A novel multilayer composite structured thermoelectric module with high output power

Output power is a vital criterion for evaluating the heat-electricity conversion capability of thermoelectric power generators (TEGs). This study for the first time proposes a novel (Bi,Sb)(2)Te-3-based multilayer composite structured thermoelectric module (MCTEM) that can achieve high power output. Parallel heat transfer and electrical parallel connection are simultaneously achieved in an n-type single-leg MCTEM which is composed of several alternately stacked thermoelectric slices and inner electrodes. The extremely low inner resistance (R-in) and high current (I) are 0.03 and 12.7 times those measured in a single-leg traditional module, respectively, and then a maximum output power (P-max) of 5.8 mW is achieved at Delta T = 35 degrees C. The effect of the slice number on module performance has been investigated, and the optimal P-max for n- and p-type single-leg MCTEMs has been achieved when using 3 slices. Based on the optimized single-leg MCTEMs mentioned above, a pi-type MCTEM has been designed to improve the output voltage (V) and further enhance the P-max. The pi-type MCTEM achieves a high V of 3.1 mV while maintaining a low R-in of 0.94 m Omega and a large I value of 3.3 A, and then a P-max of 10.5 W is obtained which is 4.2 times that of the traditional module at Delta T = 35 degrees C. This new design of a MCTEM provides enlightenment for fabrication and commercialization through the development of high-power TEGs.