Wireless Charging

Wireless charging moves power from a charging pad to a device without a cable connecting the two. Most devices use a method called inductive charging.

How it works

The pad has a coil that carries alternating current, which creates a changing magnetic field. A matching coil inside the device picks up that field and turns it back into electric current, which charges the battery. The coils must sit close together and line up well. Some systems add magnets to hold the device in the right place.

Qi and magnetic versions

Qi is the common open standard made by the Wireless Power Consortium, so pads and devices from different brands can work together. Newer versions of the standard add magnetic alignment and support higher power levels. Some brands also use their own faster systems that work only with their own chargers.

What the numbers mean

The watt figure shows the highest power the system can send. Wireless charging loses some power as heat, so the battery receives less than the pad draws from the wall.

What it does not promise

Wireless charging is usually slower than a good wired charger. It does not work over a long distance, and a thick case, a metal plate or a misaligned device can slow it down or stop it. A device supports only the power level its own hardware is built for, whatever the pad can deliver.