Enhancing solid-state polymer lithium battery performance with commercial-grade TiO2 additives: Toward industrial-scale applications

초록

Solid polymer electrolytes (SPEs) offer a safer and more stable alternative to conventional liquid electrolytes in lithium metal batteries (LMBs). In this study, commercially available, industrial-grade TiO2 nanoparticles were incorporated at low loadings (1-3 %) into a polyethylene oxide (PEO)-based SPE matrix via a facile and scalable mixing process. Remarkably, the SPE electrolyte containing 1 % TiO2 (SPE1) demonstrated superior properties, including a reasonable Li transference number of (tLi+ = 0.59), good ionic conductivity of 3.94 x 10-3 S/cm measured at 60 degrees C and reduced crystallinity as confirmed by DSC analysis. Intriguingly, SPE1 maintained a fluctuation-free lithium stripping/plating for a consecutive 450 h without obvious voltage fluctuation. Furthermore, the integrated LiFePO4 (LFP) ||Li solid-state cell yielded a discharge capacity of 126 mAh/g at 1C with 99 % coulombic efficiency after 300 cycles. The practical feasibility of the SPE1 electrolyte system is further demonstrated with a single-layer Li-ion pouch cell (3 cm x 4 cm), which supplied a specific capacity of 64.70 mAh/g after 20 cycles at 0.05C at 60 degrees C. This successful integration into pouch cell configuration demonstrates the viability of this SPE system for future scalable, safe, and high-performance solid-state LB applications.

키워드