EFFECT OF ADDITION OF 1-BUTYL-3-METHYLIMIDAZOLIUM HEXAFLOUROPHOSPHATE (BMIMPF6) IONIC LIQUID ON THE ELECTROLYTE CONDUCTIVITY OF LITHIUM-ION BATTERIES

• Main Author: Pangestu, Ayunda
• Format: Final Project
• Language: Indonesia
• Subjects: Kimia
• Online Access: https://digilib.itb.ac.id/gdl/view/62814
• Institution: Institut Teknologi Bandung

The lithium-ion battery is one type of rechargeable battery that is widely used in electronic equipment. Generally, commercial lithium-ion batteries use an electrolyte based on organic carbonate solvent, which has volatile and flammable properties. Therefore, in this study, an electrolyte modification study was conducted to obtain an electrolyte system with high thermal stability and high conductivity. Ionic liquids have high thermal stability, high conductivity, and relatively high viscosity. Mixing the ionic liquid with organic carbonate solvent is expected to fix draw back of the conventional electrolyte of lithium-ion batteries. In this study, density and viscosity measurements were carried out using a pycnometer and Ostwald viscometer for electrolytes based on carbonate organic solvents and electrolytes with ionic liquid added. The organic carbonate solvent used was a mixture of ethylene carbonate (EC) with propylene carbonate (PC) (1:1, v/v), EC with dimethyl carbonate (DMC) (1:1, v/v), and EC with diethyl carbonate. (DEC) (1:1, v/v). Ionic liquid 1-butyl-3-methyl imidazolium hexafluorophosphate (BMIMPF6) was added to each mixture of organic carbonate solvents in the amount of 5 %(v/v). Before and after the addition of ionic liquid, the electrolyte system was measured using the Electrochemical Impedance Spectroscopy (EIS) method at temperatures of 30, 35, 40, 45, and 50 °C. The electrolyte modified by the addition of ionic liquid has a measured conductivity of >1 S cm 1, about ten times greater than that of conventional electrolytes. Characterization by cyclic voltammetry method was carried out for ferrocene in electrolyte samples before and after adding BMIMPF6 at various scanning rates 20, 40, 60, 80, 100, 200, and 300 mV s 1. The voltammogram of ferrocene on electrolyte which BMIMPF6 was added showed a quasi- reversible redox reaction with a diffusion coefficient of >1x10 6 cm2 s, ten times greater than that of conventional electrolytes. The addition of BMIMPF6 to the electrolyte system will increase ferrocene's conductivity and diffusion rate so that it has the potential as an electrolyte for lithium-ion batteries.