Controlling grain-boundary resistance of proton-conducting oxides by processing under oxidizing environments

2019 Fiscal Year Final Research Report

• Project/Area Number: 16K18232
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Inorganic materials/Physical properties
• Research Institution: National Institute for Materials Science
• Principal Investigator: MIYOSHI Shogo 国立研究開発法人物質・材料研究機構, エネルギー・環境材料研究拠点, 主任研究員 (30398094)
• Project Period (FY): 2016-04-01 – 2020-03-31
• Keywords: リチウムイオン伝導 / セラミックス / 粒界抵抗 / 空間電荷層 / 全固体電池

Outline of Final Research Achievements

In order to understand the origin of grain-boundary resistance of ion-conducting ceramics, studied was the influence of processing parameters such as pressure and oxygen activity on the grain-boundary resistance. It was found that the grain-boundary resistance, which is ascribed to the nature intrinsic to respective substance rather than extrinsic causes such as impurity and phase-segregation, depends variously depends on processing conditions. While the decisive conclusions has not been reached with respect to the fundamental origin of the intrinsic grain-boundary resistance, the knowledge on the process-dependent grain-boundary resistance will contribute to the understanding and controlling of the grain-boundary resistance.

Free Research Field

固体イオニクス

Academic Significance and Societal Importance of the Research Achievements

イオン伝導体は燃料電池や二次電池などのエネルギー変換・貯蔵デバイスを始めとする様々な応用が期待されるが，その実用形態である多結晶材料においては粒子同士の界面におけるイオン輸送抵抗が問題となるケースが多い．本研究では，次世代電池材料として期待されるリチウムイオン伝導性酸化物を対象とし，この粒界抵抗に及ぼす多結晶材料の作製条件の影響を調べることによってその本質的要因を探るとともに，粒界抵抗の低減手法の開発につながる知見を得た．