Yes, the Mi 80w wireless charger is compatible with Mi 9. The Mi 9 supports wireless charging up to 20w, while the Mi 80w wireless charger supports wireless charging up to 80w, so charging speed can be significantly improved. However, it should be noted that in order to get the fastest charging speed, it is recommended to use the original charger and data cable that supports fast charging. In addition, when using a wireless charger, the phone needs to be placed in the center of the charger to ensure the best charging effect.
The Mi 9 does not support such a high power charging