Large external Delta T and cooling power densities in thin-film Bi2Te3-superlattice thermoelectric cooling devices
Experimental I-V-Tc-T data of thin-film superlattice thermoelectric modules is used to determine the internal T, cross-plane Seebeck coefficient, effective thermal interface resistance, device ZT, and Qmax. We demonstrate 55 K of external cooling at 300 K (Tcmin=244.8 K), with an estimated heat pumping capacity of 128 W/cm2. The average ZT300 for the best superlattice devices is 0.75, compared to 0.66 for a bulk BixSb2–xTe3/Bi2SexTe3–x device. Our model indicates a significantly higher internal T occurs across the active thermoelectric element, which was verified using buried thermocouples.