Liquefied hydrogen-related technology has developed along with space development. Liquefied hydrogen is now being supplied to various industries in addition to rockets. In 1978, Iwatani started operation of Japan’s first commercial liquefied hydrogen plant, and in 2006 we started operation of a large-scale liquefied hydrogen plant, supplying all of Japan. We have also participated in national projects related to liquefied hydrogen, such as the Sunshine Project, and accumulated hydrogen technology. This paper describes the status of liquefied hydrogen production, transportation, and utilization technology, and our efforts to date Our efforts to date regarding liquefied hydrogen.

Showa Denko K.K. (SDK) Kawasaki plant was established in 1930, and started hydrogen business in 1931. SDK delivers hydrogen through pipelines and compressed hydrogen via cylinders, cadles, and trailers. The pipeline was installed during the construction of the industrial complex in the Kawasaki coastal area. From 2015 to March 2022, a demonstration project by the Ministry of the Environment was conducted. In the demonstration project, SDK supplied hydrogen through a pipeline, and electricity and heat were provided to the hotel by a fuel cell. Most of the SDK’s pipelines are laid underground, and quality is ensured through annual safety inspections and constant cathodic protection. Expansion of the pipeline network is essential for the construction of a hydrogen society in the future. It is necessary to reduce the construction cost and deregulate the acquisition of licenses.

This article introduces some types of composite tank for liquid hydrogen. Background, features, and outline of production method for each liner-less, metal-lined, and polymer-lined composite tank are shown respectively. Adding these, two promising technologies under development, liner by electro-plating and pre-preg with liquid crystal polymer matrix, are also introduced.

This paper provides an overview of various high-pressure hydrogen containers and describes high-pressure composite containers for fuel cell vehicles (FCVs). As a method of increasing the cruising range of battery drones, a hydrogen fuel cell drone equipped with an air-cooled fuel cell has obtained special approval from the minister and has made its first flight in Japan. The small composite cylinder for mounting FC drones, which has become a hot topic recently, is explained

Hydrogen embrittlement is caused by a small amount of hydrogen in steels used under applied stress, which is a critical issue in the current era when there are growing needs to further increase the strength of steels used for instance for bolts, automotive parts, and to use steels under higher hydrogen pressure for utilizing hydrogen energy. It is desirable to establish appropriate methods to evaluate hydrogen embrittlement properties of various types of steels quantitatively for safe and secure usage of materials. Several types of evaluation methods based on stress and hydrogen concentration have been utilized so far. In this review, some evaluation methods for high strength steels using such as constant load test, slow strain rate test, conventional strain rate test, and tests using U-bend specimens and stretch-formed specimens, are explained briefly. In addition, recently developed hydrogen visualization techniques using an Ir complex and polyaniline for understanding hydrogen uptake and diffusion are introduced.