Wireless recharge: what is and how it works

Wireless recharge or induction is based on the law of the induction of Faraday (man to the cage) and the law of Ampère (the man who gave his name to the unity of the intensity of the current current electric). A current circulating in a coil generates a magnetic field. We find this coil in the charging station. This magnetic field produces a tension in a second coil, which is in the device itself. This tension makes current circulation possible in this second coil.

How does induction recharge work ?

Induction recharging is not new: it has been used for many years with electric toothbrushes, in order to avoid any risk of electrocution for the user. He is now experiencing beautiful days with digital devices. Induction recharging works without physical connection between the charger and the device, whether it is a mobile phone or a laptop. Such wireless recharging is based on the principle of electrical induction, according to which the circulation of an electric current in a copper coil (wire winding) creates a current in a nearby coil.Concretely, the part “Charger” often takes the form of a flat surface inside which is the first copper coil. When fed by an electric current, it produces a magnetic field (this is the principle of electromagnet). When the device to be recharged is placed on the charger, their proximity is such that the magnetic field created induces an electric current in that of the “Receiver” and feeds her battery.As the device to be recharged does not have an internal electric coil, it must be connected to an external coil so that the energy transfer can be made. This takes the form of a shell in which we insert the phone or a small case that we put on the “Charger”. In both cases, the support is connected to the power supply connector of the device to be recharged, and plays the role of intermediary. However, recently, some manufacturers have been offering replacement batteries for mobile devices in which a coil is already present, which allows you to be freed from the support acting as a receiver

Wireless recharge: what is and how it works ?

Wireless recharge bases for smartphone flourish everywhere: in cafes, integrated into furniture or cars and for sale in electronics and online stores. But how does wireless recharge work ? What devices are concerned ? And what are the advantages and disadvantages of this technology ? You will discover the answers to all these questions in this blog article.

Wireless recharge ? This is not new: this technology has existed for years . For electric toothbrushes !

Wireless recharge is to load the battery of your phone by simply putting it on a charging basis, without current charging cable. Wireless charging technology is based on electromagnetic induction. This is not a novelty: it has existed for years. For electric toothbrushes ! Smartphones manufacturers have experienced wireless recharge since 2009, but technique is really a breakthrough at present.

Wireless recharge, how it works ?

Wireless recharge is possible thanks to electromagnetic induction. Electric energy is transferred from one object to another (for example a charger and a smartphone) via a magnetic field. So you don’t need cable to recharge your device.

You want to hear the whole scientific history ? In this case, continue to read.

Wireless recharge or induction is based on the law of the induction of Faraday (man to the cage) and the law of Ampère (the man who gave his name to the unity of the intensity of the current current electric). A current circulating in a coil generates a magnetic field. We find this coil in the charging station. This magnetic field produces a tension in a second coil, which is in the device itself. This tension makes current circulation possible in this second coil.

What devices can you reload wirelessly ?

As we mentioned earlier, the electric toothbrush is the first device to have taken advantage of wireless charging. More and more smartphone models have this wireless charging technology. Indeed, your device must be equipped with an integrated “receiver” to be able to convert the electromagnetic field by current.

Wireless recharging has really been the wind since brands like Apple, Samsung, LG or Motorola equip their brand new smartphones in this technology. The most used wireless charging standard is the Qi standard (pronounce “tchi”), which allows you to recharge all devices on the Qi charging bases at airports and cafes.

If your device is not compatible, you can use a special charging cover equipped with integrated wireless charging technology. A USB port inside the cover establishes the connection with your phone. This rather tedious technique is not very popular. Indeed, wireless recharge has the major advantage of no longer having to physically connect the device to a charger and this special cover does not allow you to benefit from it.

For the moment, wireless recharge is mainly associated with smartphones, but we also find this technology at other devices. Tablets are of course part of it, since they are very similar to smartphones. New Wearables and Smart Watches can also be wirelessly loaded. There are also household appliances that are easily rechargeable wirelessly, such as electric and vacuum cleaners and vacuum cleaners. The situation also evolves enormously in the electrical mobility sector. We will come back to this at the end of this blog article.

Wireless recharge: advantages, but also disadvantages

The increase in the level of stress of the average user of a smartphone is proportional to the drop in the level of load of the battery. We have all already experienced this situation: the battery is emptied and you have to find a power outlet where you cursed yourself because you have not taken a charger. As could be practical, at that time, to put your device on a charging basis, to enjoy a coffee break and get back on a little later with a well recharged battery.

To load wirelessly, you obviously also need a power outlet. Indeed, the charging base is powered by the electrical network. Wireless recharge is also slower than direct recharging through a cable. Also note that the use of a wireless charger can heat your device more quickly, which can be prejudicial, in the long term, for the battery life.

So be vigilant when you use a charging base: their quality may vary and several wireless charging devices on the market are likely to damage your phone. Always check if the base is “Qi certified” and displays the Qi logo. The cheap bases sometimes have the mention “Works with qi” or “Qi compatible”, which is not the same thing. “Qi” is indeed the standard for an energy transfer of low power over a distance of up to 4 cm.

The future is wireless

We have a lot of work to do with this wireless charging technology. Take the example of electric cars: a vehicle equipped with this technology is currently experienced in Rotterdam. Suppose all taxi or parking lots have wireless charging stations. This would result in increased ease of use for electric cars users and this would motivate more people to consider buying this type of vehicle. A generation of electricity generation project by solar energy on a portion of highway was launched in China recently. It aims to test in detail how to load electric cars by means of induction.