Low power thermoelectric generator

A thermoelectric generator, comprising:

• a top plate and a bottom plate disposed is spaced parallel relation to one another and having a generally circular shape;
• a spirally wound foil assembly captured between and thermally interconnecting the top and bottom plates, the foil assembly comprising a series of foil segments disposed in end-to-end relationship to one another and being electrically connected in series, each one of the foil segments comprising:
• a substrate having top and bottom edges and a thickness in the range of from about 7.5 microns to about 50 microns and including opposing front and back substrate surfaces, the substrate being formed of an electrically insulating material having a low thermal conductivity;
• a series of elongate alternating n-type and p-type thermoelectric legs disposed in spaced parallel arrangement on at least one of the front and back substrate surfaces, each of the n-type and p-type legs being formed of a Bi2Te3-type thermoelectric material having a thickness in the range of from about 10 microns to about 100 microns, each n-type and p-type thermoelectric leg having a width in the range of from about 10 microns to about 100 microns and a length in the range of from about 100 microns to about 500 microns;
• wherein each one of the p-type thermoelectric legs is electrically connected to adjacent ones of the n-type thermoelectric legs at opposite ends of the p-type thermoelectric legs such that the n-type and p-type thermoelectric legs are electrically connected in series and thermally connected in parallel.

A method of producing a foil assembly for a thermoelectric generator, comprising the steps of:

• providing substrate material having front and back substrate surfaces;
• depositing an array of n-type and p-type thermoelectric legs onto the front substrate surface;
• depositing metal bridges along at least one of the top and bottom edges of the front substrate surface;
• cutting the substrate material having the n-type and p-type thermoelectric legs, metal bridges deposited thereon in such a manner to form a plurality of foil segments;
• cutting the substrate material in such a manner to omit the n-type and p-type thermoelectric legs in order to form a plurality of connectors;
• aligning a pair of the foil segments in end-to-end relationship to form a foil joint;
• mechanically interconnecting the foil segments by bonding a pair of connectors across the foil joint on at least the front substrate surface with electrically non-conductive and thermally low conductive assembly adhesive;
• and
• electrically interconnecting the foil segments at the front substrate surface by extending electrically conductive adhesive from an endmost one of the n-type thermoelectric legs of one of the foil segments to an endmost one of the p-type thermoelectric legs of an adjacent one of the foil segments of the pair.