Effective energy storage devices necessitate the development of superior electrode materials as well as an in-depth knowledge of characterization techniques. Currently, smart materials (metallic, polymeric, and nanocomposite) are considered fascinating and leading candidates in the field of energy storage applications. To test the applicability of such materials in the field of energy storage field, an in-depth knowledge of electrochemical characterization techniques is mandatory, since they aid to comprehend a substance’s fundamental electrochemistry. So, this chapter explores a range of electrochemical characterization techniques (like voltammetric techniques, galvanometric techniques, impedance measurement techniques, and additional prominent techniques) applied in electrochemical investigations. These methods collectively enable an understanding phenomenon taking place at the electrode–electrolyte boundary in an electrochemical cell. Key findings reveal that the electrochemical performance of smart materials is intrinsically linked to their structural and compositional characteristics, which can be accurately evaluated using advanced characterization techniques. Furthermore, the integration of smart nanomaterials into solid-state and flexible devices, combined with emerging trends such as real-time, in-situ characterization, multifunctional platforms, and sustainable material development, is poised to accelerate the design of next-generation energy storage systems that are more efficient, durable, and eco-friendly. This chapter highlighted methods that is applicable for analyse the electrochemical behaviour of smart materials in the field of energy storage devices.