Materials Science challenges for composites cylinders in the field for H_2 energy applications

摘要

Efficient storage of hydrogen is crucial for the success of hydrogen energy markets (early markets as well as transportation market). High pressure compressed gas storage in carbon fibre composite pressure vessels is currently the most mature technology. In order to achieve required autonomy and energy density, storage at a pressure of 500 to 700 bar is necessary. Some cylinders are already certified for 700 bar working pressure. However, challenges remain to improve performance and reliability while still ensuring the safety of cylinders in service over periods of about 20 years. Durability is a key feature that defines the value of composite vessels. It is essential for the development of applications requiring long-term performance to have good understanding of long-term behaviour of the cylinder and its components under operational loads. This paper contains an overview of the behaviour of materials (composite shell, liner and boss) under mechanical and thermal loadings, focusing the analysis on Type Ⅳ composite cylinders made of polymer liner that serves as a hydrogen gas permeation barrier. The compatibility of the materials with hydrogen and degradation mechanisms observed from tests representative of service conditions are discussed. The methods to evaluate and predict the damaging process are also presented.