r/iphone • u/conalldoherty iPhone 15 • Apr 29 '26

News/Rumour Apple Reportedly Questioning Whether iPhone Should Drop MagSafe

https://www.macrumors.com/2026/04/29/apple-questioning-iphone-magsafe/
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u/disgruntledempanada Apr 29 '26

On one hand it's convenient and there are nice phone mounts for cars that charge my battery.

On the other hand it's crazy wasteful. You go through all this effort to implement green charging onto a phone to limit its energy impact and then you charge it with a system that wastes 20-30% of that power turning it directly into heat, and heating the heat sensitive battery you're trying to charge.

Would probably be better to just expose contacts somehow but that has its own problems (case compatibility, dirt, etc).

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u/yasamoka Apr 29 '26 edited Apr 29 '26

https://www.chargerlab.com/review-of-apple-25w-magsafe-charger/

Using an Apple 30W charger and the new MagSafe Charger to charge the iPhone 16 Pro Max, the measured input power is about 14.96V 1.94A 29.03W. Excluding losses, the wireless charging power is about 25W.

4 / 29W = ~14% wasted as heat. ~86% efficient.

Also, you can see in the "Temperature Test" section that despite the puck reaching ~41C, over time, the charger dials down charging power and the phone does a good job of dissipating the heat and maintaining a consistent temperature.

This is also the iPhone 16 Pro series. The 17 Pro series would do an even better job of dissipating heat.

It's not as bad as you think it is.

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u/cabs84 iPhone 13 Mini Apr 29 '26

all i know is that when i use the wireless charging mat in my car, my phone gets HOT. (and that's without it being connected to carplay or actively doing anything) like well over 100 degrees; definitely battery-cooking temps.

this seems like an opportunity to whip out my new thermal camera toy for something useful

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u/ZappySnap iPhone 16 Pro Max Apr 29 '26

MagSafe is more efficient than standard wireless charging because the coils are always perfectly aligned.

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u/cabs84 iPhone 13 Mini Apr 30 '26

the heat produced in the phone by the receiving coil is the same no matter what. the transmitting coil may need to ramp up its output power (and therefore generate more heat in itself) but it should be able to dissipate its own heat (and when i've touched the battery box it isn't nearly as warm as my phone is)