Current AirPods can only be charged with a Qi-compliant charging pad if they're in the appropriate case. By appropriate case I mean Apple has launched a new optional charging case that supports wireless charging for AirPods.
You may wish to read:
Apple revealed a new AirPods case that works with Apple's new AirPower charging pad. To charge the new wireless case, you place it
on the AirPower. If your AirPods are in the case, you’ll see an orange
light if they’re charging, or a green light when they’re nearly fully
charged. If no AirPods are in the case, the light still goes on when
you open the lid, but it indicates how much battery life is left in
the case itself: orange for needs charging and green for good life
As of this writing, Apple has not released pricing for the new
wireless case, nor has the company said that it will replace the
original case with the new one with a new pair of AirPods. The
wireless case will be available in 2018.
Source: See second link above