Evaluation of Temperature Influence on Electrochemical Processes Occurring in a Lithium-Ion Supercapacitor with the Use of Dynamic Electrochemical Impedance Spectroscopy

Abstract

In order to obtain the full impedance characteristics of a lithium-ion capacitor as a function of temperature, the authors proposed the use of dynamic electrochemical impedance spectroscopy. Impedance tests were carried out under wide range of dynamic temperature changes for lithium-ion supercapacitors. Significant differences in electrochemical processes were observed as a result of working temperature. Moreover, the quality of fitting of the equivalent circuits most frequently used in impedance analysis of lithium-ion capacitors was discussed. The proposed methodology allows for a comprehensive characterization of the performance of these devices and provides key information for their optimization in wide range of operations.

Keywords

• lithium-ion capacitor
• dynamic impedance measurements
• optimization
• temperature