A:Answer The pad. Lower power wall adapters produce slower charging speeds or, in some cases, don’t power the pad at all.
The Qi (chee) 1.2 standard supports charging speeds of up to 15 watts (9 volts, 1.67 amps), but 7.5 W and 10 W chargers are more common right now. iPhones can charge at speeds of up to 7.5 W via regular Qi charging or 15 W with an Apple-certified MagSafe Charger. Many Android phones can do up to 10 W, and some even support 15 W charging (Samsung series 20 and above). 5W chargers are slower.
Long story short, you need to know your phones capability to charge (iPhone 7.5 to 15W and Android 10 to 15W).
You also need to know the pads capability to charge (i.e. 5 to 15W).
And if buying a pad without an included cord/plug, make sure you are providing a cord/plug that provides the juice necessary to power the pad at the level it can handle.
I would not try to "overpower" a pad, unless it utilizes technology that limits overpowering.
My 2 cents.
