| Project/Area Number |
16K17969
|
|---|
| Research Category |
Grant-in-Aid for Young Scientists (B)
|
| Allocation Type | Multi-year Fund |
|---|
| Research Field |
Inorganic industrial materials
|
|---|
| Research Institution | The University of Tokyo (2018-2019)
National Institute of Advanced Industrial Science and Technology (2017)
National Institute for Materials Science (2016) |
|---|
Principal Investigator |
Haruyama Jun 東京大学, 物性研究所, 助教 (80772003)
|
|---|
| Project Period (FY) |
2016-04-01 – 2020-03-31
|
| Project Status |
Completed (Fiscal Year 2019)
|
| Budget Amount *help |
¥4,160,000 (Direct Cost: ¥3,200,000、Indirect Cost: ¥960,000)
Fiscal Year 2019: ¥1,040,000 (Direct Cost: ¥800,000、Indirect Cost: ¥240,000)
Fiscal Year 2018: ¥1,040,000 (Direct Cost: ¥800,000、Indirect Cost: ¥240,000)
Fiscal Year 2017: ¥910,000 (Direct Cost: ¥700,000、Indirect Cost: ¥210,000)
Fiscal Year 2016: ¥1,170,000 (Direct Cost: ¥900,000、Indirect Cost: ¥270,000)
|
|---|
| Keywords | 電極/電解質界面 / 第一原理計算 / Liイオン電池 / 全固体電池 / 電荷移動反応 / 電極/電解液界面 / グラファイト / リチウムイオン電池 / 界面抵抗 / 界面イオン拡散 / 固々界面 / 固固界面 / 固体電解質 |
|---|
| Outline of Final Research Achievements |
Large interfacial resistance in solid-state Li-ion battery is demanding for its practical application. We examined mutual diffusion properties of the cation elements at LiCoO2 electrode/Li3PS4 solid electrolyte interface by first-principles calculations. Evaluating formation energies of exchanging ions, we found that the mixing of Co and P is energetically preferable. These atomistic understandings can be meaningful for the development with smaller interfacial resistance. Next, charge transfer reaction (CTR) at the electrode/solution interface is a major component that limits the current densities of LIBs. We applied density functional theory calculations with implicit solvation theory for CTR at an interface of graphite electrode/electrolyte solution. We obtained the activation energy of 0.6 eV, which is consistent with the electrochemical impedance spectroscopy measurements. This study paves the way for the quantitative analysis of the CTRs in electrochemical devices.
|
| Academic Significance and Societal Importance of the Research Achievements |
全固体型LIBの問題点は正極/電解質界面のLiイオン伝導に大きな抵抗が発生することである. 界面抵抗の起源はまだ判明しておらず, その原因を考察することは発生機構の解明に重要である. 本研究では抵抗要因と考えられる正極/硫化物電解質の遷移金属元素の拡散の解析を行い, 交換欠陥を抑制する物質探索を将来的に可能にする結果を得た. 次に電解液を用いる液体型LIBは電荷移動抵抗が全抵抗の主な割合を占めるため, 電荷移動抵抗を低減することは充電時間の高速化などに重要となる. この結果, 様々な電極/電解液界面における電荷移動反応のシミュレーションが可能になり, 反応機構の理解を深めることが期待される.
|
