Preparation and Characterization of Lithium Ion Conductive Organic/Inorganic Composite Solid Electrolyte

The purpose of this study was to improve the ionic conductivity and physical properties of a polymer electrolyte by complexing it with ceramic particles. First, a polymer/ceramic composite solid electrolyte was prepared by synthesizing a super porous silica aerogel powder and adding it to a slurry containing a polyethylene oxide (PEO)-based polymer electrolyte; then, the electrochemical properties of electrolyte of different compositions were confirmed. PEO and polymethyl methacrylate (PMMA) were copolymerized, the optimum ratio of lithium salt, plasticizer, and silica aerogel was determined, and ion conductivity of the composite electrolyte was improved. When the EO:Li ratio was 10:1, the glass transition temperature was the lowest, and the room-temperature ion conductivity was improved to 3.0 × 10⁻⁵ S/cm. As a result of XRD and thermal analysis, it was confirmed that the stability and durability of the electrolyte interface can also be improved by complexation of the polymer electrolyte with ceramic particles.