Wireless charging source to radio transmission technology, low power wireless charging often uses electromagnetic induction type (such as mobile phone charging of Qi), high power wireless charging often uses the resonant energy in the magnetic field, because the transfer between the charger and electric devices, not between wires, so the charger and electric device can do without conductive contact exposed.
There are four kinds of mainstream wireless charging standards: Qi standard, PMA standard, A4WP standard, iNPOFi technology. Among them, Qi is the first standardized organization to promote wireless charging technology in the world, the wireless charging standard launched by WPC. It has two characteristics: convenience and versatility. First of all, different brands of products, as long as there is a Qi logo, can be recharged with Qi wireless charger. Secondly, it conquers the technical bottleneck of the universality of wireless charging. In the near future, products such as mobile phones, cameras, computers and so on can be charged with Qi wireless charger, providing a possibility for large-scale applications of wireless charging.
The mainstream wireless charging technology in the market is mainly through three ways, namely electromagnetic induction, radio wave and resonance, and Qi adopts the most mainstream electromagnetic induction technology. In terms of technology applications, Chinese companies have already stood at the forefront of the wireless charging industry. It is reported that the main applications of Qi in China are mobile phones and portable digital products.