Charging time

The 5W charger is the slowest charger out there. You also have Optimized Battery Charging set to ON. This means that your iPhone will take up to 2 hours or more to get to 80% and then the Optimized Battery Charging feature will slow it down even further to get to 100%. This is determined based on your usage and charge times history. Yes, 4 hours to reach from 0% to 100% is absolutely possible.

If you want to conduct another experiment then turn OFF Optimized Battery Charging and begin charging the phone once it drops below 30%. See the speed to get to 100% has been improved.

Axel F.

That depends on several conditions.

1. Which charger are you using?
2. What is the charger’s wattage rating?
3. Is Optimized Battery Charging set to ON?
4. Is it taking 4 hours to charge from 0% to 100%?

Axel F.