Some time ago, Xiaomi released its own air charging technology with a power of 5W. As you can see from Xiaomi’s promotional video, this technology is indeed very sci-fi, but it may not be used in China.
Just today, the Ministry of Industry and Information Technology stated in Article 4 of the "Interim Regulations on Radio Management of Wireless Charging (Power Transmission) Equipment (Draft for Comments)" that the rated transmission power of mobile and portable wireless charging equipment does not exceed 50W. . Mi fans find it strange that the air-to-air charging shown by Xiaomi is only 5W, so why can’t it be used?
It turns out that Xiaomi’s air charging is achieved through millimeter waves, and the frequency band of millimeter waves is between 30GHz and 300GHz.
In the draft for comments from the Ministry of Industry and Information Technology, in addition to stipulating that the rated transmission power of mobile and portable wireless charging equipment does not exceed 50W, it also stipulates that the frequency bands should be between 100-148.5kHz, 6765-6795kHz, and 13553-13567kHz. , obviously these frequency bands do not include millimeter waves. In other words, if the consultation draft is finalized, the air-to-air charging demonstrated by Xiaomi will not be able to meet domestic standards and will not be usable.
Coincidentally, Xiaomi is already selling 55w wireless fast charging, and there are also reports that Xiaomi 11pro will be equipped with about 67w wireless fast charging, and even the laboratory requires 80w wireless fast charging, but these have exceeded the solicitation. With the 50w specification in the opinion draft, these technologies may be in vain in the end.
In addition to Xiaomi, OPPO, which has been deeply involved in the field of fast charging for many years, also released its own 65w wireless fast charging in July last year, which also did not meet the power limit in the draft for comments.
As for why such regulations appeared, the Ministry of Industry and Information Technology said: This is to regulate the orderly use of radio spectrum resources by wireless charging (power transmission) equipment, avoid harmful interference to various radio services carried out in accordance with the law, and maintain Airwave order.
I personally feel that the use of radio frequency resources does need to be more rational and orderly, otherwise it may cause interference to radio signals and have adverse effects. If the final indicators can be implemented, the wireless charging "race" for mobile phones will also come to an end, because many mobile phone manufacturers now have wireless fast charging technology that can reach 50W.
As for the future technology of air charging, Xiaomi millimeter wave does not seem to be a good solution at present. In addition, in Huawei's patent information, it was found that Huawei applied for a patent for using long-distance lasers to achieve air charging in 2019, which may become one of the ways to achieve air charging in the future.