How Wireless Charging Works?

by Shubham Khurana

Do you also have this one drawer that is completely full of cables? Half of them are charging cables, suitable for your current smartphone, your old smartphone, your partner, and some are used for old iPods, fitness bracelets, etc. And do not forget that each device has not only one cable, but also several because you always like to lay them. 

To put an end to this clutter of cables, you want to switch to wireless charging. But how easy is it? How does this technology work? Is it really just a bonus? In this article, we will dive into these issues.


What is Wireless Charging?

Wireless, i.e. induction charging, has been around for some time. If you have an electric toothbrush or induction stove at home, you often use this technology. It is slowly gaining a foothold in the smartphone market, and flagship products such as the iPhone 8 or Samsung's latest Galaxy models have integrated this technology. Therefore, you no longer have to look for a charging cable for a long time, just put your smartphone on the charging pad, and the battery will charge.


Here's how it works!

The mechanism behind the charging process works via induction: A coil is installed in the charging station through which the alternating current flows. This builds up a magnetic field around the charging plate. The smartphone itself also has a coil. If it enters the magnetic field of the charging station, the current will also flow through the coil of the smartphone and then it will be fed directly to the battery.


This means that the smartphone will only transfer energy when it is too close to the charging pad to enter the magnetic field. Most charging stations also send signals to detect if the smartphone is in the charging station and if it still needs power. This minimizes constant electromagnetic radiation.


Inductive charging used to have three standards: Qi (pronounced: Tschi), Rezence, and Powermat. In the meantime, they all belong to the Wireless Power Consortium (WPC), which promoted the rise of Qi technology.


Advantages and disadvantages of wireless power transmission

One of the main advantages of wireless charging is that its simplicity for users to use. You don't need to search for a data cable and connect it to your smartphone; just place your phone in a suitable charging point to charge the battery. This means that the plug-in contacts of the smartphone or the charger itself are not worn. There are more and more loading cradles offering space for a variety of devices. For example, two or three smartphones can be charged from an outlet that supplies power to a charging point.


Due to the qi technology standard, the user is independent of the manufacturer. Thus, mobile phones from different producers can be charged with the same pad.


Advantages:

  • Easy to use without charging cable, hang up is enough
  • No wear on cable and mobile phone
  • Same standard for different manufacturers
  • Third-party products are standard compatible
  • Charging pad can be integrated into furniture, cars, etc.

The standard only applies to current mobile phones. Older models must be equipped with corresponding adhesive pads or covers. In addition, wireless chargers must be purchased separately; they are not part of the normal scope of delivery. 


The mobile phone must be placed directly on the charging stand when charging. Therefore, it is difficult to use during charging. A charger with a support function can provide a solution here. A thicker protective cover may also cause problems for the charging process. Despite tremendous progress, the charging time of today's wireless devices is generally slower than that of wired devices. The efficiency of inductive energy transmission is also lower, which leads to more energy loss.


Disadvantages:

  • Many devices require retrofitting
  • Charging station is not part of the standard scope of delivery, sometimes expensive
  • Direct contact to charging cradle necessary, difficult to use
  • Depending on the thickness of the protective cover, it must be removed
  • Lower efficiency than a cable connection, longer charging times

How to Use the Technology

If you also want to inductively charge your smartphone, but it does not meet the standard, you can buy special cases. A coil is integrated into this that can absorb the power of the pad and then forward it to the battery via Lightning or USB cable. So this variant is not completely wireless.


If you really want to charge wirelessly, you must have a suitable smartphone. Since the Galaxy S6, the manufacturer Samsung has integrated this technology into its models. Apple has also provided inductive charging for the iPhone 8 and iPhone X. Of course, you need a charging station. They are available from various manufacturers in various shapes, colours, sizes and performance levels.


We would love to know how this technology has developed and how it can make our lives easier. Because not only for my cable drawer but also for total mobility in the future, the issue of wireless charging has become more and more important.