New tank concepts for liquid hydrogen

Increasing the storage and transport efficiency for liquid hydrogen in steel fiber composite tanks by thermally sprayed TBC coatings (LH2 Tanks)

There is currently little experience with maritime production, offshore storage and transportation of large quantities of liquid hydrogen (LH2) due to the developing market. The tank designs relate to standard applications for onshore storage and transportation with vacuum-insulated, double-walled constructions made of austenitic stainless steel, which have comparatively high thermal diffusivity and conductivity as well as increased weight. This currently reduces efficiency due to the increased boil-off and the unfavorable gravimetric storage density.

© Fraunhofer IGP
Thermal diffusivity of thermally sprayed TBC coating and tank material in comparison


he complex structure of LH2 tanks with inner and outer vessel, usually made of low-temperature austenitic steel with a comparatively high thermal conductivity (λ = 15 - 20 W / m K) and diffusivity (3.6 - 4.1 mm² / s) requires a high tank weight. This has a negative effect on the ratio of cargo weight to means of transport weight.

Objective and solution

New tank concepts are therefore required for the maritime production and transportation of LH2. Here, innovative technical approaches from the aerospace industry (fiber windings) and for high-temperature applications (thermal barrier coatings "TBC") are adopted and combined. With the help of fiber reinforcements applied in the circumferential direction in the cylindrical part on the outside of the inner tank, structural support for the steel tank and consequently a reduction in the wall thickness can be achieved. The application of thermally sprayed TBC coatings on the inside of the inner tank using innovative materials is promising in terms of improving the insulation properties and shows, for example, a thermal diffusivity that is two times lower than the tank material.


The hybrid steel FRP tanks developed for LH2 transport can supplement the LH2 storage market and thus open up new business areas for SMEs in the field of fiber winding. The investigated material properties of thermally sprayed TBCs (insulation, cryogenic conditions), which have been insufficiently researched to date, and the knowledge gained about the connection of fibre winding to steel tanks at cryogenic temperatures also form a basis for the design of weight-optimized LH2 tanks and the development of new fields of application for all players in the field of hydrogen production, logistics and end use.

Project partners

  • Fraunhofer CML
  • Hochschule Stralsund
  • Leibniz Universität Hannover
  • Technische Universität Hamburg Harburg
  • Air Liquide Deutschland GmbH
  • Apex Energy Teterow GmbH
  • BaltiCo GmbH
  • Berolina Metallspritztechnik Wesnigk GmbH
  • DURUM Verschleißschutz GmbH
  • Hanseatic Rohr GmbH
  • Kongstein GmbH
  • Linde plc
  • OT Oberflächentechnik GmbH & Co. KG
  • Putzier Oberflächentechnik GmbH
  • Schwanner GmbH


The research project IGF 39 LBR 1 / Increasing the storage and transport efficiency for liquid hydrogen in steel fiber composite tanks by thermally sprayed TBC coatings (LH2 tanks) from the Research Association for steel Application (FOSTA), Düsseldorf, is supported by the Federal Ministry of Economic Affairs and Climate Action, the German Federation of Industrial Research Associations (AiF) as part of the programme for promoting industrial cooperative research (IGF) on the basis of a decision by the German Bundestag. The project is carried out at Fraunhofer IGP in the framework of the overall project entitled Offshore Wind Energy Systems for Hydrogen Supply. We thank for the funding, the cooperation with other research institutes and for the input by the participating companies.