charging overnight will be put to rest as it should.
Your health should be fine, as for your new phone, you will find out in 2-5 years.
 
surely the point of optimised charging is that the OS determines when to draw power from the charger based on rules. if you look at your battery stats I find it interesting that apple classes anything less than 20w to be a slow charger, and shows up yellow, as opposed to green in the stats.
 
surely the point of optimised charging is that the OS determines when to draw power from the charger based on rules. if you look at your battery stats I find it interesting that apple classes anything less than 20w to be a slow charger, and shows up yellow, as opposed to green in the stats.
What is interesting that the official Apple 5W charger does not show as “Slow Charger” with yellow status that you usually get. I guess this aligns with some people’s reporting that this adapter draws more than 5W while overheating.

My car’s carplay port and another charger that I have at home (Amazon firestick adapter which is 5W) they do show as “Slow Charger”.
 
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I've always used a 5w charger with previous phones (and still use it with my Apple Watch), but have moved up to the 20w charger for my 17 Pro. My thinking is that if Apple engineered the phone to dissipate the amount of heat generated when using a 40w charger, or even worse a 25w wireless one, I'm still pampering the battery when using a 20 watt brick, especially since I'm only charging to 80%.
 
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OMG, my battery is degrading!!! 🙀 I won't be able to function today or sleep tonight because of the horrible anxiety this causes! Anything below 95% is totally unacceptable. I've spent hours researching this topic, bought the proper chargers, only charge to 80%, and set a timer so I don't accidentally over charge. Even if I fall asleep, the timer wakes me up so I can unplug. This is SERIOUS you guys. I don't understand how you aren't as stricken with worry about a degrading phone battery. And DON'T tell me it's free with AppleCare or $99 otherwise. NO! Absolutely not! I want the ORIGINAL battery, because once the phone is opened, it's RUINED! OMG you guys my phone battery, chargers, cables, I'm SO overwhelmed. I'm LITERALLY SHAKING right now!

/s
You really shouldn't make fun of people who suffer from anxiety and panic disorders. Those are real issues millions of people cope with every day.
 
just charge in front of a fan and u have the best of both worlds
Not sure whether you meant that as humor or not, but the major cordless tool manufacturers' rapid chargers now all incorporate fans to (attempt to) reduce battery temperatures during rapid charging, and some battery designs include air channels that permit airflow through the interior of the battery.
 
Not sure whether you meant that as humor or not, but the major cordless tool manufacturers' rapid chargers now all incorporate fans to (attempt to) reduce battery temperatures during rapid charging, and some battery designs include air channels that permit airflow through the interior of the battery.
Using a small USB fan - has made it so I don't get overheating messages on my Apple Watch Ultra rapid charging anymore - charges significantly faster too - and nice to take it off the charging puck without it being burning hot. Definitely makes a huge difference in that aspect.
 
I'm thinking. Instead of using the 5W brick that overheats... I could use the Apple 20W with a power regulator to 5W :)

Or
 
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Slow charging isn’t too bad - I just ran a test on my 16 Plus, running iOS 18. Apple 5w Power Adapter with a 2m Belkin USB-C to USB-A cable. Started charging at 54%. 1h 23 minutes to 80%, and 2h 41 minutes in total to 100%.

So: 1h 23 min 54%-80%: 83 min needed to charge 26%: 3.19 min/%. If it were linear: 255 min 0-80%, or 4 hours and 15 minutes.

80-100%: 1h 18 min, or 78 min needed to trickle charge the final 20%. 3.9 min/%. Or about 22.2% slower when it trickle charges.

Total estimated 0-100% (if the beginning is linear): 5h 33 min.

I get that it may sound horrible, but with my light, efficient use, I’m finishing the day with about 80% after 6 hours of SOT. I needed two full days to drain it to 54% from 100%. So, with a little over 2.5 hours of charging I cover two full days of (light, in terms of usage), use. There is zero chance I need a top-up after charging in the morning (if I end the day above 80%) or overnight (if I end the day below 80% and can therefore trigger optimised charging). So even this speed is faster than what I need.

I don’t think that too many Pro Max or Plus users need a middle of the day 5 hour charge. These phones don’t die at noon, at least not on original iOS versions. I pretty much never drain it to 0% because I like to start the day with 100%. Worst case scenario? A heavy camera day and I may finish with 50-60%. An overly heavy day? 40%, maybe, if that.

5w charging is too fast for me.
 
haha at that point a replacement battery would be cheaper. A $12 fan on amazon should be fine.
Not only that but it would be very ironic if this causes more harm than good. And that's very possible, you may be cooling only part of the battery and create stark temperature differences within the battery. Temperature differences across different areas of it are very bad for the battery, probably worse than not cooling it at all.
 
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Not only that but it would be very ironic if this causes more harm than good. And that's very possible, you may be cooling only part of the battery and create stark temperature differences within the battery. Temperature differences across different areas of it are very bad for the battery, probably worse than not cooling it at all.
putting iPhone in the fridge with the charging cable plugged in would have uniform temperature distribution and no heating as well.
 
My iPhone goes on my MagSafe charging stand when I go to bed at night and comes off in the morning when I get up. My iPhone is in always on standby mode as I use it as my nightstand clock. I don’t waste time worrying about the battery.
 
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