I sometimes plug the charger on my iPhone 11 Pro Max and after this, I switch it off. I always can see that when I keep it charging turned off, it takes much more time to charge than when it's turned on. Is it a normal thing? I use the original 18w Fast Charger.
Fast charging is controlled by the phone's software, so I would expect power-on to be necessary. If you power-off during charging I would expect the device should stop charging, or shift to a safe minimum default charging current which will not allow the battery to be overcharged under any circumstances.
Note that an overcharged Lithium Battery can go into thermal runaway and result in an unplanned meeting with your local FireFighters. My advice is to leave the phone powered ON while it charges so the software can safely control charging. If you don't want it disturbing you during charging use the Silent switch or the new Focus function (Used to be Do Not Disturb).
Fast charging is controlled by the phone's software, so I would expect power-on to be necessary. If you power-off during charging I would expect the device should stop charging, or shift to a safe minimum default charging current which will not allow the battery to be overcharged under any circumstances.
Note that an overcharged Lithium Battery can go into thermal runaway and result in an unplanned meeting with your local FireFighters. My advice is to leave the phone powered ON while it charges so the software can safely control charging. If you don't want it disturbing you during charging use the Silent switch or the new Focus function (Used to be Do Not Disturb).
Furthermore a lot of housekeeping including iCloud backup and Photos curation happens overnight, on charge, on wi-Fi and needs to be powered on.
The only reason to turn a phone off is if it glitches. or you are in church.
Charge all night every night and schedule Do Not Disturb.
Does the iPhone support fast charge while it is turned off?
