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stpfun t1_jdtg4s7 wrote

You can hook your iPhone up to a 240W USB-C PD charger no problem. I charge my iPhone off my 96W MBP charger all the time.

What happens though is the phone only pulls the current it can use. With the latest iPhones that’s about 20W or about 2.22 amps @ 9 volts. (And it can only pull that much when the battery is low, not when it’s nearly full).

Just looked up the upcoming 240W Realme phone and wow, that’s insane. It does sound like it can only pull and make use of the full 240W when the battery is nearly empty. But it goes from 0% to 20% in 80 seconds which is just insane. I highly suspect they had to sacrifice energy density, and total battery capacity/run time, to get a battery that can do this. Though with charging that fast I’d just hook it up for a couple mins before I leave the bough and I’d be good to go.

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ONE_BIG_LOAD t1_jdu0p30 wrote

my OnePlus 8t charges at 65W meaning 0-100 in about 35 minutes. It's freaking amazing and I'm sad I won't be buying OnePlus again since the fast charging has spoiled me.

As for battery run time etc... 2 years of fast charging to 100% almost every day later and I am at approximately 85% battery health and still getting 4-5 hours of screen on time with heavy usage. It's a 4500mah battery

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stpfun t1_jdwwug5 wrote

That's rad! I'm sure it can use that full 65W when the battery is low. Though I'm pretty sure it can't use the full 65W of charging power the entire time it's charging. LiPo battery chemistry just doesn't allow it.

It's also easy to show this with math. According to the internet the OnePlus 8t has a 17.02 watt-hour battery. As in it stores enough energy to output 17.02 watts for 1 hour. (though it probably can't discharge that fast in practice). If a 17Wh battery charged at 65W the whole time it would take 17Wh / 65W = 15.69 minutes to charge! But because it takes 35 minutes, we know it must charge at 17 Wh / 35 minutes = 29.14 watts on average. Which is still craazzy fast. The latest iPhones, which can charge at 20W peak, but have an average more in the range of 12W.

I got into this stuff just by playing around with a USB-C power meter like this one. With that plugged into my charging cable I can finally actually see how many watts my devices are pulling at any given moment.

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ONE_BIG_LOAD t1_jdwxe07 wrote

Woah that's cool stuff. I have an app on my phone that tells my current charging stats so I'll let my phone drop down to 5% or so today and see how many watts it's pulling.

At lower battery it really is fast I can leave it on for 5-10 minutes and be back upto 50% after that it starts to charge a bit slower.

BTW I've never owned an iPhone but I like to stay educated... How long do the latest iPhones take to charge? 10W sounds like nothing but I also believe iPhones have significantly smaller batteries/better optimization than Androids.

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stpfun t1_je13dpj wrote

in my experience iPhones take ~90 minutes to fully charge, but similarly to your experience they charge up to the first 50% much faster with a faster charger, though more like 30 minutes instead of 5-10. (I'm jealous!)

And you're right that it seems like they have smaller batteries! Like my non-large iPhone 14 pro has a 12.38Wh battery but it lasts all day easily. Never thought about it before but this must mean that Apple's chips/software just pull less energy. (also I was wrong before, if a 12.38Wh battery takes 90 minutes to fully charge then it's average charging rate is only 8W, even lower than the 10W-12W I guessed!)

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