New Delhi: What more could you ask for when charging your phone or watch if you could simply place these smart devices on a charging pad to resurrect their batteries?

The fact is that while users today do have many options to charge their mobile devices such as micro USB and USB Type C, they also have wireless charging pads that do not have cables dangling all over. Besides, the emergence of Qi charging technology as the universal standard in wireless charging has improved the odds for wider adoption. The Qi charger works by sending an electric current from the transmitting coil on the charger to the receiver coil on the glass back panel of the smartphone. It is one of the reasons why all smartphones with wireless charging have a glass back. Yet, wireless chargers are not ubiquitous, and the technology has not seen much traction for three main reasons.

First, barring Apple’s iPhone 8, iPhone 8 Plus and iPhone X; Samsung’s Galaxy Note 8, Galaxy S9 and S9+, and LG’s G7 ThinQ and V30, not many phones support wireless charging because adding wireless charging means additional cost for handset makers, which is why the technology is not available on any of the budget or mid-range smartphones.

Second, wireless chargers are flexible but they take a lot more time to charge as compared to USB-based chargers. A standard wireless charger can muster 5W of power, while the newer options allow power transfer of up to 7.5W. In comparison, USB-based chargers support power transfer of up to 20W and can charge a phone faster than any of the existing wireless chargers.

Third, a user needs to keep the device on the charging pad during the entire charging period. If a user gets a call and decides to remove the phone from the pad, the charging will stop. To be sure, California-based company Energous has developed a wireless transmitter which can charge a device wirelessly from a distance of over three feet by converting electric currents into radio frequencies. It can charge multiple devices at the same time by creating a bigger electromagnetic field of up to three feet. While the new transmitter can make life easier for users, experts feel it is going to be a lot slower.

“Through-air power transfer would be dream come true. Unfortunately, in reality, it’s not possible to do this practically or safely today due to a few basic physical properties that cannot be overcome. The low-level, through-air signal may charge a small device, such as a micro wearable, but anything that has a greater power requirement would make this unreliable and not practical - who wants to wait over 100 hours to charge an iPhone X?" said Cliff Weinstein, CEO of FLI Charge, a US-based charger company.

That said, there is a lot working in favour of wireless charging. There is a universal standard in Qi technology and devices which support it are no longer bulky. Having a wireless charger built in to bed stand or table can is very convenient for users, but unless users can get speeds at par with USB standards the adoption is likely to be limited. “Wireless charging is not going to replace USB-based charging anytime soon. Both will exist side by side for some time, but eventually wireless charging will replace USB connectors, once the ecosystem for wireless charging develops. Also without connectors to worry about, OEMs (original equipment manufacturers) can design more water-proof phones," concludes Pavan PudiPeddi, one of the founding member of Wireless Power Consortium(WPC), which developed the Qi standard

Close