Review of the Electrochemical Double Layer Theory and Its Applications in Battery Electrode Materials

The interface plays a critical role in electrochemical systems, driving the development of various theories to investigate properties at nanoscale and microscale levels, including the electrictrochemical double layer (EDL) theory and continuum theory. However, the application of EDL theory within the realm of battery electrode materials has not been clearly defined according to material type. The diverse range of materials and their intricate interactions with interface theories often lead to misunderstandings. This review meticulously outlines the origins and principles of the EDL theory. Additionally, it categorizes battery electrode materials into two main groups: semiconductors and conductors. A comprehensive examination is presented on the implementation of EDL and other interface theories, accompanied by a comparative evaluation of the fundamental models and experiments described. The review also explores the potential advancements of EDL and other interface theories, as well as their application in electrode materials. This exhaustive review serves as an invaluable resource for scholars in electrochemistry and materials science, aiding in their understanding of interface theories, their scope of applicability, and the integration of these theories with practical experimental approaches.