Shenzhen Keliway Technology.,Ltd

Telephone:

+86-152-19486699

Knowledge
Home > Knowledge > Content

Do you really understand wireless charging?

Edit:Shenzhen Keliway Technology.,LtdUpDate:Oct 11, 2018

Since Apple released the iphone8, iPhone8p and iPhoneX that support wireless charging in September 2017, the concept of wireless charging has been well known since then, but most people don't understand wireless charging, and the concept of wireless charging is very slow. As the iPhone is about to release a new mobile phone that supports wireless charging, Xiaobian talks about all aspects of wireless charging.


Q: Is wireless charging slow?

A: For wired charging, the charging time is related to the size of the charging power and the charging mechanism of the mobile phone. Take the iPhone 8 Plus as an example. Under the same temperature environment, Apple's standard 5V/1A power adapter has a charging power of 5W and a fully charged time of 178min. The iPhone 8 Plus supports 15W fast charging and is charged by the official 29W charger. At the time, the stable power is around 15W and the charging time is 150min. Even if the charging power is increased by three times, the improvement of the charging time for the full charge is not obvious. The reason for this phenomenon lies in the charging mechanism control of the mobile phone itself: when the charging power is large, the mobile phone battery is severely heated and the temperature rise is higher. At this time, the mobile phone will control the power adapter to reduce the charging power, so the significance of the increase of the charging power is to charge more power in a short time, after all, in the user's non-sleeping use scenario, there is rarely a complete full time.

For wireless charging, the charging efficiency is also involved. The charging efficiency refers to the overall efficiency of the receiving end and the transmitting end. If the transmitter and the receiver are separated, the general transmitter efficiency is about 80%, and the receiver efficiency is 90%. Around, the overall efficiency is about 70%. Taking the 10W transmitter as an example, the actual wireless charging power is 7W, so that the charging time of the iPhone 8 Plus is fully charged is 210min, but the charging amount in the 40min charging time is equivalent to the standard 5W Apple adapter. Vodafone's latest 15W wireless transmitter solution with WPC1.2.4 EPP certification, the actual wireless charging power is 11W, which will make the charging speed in a short time much faster than the standard 5W Apple adapter.

3 in 1 wireless charger.jpg

Compared with the charging speed of the wired charging, the charging of the cable is not stable because the receiving coil generates heat inside the mobile phone. As the heat dissipation performance of the coil and the charging efficiency of the transmitting end and the receiving end increase, the charging speed will become faster and faster.


Q: Is wireless charging safe?

A: WPC, the wireless charging alliance, was established on December 17, 2008. The Qi standard developed by the alliance aims to achieve interoperability between various charging boards and portable devices. Apple, Samsung and other brands are all alliances. Members, Apple, Samsung's mobile phones are also in line with the Qi standard. Products that are certified by the WPC Alliance will be marked with the word "Qi", a terminal with "Qi", which can be charged on all charging boards marked with the LOGO.

The latest WPC 1.2.4 EPP clarifies the temperature rise requirements for wireless charging, and proposes various detection methods such as ping phase Q value detection and power transmission phase correction power loss calculation for foreign objects, which greatly improves the security of wireless charging. Therefore, the security of wireless charging products with the word "Qi" is clearly guaranteed. Vodafone's wireless charging transmitter solutions are WPC-certified, with the 15W solution being the world's most integrated 15W transmitter solution certified by WPC1.2.4 EPP.


Q: Is the wireless charging distance short?

A:·The distance of wireless charging (degree of freedom) refers to the distance between the center of the mobile phone and the center of the wireless charger as the origin, the distance of the mobile phone from the origin, and the degree of freedom is divided into the degree of freedom of effective ping and the effective charging. Degree of freedom. Effective ping means that the mobile phone can be placed in the wireless charger to enter the wireless charging. The effective charging refers to the mobile phone to enter the wireless charging and the mobile phone does not lose power. Vodafone's wireless charging transmitter solution has an effective ping freedom of up to 8mm, and the effective charging degree can reach 15mm. After the size of the wireless charger is properly designed, it can be fully charged.


Q: Is wireless charging not popular?

A: Apple is the leader in the mobile phone industry. Since the mobile phone supports wireless charging, most mobile phone brands have launched or are about to launch mobile phones that support wireless charging.