[Q] Qi Charging Pad that has auto shuts off

Hello xda,

I am looking for a charging pad that auto shuts off when my Note 4 is full. It is hard to find those kinds of wireless chargers. I am using a Qi-Infinity charging receiver as it is the only one I found that retains NFC functionality. But first, a story.

I went through 2 charging receivers because both does not retain NFC functionality. I ended up with the Qi-Infinity as my third and final charging receiver.
I have a RAVPower Charging Pad (RP-WCN7) which seems to continually charge my Note 4 even when full.
So, for the interesting part.
I bought another receiver from amazon that says it will stop charging when the phone is fully charged.
Sure enough, it didn't do that for my Note 4. But interestingly, it stopped charging when I tested it out with a Nexus 4.

Am I missing something with wireless charging technology? Is there a protocol that the qi standard uses to send out charge status? If someone could suggest a wireless charger that shuts off automatically, that would be great! :D

Thanks