Why fast charger does not shorten the charging time？

24/10/2020

Before answering this question, you must know how does wireless charger work?
Wireless charging works by transferring energy from the charger to a receiver in the back of the phone via electromagnetic induction. The charger uses an induction coil to create an alternating electromagnetic field, which the receiver coil in the phone converts back into electricity to be fed into the battery.
The simple description is: Power to coil in charger is converted to magnetic waves, coil in phone received the magnetic waves, then converted to power to battery of phone.

There are several output powers for wireless chargers today, most of product are 5W, 10W, and 15W. And 10W and 15W belong to fast charge.
Many people will find that using fast charger does not shorten the charging time. There are reason as the following :
1. To use fast charging and wireless charging, you must match the fast charging charger + fast charging cable. Only in this way can the wireless charging receive enough power to output high power.
2. The center of the coil is not aligned. The user needs to know where the coil of his mobile phone is, and then align the position of the mobile phone coil at the center of the wireless charger. This ensures that the electromagnetic waves of the greatest amplitude can be received. Only after receiving enough power can it be converted into a large enough current. Thus shortening the charging time.
3. The mobile phone is too far away from the wireless charging. The solution is to change to a thinner phone case or not use it. Do not place other things between the phone case and the phone.