Power cables and even batteries might become a thing of the past using a new technique that can transmit power wirelessly to cell phones, laptops, MP3 players, household robots and other electronics. Scientists lit a 60-watt light bulb from a power source 7 feet (2 meters) away with their new technique, with no physical connection between the source and the appliance. The researchers have dubbed their concept ‘WiTricity,’ as in ‘wireless electricity.’ MIT physicist Marin Soljacic began thinking years ago about how to transmit power wirelessly so his cell phone could recharge without ever being plugged in. Scientists have pursued wireless power transmission for years - notably, eccentric genius Nikola Tesla, who devoted much energy toward it roughly a century ago. The problem with wireless power transmission is that broadcasting energy in all directions - say, as radio waves - can be tremendously wasteful, with a vast majority of power ending up squandered into free space. One could imagine focusing energy along just one or a few directions - say, using laser beams - but such approaches can readily prove dangerous and cumbersome, requiring an uninterrupted line of sight between the source and device as well as […]