Non-thermal plasma (NTP), as an advanced technology capable of efficiently synthesizing and modifying materials at near-ambient temperatures, has attracted significant attention in the field of energy materials in recent years. Owing to its high electron temperature and low bulk gas temperature, NTP can significantly enhance the electrochemical performance of electrode materials by creating vacancies, enabling heteroatom doping, and adjusting multiscale defects such as porosity and surface roughness, while preventing thermal damage. The plasma-material surface interaction is a complex system involving mutual influences between the plasma and the material. An in-depth understanding of this mechanism is essential for achieving precise control over defect type, density, and spatial distribution by modifying NTP. This paper systematically summarizes recent advances in the application of NTP for etching and doping energy materials, with special emphasis on the formation mechanisms of defects and their functional role in plasma-surface interactions. The plasma sheath effects, defect generation pathways, and the influence of material morphology on local plasma behavior are discussed in detail. Finally, this paper outlines prospects for future research on NTP-modified energy materials.