With a mature mobile strategy, the state of Delaware appears to be an ideal candidate to deploy wireless charging technology. Buying different sets of wall and car chargers can be expensive and cumbersome, and wireless charging could help solve that problem, says Bill Hickox, chief operating officer for the Delaware Department of Technology and Information.
However, the perceived immaturity of the technology is holding the First State back at this point. “We haven’t focused a lot on wireless charging technology because it’s still in its infancy,” Hickox says. “We would love for it to become more mature.”
The technology is poised to advance this year if manufacturers of smartphones, wireless chargers and cars adopt standards for next-generation wireless charging products based on magnetic resonance.
Several smartphones, such as the Google Nexus, LG Optimus and Nokia Lumia, incorporate the Qi inductive power standard, which uses magnetic induction technology to transfer power from a charging pad to a smartphone’s battery. However, the phone has to have direct contact with the charging pad.
Resonant technology offers simultaneous charging of multiple devices with different power requirements, as well as spatial freedom. The technology lets people charge multiple mobile devices on a single charging surface without having to hassle with accurate positioning or alignment.
When the Wireless Power Consortium (WPC) launched the Qi standard in 2008, inductive technology offered the most efficient way to transfer power between the charging pad and the mobile device. The first version didn’t work well because the user had to place the phone precisely on the charging pad, says John Perzow, vice president of market development for WPC.
The second generation of the Qi specification brought more improvements, and the third iteration incorporates resonance technology. “We have already demonstrated that it’s working at the Mobile World Congress,” Perzow says. The key is the technology must be backward compatible with the 40 million Qi-enabled mobile devices on the market, he says.
Meanwhile, an agreement between the Alliance for Wireless Power (A4WP) and Power Matters Alliance (PMA) could further expand the reach of resonant technology. PMA is adopting the A4WP Rezence specification.
“Magnetic resonance–based wireless power transfer has been used in transportation and industrial applications for decades,” says Kamil Grajski, president and board chairman of A4WP. Advancements in micro-electronics have made it possible for the technology to be implemented in consumer electronics.
Backed by manufacturers such as Broadcom, Intel, Qualcomm and Samsung, the A4WP developed a specification for interoperability and performance and a certification process for products. The member companies now have everything they need to bring products into the marketplace this year, Grajski says.
In turn, the A4WP will adopt PMA’s open network API to turn individual charging stations into wireless power networks capable of supporting any wireless charging technology.
Regardless of the technology — inductive, resonance or, in the future, electrostatic — the bigger picture is how to get rid of charger adapters and still have efficient, quick charging, says Ron Resnick, president of the PMA, whose technology is deployed in select Starbucks and McDonald stores. “We need to come up with a model that harmonizes all of the technology coming out and that will be acceptable to government employees as well as consumers and business users,” he says.
How Resonance Charging Works
Resonance wireless charging is designed for devices that need a lot of power, such as smartphones, notebooks and even electric cars. The technology uses two copper coils tuned to the same electromagnetic frequency: one in the power source, the other in the mobile device. When devices of the same resonant frequency are placed together, the energy produced can be transferred from one to the other.
Kamil Grajski, president of the Alliance for Wireless Power consortium, describes a letter-sized piece of paper with a few loops of wire around the perimeter that becomes a charging surface. The phone needs to be within a prescribed surface, but there’s a lot of room for horizontal, vertical and angular flexibility, he says.