2021 Fiscal Year Final Research Report
Control of interface structure and optimization of ionic conductivity for lithium ion batteries with high capacities
Project/Area Number |
19H02609
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Research Category |
Grant-in-Aid for Scientific Research (B)
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Allocation Type | Single-year Grants |
Section | 一般 |
Review Section |
Basic Section 29030:Applied condensed matter physics-related
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Research Institution | Kindai University (2020-2021) Doshisha University (2019) |
Principal Investigator |
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Project Period (FY) |
2019-04-01 – 2022-03-31
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Keywords | リチウムイオン電池 / 蓄電池 / シリコン負極 |
Outline of Final Research Achievements |
Silicon negative electrodes with high capacities have been developed for next-generation lithium-ion batteries. For practical use of the silicon negative electrodes, suppression of a reductive decomposition of an electrolyte is necessary to achieve a long cycle life. Silicon composite electrodes with Nafion (perfluorinated ionomers) coating demonstrated improved cycle performance. X-ray photoelectron spectroscopy analyses of the Nafion-coated electrodes revealed that Nafion decomposed reductively to form a LiF-rich surface film at the first charging and effectively suppressed the decomposition of the electrolyte. Moreover, the silicon negative electrode was applied to an all-solid-state battery with a garnet-type oxide as a solid electrolyte and showed superior capacity retention.
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Free Research Field |
エネルギー材料
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Academic Significance and Societal Importance of the Research Achievements |
従来の化石燃料に依存した社会から脱却し、脱炭素社会の実現に向けたエネルギーシフトの機運が世界的に高まっている。脱炭素社会の実現に向けた電気自動車の普及化や太陽光や風力などの自然エネルギーの有効利用において、高性能な蓄電池が必要不可欠である。リチウムイオン電池の更なる大容量化を目指して、従来の黒鉛負極の約10倍の蓄電容量を有するシリコン系材料の実用化を目指した。本研究では、シリコン負極表面に人工的な被膜を形成することにより寿命特性を改善できることを示すとともに、特性改善に有効な被膜成分を明らかにした。
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