Additive Manufacturing of Energy Functional Materials: Structural Batteries, Thermoelectric, and Magnetic Alloys

Additive Manufacturing (AM) has emerged as a transformative paradigm in materials engineering, enabling the fabrication of geometrically complex and functionally integrated materials that are not achievable through conventional processing routes. Among its most promising applications is the development of energy functional materials, including structural batteries, thermoelectric materials, and magnetic alloys. These materials are designed to simultaneously perform mechanical and energy-related functions, thereby enabling weight reduction, system integration, and improved efficiency in advanced engineering applications. This paper presents a comprehensive and critical review of AM techniques for the fabrication of energy functional materials, with emphasis on the interplay between processing conditions, microstructural evolution, and functional performance. The review systematically discusses Powder Bed Fusion, Directed Energy Deposition, and hybrid AM techniques, highlighting their advantages and limitations in controlling material properties. Special attention is given to multifunctional design challenges, such as balancing mechanical strength with electrochemical performance in structural batteries, optimizing thermoelectric efficiency, and tailoring magnetic properties through microstructural engineering. Furthermore, emerging trends such as multi-material printing, functionally graded architectures, and digital design strategies are explored. The review concludes by identifying key research gaps and future directions, emphasizing the role of AM in advancing next-generation energy systems.