How Does Wireless Charger Work?

Wireless charging is becoming more and more popular because of apple's iPhone 8, iPhone 8 Plus and iPhone x use Qi wireless charging technology.Wireless charging can also be seen on some android phones, such as samsung's Galaxy Note 8, Galaxy S8 and Galaxy S7.

Most wireless chargers are based on magnetic induction and magnetic resonance.They offer a charging scheme for putting devices on a surface that can be recharged without needing a cable.

The principle of wireless charging

Of course, wireless charging is not really wireless charging.Although say, your mobile phone, smart watches, tablet, wireless headset or other devices don't need a wire connected to the charger, but wireless charger itself also need to be plugged into a wall outlet to work properly.When the iPhone 5 was released, the android camp had mobile phones equipped with wireless charging.Phil Schiller, an executive at apple, did not agree. "in most cases, it's more complicated to develop another device."

Five years later, apple changed its mind.With the support of the iPhone 8, iPhone 8 Plus and iPhone X, apple supports the use of Qi open standard wireless charging.

Wireless chargers usually use magnetic induction.The simple explanation is that they use magnetism to deliver energy.First, you put the device, like a smartphone, on a wireless charger.The current from the power outlet passes through the wires of the wireless charger, creating a magnetic field.The magnetic field generates an electric current in the coil of the wireless charger.This magnetism can be converted to electricity and used to charge the battery.Devices must have the right hardware to support wireless charging, and devices without wireless charging coils cannot be charged wirelessly.

Although the Qi standard was originally limited to magnetic induction, it now supports magnetic resonance.The device works like this, but it can be about 45 millimeters away from the surface of the wireless charger, rather than touching it directly.This method is less efficient than magnetic induction, but it has some advantages - for example, a wireless charger can be mounted on the surface of a table and you can charge a device on a table.It also allows you to put multiple devices on a charging board and to charge all devices simultaneously.

The Qi charger does not consume the most power when it does not charge.Instead, it USES less power, and when it detects that the device is placed on the charger, it increases the energy output.

Standard competition: Qi vs Powermat vs Rezence

Wireless charging is becoming more common and even more standardized.This time, apple didn't create its own wireless standards.Instead, it chooses to support existing Qi standards, and many other devices support it.

However, Qi is not the only standard.The wireless power alliance has a lead in Qi, but it is not the only standard.Second in the list is Powermat, the Power affairs alliance, or PMA.Like Qi, it USES magnetic induction.But they are incompatible.The iPhone can't be charged with a PMA wireless charger.

However, some devices are compatible with both devices.Modern samsung devices, such as the samsung Galaxy Note 8, Galaxy S8 and Galaxy S7, actually support Qi and PMA standards and can charge simultaneously.Starbucks is betting on PMA, but they may reconsider the idea that the iPhone only supports Qi.Apple is betting that airports, hotels and other public places will also bet on Qi.

Rezence of the wireless power supply alliance (A4WP) used magnetic resonance, and later added the Qi function.This makes positioning more free.You can install multiple devices on a charger, move the device, and even put a book between the device and the charger to recharge the device.Rezence asked to use bluetooth to communicate with the device.

The second and third companies, PMA and A4WP, have been renamed AirFuel Alliance and are trying to work with Qi.

How to use wireless charging

If you want wireless charging, you'll need a smart phone that supports wireless charging and a compatible wireless charging pad to place your phone.You can also buy adapters to add wireless charging support to phones without wireless charging technology.

Popular smart phones that support wireless charging include:

Apple's iPhone 8, iPhone 8 Plus, iPhone X

Samsung Note 8, Note 5, S8, S8+, S8 Active, S7, S7 Edge, S7 Active

LG G6 (U.S. and Canadian edition), V30

MOTOROLA Moto Z, Moto Z Play, Moto Z2 Force, Moto Z2 Play (just wireless charging module)

In recent years, android phone makers are abandoning wireless charging technology.Only samsung has maintained this feature on its most recent high-end phones.Google, for example, does not offer wireless charging on the Pixel smartphone, but earlier Nexus phones also included this feature.Given apple's vote of confidence in Qi, wireless charging is likely to become more common on Android devices.

If your phone doesn't support wireless charging, you can increase your wireless charging support by using a special phone shell or a wireless charging adapter.

Once you have a mobile phone or adapter that supports wireless charging, pick up a compatible wireless charger.For most phones, you need an Qi charger.Any Qi authentication wireless charger should be compatible with any Qi authentication device.As long as your device and charger support the same standard, it will work.

In the future, wireless chargers are more common in public places, and you just need to charge your smartphone on the table.