Your Complete Guide to Wireless Charging
Today, wirelessly charging cell phones and other portable electronics is largely taken for granted, but many recall — and still experience — using cables and electric outlets.
Since its inception, wireless charging has significantly impacted and revolutionized the consumer electronics industry. Through the years each standard has offered unique advantages and limitations, catering to various user needs. Here’s a look at the progression of wireless charging technology, examining key milestones, distinctive features, and possible futures of Qi, MagSafe, and Qi2.
Secret origins.
Wireless charging is a technology that allows devices to deliver power over air without the need for a physical connection. Its secret origins date all the way back to the late 19th century when Nikola Tesla experimented with wireless power transmission in the form of electrical energy. In 1904, he built the Tesla tower that successfully transferred electricity wirelessly and lit bulbs from 30 feet away. Wireless power was born, but it took several decades for the technology to become practical, mass-produced, and accessible to the public.
Inductive charging vs. resonant charging.
Tesla’s pioneering experiments paved the way for both
resonant and inductive wireless charging methods.
Resonant wireless charging
relies on a high-frequency oscillating magnetic field transferring energy between two coils operating at a common resonant frequency.
The techniques were developed in parallel and have different benefits and drawbacks. Resonant charging covers greater distances and doesn’t require the tight alignment that inductive does. The drawback of resonant is that coils are bigger, making the system more expensive.
Inductive wireless charging
creates a relatively low-frequency oscillating field to transfer power between non-resonant but closely coupled coils.
One benefit of inductive charging is that it’s highly reliable when the device and the charging pad are in direct contact. Its widespread adoption is another of this method’s pros. Drawbacks include slower charging and the necessity for the device charging to be in close proximity to the charging pad.
Setting wireless charging standards.
The Wireless Power Consortium (WPC) is a group of tech industry leaders founded in 2008, and currently includes heavyweight partners such as Apple, Samsung, Nokia,Sony, and Belkin. Its aim was to create a universal standard for wireless charging that would be compatible with a wide array of devices, from smartphones to wearables. The WPC supported the Qi (pronounced chee) wireless charging standard.
Qi comes from the Chinese word 气 qi; traditional Chinese: 氣 meaning vital energy. Since its introduction, the Qi standard has undergone multiple iterations, improving efficiency, and reducing charging times. Achieving Qi certification recognizes that a device works properly and is safe to operate. During the technology’s evolution, Belkin has been a leader in designing accessories with the Qi charging standard.
Qi converts the
masses.
Qi was the first major breakthrough in
wireless charging using electromagnetic
induction to power devices.
The charging pad and your phone both house copper wire coils, and plugging the pad into a power source causes the charger’s coil to generate a magnetic field. When you place your phone onto the charging pad, the phone’s coil converts that magnetic field back into an electric current, thus charging the phone. In 2010, version 1.0 of the Qi wireless charging standard debuted, with single coil transmitter, coil array transmitter, and moving coil transmitter designs. The original charging pads were hulking, bulky, and slow, only delivering up to 5W of power charging to devices.
For tech enthusiasts
But the charging landscape changed dramatically with the advent of this tangle-free experience. In 2015, Belkin joined the WPC and the following year, we released our first Qi-certified charger. Since then, Qi has steadily improved, and today it’s the gold standard for wireless charging, setting the benchmark for compatibility and performance. Qi’s superpowers are its versatility and reliability, and it’s widely adopted in smartphones, earbuds, AirPods, and other devices.
MagSafe raises stakes and speed.
With the launch of the iPhone 12 model series in 2020, Apple introduced the world to MagSafe. MagSafe is a proprietary wireless charging system that magnetically attaches to the back of compatible iPhones. The technology offers faster charging speeds than Qi and also supports accessories like magnetic cases and chargers. Apple's sleek, magnetic take on wireless charging provides more precision and stability compared to Qi, but it’s only compatible with Apple devices. MagSafe-certification ensures the charging pad or stand has the required magnetic technology and is safe to use with compatible iPhone devices. Dovetailing with the debut of MagSafe, Belkin introduced its first MagSafe-compatible charging accessories in 2020.
For tech enthusiasts
MagSafe’s bells and whistles add magnets to the mix for a physically tighter connection. Its magnetized connector on the back of the iPhone allows the phone to snap into place precisely on a MagSafe charger, making it convenient to align and charge compared to traditional Qi charging. In addition to magnetics, another MagSafe superpower is its faster charging speeds versus most Qi charging pads, and some models are able to deliver up to 15 watts of power.
Magnetic Qi hits the scene.
Magnetic Qi is identical to Qi in terms of charging speed and the only difference is that it includes a non-certified magnetic module similar to MagSafe to enable compatibility with MagSafe-compatible iPhones. Some magnetic Qi products have strong holds and others have weak magnetic holds, depending on the quality of the build by the manufacturer.
For tech enthusiasts
The WPC plans to mandate magnetic elements including strength and magnet strength will be one of the elements tested as part of the certification process. Because there’s currently no standard of magnetic hold with magnetic Qi products, you should only buy from trusted brands.
Qi2 takes an evolutionary leap.
The WPC ushered in the next generation of Qi wireless charging technology in 2023 with the introduction of the WPC 2.0 standard. Qi2 integrates Apple's MagSafe technology, providing better alignment between the charger and the device and allowing users to charge up to 2X faster with Belkin Qi2.* It adopts a safety- and certification-first approach by leveraging smart microchip technology to ensure charging is safe and efficient. In essence, the technology performs a "handshake" between the device and the charger to verify that both possess Qi certification before it starts charging. At launch, Belkin was the only WPC member to certify two Qi2 charging products.
For tech enthusiasts
One of Qi2’s superpowers is supporting higher Power Delivery "far-field" charging, supplying up to 100 watts of power. This permits simultaneous charging of multiple devices and powering more energy-intensive electronics like laptops and tablets. However, the 100 watts of power is not yet available for wireless charging of smartphones. Another key improvement is the introduction of "mid-field" charging, which allows for charging at up to 15 watts without direct contact between charger and device. This application is great for devices like earbuds and smartwatches that tend to have small charging pads.
Other enhancements are faster charging speeds, improved efficiency, and advancements toward universal compatibility. True universal compatibility will be realized once other devices adopt the Qi2 standard and this list compiles current compatible devices. Universal compatibility will eliminate the need for separate chargers and ensure users can charge multiple devices with the same charging pad or stand without worrying about standards and protocols. By optimizing power transfer, Qi2 improves efficiency, enabling devices to quickly charge without compromising energy consumption. The technology’s futuristic design eclipses predecessors in the speed, convenience, and efficiency departments.
Future trends in wireless charging technology.
As wireless charging technology continues to evolve, it’s projected to increasingly integrate into our lives in ever more seamless ways. Developers are working on advancements in longer-range charging and more eco-friendly solutions. Potential developments include wirelessly charging electric vehicles and designing in-display or in-table charging. With this technology, power can be transmitted through the screen or surface of a table.
This eliminates requiring physical charging ports altogether and would make devices even more seamless and convenient. Moving forward, the WPC is also focusing on improving the safety and security of wireless charging technology. Proper certifications that correlate with charging standards are a key component. As devices become more powerful and charge faster, it's critical to employ safety measures to prevent overheating, electromagnetic interference, and other potential hazards.
Shop our latest Qi2 wireless chargers.
*Based on internal testing. Belkin Qi2 15W wireless charger charges iPhone 15 from 0-50% up to 2x faster than a Qi 5W wireless charger and up to 1.5x faster than a Qi 7.5W wireless charger. Charge time varies with environmental factors; results may vary.
