International Research Journal of Engineering and Technology (IRJET) e-ISSN: 2395-0056 Volume: 04 Special Issue: 09 | Sep -2017 www.irjet.net p-ISSN: 2395-0072 One Day International Seminar on Materials Science & Technology (ISMST 2017) 4 th August 2017 Organized by Department of Physics, Mother Teresa Women’s University, Kodaikanal, Tamilnadu, India © 2017, IRJET | Impact Factor value: 5.181 | ISO 9001:2008 Certified Journal | Page 15 PREPARATION AND PHYSICAL CHARACTERIZATION OF SULFUR/CARBON BLACK COMPOSITE CATHODE MATERIAL FOR Li-S BATTERY P.Rajkumar 1 , K.Diwakar 2 , R.Subadevi 3 , M.Sivakumar 4 1,2,3,4 #120, Energy Materials Lab, Department of Physics, Alagappa University, Karaikudi-630 003, Tamil Nadu, India. ( * Corresponding Author: susiva73@yahoo.co.in (M.Sivakumar) & susimsk@yahoo.co.in (R.Subadevi)) --------------------------------------------------------------------***---------------------------------------------------------------------- Abstract - Lithium sulfur batteries have been extensively nominated as one of the most capable candidate for next generation energy storage systems. However, it is still restricted owing to the low electronic conductivity of sulfur, volume expansion and polysulfide during shuttling. Herein, Sulur/Carbon black composite cathode material successfully prepared by ball milling method followed by heat treatment. The obtained composite cathode material was characterized for physical analyses using XRD, FTIR, RAMAN and SEM. From XRD analysis, the diffraction peak of the as-prepared sample displays the presence of elemental sulfur, which indicates the low content of carbon black has not been affected in its structure. SEM results reveal that the uniform distribution of sulfur in the S/CB composite. Hence, the uniform morphology of the prepared composite cathode material will enhance the electrochemical properties when it is used in the fabrication of the lithium sulfur battery. Key Words: Lithium sulfur battery, cathode material, ball milling, composite, carbon black 1. INTRODUCTION A favorable alternative for the next generation energy storage device, lithium sulfur battery has fascinated more and more attentions over the past few years. Multi- electron redox reaction provides it with a high theoretical specific capacity of 1675 mAh g -1 , which is five times higher than those of traditional lithium ion batteries. Moreover, its low cost and eco-friendliness, compared by other cathode materials for secondary lithium batteries, are additional advantage to be considered [1-4]. In spite of these advantages, the practical applications of Li-S batteries are still hindered by the low conductivity of sulfur, dissolution of lithium polysulfide intermediates and volume expansion of active material during cycling process. All these disadvantages mainly cause the low Coulombic efficiency, low consumption of sulfur and quick capacity decay [5]. In order to overcome the dissolution of intermediate lithium polysulfides, numerous efforts have been devised, such as adding highly conducting carbons, conductive polymers and metal oxides [6, 7]. Among them, carbonaceous materials are considered as the ideal choice for the loading sulfur, such as porous carbons, carbon black, hollow carbon spheres, carbon nanotube/fibers, etc. which can not only growth the conductivity of sulfur, but also can improve the dissolution of lithium polysulfides into organic liquid electrolytes [5]. For example, Su et al. reported a sulfur/carbon black composite cathode synthesized by a facile in situ sulfur deposition method to deliver a high initial discharge capacity of 1116 mAh g -1 and a reversible discharge capacity of 777 mAh g -1 after 50 cycles. Because the carbon materials effectively increase the electrical conductivity of sulfur, thereby improve the utilization of active materials [8, 9]. Herein, the sulfur/carbon black composite material prepared via ball milling method. The carbon material in the composite can physically confine sulfur, accommodate volume expansion and improve the electronic conductivity of the cathode. The prepared composite material has been characterized for its structural and morphological analyses using XRD, FTIR, Raman and SEM. 2. EXPERIMENTAL WORK The sulfur/carbon black composite was synthesized via ball milling process followed by heat treatment method. Sulfur and carbon black were taken in 7:3 ratios and manually mixed using mortar and pestle. The mixed powders were heated for 155 °C at 20 h using muffle furnace. Finally the sulfur/carbon black composite has been obtained and labeled as S/CB. MATERIALS CHARACTERIZATION A structural and morphological analysis of the as- prepared S/CB composite was identified by powder X-