Composite Liquid Hydrogen Tank Ports for Leak-Tight Cryogenic Storage

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

The challenges of using hydrogen fuel in aircraft include its low power density, increased volume and weight requirements due to cryogenic storage, and the need for a storage tank that minimizes hydrogen leakage.

Innovation Solution

The development of a composite hydrogen storage tank with integrated, seamless ports formed using reinforcing fiber tows and a matrix material, incorporating a hydrogen barrier layer to prevent leakage and maintain cryogenic temperatures.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If traditional storage tanks are used for liquid hydrogen, then hydrogen can be stored, but hydrogen leakage occurs and cryogenic temperatures cannot be maintained

Engineering Contradiction:
Improvehydrogen containmentVSAvoidhydrogen leakage
Core Design Contradiction:
ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The storage tank uses a composite structure consisting of a liner layer (metal or polymer) in contact with liquid hydrogen, an intermediate layer, and an outer structural layer (fiber-reinforced composite). This multi-material composite design provides both chemical compatibility with hydrogen and mechanical strength, preventing hydrogen leakage while maintaining cryogenic temperatures.

Inventive Principle:
Principle #40Composite materials

Solution Approach 2:

Different regions of the tank wall have different material properties optimized for their specific functions: the inner liner provides hydrogen compatibility and sealing, the intermediate layer provides thermal insulation and stress distribution, and the outer layer provides structural strength. This localized material optimization prevents leakage and maintains temperature.

Inventive Principle:
Principle #3Local quality

2Quantity of substance

If cryogenic storage is implemented for liquid hydrogen, then hydrogen can be stored, but the volume and weight requirements increase

Engineering Contradiction:
Improveliquid hydrogen storageVSAvoidstorage tank weight
Core Design Contradiction:
Quantity of substanceVSWeight of moving object

Solution Approach 1:

The fiber-reinforced composite structural layer provides high strength-to-weight ratio, enabling the tank to withstand cryogenic pressures while minimizing weight. The composite structure allows thin-walled design that maintains structural integrity at low temperatures without excessive weight penalty.

Inventive Principle:
Principle #40Composite materials

Solution Approach 2:

The tank is designed to operate at cryogenic temperatures (around -253°C for liquid hydrogen), which changes the physical properties of the materials. The composite materials are selected to maintain their mechanical properties at these extreme temperatures, enabling lightweight design while storing liquid hydrogen.

Inventive Principle:
Principle #35Parameter changes

3Quantity of substance

If cryogenic storage is implemented for liquid hydrogen, then hydrogen can be stored, but the volume requirements increase

Engineering Contradiction:
Improveliquid hydrogen storageVSAvoidstorage tank volume
Core Design Contradiction:
Quantity of substanceVSVolume of moving object

Solution Approach 1:

The composite structural layer enables efficient use of tank volume by providing high strength with minimal wall thickness. This allows the majority of the tank volume to be dedicated to hydrogen storage rather than structural material, maximizing the quantity of liquid hydrogen that can be stored in a given space.

Inventive Principle:
Principle #40Composite materials

4Reliability

If seamless ports are integrated into the composite tank, then hydrogen leakage is minimized, but manufacturing complexity increases

Engineering Contradiction:
Improvehydrogen containmentVSAvoidport integration
Core Design Contradiction:
ReliabilityVSEase of manufacture

Solution Approach 1:

The ports are integrated seamlessly into the composite tank structure during the same manufacturing process (autoclave curing). The port fittings are embedded within the fiber-reinforced composite layer, creating a monolithic structure without separate joints or connections that could leak hydrogen. This merging of components eliminates potential leakage paths.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The port fittings are positioned and prepared before the final autoclave curing process. The fiber reinforcement layers are laid up around the port fittings in advance, and then the entire assembly is cured as one piece. This preliminary arrangement ensures proper integration and eliminates the need for post-manufacturing assembly that could create leakage risks.

Inventive Principle:
Principle #10Preliminary action

Data Source

PatentEP4578639A1Method of manufacturing a composite storage tank for liquid hydrogen
Publication Date: 2025.07.02 GENERAL ELECTRIC CO
  • EP4578639A1 patent drawingFigure 1
  • EP4578639A1 patent drawingFigure 2
  • EP4578639A1 patent drawingFigure 3

AI summary

A method of manufacturing a composite storage tank (212) for liquid hydrogen. The method includes placing a port (300) on a layup tool (340). The port (300) includes a flange portion (310) and a conduit portion (320) projecting from the flange portion (310). The conduit portion (320) includes a passage (302) extending through the conduit portion (320). The method also includes laying up a plurality of reinforcing fiber tows (342) on the layup tool (340) to integrate the flange portion (310) of the port (300) with the plurality of fiber tows. The plurality of fiber tows is laid up to form at least a portion of a preform including the port (300) for the composite storage tank (212). The method further includes introducing a matrix material to the preform and curing the preform including the matrix material to generate the composite storage tank (212).