Based on direct-current transient Harman method,an integrated characterization system of thermoelectric device’s performance is established.The overall properties of thermoelectric modules with sandwiched structures are experimentally investigated,including Seebeck coefficients,figures of merit(ZT),electrical and thermal conductivities.Experiment results reveal that ZT values of thermoelectric modules are smaller than those of commercial bismuth telluride(Bi2Te3)modules.In contrast,Seebeck coefficients are significantly larger than traditional thermoelectric device’s values.Meanwhile,both electrical and thermal conductivities are greater compared with literature data.Our results have proposed a feasible and economical way that can potentially increase Seebeck coefficients as to bulk Bi2Te3materials without significant deterioration to the nature of Peltier effect.