Review on Taidacent 12V 2A High Power Wireless Charging Mat Module - DIY Inductive Modules Charger Kit with Technical Support by Jermaine Batista

Basic initial testing shows it's working at least. 24V input gives about 12V output. The voltage will drop slightly depending on the distance (too close or too far, or if the coils are more than 25% offset). I tested it briefly with a 0.4A load at 12V and a distance of 8mm, and the transmitter coil drew 0.3A at 24V (65% efficiency) with no noticeable component overheating. With no receiver coil installed, it drew 0.07A (24V). There is a potentiometer that allows finer control of the output current, but if the coils are misaligned or have sub-optimal spacing it will not allow the voltage to rise back to 12V if the coils are 8mm or closer, it will damage the components. As a star was deducted due to the design of the boards, it would be impractical to mount the boards on or in a case.