Chemical Science Review and Letters ISSN 2278-6783 Chem Sci Rev Lett 2017, 6(23), 1773-1778 Article CS192048071 1773 Research Article Conductivity and Viscosity Studies of Binary Mixtures of Dimethyl Carbonate and Dimethyl Sulphoxide Based Electrolyte for Li-Ion Battery at 298.15k Edimeh Agatha I 1 *, Cookey Grace A 1 , Maduelosi Jane N 1 and Abia Augustine A 2 1 Department of chemistry, Rivers State University, Nigeria 2 Department of Pure and Industrial Chemistry, University of Port Harcourt, Nigeria Introduction A battery is a source of electrical energy; it converts stored chemical energy to electrical energy [1]. Lithium ion battery (sometimes written as Li-ion battery or LIB) is a rechargeable battery (secondary battery). It is widely used in portable electronics and fast gaining popularity for military electric vehicles, aerospace applications [2], and fast becoming a common replacement for lead acid batteries. Li-ion battery has two electrodes and an electrolyte as basic components. A critical parameter for lithium ion battery is the role of the electrolyte as they act as passage for ionic charges. A good electrolyte should be environmentally friendly, inert to other cells components, good electrical insulator, have a wide electrochemical, mechanical and thermal stability. Above all it should be a good conductor. Recently it has been found that mixtures of cyclic and non-cyclic carbonates are very suitable as solvents for lithium ion-battery as optimum properties desired in an electrolyte is not exclusive in a single material [3]. Binary, ternary and quarternary systems are the primary focus. Nwokobia et al. [4], studied properties of binary mixtures of propylene carbonate (PC), and 1, 2-dimethoxyethane (DME) in LiClO 4 for Li-ion battery. Viscosity, density and conductivity measurements were taken by varying solvent ratio. They established the mixing ratio to be between 63- 68% DME. Maca et al. [5], compared specific conductivity and dielectric constants in different mixtures: Propylene carbonate (PC), ethylene carbonate (EC) and dimethylsulphoxide (DMSO) in different mixing ratios. The mixture of EC and DMSO gave the highest conductivity. Sirvaranja et al. [6], prepared electrolyte solution for Li-ion batteries by varying ratios of PC+DMC mixtures in a constant 0.1M salt solution. A maximum conductivity was obtained for 1:1V% PC:DMC. In this work conductivities of different mixtures of DMC-DMSO with different salt concentrations are studied. Conductivity is an important characteristic of an electrolyte and it is crucial for the improved life of the Li-ion battery. The choice of LiClO 4 stems from its property to completely dissociate in solutions and good solvation of its ions. It is used especially in organic solvents and often employed as battery electrolyte [7]. Hence its use in this Abstract Conductivity Measurement of Pure solvents of Dimethyl-Carbonate (DMC) and Dimethyl-Sulphoxide (DMSO) and their salt solutions containing 0.1M, 0.5M and 1M Lithium Perchlorate(LiClO 4 ) were determined with varying percentage solvent compositions (by volume) at 298.15K to determine the applicability of the electrolyte system for Li-ion battery. Densities, viscosities of the different solvent mixtures and their dielectric constant were also determined. The observed variations in conductivity of different solvent composition with LiClO 4 were explained on the basis of changes in viscosities and the dielectric constants. These changes have been said to be due to ion-ion, ion- solvent and solvent-solvent interactions within the mixed binary solutions. The values for viscosities and conductivities of the pure solvents and mixed solvents with LiClO 4 are different. The values for the mixed solvents fall in-between those of the pure solvents. With the addition of DMC, the viscosity of the mixture is lowered. This invariably increases ionic mobility and conductivity is improved. The conductivity decreases at higher concentration due to decrease in solvation. Hence 0.1M LiClO 4 solutions gave the highest molar conductivity. The ideal mixing ratio of DMC-DMSO binary mixed electrolyte system for best conductivity and invariably battery performance has been established at 50- 55% DMC. Since conductivity is higher at lower concentration, it is recommended that more work could be carried out at lower concentrations than 0.1M LiClO 4 . Keywords: Conductivity, Density, viscosity, dielectric constant, battery, solvents, dimethyl-Sulphoxide, electrolyte, ion-solvent interactions *Correspondence Author: Edimeh Agatha Email: Edimehisi@yahoo.com