Thermoelectric (TE) generators have very important applications, such as emerging automotive waste heat recovery and cooling applications. This study investigates how thermal conductivity, seebeck coefficient, and resistivity of bismuth telluride changes with increasing isothermal aging. The thermal conductivity was tested with the Transient Plane Source (TPS) method. Both bismuth telluride n and p type were tested for 2 wk, 8 wk, 6 mo, 1 yr, and 2 yr of isothermal aging at 240 degrees Celsius. The ...