Improvement of High-Rate Performance of All-Solid-State Lithium Secondary Batteries Using LiCoO2 Coated with Li2O-SiO2 Glasses

Development of rate capability is one of the most important issues to be solved in all-solid-state lithium secondary batteries. The electrochemical performance of these batteries has been highly improved by coating LiCoO 2 particles with Li 2 O-SiO 2 thin film. The interfacial resistance between LiCoO 2 and the glass-ceramic electrolyte was decreased by those coatings. The rate capabilities of the cells using the coated LiCoO 2 particles were superior to that of the cell using noncoated LiCoO 2 . The Li 2 Si 3 coating was more effective than the SiO 2 coating in enhancing rate performance, suggesting that lithium-ion conductivity of the coating materials is important for high-rate performance.