Non-Thermal Plasma (NTP), as an advanced technology capable of efficiently synthesizing and modifying materials under near-ambient temperature, has attracted significant attention in the field of energy materials in recent years. Owing to high electron temperature and low bulk gas temperature, NTP can significantly enhance the electrochemical performance of electrode materials by introducing vacancies, enabling heteroatom doping, and regulating multiscale defects such as porosity and surface roughness, while avoiding thermal damage. The plasma-material surface interaction is a complex system involving mutual influences between the plasma and the material. A deep understanding of this mechanism is essential for achieving precise control over defect type, density, and spatial distribution via NTP modification. This review systematically summarizes the applications of NTP in etching and doping processes for energy materials, with a particular emphasis on defect generation and its role in plasma–surface interactions. Finally, the major challenges associated with the large-scale application of NTP technology are discussed, and future perspectives are outlined.