Wireless Power Consortium Announces New Qi2 Standard With MagSafe-like Capabilities

Wireless Power Consortium (WPC), -- the organization that oversees the Qi wireless charging standards -- this week, announced a new version called Qi2, which it worked on with smartphone giant Apple to bring MagSafe-like capabilities to Android.

Apple introduced the wireless standard, MagSafe for its iPhones, over two years ago. This collaboration with the WPC will open up Qi2 to a ton of magnetically attachable accessories including chargers, and gets rid of the difficulty of having to align the phone with the wireless charging pad, with magnets that snap to the back of the phone perfectly.

The WPC said that Qi2 introduces a Magnetic Power Profile -- built on the basis of Apple’s MagSafe technology. “Qi2’s Magnetic Power Profile will ensure that phones or other rechargeable battery-powered mobile products are perfectly aligned with charging devices, thus providing improved energy efficiency and faster charging,” the consortium said in a press release.

Full specifications for Qi2, have not been released, but WPC spokesperson reportedly said initial charging speeds will cap at 15W, as they begin work on higher power profiles for the standard at a later stage. The consortium said Qi2, which will replace the existing Qi standard, will be released later this year.

The WPC said Qi2-compatible accessories should be available before the end of the year. This new standard will pave way for accessories “that wouldn’t be chargeable using current flat surface-to-flat surface devices.” This could be used for charging different kinds of headphones or smartwatches. Overall, the new standard might set the stage for a faster magnet-enabled wireless charging experience.

There are 3 main types of wireless charging pads: ones that use tightly-coupled electromagnetic inductive or non-radiative charging; charging bowls or through-surface type chargers that use loosely-coupled or radiative electromagnetic resonant charging that can transmit a charge under an inch; and uncoupled radio frequency (RF) wireless charging that allows a trickle charging capability at distances of many feet.

Both tightly coupled inductive and loosely-coupled resonant charging operate on the same principle of physics: a time-varying magnetic field induces a current in a closed loop of wire.

A magnetic loop antenna (copper coil) is used to create an oscillating magnetic field, which can create a current in one or more receiver antennas. If the appropriate capacitance is added so that the loops resonate at the same frequency, the amount of induced current in the receivers increases. This is resonant inductive charging or magnetic resonance; it enables power transmission at greater distances between transmitter and receiver and increases efficiency. Coil size also affects the distance of power transfer. The bigger the coil, or the more coils there are, the greater the distance a charge can travel.

Smartphone charging pads are based on resonant inductive charging, though the copper coils in this case are less than a few inches in diameter, severely limiting the distance over which power can travel efficiently.

Charging pads have been shipping in volume since 2015. Over 200 million wireless charging-enabled devices shipped in 2016, with almost all of them using some form of inductive (charging pad) type design.

For several years, there were three competing wireless charging standards groups focused on inductive and resonance charging specifications: The Alliance for Wireless Power (A4WP), the Power Matters Alliance (PMA) and the Wireless Power Consortium (WPC). The latter's 296-member roster includes Apple, Google, Verizon and a veritable who's who of electronics manufacturers.

In 2015, the A4WP and the PMA decided to band together to form the AirFuel Alliance, which now has 110 members, including include Dell, Duracell, Samsung and Qualcomm.