Wireless charging is in high demand these days, with a surplus of devices flooding the market. But none of these so-called "wireless chargers" function without wires or from a distance. So, what's preventing the world from creating true wireless charging?
When you think of wireless charging, you're probably thinking of one of the many Qi chargers offered by various top wireless tech and mobile companies. But let's be honest, a charger that has to be plugged into an outlet and requires the device to be aligned to its surface is by no means wireless.
While several major companies announced new or improved wireless charging methods, none have been released yet. Some projects, like Xiaomi's Mi Air Charge, are still building hype. Others, like Apple's long awaited AirPower charger, have already been abandoned. The question is what's preventing the tech industry from creating a true wireless charger that works?
Limits to current wireless charging technology
To understand the issue, we must understand the limitations of the technologies currently in use. They are inductive, resonant, and radio frequency (RF).
Inductive and resonant charging both use copper coils to induct or resonate the heat (ie. energy) from a transmitting device's coil to a receiving device's coil, before it is converted to power. Since the heat of the coils will dissipate or disperse if there is too much air between transmitter and receiver, they must be touching or in very close proximity to transfer the amount of energy necessary to be considered an efficient charging device. The coils are also limited in power due to heat-safety mechanisms to ensure that the charger or your device won't catch fire or cause a burn.
RF transmitters send out energy from its antenna amplifier that is then picked up by a receiver device's antenna which converts it into power. This method allows for devices to be charged from several meters away, but the devices are limited in size and the power they can emit, restricting its use to low-energy devices. Furthermore, as the physical gap widens between transmitter and receiver, so does the amount of energy loss. As a result, RF is energy inefficient and impractical for long-range.
The future of wireless charging technology
In the last year, several companies announced new or improved wireless technologies capable of powering devices from a distance. They include RF, electromagnetic resonance, and infrared (IR).
RF has been around for some time but was mostly limited in scope. Recently, Ossia's Cota has received regulatory approval in 60 countries and shows much promise in powering the ever-growing world of IoT. While not energy efficient, it does provide power for medical and industrial devices that only need low amounts of energy at distances of several meters.
Magnetic resonance has made a name for itself thanks to Wi-Tricity, a company rooted in MIT's physics department. Their technology is already powering wireless devices such as phones and wearables, though with the limitations listed above. There have been recent breakthroughs which include higher frequency charges and from greater distances, but this focus or capability has only taken shape with EV wireless chargers, and it is still limited to a few meters.
IR has been making some big splashes in the world of wireless charging, most recently at the CES 2022 event. Wi-Charge, the company behind infrared power innovation, has already partnered with multiple commercial companies to incorporate its technology in an array of consumer products. They also recently launched a turnkey digital wireless display, Wi-Spot, that has become a huge hit in retail and grocery stores worldwide.
If Wi-Charge has its way, smartphones and all consumer products will be powered with IR, finally freeing devices from batteries and cords for good.