Advancements and Innovations in Low-Temperature Hydrogen Electrochemical Conversion Devices Driven by 3D Printing Technology

3D printing, as a versatile additive manufacturing technique, offers high design flexibility, rapid prototyping, minimal material waste, and the capability to fabricate complex, customized geometries. These attributes make it particularly well-suited for low-temperature hydrogen electrochemical conversion devices—specifically, proton exchange membrane fuel cells, proton exchange membrane electrolyzer cells, anion exchange membrane electrolyzer cells, and alkaline electrolyzers—which demand finely structured components such as catalyst layers, gas diffusion layers, electrodes, porous transport layers, and bipolar plates. This review provides a focused and critical summary of the current progress in applying 3D printing technologies to these key components. It begins with a concise introduction to the principles and classifications of mainstream 3D printing methods relevant to the hydrogen energy sector and proceeds to analyze their specific applications and performance impacts across different device architectures. Finally, the review identifies existing technical challenges and outlines future research directions to accelerate the integration of 3D printing in next-generation low-temperature hydrogen energy systems.