Low power thermoelectric generator

Abstract

Disclosed is a foil segment for a thermoelectric generator comprising a top plate disposed in spaced relation above a bottom plate. An array of the foil segments is perpendicularly disposed in side-by-side arrangement between and in thermal contact with the bottom and top plates. Each foil segment comprises a substrate having a thickness of about 7.5-50 microns, opposing front and back substrate surfaces and a series of spaced alternating n-type and p-type thermoelectric legs disposed in parallel arrangement on the front substrate surface. Each of the n-type and p-type legs is formed of a bismuth telluride-based thermoelectric material having a thickness of about 5-100 microns, a width of about 10-100 microns and a length of about 100-500 microns. The alternating n-type and p-type thermoelectric legs are electrically connected in series and thermally connected in parallel such that a temperature differential between the bottom and top plates results in the generation of power.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS [0001] (Not Applicable) STATEMENT RE: FEDERALLY SPONSORED RESEARCH / DEVELOPMENT [0002] (Not Applicable) BACKGROUND OF THE INVENTION [0003] The present invention pertains generally to thermoelectric devices and, more particularly, to a self-sufficient, low power thermoelectric generator having a compact size and a relatively high voltage output which is specifically adapted to be compatible with microelectronic devices. [0004] The increasing trend toward miniaturization of microelectronic devices necessitates the development of miniaturized power supplies. Batteries and solar cells are traditional power sources for such microelectronic devices. However, the power that is supplied by batteries dissipates over time requiring that the batteries be periodically replaced. Solar cells, although having an effectively unlimited useful life, may only provide a transient source of power as the sun or other light sources may not always be available. [0005]...

AI Technical Summary

Benefits of technology

[0017] Each one of the foil segments has a front substrate surface and a back substrate surface opposing the front substrate surface. The foil segments are arranged such that the back substrate surface of a foil segment faces the front substrate surface of an adjacent foil segment. The spaced, alternating n-type and p-type thermoelectric legs are disposed in parallel arrangement to each other on the front substrate surface. Each of the n-type and p-type thermoelectric legs are formed of the thermoelectric material generally having a thickness in the range of from about 5 microns (μm) to about 100 μm, with a preferable thickness of about 7 μm. The front substrate surface may have a surface roughness that is smoother than that of the back substrate surface in order to enhance the repeatability of forming the n-type and p-type thermoelectric legs on the front substrate surface.

Problems solved by technology

However, the power that is supplied by batteries dissipates over time requiring that the batteries be periodically replaced.

Solar cells, although having an effectively unlimited useful life, may only provide a transient source of power as the sun or other light sources may not always be available.

Although the module of the reference overcomes the problems of electrical shorts between adjacent thermoelectric legs, the device of the reference requires numerous manufacturing steps and is therefore costly.

Although such devices succeeded in reducing the cross section of these bulk material bismuth telluride thermocouples to a sufficiently small size, the extreme difficulty in handling and fabricating these bismuth telluride-type thermocouples from bulk material translates into extremely high production costs leading to a very high cost of the final product.

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