Perpustakaan Digital ITB

Liquid electrolytes in conventional lithium-ion batteries (LIB) pose safety issues and development barriers due to their volatility, flammability, and susceptibility to dendrite growth. Solid polymer electrolytes (SPE) are a promising alternative because they are non-volatile and non-flammable, have a wide electrochemical stability window (ESW), and can resist dendrite growth. However, CNC-PEO-based SPE has several drawbacks, particularly in terms of thermal stability, interfacial resistance with electrodes, and overall electrochemical performance, which need to be improved. Previous studies have shown that rare earth oxides (REO) can improve the performance of polymer electrolytes. However, the use of cerium oxide (CeO?) in CNC-PEO-based SPEs is limited. This research presents a new approach by utilizing the ability of CeO? in CNC-PEO-based SPE to reduce polymer crystallinity and bind salt anions through Lewis’s acid–base interactions, which can improve ion conductivity and the overall electrochemical performance. In this study, CeO2 was added as a filler in CNC-PEO-based SPE. CNC-PEO-LiTFSI without CeO2 addition and CNC-PEO-LiTFSI-10CeO2 with CeO2 addition were synthesized using solution casting methode. To analyze the crystal structure, X-ray diffraction (XRD) and differential scanning calorimetry (DSC) were performed. Thermal stability was characterized by thermogravimetry (TGA) and heating tests. The SPE membranes were assembled into CR2032 coin cells with LiFePO? as the cathode and lithium metal as the anode for electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV) and galvanostatic charge–discharge (CD) tests. Other cell configurations were assembled to evaluate the electrochemical properties of SPE membrane using electrochemical impedance spectroscopy (EIS), lithium transfer number (LTN), linear sweep voltammetry (LSV), and lithium stripping plating. The experimental results demonstrate that the CeO? as a filler into CNC–PEO-based SPE reduces polymer crystallinity and enhances thermal stability. Electrochemically, the CeO?-fortified samples exhibited superior performance with an ionic conductivity of 6.89 × 10?? S cm?¹, lithium transference number of 0.85, wider window voltage up of 5.3 V, and dendrite suppression up to 3000 cycles. In all-solid-state lithium-ion batteries (ASSLBs), the system also achieved a low interfacial resistance (462 ?), improved ion-transfer kinetics and reversibility, and a specific capacity of 108 mAh g?¹.