A Thermographic Measurement Approach to Assess Supercapacitor Electrical Performances

Abstract

This paper describes a proposal for the qualitative assessment of condition of supercapacitors based on the conducted thermographic measurements. The presented measurement stand was accompanied by the concept of methodology of performing tests. Necessary conditions, which were needed to minimize the influence of disturbing factors on the performance of thermal imaging measurements, were also indicated. Mentioned factors resulted from both: the hardware limitations and from the necessity to prepare samples. The algorithm that was used to determine the basic parameters for assessment has been presented. The article suggests to use additional factors that may facilitate the analysis of obtained results. Measuring the usefulness of the proposed methodology was tested on commercial samples of supercapacitors. All of the tests were taken in conjunction with the classical methods based on capacitance (C) and equivalent series resistance (ESR) measurements, which were also presented in the paper. Selected results presenting the observed changes occurring in both: basic parameters of supercapacitors and accompanying fluctuations of thermal fields, along with analysis, were shown. The observed limitations of the proposed assessment method and the suggestions for its development were also described.

Methods of Assessing Degradation of Supercapacitors by Using Various Measurement Techniques

“…The tested samples were also coated with a graphite layer (Graphite 33 from Contact Cheme). In addition, a reference field was The applied thermographic system for measurement of supercapacitors was presented in more detail in [26,27]. In the conducted research, no modifications were made to the measurement procedures proposed in [25].…”

“…In addition, a reference field was introduced in the field of view of the camera. Thermographic measurements series of N thermograms were made in accordance with the time interval of 60 s as suggested in [27]. The obtained data was collected in a matrix consisting of N measurements having a size of 388 × 288 data of observed temperatures.…”

“…The obtained data was collected in a matrix consisting of N measurements having a size of 388 × 288 data of observed temperatures. The data on the thermographic assessment of tested samples was analyzed in an off-line manner according to the algorithm presented in [27]. It enabled the parameters supporting the assessment of the measurements to be obtained.…”

“…The data presented in the paper refers to the determined values-maximum temperature increment (ΔTMax) of the observed surface during the charging/discharging process. The use of other parameters proposed in [27] for the evaluation of supercapacitors is presented in [26]. The block diagram of the noise measurement set-up is shown in Figure 3.…”

“…Noise level depends on working conditions as well as defects or degradation existing in the tested structures. It is often used to assess the quality of various objects and devices [27].…”