Super Fast Charging being slow

[ConorDavies]

Hello, I got the S21 Ultra a few days ago and have been charging it with the standard "cable charge". I got the 45W Super Fast Charger today, plugged it in and to my surprise the charging speed hasn't improved. At 90% with the cable charge it says it would take 30 minutes to charge the last 10%, when plugging in the Super Fast Charger it's exactly the same, 30 minutes just to do 10%, why is it doing this?

And yes "Super Fast Charging" appears when I plug in the new charger. 

[xSteveuk]

Hi,

Help page
Scroll down page
Will give info on 45w charges

https://www.samsung.com/uk/support/mobile-devices/how-to-use-and-charge-galaxy-s21-series/

[Mimo40]

Wrong charger you need the 25watt charger to get superfast charging

[ConorDavies]

I'm getting Super Fast Charging, when I plug it in it literally says "Super Fast Charging". And besides, I just used my brothers 25W charger and I am getting the exact same charging speeds as both the "Cable Charge" and the 45W charge. So, it's not that.

[Mimo40]

Hi first up the from Reading off the Internet the s21 does not support 45watt charging like the s20 people say it could damage the battery like what happened to the note 7 so you will only get the same charging speed as a 25watt charger

[ConorDavies]

I see, so what do I do then? Do I need to stop using the 45W charger to prevent damaging the phone? And just to explain in case there is some confusion.

I'm getting the exact same charging speeds when using a 15w charger and a 25w charger. There is no difference for me.

[Mimo40]

For me I would use the 25watt charger just for the safe side of things. Give it time for battery to settle down then to test it I would turn phone off and one day charge it with 25watt charger time it then same again with the 15watt then compare what is the fastest.

[Mishal]

For my device, i can clearly see the difference between Fast Charge and Super Fast Charge. You can get Super Fast Charge only with the official 25W charger. With any high Powered Charger, you will only get Fast Charging. See the screenshots of official 25W Charger(Superfast Charging) and my Macbook Charger(Fast Charging) and from Macbook(Charging). You can see the difference in remaining time to full charge. But as you said if your device displays Superfast Charge but still displays the same remaining time as Fast Charge or Cable Charge then may be your device is having technical issues.

[xSteveuk]

Super fast charging and apps running in the background heat the phone.

So the phone stops or slows down the charging until it cools back down and goes back to super fast charging.

[John19691969]

All S21 series do not use 45w charging ...25w max even if you use the 45w charger will only charge phone at max 25w S20 ultra does 45w charging and few others but all the s21 phones are set to max 25w charging . Will say super fast charging 2.0 when it's 45w ..so no point buying the 45w charger for S21 , S21 plus or S21 ultra because you will only get 25w charging from them not 45w