Electro-thermal analysis of Electric Double-Layer-Capacitors

Abstract

Electric Double Layer Capacitors (EDLCs) operate between rechargeable batteries and electrolytic capacitors with respect to energy and power performance. Prediction of internal heating due to discharge and charge current cycles is one of key elements for producing reliable and safe devices with long cycle-life. A calorimetric technique was developed for measuring the heat generation rates of EDLCs under cycling. The as developed technique is described. The heat generation rates were measured on carbon cells as a function of current cycles. Thermal measurements were found in quite good agreement with a porous electrode model of double layer capacitance describing the charging mechanisms. Calculations were performed after estimating the electrical properties of the cell by fitting the dynamic cell voltage. Investigations have conducted to a better understanding of the electro-thermal behavior of EDLCs.

A Thermographic Measurement Approach to Assess Supercapacitor Electrical Performances

“…The constant current charging/discharging method that is used in this test, despite the necessity of long-term observation, is most closely related to the actual operating conditions of the capacitors and is subjected to fluctuations in the temperature field of the tested capacitor due to its operating conditions. In supercapacitors' tests, calorimetric systems are generally used to determine maximum temperature increments, however, despite their high accuracy, they do not allow the heterogeneity of the sample to be displayed as described in articles [3,4,17]. Throughout tests, in which the proposed method was used, the following parameters of the power supply system were also monitored:…”

“…The observed fluctuations of this field arise mainly from those modifications, which, as a result of the degradation processes, are changing (usually the increase of the ESR value along with the degradation of the tested structure). Construction, properties, substitute models of supercapacitors, and modelling of temperature flows were inter alia discussed in the papers [2][3][4][5][6]. Suggested in the article proposal for using thermographic techniques in order to evaluate the condition of supercapacitors does not exhaust the subject.…”

A Review on Electrothermal Modeling of Supercapacitors for Energy Storage Applications

“…understanding of electrochemical process [94][95][96][97]. In [67], calorimetric technique is used to measure heat generated inside an EDLC under cycling.…”

A Way for Measuring the Temperature Transients of Capacitors

“…According to the information found in the literature [4] the BaTiO3 is a commonly used ceramics to create X7R grade ceramic capacitors. As a base approximation we supposed that this material was used as dielectric layer and used the material properties suggested by the referenced paper.…”

“…In order to be able to take these effects into account the thermal resistance between the surrounding components and the capacitor (the transfer resistances) and the thermal resistance between the region of the capacitor where the heat is generated and the environment (the self-resistance) should all be characterized For thermal engineering of discrete capacitors simulation is the primary method of investigation and characterization [1] although analytical calculations based on simplified models are sometimes also provided in application notes [2][3][4]. Experimental results are only rarely mentioned in relevant papers or datasheets, although the numerical results should always be verified using experiments.…”