View Full Version : Shake that Phone. Piezoelectric Energy Harvester.

06-04-2010, 06:42 AM

Piezoelectric kinetic energy harvester for mobile phones
31 March 2010
Countries: United States, WorldWide
Piezoelectric kinetic energy harvester for mobile phones

Earlier this year, Nokia filed a patent for a "Piezoelectric Kinetic Energy Harvester" for mobile phones. The aim is a self-charging mobile phone that will be powered by the energy created from a person's movements.

A "piezoelectric kinetic energy harvester" works by generating electricity from crystals which are bent or compressed by movement and Nokia's device could power a phone or any other portable electronic device, removing the need for batteries.

According to New Scientist "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".

The Patent summary states: "In a device according to at least some embodiments, kinetic energy resulting from acceleration of a battery powered device is harvested using piezoelectric elements that are positioned to receive forces along multiple different axes. So as to increase the amount of forces on those piezoelectric elements, the mass inducing such forces is increased by locating heavier device components within an assembly that transfers forces to the piezoelectric elements in response to device translation and/or rotation. In some embodiments, the device battery can be contained within that assembly. In still other embodiments, a display, a transceiver, a keypad and/or other device components are contained within that force-transferring assembly. In response to translation and/or rotation of the device, portions of forces induced by the battery mass and/or other device components are transferred to the piezoelectric elements. Electrical energy output by these piezoelectric elements is received in a power controller and can be applied to the battery".

A device such as this would be ideal for the millions of people in Africa who live without access to regular electricity to charge their mobile phones. And although Nokia would not reveal when such a device would appear on the market, it is exciting that the first steps have been taken in the form of a patent.

06-05-2010, 04:36 AM