A device designed for research of heat phenomena occurring in chemical power sources (CPS) is described. The device includes two functional blocks: electrochemical and calorimetrical, operating under single control, which allows simultaneously performing electrochemical and calorimetric measurements. The calorimetric block is a heat flow calorimeter. The calorimetric chamber design provides the possibility of studying thermal processes in laboratory electrochemical cells and CPS of planar, disk, and prismatic design. The absolute measurement error of the heat flow is ±50 μW at the resolution of 1 μW. The operating temperature range of the calorimetric chamber is 0–90°C. The basis of the electrochemical block is a module of a four–range potentiostat–galvanostat. The maximum polarizing current of the potentiostat is ±200 mA at the maximum voltage on the auxiliary electrode of ±10 V. Multiuser remote access from the user computers over Ethernet to the device is provided for control and treatment of experimental data. Digital deconvolution filters allowing to compensate the response rate of the heat flow meter are used for processing primary data of calorimetric measurements.