Overview on the applications of three-dimensional printing for rechargeable lithium-ion batteries

Rechargeable lithium-ion battery (LIB) is a kind of electrochemical energy storage and conversion device with both high energy and power densities. The real application of various advanced LIBs (e.g., three-dimensional (3D) LIBs, flexible, wearable or customized LIBs) and integrated manufacturing of LIBs or LIB-powered devices depend on specific fabrication processes. However, conventional commercialized manufacturing techniques with sophisticated and expensive processes are far away from the facile, cost-effective and free-form fabrication demands. Additive manufacturing, usually known as 3D printing, is an ideal solution. This technology enables practical freedom of fabricating objects with well-controlled complex geometry through a layer-by-layer deposition process, independent of any templates. Almost all kinds of materials, from nanoscale to macroscale, can be used for 3D printing. In this work, we review the application advance of 3D printing in the field of LIBs. The fundamental concepts of representative 3D printing techniques are presented first, including the operation principles, requirements for raw printing materials and manufacturing accuracy of different 3D printing techniques. Then the applications are discussed at both component and package levels. Finally, the methodology, challenges and future perspectives of exploiting 3D printing for real applications in LIBs are presented. All the applications of 3D printing discussed herein can provide us with right directions of better energy conservation and conversion.