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Recharging Gadgets Wirelessly

A metal pad that can recharge devices placed on top of it has come to market.
December 13, 2007

The chore of recharging cell phones, PDAs, MP3 players, cameras, and laptops is perhaps one of the more frustrating side effects of modern technology. Charger cables are usually tangled in nests near outlets or behind desks. And anyone traveling for more than a day with an electronic gadget has to tote along its clunky charger as well. A Delaware-based startup called WildCharge thinks that it has a better approach. The company is selling a small metal pad, about the size of a sheet of paper, that can simultaneously charge multiple devices laid on top of it–as long as they’re equipped with adaptors. WildCharge is now selling an adaptor for Motorola Razr phones, and it’s developing others.

Power pad: Delaware-based WildCharge has developed an electrically conducting pad that charges phones and other devices via adaptors. Above, the battery cover of a Motorola Razr mobile phone has been replaced by WildCharge’s adaptor, which has four metal contacts arranged in a Y shape.

“WildCharge is the industry first in wire-free charging,” says Mitch Randall, the company’s chief technology officer and inventor of the technology. He says that it was easy to bring the power pad to consumers because the technology is fairly straightforward, while other companies and research teams are still ironing out kinks in their approaches. “There are no other competitors on the market because they’re still fighting their technology,” he says. “Ours just works, and it’s cheap.”

In recent years, a number of wireless-power technologies have garnered some attention. Researchers at the University of Tokyo have developed a sheet of plastic with printed electronics that charges gadgets using a technique known as inductive coupling. (See “Plastic Sheet of Power.”) In the researchers’ prototype, electric current flows through a coil, inducing a magnetic field. This magnetic field, in turn, induces a current in a coil within or attached to a device that is touching or nearly touching the pad–the same way that an electric toothbrush charges on its pedestal. Still, the research is early, and the printed electronics aren’t reliable enough to be used in a commercial product. At MIT, another group of researchers recently demonstrated a wireless-power setup that uses large coils to charge gadgets up to three meters away; they are currently working to commercialize the technology. (See “A Wirelessly Powered Lightbulb.”)

Randall explains that WildCharge took a different, simpler approach. The power pad–originally designed to power action figures for a child’s game–consists of metal strips that conduct electricity. In order for a gadget to be recharged by the pad, it needs an adaptor, which plugs into its charging port and consists of four metal contacts. When the contacts touch the metal strips on the pad, electricity flows directly into the battery of the gadget. Essentially, the contacts “close the circuit,” says Randall, “just like flipping a light switch.” For safety, Randall says, the pad shuts down when an object that isn’t WildCharge-enabled comes in contact with it; but the mechanism behind that feature is proprietary, he says. If there are no devices in contact with the pad, then after 30 seconds, it goes into a standby mode to conserve power.

Currently, WildCharge offers adaptors only for Motorola Razr phones, but Randall says that his company will soon unveil others that work with iPods and smart phones, including the iPhone. The Razr adaptor replaces the battery cover that comes with the phone, but Randall says that future adapters will look like the rubber sleeves that many people use to protect their handhelds from scratches and other damage. “If you go to an Apple store, you’ll see a whole section of protective gel or hard rubber material that usually covers the back of a device and leaves the front open,” says Randall. “We have a thing just like that. Embedded into that gel are our electronics.”

While the company isn’t releasing the names of any partners, Randall says that it has been in talks with cell-phone manufacturers interested in learning more about integrating the technology into their phones. At the outset, says Randall, manufacturers generally have concerns about heating, electromagnetic interference, and other effects of inductive coupling. “They are the experts at testing inductive wire-free technologies because they’ve seen a few of them go through their labs,” says Randall. But since the WildCharge pad doesn’t use inductive coupling, he says, it doesn’t have the associated problems.

The company has already received significant recognition for its product. It was honored as a 2008 International CES Best of Innovations Design and Engineering winner, an award presented by the Consumer Electronics Association, which puts on the annual Consumer Electronics Show in Las Vegas. Also, Time magazine picked the WildCharge pad as one of the top innovations of 2007.

The pad definitely appeals to people’s desire to disconnect from wires, says Roger Kay, the president of Endpoint Technologies Associates, a technology analysis firm. “Ultimately, what it saves is having to plug the device in and some of the messiness of power cords,” he says. “That’s probably the biggest impact.” But, Kay adds, in order for the pad to win widespread adoption, WildCharge will need to keep down the cost of its adaptors, whether they’re snapped on by customers or embedded by cell-phone manufacturers. “It’s got to be very cheap, so that it’s a no-brainer from the user’s point of view,” Kay says.

Randall believes that the technology’s cost is low enough to make it appealing, but he also expects that people will truly value using the WildCharge pad. He says that some early customers have already derived unexpected benefits from using it, beyond simply avoiding messy cords. For one, he says, since people tend to set their phones on the pad when they’re in their houses, they don’t lose track of them as often. Also, since using the pad becomes a habit, phones tend to be more fully charged when they’re needed, giving the impression of lengthened battery life. And once the new adaptors arrive, travelers will need to pack up only the power pad, instead of lugging around a mass of plug-in cords, Randall says.

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