Development of a semi-solid flow battery for external regeneration of solid active materials

Research Project

Project/Area Number	17K18842
Research Category	Grant-in-Aid for Challenging Research (Exploratory)
Allocation Type	Multi-year Fund
Research Field	Fluid engineering, Thermal engineering, and related fields
Research Institution	Osaka University
Principal Investigator	Tsushima Shohji 大阪大学, 工学研究科, 教授 (30323794)
Co-Investigator(Kenkyū-buntansha)	鈴木崇弘大阪大学, 工学研究科, 助教 (90711630)
Project Period (FY)	2017-06-30 – 2019-03-31
Project Status	Completed (Fiscal Year 2018)
Budget Amount *help	¥6,240,000 (Direct Cost: ¥4,800,000、Indirect Cost: ¥1,440,000) Fiscal Year 2018: ¥1,560,000 (Direct Cost: ¥1,200,000、Indirect Cost: ¥360,000) Fiscal Year 2017: ¥4,680,000 (Direct Cost: ¥3,600,000、Indirect Cost: ¥1,080,000)
Keywords	二次電池 / スラリー / 多孔質電極 / イオン電子輸送 / 熱工学
Outline of Final Research Achievements	In this study, we focused our attention on semi-solid (slurry) flow batteries (SSFBs) as future power source for automobile applications. SSFBs have their unique architecture to potentially achieve high energy density. However, SSFBs reported so far employed electrode slurry consisting of active materials, conductive additives and liquid electrolyte that flowed through the cell. This cell architecture causes larger internal resistance due to establish less electron conducting path in the slurry electrode. In this project, a batch-type semi-solid flow battery in which electroconductive porous meshes and filters were embedded were developed for further improvement of cell performance. We successfully demonstrated this type of the cell that can be operated without flowing electrode slurry under charge and discharge conditions. Polarization curves were obtained in a full- and/or half-cell experiments and stable cycle performance was achieved.
Academic Significance and Societal Importance of the Research Achievements	本研究課題では，レドックスフロー電池とリチウムイオン二次電池の特長を最大限に活用・融合した新たな電池系を研究対象とし，固相活物質粒子の供給・充填・回収が可能でかつ，高エネルギー密度を有する新規なフロー電池の構築を目的とした．特に，導電性多孔体を電極に導入し，活物質粒子を供給・充填・回収する点で新しく，固液懸濁液（スラリー）の供給による電極構築と高効率な固相活物質粒子を用いたフロー電池を実証することができた．加えて，電気化学計測により固相活物質粒子を用いるフロー電池の過電圧要因を明らかにし，さらなる性能向上に向けた学術的課題の抽出を行った．