中性子でリチウムの流れを解明、固体電池の性能向上へ (Neutrons Reveal Lithium Flow Could Boost Performance in Solid-State Battery)

ad

2025-01-28 オークリッジ国立研究所 (ORNL)

オークリッジ国立研究所(ORNL)とデューク大学の研究チームは、中性子散乱を用いて、固体電解質材料であるリン酸硫化リチウムクロリド(Li₆PS₅Cl)内でのリチウムイオンの動きを原子レベルで観察しました。この観察により、リチウムイオンが固体内を液体電解質と同様に容易に拡散することが確認され、これがバッテリーの安全性向上、充電速度の高速化、寿命の延長に寄与する可能性が示唆されました。この成果は、次世代の固体電解質を用いたバッテリー開発において重要な知見を提供します。

<関連情報>

固体リチウム電解質における液体のようなダイナミクス Liquid-like dynamics in a solid-state lithium electrolyte

Jingxuan Ding,Mayanak K. Gupta,Carolin Rosenbach,Hung-Min Lin,Naresh C. Osti,Douglas L. Abernathy,Wolfgang G. Zeier & Olivier Delaire
Nature Physics  Published:06 January 2025
DOI:https://doi.org/10.1038/s41567-024-02707-6

中性子でリチウムの流れを解明、固体電池の性能向上へ (Neutrons Reveal Lithium Flow Could Boost Performance in Solid-State Battery)

Abstract

Superionic materials represent a regime intermediate between the crystalline and liquid states of matter. Despite the considerable interest in potential applications for solid-state batteries or thermoelectric devices, it remains unclear whether the fast ionic diffusion observed in superionic materials reflects liquid-like dynamics or whether the hops of mobile ions are inherently coupled to more conventional lattice phonons. Here we reveal a crossover from crystalline vibrations to relaxational dynamics of ionic diffusion in the superionic compound Li6PS5Cl, a candidate solid-state electrolyte. By combining inelastic and quasi-elastic neutron-scattering measurements with first-principles-based machine-learned molecular dynamics simulations, we found that the vibrational density of states in the superionic state strongly deviates from the quadratic behaviour expected from the Debye law of lattice dynamics. The superionic dynamics emerges from overdamped phonon quasiparticles to give rise to a linear density of states characteristic of instantaneous normal modes in the liquid state. Further, we showed that the coupling of lattice phonons with a dynamic breathing of the Li+ diffusion bottleneck enables an order-of-magnitude increase in diffusivity. Thus, our results shed insights into superionics for future energy storage and conversion technologies.

0402電気応用
ad
ad
Follow
ad
タイトルとURLをコピーしました