The WildCharger can recharge a variety of handheld devices at the same time by placing them on a metallic pad. Sources familiar with the technology say it works by placing a device, fitted internally or externally with an adapter, onto the pad. When contact is made, power is sent between the two.

Rival technology eCoupled transfers energy through the air over short distances to devices one at a time, using what's called adaptive inductive coupling. A wireless adapter senses how much power a specific device's battery needs and adjusts the energy transmitted accordingly.

The first consumer version of an eCoupled product is a car cup holder that recharges devices set inside it. It only needs to be plugged into the car's 12-volt outlet -- or cigar lighter as it's more commonly known.

Devices using the charger will initially need an add-on, similar to a Bluetooth adapter used for mobile phones. But the next step is a battery pack for phones that does away with the adapter. Eventually it is hoped that manufacturers will integrate the technology from scratch.

If the technology succeeds, it is envisaged that homes, offices, and public spaces will be outfitted with pads or hot spots that would supply power for a host of mobile devices.

"The strategy is if I buy a battery, I can charge my laptop just by setting it down on my desk," said eCoupled lead inventor Dave Baarman.

"People are sick of buying a new adapter every time they buy a new electronics device. How many adapters do you throw away when you get a new phone?" said Baarman. "The social aspect of being able to have one adapter that powers all those devices is much more environmentally friendly and universally friendly to the consumer."