Electrochemical energy storage technologies have a profound influence on daily life, and their development heavily relies on innovations in materials science. Recently, high-entropy materials have attracted increasing research interest worldwide. In this perspective, we start with the early development of high-entropy materials and the calculation of the configurational entropy. Then, we summarize the recent progress in material design and application using the high-entropy strategy, especially highlighting rechargeable battery materials. Finally, we discuss the potential directions for the future development of high-entropy energy materials.