Qi (pronounced/ CHEE from the Chinese word qi) is an open interface standard that defines wireless power transfer using inductive charging over distances of up to 4 cm (1.6 inches), developed by the Wireless Power Consortium. The system uses a charging pad and a compatible device, which is placed on top of the pad, charging via resonant inductive coupling.

Version 1.0 - 2010 up to 5 Watt
Version 1.1 - 2012 up to 5 Watt
Version 1.2 - 2015 up to 15 Watt