Abstract: A method includes preparing a thermoelectric material including p-type or n-type material and first and second caps including transition metal(s). A powder precursor of the first cap can be loaded into a sintering die, punches assembled thereto, and a pre-load applied to form a first pre-pressed structure including a first flat surface. A punch can be removed, a powder precursor of the p-type or n-type material loaded onto that surface, the punch assembled to the die, and a second pre-load applied to form a second pre-pressed structure including a second substantially flat surface. The punch can be removed, a powder precursor of the second cap loaded onto that surface, the first punch assembled to the die, and a third pre-load applied to form a third pre-pressed structure. The third pre-pressed structure can be sintered to form the thermoelectric material; the first or second cap can be coupled to an electrical connector.

Abstract: Apparatus and method for generating electricity. The apparatus includes one or more first components configured to extract heat from at least a first fluid flow at a first temperature to one or more devices configured to convert thermal energy to electric energy. The first fluid flow is in a first direction. Additionally, the apparatus includes one or more second components configured to transfer heat from the one or more devices to at least a second fluid flow at a second temperature. The second temperature is lower than the first temperature, and the second fluid flow is in a second direction. Each first part of the first fluid flow corresponds to a first shortest distance to the one or more devices, and the first shortest distance is less than half the square root of the total free flow area for a corresponding first cross-section of the first fluid flow.

Abstract: A thermoelectric generator includes a tapered inlet manifold including first and second non-parallel sides; first and second pluralities of outlet manifolds; and thermoelectric generating units (TGUs) each including a hot-side heat exchanger (HHX) with inlet and outlet; a cold-side heat exchanger (CHX); and thermoelectric devices arranged between the HHX and CHX. The inlets of some of the HHXs receive exhaust gas from the first side of the tapered inlet manifold and the outlets of those HHXs are coupled to outlet manifolds of the first plurality of outlet manifolds. The inlets of other of the HHXs receive exhaust gas from the second side of the tapered inlet manifold and the outlets of those HHXs are coupled to outlet manifolds of the second plurality of outlet manifolds. The thermoelectric devices can generate electricity responsive to a temperature differential between the exhaust gas and the CHXs.

Abstract: Apparatus and method for generating electricity. The apparatus includes one or more first components configured to extract heat from at least a first fluid flow at a first temperature to one or more devices configured to convert thermal energy to electric energy. The first fluid flow is in a first direction. Additionally, the apparatus includes one or more second components configured to transfer heat from the one or more devices to at least a second fluid flow at a second temperature. The second temperature is lower than the first temperature, and the second fluid flow is in a second direction. Each first part of the first fluid flow corresponds to a first shortest distance to the one or more devices, and the first shortest distance is less than half the square root of the total free flow area for a corresponding first cross-section of the first fluid flow.

Abstract: A method includes preparing a thermoelectric material including p-type or n-type material and first and second caps including transition metal(s). A powder precursor of the first cap can be loaded into a sintering die, punches assembled thereto, and a pre-load applied to form a first pre-pressed structure including a first flat surface. A punch can be removed, a powder precursor of the p-type or n-type material loaded onto that surface, the punch assembled to the die, and a second pre-load applied to form a second pre-pressed structure including a second substantially flat surface. The punch can be removed, a powder precursor of the second cap loaded onto that surface, the first punch assembled to the die, and a third pre-load applied to form a third pre-pressed structure. The third pre-pressed structure can be sintered to form the thermoelectric material; the first or second cap can be coupled to an electrical connector.

Abstract: A method includes preparing a thermoelectric material including p-type or n-type material and first and second caps including transition metal(s). A powder precursor of the first cap can be loaded into a sintering die, punches assembled thereto, and a pre-load applied to form a first pre-pressed structure including a first flat surface. A punch can be removed, a powder precursor of the p-type or n-type material loaded onto that surface, the punch assembled to the die, and a second pre-load applied to form a second pre-pressed structure including a second substantially flat surface. The punch can be removed, a powder precursor of the second cap loaded onto that surface, the first punch assembled to the die, and a third pre-load applied to form a third pre-pressed structure. The third pre-pressed structure can be sintered to form the thermoelectric material; the first or second cap can be coupled to an electrical connector.

Abstract: A method includes preparing a thermoelectric material including p-type or n-type material and first and second caps including transition metal(s). A powder precursor of the first cap can be loaded into a sintering die, punches assembled thereto, and a pre-load applied to form a first pre-pressed structure including a first flat surface. A punch can be removed, a powder precursor of the p-type or n-type material loaded onto that surface, the punch assembled to the die, and a second pre-load applied to form a second pre-pressed structure including a second substantially flat surface. The punch can be removed, a powder precursor of the second cap loaded onto that surface, the first punch assembled to the die, and a third pre-load applied to form a third pre-pressed structure. The third pre-pressed structure can be sintered to form the thermoelectric material; the first or second cap can be coupled to an electrical connector.