热处理提升Li7P3S11固态电解质的空气稳定性和电化学性能OA

All-solid-state lithium batteries(ASSLBs)are considered promising candidates for next-generation electric vehicle power sources owing to their high energy density,superior safety,and long cycle life.However,the poor chemical and electrochemical stability of sulfide-based solid electrolytes in ambient air severely hampers their large-scale application.In this study,we successfully synthesized Li7P3S11 solid electrolyte with a room-temperature ionic conductivity exceeding 1.0 mS/cm via a mechanochemical method.The effects of moisture exposure in air on its performance,as well as the subsequent influence of thermal treatment on its structure and ionic conductivity,were systematically investigated.It was found that air exposure reduces the crystallinity of Li7P3S11 and partially decomposes it into impurity phases,leading to a marked decrease in ionic conductivity.The thermally treated(270℃)Li7P3S11 was then incorporated into ASSLBs paired with a high-nickel layered cathode material(LiNi0.9Mn0.05Co0.05O2)and a Li-In alloy anode,using both a single-layer electrolyte structure and a bilayer configuration that included Li3InCl6.The results showed that both configurations achieved stable cycling for over 200 cycles,with the single-layer structure exhibiting higher specific capacity and better cycling stability.Electrochemical impedance spectroscopy revealed that the inferior performance of the bilayer structure was mainly attributed to increased interfacial resistance between Li7P3S11 and Li3InCl6 after air exposure.This work offers important experimental insights and design strategies for enhancing the practical performance of sulfide-based ASSLBs.