A theoretical approach to address interfacial problems in all-solid-state lithium ion batteries: tuning materials chemistry for electrolyte and buffer coatings based on Li6PA5Cl hali-chalcogenides

• Published in: Journal of materials chemistry. A, Materials for energy and sustainability Vol. 7; no. 10; pp. 5239 - 5247
• Main Authors: Xu, Hongjie, Yu, Yuran, Wang, Zhuo, Shao, Guosheng
• Format: Journal Article
• Language: English
• Published: Cambridge Royal Society of Chemistry 2019
• Subjects: Buffers (chemistry); Cathodes; Chalcogenides; Chemical potential; Coated electrodes; Coatings; Conductors; electric potential difference; Electrochemistry; Electrolytes; Endurance; Interface reactions; Interface stability; Lithium; lithium batteries; Lithium-ion batteries; Organic chemistry; Rechargeable batteries; Solid state; sulfides
• ISSN: 2050-7488; 2050-7496; 2050-7496
• DOI: 10.1039/c8ta11151k

Even though ultra-fast Li+ ion conductors based on sulfides such as LGPS and Li6PS5Cl have been developed in recent years, rather limited advancement has been made towards developing all-solid-state lithium ion batteries due to serious interface-related problems. Here in this work, we have carried out extensive fundamental modelling to formulate a system of materials based on hali-chalcogenide Li6PA5Cl argyrodites (A is the site for chalcogen species), so that materials with chemically and structurally compatible characteristics can be used as both a superb electrolyte and excellent buffer coatings over electrode surfaces. All solid-state-batteries (ASSBs) in the form of Li|Li6PO4SCl|Li6PO5Cl|Li0.25MnO2 are thus recommended, so that buffer coatings based on O-rich hali-chalcogenides help avoid interfacial reactions, owing to their high stability with respect to the cathodes and greatly enhanced chemical potential with respect to Li/Li+. Such batteries fundamentally have high mechanical and electrochemical stability, thus enabling high performance and great endurance to operational voltage.