Browse Prior Art Database

PowerLink System for Portable Products

IP.com Disclosure Number: IPCOM000004832D
Original Publication Date: 2001-Jun-27
Included in the Prior Art Database: 2001-Jun-27
Document File: 3 page(s) / 31K

Publishing Venue

Motorola

Related People

Daniel Gamota: AUTHOR [+2]

Abstract

PowerLink System for Portable Products

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This is the abbreviated version, containing approximately 78% of the total text.

PowerLink System for Portable Products

Daniel Gamota, and Nadia Yala

BACKGROUND

Portable electronic products are typically powered by batteries, which may or may not be rechargeable. The power consumption of electronic products and battery capacity generally determine the longevity or charge retention interval of the battery. The charge retention interval represents a time period from a fully charged battery to a substantially discharged battery with a depleted charge. In the case of cellular phones, battery longevity or charge retention interval may be rated by talk-time, stand-by time, or some combination of the foregoing.

As battery size and weight are decreased, the battery longevity and charge retention interval is generally compromised. While consumers may prefer the lightest and smallest portable electronic products, shortened battery longevity and shortened charge retention intervals are significant obstacles in reducing the size and weight of some portable electronic devices. Diminished battery capacity leads to more frequent recharging from battery chargers powered by alternating current lines. Consumers may be inconvenienced by downtime accompanying increased recharging frequency. Moreover, taking portable electronic devices out of service for battery charging tends to reduce wireless traffic and revenue for wireless telecommunication providers. Reduced battery capacity may lead to additional unwanted purchases of batteries along with the attendant disposal costs and environmental concerns associated with spent batteries.

PROBLEM

A need exists for increasing charge retention intervals, reducing recharge frequencies, and enhancing battery longevity, while minimizing size and weight of portable electronic devices.

SOLUTION

The present invention relates to a kinetic-to-electrical energy converter adapted to impart electrical energy to electric energy storage devices, such as batteries.

A kinetic-to-electrical energy converter comprises a piezoelectric structure, an actuator in mechanical communication with the piezoelectric structure, a rectifier adapted to receive electrical energy from the piezoelectric structure, and an electrical energy storage device coupled to the rectifier (Figures 1A and 1B). The piezoelectric structure has a relaxed state and a stressed state. The piezoelectric structure has output electrodes and is capable of generating electrical energy at the output electrodes in response to a transition between the relaxed state and the stressed state. The actuator for applying external force has a rest position and an activated position. The actuator is preferably movable in response to the application of an external force to deform (i.e. compress) the piezoelectric structure in the activated position. The rectifier is coupled to the output electrodes to receive electrical energy. The electrical energy storage device is coupled to the rectifier for receiving and storing electrical energy.

In practice, the electrical energy storage dev...