Gone are the days of plugging in your electronics and being tethered down in order to charge. As our tech is evolving, so is the way we power up – and the latest evolution is in wireless charging.
Qi, a Chinese word that translates to “vital energy,” is today’s worldwide wireless charging standard that can provide 5 to 15 watts of power. These days you’ll find it within a variety of smaller electronics—such as smartphones—but Qi tech is spreading to other devices too. With most devices adopting Qi standards, wireless charging is rapidly becoming a selling point of new technology, changing the way we charge at home, in the office, and even on the go. Here, we’ll give you an overview of how it works, where it’s used, and a few safety-related considerations.
HOW DOES THIS SORCERY WORK?
Wireless charging can come in a variety of forms across many devices.
Radio Charging
Radio charging is a method of wireless charging, commonly seen in devices such as wireless keyboards and mice, certain medical devices, watches, and music players. These devices are powered by small batteries that use radio waves to send and receive wireless signals. When the device is configured to the same frequency as the power supply, the battery is able to charge.
Magnetic Resonance Charging
For larger devices that use a significant amount of power – such as a large computer, vacuum cleaner, or electric car – a method called resonance charging is used. Resonance charging requires a copper coil to be attached to the device receiving the charge and another copper coil attached to the source of power. A connection is formed when both copper coils are configured to a common electromagnetic frequency, allowing a transfer of energy from the power source over a relatively short distance, which charges the device on the receiving end.
Inductive Charging
Qi is a form of inductive wireless charging. It occurs when energy is transferred from a charger to a receiver by way of electromagnetic induction. The charger uses an induction coil to create an electromagnetic field, which the receiver coil in the device simply converts back into electricity to feed the battery. Typically, the two coils need to be nearly touching, with the receiver on top of the charger (or vice versa). Though this is considered by many to be cutting-edge technology, rechargeable toothbrushes and shavers have been using this kind of inductive charging since the 1990s. Wireless before it was cool.
WHO'S ON BOARD?
The mobile phone market remains the dominant force in overall use. The Samsung Galaxy, starting with the S7 model, come equipped with dual-mode Qi, meaning the device is compatible with the Wireless Power Consortium (WPC) standards as well as the Power Matters Alliance (PMA) standards, so they are able to charge with any wireless receiver. Although Apple didn’t release wireless charging compatible devices until 2017, iPhones now come Qi equipped (starting from iPhone 8 and versions beyond) which are compatible with any Qi certified charging device.
Wearables are also a big category it comes to wireless charging, driven by Apple, Samsung, and other popular brands. Even larger electronics have begun adopting wireless charging options. In 2017, Dell launched the world’s first wireless charging laptop with their release of the 2 in 1 Latitude 7285. But consumers are now seeking even more flexibility with their wireless charging. Energous, a wireless charging corporation, has created a wireless charging ecosystem solution that allows charging without contact up to 15 feet away, proving that the future of wireless charging is limitless.
Given access to all these Qi-supported products, it’s interesting that in a 2022 IHS poll, only 20% of respondents reported using wireless charging technology—and only 16% charged their devices with this technology on a daily basis. According to the Wireless Power Consortium, now roughly 40% of consumers regularly use wireless charging. So, while more and more people are converting to wire-free, most users consider wireless to be a good way to supplement wired charging, rather than a primary charging method. This could be due to the inefficiency of Qi charging compared to wired. Wired charging holds around 85% efficiency in the amount of energy sent out while QI charging has only risen to 75% efficiency from its initial launch percentage of 60%. Generally, wireless charging isn’t as fast as wired. In addition to that, the price difference between wired and wireless explains why adoption rates for wireless charging aren’t higher. Any wireless charger that would outperform a wired charger ranges $40-60, about double the price of any wired charger—and, well—people like a bang for their buck.
SAFETY ISSUES TO CONSIDER
The Qi Wireless Charging Standard, developed by the multinational Wireless Power Consortium, outlines several consumer safety precautions, including issues like heat shielding and foreign object detection, especially among non-certified equipment. Recent tests conducted by independent labs found that non-compliant charging products can reach almost 200° Fahrenheit—enough to cause a third-degree burn.
While many smartphones claim they are water-resistant, or even waterproof, most wireless chargers are not. As with all electrical devices that connect to a power outlet, liquid can be very dangerous. Users should never get a wireless charger wet and need to be sure any phone is dry before setting it down to charge.
A poorly made charger may also not be able to detect if a foreign object—like your keys or a coin is sitting on the pad under your smartphone. As a result, the charging pad may continue to emit power, not only damaging your device, but potentially melting the other objects on the pad. So, it’s important to look for a charger with a foreign object detector, one which will shut down charging and alert you (usually with an LED light) that something other than a compatible device is in contact with your charger.
Finally, when it comes to health and safety, a common cause for concern is the effect of electromagnetic fields (EMF) emitted by wireless chargers. High levels of EMF have been found to pose some health risks, however, the EMF emission levels involved in wireless charging are negligibly low as there is no sustained human contact with the charging pad. In fact, a study conducted by the World Health Organization (WHO) confirms that exposure to low EMF emissions does not lead to any known health problems.
THE QI TO SUCCESS
Ultimately, the broad success of Qi-Certified devices in the marketplace depends on all the elements interfacing seamlessly—regardless of manufacturer, country of origin, version used, etc. The Qi Wireless Charging Standard, mentioned earlier, is intended to do just that: to ensure a consistent and user-friendly experience, one where a phone placed on a wireless charger will work reliably, each and every time.
To find to out if your device is compatible, check out the Wireless Power Consortium’s product database tool. Already know that your device is compatible? Check out all the wireless charging options Byrne can provide at youmakebyrne.com, or shop wireless charging even faster at shop.byrne.com.
