Fraunhofer IFAM develops advanced manufacturing for cryogenic CFRP hydrogen tanks
Researchers have created new methods for producing large-scale, double-walled cryogenic hydrogen tanks from carbon fiber-reinforced plastic (CFRP), focusing on surface preparation, barrier layers, and automated assembly.
Fraunhofer IFAM, in collaboration with HYTANK project partners, has developed resource-efficient manufacturing and joining technologies for large-format, double-walled hydrogen tanks constructed from CFRP. This integrated approach covers surface pretreatments, functional barrier layers, and automated production, including machining and adhesive-bonding assembly, aiming for lighter, leak-tight, and cryogenically reliable tank structures.
Liquid hydrogen (LH₂) is a potential fuel for future aircraft, but the tanks required must be exceptionally lightweight, permanently leak-tight, and structurally sound at temperatures as low as -253°C (-423°F), while withstanding significant mechanical and thermal stresses. CFRP offers favorable properties, but its application demands sophisticated design and manufacturing processes, particularly concerning cryogenic conditions, pressure loads, and material combinations.
The HYTANK project specifically addressed these challenges by focusing on key process steps. This included the functionalization of surfaces to ensure reliable adhesion for subsequent coating systems, a critical factor for the performance of cryogenic tanks. The research aimed to develop a combined pretreatment and coating process to enhance the barrier properties of the CFRP structure, thereby stabilizing the vacuum between the inner and outer shells of double-walled tanks.
Significant effort was placed on developing barrier layers to reduce gas permeability in polymer-based tank systems. These layers are designed to minimize hydrogen leakage and prevent the ingress of atmospheric gases like oxygen or moisture. This dual function enhances operational safety and helps maintain the crucial heat-insulating vacuum in double-walled cryogenic tank designs.
This development by Fraunhofer IFAM addresses critical manufacturing hurdles for cryogenic hydrogen storage. By advancing surface pretreatment and barrier layer technologies for CFRP, it enables the production of lightweight, robust tanks essential for applications like aerospace. The focus on automation and leak-tightness is key to realizing the potential of liquid hydrogen as a sustainable fuel source, aligning with broader additive manufacturing goals for high-performance, demanding environments.
Edited by the news editor with AI from the original report — please refer to the original source.