Effect of Ag powder on the Electrochemical Properties of PEO-Based Solid Electrolytes

초록

Solid polymer electrolytes (SPEs) based on poly(ethylene oxide) (PEO) have attracted considerable attention for all-solid-state lithium batteries due to their excellent mechanical flexibility and chemical compatibility with lithium salts. However, the intrinsic high crystallinity of PEO limits the segmental motion of polymer chains, resulting in poor ionic conductivity and low electrochemical performance. To overcome this limitation, metallic silver (Ag) nanoparticles were investigated as an alternative to conventional ceramic fillers. Owing to their intrinsic electronic conductivity and strong affinity for lithium species, Ag nanoparticles were expected to modulate the polymer microstructure and enhance Li? transport. A systematic study was conducted by varying the particle size, loading content, and oxidation state to evaluate their effects on the morphology and ion transport behavior within the PEO matrix. Structural and electrochemical analyses revealed that the incorporation of Ag nanoparticles partially disrupted the crystalline regions of PEO, inducing localized amorphous domains that facilitated ion migration. Nevertheless, the overall enhancement in ionic conductivity was modest, mainly due to particle agglomeration and unstable interfacial interactions that hindered effective ion conduction. These results provide valuable insights into the complex interplay between metallic fillers and polymer electrolytes, emphasizing the importance of dispersion control and interfacial stability in designing high-performance solid polymer electrolytes for next-generation all-solid-state lithium batteries.