Ozzie1910 wrote:
Am sorry but that is wrong, using a 30 or 60W power adapter to charge iPhones is not recommended because you can FRY the battery very soon, like an apple advisor told me on the phone, you can not use those MacBook charger to charge iPhones batteries because you will kill the the battery health very soon and run risk that the battery gets swollen and overheating too. period
Some "Apple advisors" can say stupid things, and that's one of them. I have an engineering background, and frankly they have zero idea what they're talking about if they claim that it will overpower an iPhone. It's strictly a voltage source. It may be current-limited, but the iPhone will control how much current draw there is. They likely have no idea what a voltage source really is, or how a USB Power Delivery device negotiates the voltage requirement. And worst case is that it's stuck at 5V, which is perfectly safe for an iPhone no matter how much current it could theoretically put out.
If too much **available** power was an issue, the 2.1A/5V power adapter I've got with an input of 0.5A would be destroyed by my outlet that's rated at 15A. But that's not how it works. It doesn't force electricity in. The impedance of the device controls the maximum current. Voltage = Current x Resistance. Or Current = Voltage / Resistance. The power management system controls the amount of current that it can take and has a limit.
Apple says it's fine, but some people working for Apple may have heard something incorrect.
Fast charge your iPhone - Apple Support
Fast charge your iPhone
Use fast charge with certain iPhone models. You can recharge your iPhone up to 50 percent battery in around 30 minutes.
You can fast charge your iPhone 8 and later up to 50 percent battery in around 30 minutes.
Fast charging works when you use an Apple USB-C to Lightning cable and one of these adapters:Apple *18W, 20W,2 29W, 30W, 61W, 87W, or 96W USB-C Power Adapter
*A comparable third-party USB-C power adapter that supports USB Power Delivery (USB-PD)
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2. You need a 20W or higher power adapter to fast charge your iPhone 12.