Search Phones with Wireless Charging

Wireless mobile charging is a function that allows you to charge your mobile phone without plugging in cables. However, the charger on which you put the phone must have plugged in a cable. Below you will find all the advantages and disadvantages of wireless charging as well as some techniques and a piece of history.

Advance wireless charging

The overwhelming advantage of wireless charging is that you no longer need to plug a cable into your phone to charge it. Instead, put it on the charger. That's handy in the dark where you don't have light to find the charging port. It also keeps your mobile longer because plugging in the connector each time can damage your device. In theory it might even be possible to make a completely port-free phone where no dust, dirt or water can penetrate.

Charge wirelessly

Wireless charging also has disadvantages. For example, wireless charging is slower than wired charging. Energy is also lost in the charging process, making it slightly less efficient and therefore more expensive to use. A number of these drawbacks have largely been addressed in recent years. Nowadays you have wireless fast chargers and thanks to newer techniques the loss of energy has been minimized. Another drawback is that the phone must be close to the wireless charger. They prefer to touch each other. So it is not possible to charge your phone from one side of the room.

Standards

Just like charging cables, there are different standards for wireless chargers. For mobile phones and other consumer electronics there are currently two important ones;

• Qi
• PMA

The best known is Qi (pronounce as sjie). This technique has been developed by the Wireless Power Consortium (WPC). Most phones that can be charged wirelessly support this standard, think of Apple and Samsung. The other standard is PMA which stands for Power Matters Alliance. Although that organisation merged with the Alliance for Wireless Power (A4WP) in the AirFuel Allliance in 2015, the PMA name has stuck. The two standards work virtually the same; via induction. To make it easy for manufacturers, most mobile phones support both Qi and PMA. Before you buy a wireless charger, make sure your mobile really supports it; they're not fully compatible.

Current phone wireless charging

If your current mobile phone does not support wireless charging, there is still a way to charge it wirelessly. Through a case. Some popular models that did not come out with wireless charging have such cases. In Google, enter the name of your phone followed by "wireless charging case". Nowadays we see that manufacturers now equip their expensive flagships with wireless charging as standard.

Reverse wireless charging

A relatively new feature in the world of wireless charging is reverse wireless charging. Here it is possible to charge another device instead of your phone. This is because the process of wireless charging can be easily reversed. Your mobile gives away the energy instead of receiving it. For example, put your AirPods on your mobile to charge them. You can also give power away to other phones by putting them against each other. Not every phone with wireless charging supports this function. So that's something to watch out for when you're specifically looking for this.

Wireless fast charging

Wireless charging is slower than cable charging. Methods have been devised to alleviate this problem. Wireless quick chargers can be recognized by the fact that they have more than 5 Watts as output. Fast 10 Watt chargers roughly halve the charging time. However, if you want to be on the road again in 15 minutes or less, you can't escape the wired quick chargers.

Operation

Wireless charging works on the basis of resonant induction. In the phone there is a coil; a wrap of copper wire. This captures a magnetic field and converts it into current to charge the battery. The magnetic field is in turn generated by running current through a coil. The wireless charger usually contains several of these coils to increase the surface area on which to charge. This principle only works if the transmitter and receiver are reasonably close to each other (maximum 4 centimeters) and not interrupted. This is the reason why cordless rechargeable phones do not have a metal back but glass or plastic.

There are other ways to transmit power wirelessly. Think of ordinary induction (toothbrush and kettle), capacitive charging (smartcards), dynamic charging (electric cars), microwaves (satellites) and light waves.

History of wireless charging

Already in 1831 the principle of wireless power transmission was discovered. However, there was a lack of resources to put this into practice. It was Nikola Tesla who carried out the first experiments with wireless current between 1890 and 1906. However, it never turned out to be a truly marketable product. Meanwhile, discoveries and experiments in the field of induction continued. The need for wireless charging became evident for consumer electronics in wet areas such as the bathroom.

Also mobile phones turned out to be very suitable for wireless charging, especially because they need to be charged so often and messing around with cables is annoying. The Wireless Power Consortium was founded in 2008. The aim was to create a standard that every manufacturer would adhere to. This was Qi that came out in August 2009. It was Palm who had the honour to announce the first mobile with wireless charging; the Palm Pre. Other manufacturers will follow years later. Nokia released the Lumia 920 in 2012 while Samsung did not release its first mobile until 2016; the Galaxy S6. Nowadays, as a manufacturer, you no longer belong if at least your flagship is not equipped with wireless charging.