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macrumors newbie
Original poster
May 14, 2018
Hello everyone,

I have an iPhone 12 PM and replaced my battery recently.

I want to protect my new battery and I bought the old 5 watt adapter

My concern is that from a specific apple authorized service told me that they don’t suggest the 5 watt adapter because can reduce battery health for new iPhones.
From another service they told me that the only thing changed is the time of charging.

Can someone help me please ?
Is it better to use the classic old 5 watt adapter ?

Thank you!!


macrumors 6502a
May 28, 2011
I’ve had battery health issues in the past with my 12 pro and 13 pro. I started using the 5w charger and it didn’t make a huge difference in my personal experience. Just make sure to charge your phone when it’s below 80% and above 20%. Don’t let your phone get too hot or even too cold.


macrumors newbie
Jul 26, 2023
Hi. Until recently, I used a 5-watt adapter myself, I thought that this way I would save myself battery power. And then I wanted to charge my iPhone much faster and purchased a 20 watt adapter and was completely satisfied. The iPhone charges many times faster, the main thing, as ipadlover29 said, is to monitor the heating of the smartphone during charging. And you can safely use a 20-watt adapter.


Aug 17, 2023
Will the 5W wall charger finish to 100% in less than 8hrs? I'd only use that before I sleep.

I'd use a 30W car charger to get 0-50% within 30 mins drive.

If you have any Macbook Air I'd get this 100W multiport charger.

Using a USB-A lighting cable the iPhone can only draw up to 10W.

Using a USB-C lighting cable the iPhone can only draw up to 30W.

Last edited:


macrumors demi-goddess
Sep 22, 2015
Washington, DC
I’ve been using a 5w brick with every iPhone. It didn’t matter what brick I used with my 12PM as it stayed on iOS 14.1 and it still degraded to 84% in two years with Optimized Charging turned on.
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