How does wireless charging work?

You’ve probably heard something about wireless charging already. More and more devices have come out which support this technology and allow you to charge your phone without cables.

You will probably also have heard terms such as Qi, induction and wireless coils. This article will explain what Wireless Charging exactly is.

 
 

Often heard terms

Let’s start by shortly explaining some terms to take away the confusion about wireless charging, or induction charging.


 
 

Induction Charging

This is the physical principle upon which wireless charging is based. When someone speaks about wireless charging, they are automatically also speaking about induction charging.
 

Qi Charging

This is a standard for wireless (or induction) charging which has been developed by a consortium of large companies, universities and other parties, including almost all major phone companies such as Samsung, LG and many others. It has become the dominant standard for wireless, or inductive, charging, which almost all devices these days use.
 

Wireless Coil or Patch

The working of inductive charging depends on two wired coils (how this works will be explained below) which transfer power to each other. Both the charging device (E.g. power bank) and the charged device (E.g. phone) must have such a coil to allow wireless charging.
 
 

How does it work?

Without delving into the exact physical explanations: when electricity ‘travels’ through a copper wire, it provides an electromagnetic field. The inductive coil used for wireless charging has a special placement of copper wires to create a specific magnetic field.

The magnetic field which is created by the sending coil (E.g. charging station) interacts with the receiving coil. In turn this magnetic field is turned into power by the receiving coil and then transferred to the device (E.g. mobile phone).

 

In other words: Electricity → sender coil → magnetic field → receiving coil → electricity.