Technological forecasting of hydrogen storage materials using patent indicators

Hydrogen is a promising future energy carrier due to its high energetic content and sustainable appeal when produced via clean manufacturing processes. One of the technological challenges concerns its storage in a safe, compact, low mass and high gravimetric capacity manner. In this sense, many Hydrogen Storage Materials (HSM) have been investigated to house this source of energy, such as Simple Hydrides, Borohydrides, Metal-Organic Frameworks (MOFs), Alanates, AB5 Alloys, Ammonia Borane, Carbon Nanotubes and Graphene. Scientific advances aside, less attention has been paid in establishing a panorama of the technological developments in HSM. To assess the technological advances in HSM, patent analysis can be carried out using bibliometrics and text mining approaches in order to forecast the future trend of development and the main players involved in this process. In this work, we evaluated the technological life cycle stage, HSM class prominence and the role of different countries in HSM patenting. The results show that overall HSM patenting decreased after 2007, except in the case of China. On the other hand, the USA, Japan, China and the European Union (EU) were the main patenting territories. Simple Hydrides and Borohydrides were the main classes of HSM that received more attention from the USA and the EU, while Japan had a high share in Solid Solution Alloys. The life cycle stage of HSM seems to be between the first prototype market experiences and full market deployment, even though future assessment is needed to fine-tune the analysis. The developed indicators may also support the funding of new projects and decision making.