Mobile phone supplier Nokia is developing a self-charging phone that will use the kinetic energy created when a person moves around to ensure that the mobile never runs out of juice, the Times of London reported Thursday.
The plan was revealed in a patent application seen by The Times and filed with U.S. authorities. The new device could power a phone, but the concept could transfer to any portable electronic device -- such as a music player, medical equipment or games console -- and so could do away with the need for batteries and chargers altogether.
The machine would work through the use of piezoelectric crystals, a substance that creates an electric current when bent or compressed, for example in the igniter of a cigarette lighter or in a gas oven.
In the past, making highly-efficient crystals that could be used within a gadget such as a phone was impossible, as they would have to be created at high temperatures that would destroy most materials, like plastic or rubber. But recent developments, including work by scientists at Princeton University that would allow piezoelectric crystals to be “printed” onto a flexible, rubber-like material, means they may soon be used in portable devices.
In Nokia's proposed design, the heavier components of a phone, such as the radio aerial and battery, are supported on a strong frame. This frame can move alongside two sets of rails.
Strips of piezoelectric crystals would sit at the end of each rail. They would create an electric current when hit and compressed by the frame. So when a person gets up, walks across a room or in any way moves the phone, the movements would create electricity. The energy created would charge up a capacitor that would in turn charge up a battery, keeping it topped up constantly.
Nokia would not reveal when such a device would appear on the market.