The struggle of finding a charging outlet is a struggle of the modern world. Mobile phones, laptops, and wearable devices have changed the way we work, live, and play—but the convenience is still tethered to the nearest electrical socket. The increasing computational capability of our devices, the lag in rechargeable battery capacity to keep up, and the increasing dependency on technology in our everyday lives certainly makes quick and efficient power charging highly desired.
Furthermore, the frustration of every other device requiring its own proprietary charging interface makes the experience of powering our electronics frustrating at times. Having to carry multiple charging cables can be cumbersome because they're easily lost and sometimes difficult (or expensive) to replace.
Currently, there is no universal charging standard, although the European Union did pass a bill in 2014 requiring all phones to use a common charger by 2017. (This was not put forth as a way to increase convenience but rather as an effort to reduce electronic waste.)
With wireless charging, ubiquitous and common charging interfaces will be the way of the future—a very attractive prospect enabling more mobility, less dependance, and increased convenience.
Wireless charging is the natural next step in the mobile electronics world, but although the technology is available, it has yet to really catch on. IHS Markit, a technology analytics organization, reported that 25% of consumers have actually used wireless charging and that 80% of consumers have heard of it. In 2014, only 36% had been reported of knowing about wireless charging and, in 2015, 76%.
One of the major hurdles is the current standard battle occurring among several competitors. This isn’t the first standard battle to occur in technology history. Betamax vs VHS, cassette vs 8-track, HD vs Bluray—every generation has one. It may very well be that until one standard becomes king, ubiquitous wireless charging will remain on standby.
However, each standard has its own pros and cons. Regardless of the standard’s technical specifications, efficiency, or range, what will make a standard successful is its successful wide-scale implementation, along with ease of use. The first standard to become widely available the quickest will likely emerge victorious, and so mass efforts in partnerships and implementation are certainly underway by all the companies and organizations involved.
Image courtesy of xkcd.
Here is a brief overview of some of the current available standards, in alphabetical order.
Charging method: Resonant, inductive, and uncoupled (RF, ultrasound, laser)
Charging delivery: Contactless, contact
Max. charging distance: 15 feet (uncoupled)
Multiple devices: Yes
Contact required: No (resonant), yes (inductive), no (uncoupled)
AirFuel Alliance was created from the merging of the Power Matters Alliance (PMA) and the Alliance For Wireless Power (A4WP). While the PMA specification is quite similar to Qi’s using inductive charging, which requires contact and has a short range (but is more efficient), A4WP utilized a different charging method via resonant charging. This allowed for longer distance between charging transmitters and receivers.
However, typically the trade off in long-distance charging is that charging will occur much more slowly. However, AirFuel Alliance also has RF charging implementations underway, bridging the gap between charging range and efficiency. With the merging of PMA and A4WP, AirFuel Alliance now has the advantage of both standards.
PMA has already been implemented in Starbucks across the USA as of 2015, and AirFuel Alliance is undergoing wide-scale implementation of wireless charging stations across in Shenzhen, China. Resonant charging will allow multiple devices to be charged at once, while in motion, without the need for charging pads.
AirFuel Alliance is currently used by Dell, Samsung, LG, Motorola, and Kyocera.
Inductive charging diagram. Image courtesy of AirFuel Alliance.
Charging method: RF
Charging delivery: NEST cradle
Multiple Devices: Yes
Max. Charging Distance: Within NEST cradle
Orientation Specific: No
Contact Required: No
Humavox is an Israeli-based company that was founded in 2010. It has established itself in the wearables and small medical device wireless charging market using RF charging, providing large charging ranges while remaining highly efficient. The company calls its wireless charging standard ETERNA, a standard which allows flexibility for manufacturers in how it is implemented in their products.
ETERNA is comprised of a charging NEST in which a device, which would have a built-in charging receiver, is placed and charged. The NEST can be integrated into any enclosed environment, such as purses or desk drawers.
Humavox is trying to make it easy for manufacturers to implement their technology via out-of-the-box components. ThunderLink is a 2mm wireless charging receiver which can be used with a variety of consumer electronics, which can be easily integrated into devices.
Humavox's wireless charging ecosystem. Image courtesy of Humavox.
Charging method: Inductive-resonant coupling
Charging delivery: Charging pad
Max. charging distance: 40 mm
Multiple devices: Depending on implementation
Contact required: Yes
Orientation specific: Depending on implementation
Pronounced “chee”, Qi was founded in 2008 and has had a bit of a head start in the wireless charging world. The standard is already used by a variety of mobile phone manufacturers, including Samsung, HTC, ASUS, Huawei, Blackberry, Sony, and LG with a variety of aftermarket charging pads available for consumers.
Qi can be used in both orientation and orientation-less configurations. In orientation-based platforms, a single inductive transceiver is used. In orientation-less configurations, a variety of methods is implemented by using inductive transceiver bundles, transceivers which can orient themselves into place or through an array of variable configuration transceivers.
Qi plans to roll out wireless charging stations, called "Qi hotspots", in coffee shops, restaurants, airports, and libraries, so that wireless charging is available the same way Wi-Fi is. The first airports to implement Qi hotspots are expected to be London Heathrow Airport and New York City’s John F. Kennedy International Airport.
Qi also is developing aftermarket wireless charging products for automotives, preparing for the shift to electric vehicles in the future.
Qi wireless charging diagram. Image courtesy of Qi.
Featured image courtesy of Samsung.