2023-11-01 アルゴンヌ国立研究所(ANL)
◆この技術は硫黄を含む固体電解質の粉末に対して行われ、電解質と電極の接触を最適化し、電池の充放電サイクルの回数を増やすことができました。さらに、コーティングにより電解質の酸化アルミニウム層が形成され、電解質の酸素との反応を減少させ、製造プロセスを改善しました。この成功により、固体電池技術の発展が期待されます。
＜関連情報＞
- https://www.anl.gov/article/borrowing-semiconductor-industry-knowhow-to-make-better-batteries
- https://onlinelibrary.wiley.com/doi/10.1002/adma.202300673
硫化物ベースの固体電解質粉末に多機能コーティングを施し、固体電池の加工性、安定性、性能を強化 Multifunctional Coatings on Sulfide-Based Solid Electrolyte Powders with Enhanced Processability, Stability, and Performance for Solid-State Batteries
Zachary D. Hood, Anil U. Mane, Aditya Sundar, Sanja Tepavcevic, Peter Zapol, Udochukwu D. Eze, Shiba P. Adhikari, Eungje Lee, George E. Sterbinsky, Jeffrey W. Elam, Justin G. Connell
Advanced Materials Published: 16 March 2023
DOI:https://doi.org/10.1002/adma.202300673
Abstract
Sulfide-based solid-state electrolytes (SSEs) exhibit many tantalizing properties including high ionic conductivity and favorable mechanical properties for next-generation solid-state batteries. Widespread adoption of these materials is hindered by their intrinsic instability under ambient conditions, which makes them difficult to process at scale, and instability at the Li||SSE and cathode||SSE interfaces, which limits cell performance and lifetime. Atomic layer deposition is leveraged to grow thin Al2O3 coatings on Li6PS5Cl powders to address both issues simultaneously. These coatings can be directly grown onto Li6PS5Cl particles with negligible chemical modification of the underlying material and enable exposure of powders to pure and H2O-saturated oxygen environments for ≥4 h with minimal reactivity, compared with significant degradation of the uncoated powder. Pellets fabricated from coated powders exhibit ionic conductivities up to 2× higher than those made from uncoated material, with a simultaneous decrease in electronic conductivity and significant suppression of chemical reactivity at the Li-SSE interface. These benefits result in significantly improved room temperature cycle life at high capacity and current density. It is hypothesized that this enhanced performance derives from improved intergranular properties and improved Li metal adhesion. This work points to a completely new framework for designing active, stable, and scalable materials for next-generation solid-state batteries.
