Guidelines for supercapacitor electrochemical analysis: A comprehensive review of methodologies for finding charge storage mechanisms

Driven by the growing demand for high-power energy storage devices, supercapacitors (SCs) have been a notable trend in recent years owing to their exceptional power capabilities and remarkable cycle life, making them exceptionally well-suited for transportation and renewable energy generation applications. In the past decade, intensive research endeavors have focused on advanced electrode materials and innovative cell designs, with the aim of enhancing SC performance through diverse charge storage mechanisms. Therefore, this paper is dedicated to exploring various methodologies and the recent advancements made in characterizing charge storage mechanisms within SCs. It delves into a field of electroanalytical techniques, including Electrochemical Impedance Spectroscopy, Galvanostatic Charge-Discharge, Step Potential Electrochemical Spectroscopy, and Cyclic Voltammetry. It also examines related analytical methods and categorizes them into quantitative and qualitative approaches. The paper provides a comprehensive review, outlining the principles behind these methodologies while elucidating their respective advantages and limitations. Furthermore, this review places significant emphasis on formulating guidelines for the application of charge storage mechanism characterization approaches. By fostering an understanding of these mechanisms, researchers can unlock new possibilities in fields such as renewable energy, electric vehicles, portable electronics, and grid energy storage, ultimately contributing to more efficient and sustainable energy storage solutions.