Development of novel hydrogen storage materials by controlling ion conductivity

2019 Fiscal Year Final Research Report

• Project/Area Number: 17K14827
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Structural/Functional materials
• Research Institution: Hokkaido University
• Principal Investigator: ISOBE Shigehito 北海道大学, 工学研究院, 准教授 (10564370)
• Project Period (FY): 2017-04-01 – 2020-03-31
• Keywords: イオン電導 / 添加物

Outline of Final Research Achievements

In this study, we developed hydrogen storage materials with large capacity represented by inorganic hydrides such as Li-amide / imide. As a result, it was found that the addition of lithium titanate to Li amide / imide system improved the rate of hydrogen release reaction, and this improvement was strongly correlated with the improvement in Li ion conductivity. On the other hand, by adding lithium titanate to the alanate-based material, the hydrogen release reaction rate could be improved, but almost no correlation was found with the improvement in lithium ion conductivity. That is, it has been found that the rate of the hydrogen release reaction of the inorganic hydride is different from each other, and that the addition of lithium titanate is effective when the diffusion of lithium ions is rate-limiting.

Free Research Field

材料工学

Academic Significance and Societal Importance of the Research Achievements

無機系水素化物の水素放出反応の律速はそれぞれ異なり，リチウムイオンの拡散が律速となる場合にチタン酸リチウム等の添加物が有効であるという知見が得られた。特に，リチウムアミドイミド系材料においてその効果が顕著であった。一方，リチウムマグネシウムアミドイミド系材料では，リチウムイオンの拡散を促進する添加物は有効でなく，KHなど他の添加物の有効性が示された。このKHの効果は，中間生成物の生成の有無が強く関係するということが見いだされた。これらの知見をもとに，適材適所の材料設計指針を立てることができると考えられる。