High-vacuum measuring system for accurate characterization of thermoelectric cooling modules

Peltier cells are Thermoelectric Coolers (TEC) used as solid-state heat-pumps in a wide range of applications, from thermal management of electronic devices to biomedical sector. Each application requires specific operating condition of the TEC module; therefore, a proper characterization is essential to optimize its performance within an energy system. The literature lacks a unified characterisation procedure and the characteristic curves provided by manufacturers do not account for all possible applications. This paper presents an experimental setup that replaces traditional insulators with high-vacuum thermal insulation, effectively eliminating unwanted heat losses and ensuring one-dimensional heat transfer through the TEC module. The experimental setup is suitable for different module geometries, and it improves the accuracy of TEC characterisation. A 20 x 20 mm2 TEC module was tested in high vacuum and in ambient air condition. The cooling power was measured and plotted as a function of the temperature difference between the hot and the cold side of the module for two applied currents. The experimental cooling power is measured with an uncertainty of +/- 0.10 W showing close agreement to the characteristic curves provided by the manufacturer only in HV conditions. The proposed vacuum-based measurement station aims to provide a standardized method for determining the characteristic curves of a TEC module for operating conditions that may differ from those of the datasheet, and with a lower uncertainty.